Simulation Model of Brushless Excitation System
Directory of Open Access Journals (Sweden)
Ahmed N.A. Alla
2007-01-01
Full Text Available Excitation system is key element in the dynamic performance of electric power systems, accurate excitation models are of great importance in simulating and investigating the power system transient phenomena. Parameter identification of the Brushless excitation system was presented. First a block diagram for the EXS parameter was proposed based on the documents and maps in the power station. To identify the parameters of this model, a test procedure to obtain step response, was presented. Using the Genetic Algorithm with the Matlab-software it was possible to identify all the necessary parameters of the model. Using the same measured input signals the response from the standard model showed nearly the same behavior as the excitation system.
Application brushless machines with combine excitation for a hybrid car and an electric car
Directory of Open Access Journals (Sweden)
Gandzha S.A.
2015-08-01
Full Text Available This article shows advantages of application the brushless machines with combined excitation (excitation from permanent magnets and excitation winding for the hybrid car and the electric car. This type of electric machine is compared with a typical brushless motor and an induction motor. The main advantage is the decrease of the dimensions of electric machine and the reduction of the price for an electronic control system. It is shown the design and the principle of operation of the electric machine. The machine was modeled using Solidworks program for creating design and Maxwell program for the magnetic field analysis. The result of tests is shown as well.
Reversible thyristor converters of brushless synchronous compensators
Directory of Open Access Journals (Sweden)
А.М.Galynovskiy
2013-12-01
Full Text Available Behavior of models of three-phase-to-single-phase rotary reversible thyristor converters of brushless synchronous compensators in a circuit simulation system is analyzed. It is shown that combined control mode of opposite-connected thyristors may result in the exciter armature winding short circuits both at the thyristor feed-forward and lagging current delay angles. It must be taken into consideration when developing brushless compensator excitation systems.
A semiconductor laser excitation circuit
Energy Technology Data Exchange (ETDEWEB)
Kaadzunari, O.; Masaty, K.
1984-03-27
A semiconductor laser excitation circuit is patented that is designed for operation in a pulsed mode with a high pulse repetition frequency. This circuit includes, in addition to a semiconductor laser, a high speed photodetector, a reference voltage source, a comparator, and a pulse oscillator and modulator. If the circuit is built using standard silicon integrated circuits, its speed amounts to several hundred megahertz, if it is constructed using gallium arsenide integrated circuits, its speed is several gigahertz.
New Logic Circuit with DC Parametric Excitation
Sugahara, Masanori; Kaneda, Hisayoshi
1982-12-01
It is shown that dc parametric excitation is possible in a circuit named JUDO, which is composed of two resistively-connected Josephson junctions. Simulation study proves that the circuit has large gain and properties suitable for the construction of small, high-speed logic circuits.
Circuit design of DC brushless thruster speed measurement%直流无刷推进器转速测量电路设计
Institute of Scientific and Technical Information of China (English)
陈伟; 严卫生; 赵江
2012-01-01
Digital pulse noise,which comes from DC brushless thruster outputting,affects the DC brushless thruster speed measurement. This paper puts forward a DC brushless thruster speed measurement circuit design method. The circuit u-ses a voltage follower,photoelectric isolation technology,which can eliminate the digital pulse noise influence on measurement accuracy. And we calculate the propeller speed by using frequency to voltage converter and analog to digital converter. The test results indicate that the method can effectively eliminate the digital pulse noise. The method has a good stability and high speed measurement accuracy. It can well meet the requirements of DC brushless thruster speed measurement.%直流无刷推进器输出的数字脉冲信号存在毛刺干扰,影响对推进器转速的测量.提出一种直流无刷推进器去毛刺转速测量电路的设计方法.该电路采用电压跟随、光电隔离技术,消除数字脉冲毛刺干扰对测量精度的影响；通过F/V变换、A/D转换,由测得电压计算推进器转速.试验结果表明,该电路设计可以有效的去除毛刺干扰.该方法稳定性好、测速精度高,能很好的满足对直流无刷推进器转速测量的要求.
Renovating the excitation circuit of a conventional welding converter
Indian Academy of Sciences (India)
Gulderen Yildirmaz; M Hadi Sarul; Remzi Gulgun; Hulya Obdan
2006-02-01
This paper presents two different new excitation current supplies based on power electronics for an existing conventional welding converter. The proposed circuits are simulated using Lab-VIEW 1200 AI and a PC based system. In the expressions for winding currents the dynamic inductances are used to take into account the saturation in the core of the winding. The experimental circuits are implemented and tested. The percentage peak-to-peak ripple currents are calculated for both simulation and experimental results and for both circuit conﬁgurations. The results are summarized in two tables for comparison.
An excitable electronic circuit as a sensory neuron model
Medeiros, Bruno N S; Mindlin, Gabriel B; Copelli, Mauro; Leite, José R Rios
2011-01-01
An electronic circuit device, inspired on the FitzHugh-Nagumo model of neuronal excitability, was constructed and shown to operate with characteristics compatible with those of biological sensory neurons. The nonlinear dynamical model of the electronics quantitatively reproduces the experimental observations on the circuit, including the Hopf bifurcation at the onset of tonic spiking. Moreover, we have implemented an analog noise generator as a source to study the variability of the spike trains. When the circuit is in the excitable regime, coherence resonance is observed. At sufficiently low noise intensity the spike trains have Poisson statistics, as in many biological neurons. The transfer function of the stochastic spike trains has a dynamic range of 6 dB, close to experimental values for real olfactory receptor neurons.
The analysis and design of brushless D.C. motors
Benarous, Maamar
In modern computer systems electrical drives are used to rotate hard discs. These motors require special torque- speed characteristics. The speed of the hard disc must be constant in order for the unit to function correctly. One type of drive, which is used for hard discs is the brushless-DC-motor. This machine has permanent magnet excitation and a polyphase armature winding. It therefore takes the form of a synchronous machine, and in order to be brushless the armature winding is stationary and the excitation rotates. To run at adjustable speed a variable frequency supply is required. In the brushless D.C form the inverter output is phase locked to the rotor position, it is therefore electro-magnetically similar to the D.C machine where fixed brushes determine the frequency and phase of the current in the armature winding. In order to perform the phase lock action signals measuring the rotor position are needed. In one form of machine Hall effect probes detect the position of the rotor poles, in a second given that the rotor is in motion the induced back emf is used. Experimentally it is convenient to replace these magnet systems with a photo- transistor and rotating shutter system and this was the approach used in this thesis. The objective of this research is to investigate different aspects of this motor. The generation, measurement, and placement of signals is described and illustrated, and the design and construction of an inverter supply circuit is described. Both 2D and 3D finite element analysis is used in order to find the machine parameters as well as cogging torque analysis, using the concept of permanent magnet magnetisation characteristics. It is shown that the cogging can be reduced for certain types of magnetisation. The finite element analysis is taken further by connecting the drive circuit needed to run the machine into the finite element mesh, the machine parameters are defined using this method. The close agreement between the simulation and
Effects of cell cycle noise on excitable gene circuits
Veliz-Cuba, Alan; Bennett, Matthew R; Josić, Krešimir; Ott, William
2016-01-01
We assess the impact of cell cycle noise on gene circuit dynamics. For bistable genetic switches and excitable circuits, we find that transitions between metastable states most likely occur just after cell division and that this concentration effect intensifies in the presence of transcriptional delay. We explain this concentration effect with a 3-states stochastic model. For genetic oscillators, we quantify the temporal correlations between daughter cells induced by cell division. Temporal correlations must be captured properly in order to accurately quantify noise sources within gene networks.
Simplified Model of Brushless Synchronous Generator for Real Time Simulation
Lopez, M D; Rebollo, E; Blanquez, F R
2015-01-01
This paper presents a simplified model of brushless synchronous machine for saving hardware resources in a real time simulation system. Firstly, a brushless excitation system model is described. Thereafter, the simplified transfer function of an AC exciter and rotating diodes of the brushless excitation system is estimated. Finally, the complete system is simulated, comparing the main generator's voltage with both detailed and simplified excitation systems in several scenarios. These results show the accuracy of the simplified model against the detailed simulation model, resulting on an important hardware resources savings.
直流无刷高速电机驱动电路设计及改进%Design and Improvement of the High - speed Brushless DC Motor Drive Circuit
Institute of Scientific and Technical Information of China (English)
石屾; 董春
2011-01-01
采用无传感器无刷直流低速电机专用调速控制芯片ML4425,设计制作了航模用直流无刷高速电机的控制器.针对目前航模用直流无刷电机速度高的特点,对用于直流无刷低速电机的传统ML4425控制系统中的相关环节进行了改进,尤其是电机的启动、驱动和保护部分.简化了航模用直流无刷高速电机的控制系统,减少了成本.%In this paper,a dedicated control chip is used to design a drive circuit of a low speed sensorless DC brushless motor.This paper has done some change of the traditional control system of ML4425,in order to adapt to the high speed of the DC brushless motor used in aircraft model, especially in parts of start, drive and protect.Simplified the control system of the DC brushless motor,so it can reduce the cost.
Rotor position sensor switches currents in brushless dc motors
1965-01-01
Reluctance switch incorporated in an induction motor is used for sensing rotor position and switching armature circuits in a brushless dc motor. This device drives the solar array system of an unmanned space satellite.
Mathematical modeling of electromechanical processes in a brushless DC motor
Directory of Open Access Journals (Sweden)
V.I. Tkachuk
2014-03-01
Full Text Available On the basis of initial assumptions, a mathematical model that describes electromechanical processes in a brushless DC electric motor with a salient-pole stator and permanent-magnet excitation is created.
Institute of Scientific and Technical Information of China (English)
张爽; 邹建华
2015-01-01
Taking TZYW/TAW 7 800-18/3 250 W THF1 positively pressurized enclosure/safety-increasing type synchronous motor with brushless excitation, which was used to equipped with a compressor from abroad, as an example, the advantages in the fields of explosion-proof of the positively pressurized enclosure/safety-increasing type synchronous motor with brushless excitation was described while key points in designing of the synchronous motor with single-supporting was introduced as well as the supe-riorities resulted from the comparison with the same kind motor.%以一台为国外压缩机配套的TZYW/TAW 7800-18/3250 WTHF1正压外壳/增安型无刷励磁同步电动机为例，叙述了正压外壳/增安型无刷励磁同步电动机的防爆优越性，介绍了单支撑同步电机的设计关键点，以及与同类电机相比后该类电机的优势。
Control motor brushless sensorless
Solchaga Pérez de Lazárraga, Gonzalo
2015-01-01
El proyecto consiste en la creación de un circuito capaz de controlar la velocidad de un motor brushless sensorless. Este tipo de motores eléctricos tienen como característica que no tienen escobillas para cambiar la polaridad del bobinado de su interior y tampoco precisan de un sensor que indique que ha realizado una vuelta. Los motores brushless que son controlados por este tipo de circuitos son específicos para aeronaves no tripuladas y requieren un diseño diferente a un motor brushless pe...
Institute of Scientific and Technical Information of China (English)
王铮; 刘卫国; 焦宁飞; 杨南方
2012-01-01
In allusion to aero brushless synchronous starter/generator system, the characteristics of the excitation system were researched under the single-phase AC excitation condition. Under the single-phase AC excitation condition, the output voltage characteristic of the magnetizing exciter was analyzed in stationary state by using the finite element analysis method. The main generator excitation characteristic was also studied, and the generator optimal excitation condition was found and verified by experiment. In rotating state, the characteristic of the main generator excitation was analyzed under the single-phase AC excitation condition and DC excitation condition respectively. By comparing the DC and AC excitation characteristic curve, the optimal speed range for AC/DC switching was obtained.%针对航空无刷同步起动／发电机,进行了单相交流励磁下励磁系统的特性研究.利用有限元仿真分析方法,对单相励磁下励磁机静止时的电压输出特性进行研究,并探讨主发电机的励磁特性,寻求主发电机最优励磁条件并通过试验进行验证；开展旋转状态下交流和直流励磁时主发电机励磁特性分析；通过对比直流励磁特性曲线与交流励磁特性曲线,得到励磁机交／直流励磁最优切换区间.
Institute of Scientific and Technical Information of China (English)
白娅梅; 罗玲; 黄其
2012-01-01
The design of 9kW permanent magnet brushless DC motor using the combination of magnetic circuit and electromagnetic field solution was presented in the paper. Main electromagnetic parameters, the number and shape of stator slot, the structure of stator and rotor were determined by using the equivalent magnetic circuit while no-load electromagnetic field and speed-torque characteristic were analyzed by means of electromagnetic field analysis software MagNet. The test values of no-load speed and current of the prototype motor match well with the results of simulation analysis. The validity of this method was shown in the motor design.%采用场路结合法设计9kW永磁无刷直流电动机,用磁路法确定电机的主要电磁参数、定子槽数和槽形、转子的磁路结构,运用电磁场分析软件MagNet分析计算空载磁场和机械特性,样机的空载转速、电流与仿真分析结果相一致,验证了采用场路结合法设计电机的有效性.
Sinusoidal excitation on the Chua's circuit simulation of limit cycles and chaos
DEFF Research Database (Denmark)
Lindberg, Erik
1994-01-01
Experiments with modelling and simulation of sinusoidal excitation on Chua's circuit are presented. It is demonstrated that the behaviour of the circuit is based on the interaction of two different kinds of energy balance: chaotic behaviour based on a balance between two unstable “states...
Laser cooling and optical detection of excitations in a LC electrical circuit
DEFF Research Database (Denmark)
Taylor, J. M.; Sørensen, Anders Søndberg; Marcus, Charles Masamed;
2011-01-01
We explore a method for laser cooling and optical detection of excitations in a room temperature LC electrical circuit. Our approach uses a nanomechanical oscillator as a transducer between optical and electronic excitations. An experimentally feasible system with the oscillator capacitively...
Self-Excited Single-Stage Power Factor Correction Driving Circuit for LED Lighting
Yong-Nong Chang
2014-01-01
This pa per proposes a self-excited single-stage high power factor LED lighting driving circuit. Being featured with power factor correction capability without needing any control devices, the proposed circuit structure is with low cost and suitable for commercial production. The power factor correction function is accomplished by using inductor in combination with a half-bridge quasi resonant converter to achieve active switching and yield out voltage regulation according to load requirement...
Institute of Scientific and Technical Information of China (English)
XU Xing-Lei
2007-01-01
Mesoscopic damped mutual capacitance coupled double resonance circuit is quantized by the method of damped harmonic oscillator quantization. Hamiltonian is diagonalized by the method of unitary transformation. The energy spectra of this circuit are given. The quantum fluctuations of the charge and current of each loop are investigated by the method of thermofield dynamics (TFD) in thermal excitation state,thermal squeezed vacuum state,thermal vacuum state and vacuum state. It is shown that the quantum fluctuations of the charge and current are related to not only circuit inherent parameter and coupled magnitude,but also quantum number of excitation,squeezed coefficients,squeezed angle and environmental temperature. And the quantum fluctuations increase with the increase of temperature and decay with time.
Institute of Scientific and Technical Information of China (English)
周德佳; 庄亚平; 冀路明; 徐定海; 李江
2011-01-01
精密品质的400Hz船用中频供电系统是特种装备可靠运行的重要保障,研究高性能的中频同步发电机励磁控制策略和工程应用非常重要。本文分析了中频供电系统瞬变电压调整特性,提出了具有电流前馈的中频无刷励磁系统PID控制算法,能够对励磁机的时间常数进行一定的补偿,降低其滞后效果,因此增加了励磁系统小信号响应带宽的能力,以满足中频供电系统在突加或突卸负载的工况下,中频发电机机端输出瞬变电压具有快速的恢复时间。实验结果与仿真相符合,系统输出电压具有良好的动稳态性能,表明了所提出的控制方案是有效的。%It is very important to study medium frequency synchronous generator＇s excitation control strategy and application in shipboard,for it can guarantee the safe operation of special equipment in high quality 400Hz medium frequency electrical system.In order to make the medium frequency synchronous generator terminal＇s transient voltage restores as quickly as possible under the circumstances of suddenly increased and decreased load,this paper analyzes regulating property of the transient voltage of medium frequency electrical system and puts forward PID with current feed-forward controlling algorithm for medium frequency brushless excitation system,which compensates the exciter time constant to some extent,decreases its delaying effect,and increases the small signal response bandwidth of the excitation system.The simulation and experimental results verify the effectiveness of the proposed algorithm,which demonstrate that the proposed control system has good dynamic stability and steady-state performance.
Self-Excited Single-Stage Power Factor Correction Driving Circuit for LED Lighting
Directory of Open Access Journals (Sweden)
Yong-Nong Chang
2014-01-01
Full Text Available This pa\tper proposes a self-excited single-stage high power factor LED lighting driving circuit. Being featured with power factor correction capability without needing any control devices, the proposed circuit structure is with low cost and suitable for commercial production. The power factor correction function is accomplished by using inductor in combination with a half-bridge quasi resonant converter to achieve active switching and yield out voltage regulation according to load requirement. Furthermore, the zero-voltage switching in the half-bridge converter can be attained to promote the overall performance efficiency of the proposed circuit. Finally, the validity and production availability of the proposed circuit will be verified as well.
Analysis of torque-current characteristic of brushless DC motor driven by three-phase H-bridge
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Presents the simulation and analysis of the steady state characteristic of a brushless DC motor studies the torque-current characteristic of the motor as well and discusses the design of a current-measure circuit for torque controlling.
Wu, Guohong; Shirato, Hideyuki
SCG (Superconducting Generator) has a superconducting field winding, which leads to many advantages such as small size, high generation efficiency, low impedance, and so on, and be considered as one of the candidates to meet the needs of high stability and high efficiency in the future power system networks. SCG with high response excitation is especially expected to be able to enhance the transient stability of power system by its SMES (Superconducting Magnetic Energy System) effect. The SMES effect of SCG is recognized that its behaviors are dominated by the structures and controls of its excitation system. For this reason, in order to verify exactly how the SMES effect of SCG influences on the power system stability, the electrical circuits of SCG high response excitation are modeled in detail for conducting digital simulation, and its influence on excitation voltage and active power output of SCG are discussed as well. The simulation results with a typical one machine - infinite bus power system model shows that the SMES effect can be certainly obtained when its exciting power is supplied from SCG terminal bus and may considerably lead to an improvement of power system transient stability.
Zagha, Edward; Murray, John D; McCormick, David A
2016-01-01
Cortical feedback pathways are hypothesized to distribute context-dependent signals during flexible behavior. Recent experimental work has attempted to understand the mechanisms by which cortical feedback inputs modulate their target regions. Within the mouse whisker sensorimotor system, cortical feedback stimulation modulates spontaneous activity and sensory responsiveness, leading to enhanced sensory representations. However, the cellular mechanisms underlying these effects are currently unknown. In this study we use a simplified neural circuit model, which includes two recurrent excitatory populations and global inhibition, to simulate cortical modulation. First, we demonstrate how changes in the strengths of excitation and inhibition alter the input-output processing responses of our model. Second, we compare these responses with experimental findings from cortical feedback stimulation. Our analyses predict that enhanced inhibition underlies the changes in spontaneous and sensory evoked activity observed experimentally. More generally, these analyses provide a framework for relating cellular and synaptic properties to emergent circuit function and dynamic modulation. PMID:27595137
Murray, John D.; McCormick, David A.
2016-01-01
Abstract Cortical feedback pathways are hypothesized to distribute context-dependent signals during flexible behavior. Recent experimental work has attempted to understand the mechanisms by which cortical feedback inputs modulate their target regions. Within the mouse whisker sensorimotor system, cortical feedback stimulation modulates spontaneous activity and sensory responsiveness, leading to enhanced sensory representations. However, the cellular mechanisms underlying these effects are currently unknown. In this study we use a simplified neural circuit model, which includes two recurrent excitatory populations and global inhibition, to simulate cortical modulation. First, we demonstrate how changes in the strengths of excitation and inhibition alter the input–output processing responses of our model. Second, we compare these responses with experimental findings from cortical feedback stimulation. Our analyses predict that enhanced inhibition underlies the changes in spontaneous and sensory evoked activity observed experimentally. More generally, these analyses provide a framework for relating cellular and synaptic properties to emergent circuit function and dynamic modulation. PMID:27595137
Digital Signal Controller Based Digital Control of Brushless DC Motor
Directory of Open Access Journals (Sweden)
Anjana Elizabeth Thomas
2013-07-01
Full Text Available This paper presents the digital control of a brushless dc (BLDC motor using TMS320F2812 DSP controller and an EPROM. The real-time control of electrical motors is an application area that is not usually the domain of Digital Signal Processors. The TMS320F2812 has got dedicated modules for digital motor control. Control algorithms used for the control has been in TMS320F2812 DSP controller. The output of the driver is 6 independent PWM pulses that have to be given to the corresponding gates of the six MOSFETs power switches used in the three-phase bridge driving circuit whose output is given to the stator of the Brushless DC Motor. The commutation technique used in this work is the trapezoidal commutation owing to its excellent speed and current control and it has been implemented using an EPROM
Xu, Xing-Lei; Li, Hong-Qi; Wang, Ji-Suo
2007-08-01
Based on the scheme of damped harmonic oscillator quantization and thermo-field dynamics (TFD), the quantization of mesoscopic damped double resonance RLC circuit with mutual capacitance-inductance coupling is proposed. The quantum fluctuations of charge and current of each loop in a squeezed vacuum state are studied in the thermal excitation case. It is shown that the fluctuations not only depend on circuit inherent parameters, but also rely on excitation quantum number and squeezing parameter. Moreover, due to the finite environmental temperature and damped resistance, the fluctuations increase with the temperature rising, and decay with time.
Institute of Scientific and Technical Information of China (English)
Xu Xing-Lei; Li Hong-Qi; Wang Ji-Suo
2007-01-01
Based on the scheme of damped harmonic oscillator quantization and thermo-field dynamics(TFD),the quantization of mesoscopic damped double resonance RLC circuit with mutual capacitance-inductance coupling iS proposed.The quantum fluctuations of charge and current of each loop in a squeezed vacuum state are studied in the thermal excitation case.It is shown that the fluctuations not only depend on circuit inherent parameters.but also rely on excitation quantum number and squeezing parameter.Moreover.due to the finite environmental temperature and damped resistance,the fluctuations increase with the temperature rising.and decay with time.
Sensorless Operation of Brushless DC Motor Drive using Back EMF Technique
Directory of Open Access Journals (Sweden)
R. Saranya, S. Saravana kumar,R. Baskaran, A. Vinidha Roc, K. Sathiyasekar
2014-04-01
Full Text Available The Brushless Direct Current (BLDC motors are one of the motor types that is gaining rapid popularity. Its major appliances include refrigerators, washing machines, vacuum cleaners, freezers, etc. As the name implies, BLDC motors do not use brushes for commutation; instead, they are electronically commutated. This paper proposes a new optimized technique for the Sensorless operation of permanent magnet brushless direct current (BLDC motor, which is based on back Electro Motive Force (back EMF, Zero Crossing Detection (ZCD. This proposed commutation technique of BLDC motor significantly reduces sensing circuits and cost of motor drive.
Control aspects of the brushless doubly-fed machine
Lauw, H. K.; Krishnan, S.
1990-09-01
This report covers the investigations into the control aspects of a variable-speed generation (VSG) system using a brushless double-fed generator excited by a series-resonant converter. The brushless double-fed machine comprises two sets of stator 3-phase systems which are designed with common windings. The rotor is a cage rotor resembling the low-cost and robust squirrel cage of a conventional induction machine. The system was actually designed and set up in the Energy Laboratory of the Department of Electrical and Computer Engineering at Oregon State University. The series-resonant converter designed to achieve effective control for variable-speed generation with the brushless doubly-fed generator was adequate in terms of required time response and regulation as well as in providing for adequate power quality. The three elements of the VSG controller, i.e., voltage or reactive power controller, the efficiency maximizer and the stabilizer, could be designed using conventional microprocessor elements with a processing time well within the time period required for sampling the variables involved with executing the control tasks. The report treats in detail the stability problem encountered in running the machine at certain speed regions, even if requirements for steady-state stability are satisfied. In this unstable region, shut down of the VSG system is necessary unless proper stabilization controls are provided for. The associated measures to be taken are presented.
Collective of mechatronics circuit
International Nuclear Information System (INIS)
This book is composed of three parts, which deals with mechatronics system about sensor, circuit and motor. The contents of the first part are photo sensor of collector for output, locating detection circuit with photo interrupts, photo sensor circuit with CdS cell and lamp, interface circuit with logic and LED and temperature sensor circuit. The second part deals with oscillation circuit with crystal, C-R oscillation circuit, F-V converter, timer circuit, stability power circuit, DC amp and DC-DC converter. The last part is comprised of bridge server circuit, deformation bridge server, controlling circuit of DC motor, controlling circuit with IC for PLL and driver circuit of stepping motor and driver circuit of Brushless.
Malik, Naveed ur Rehman
2012-01-01
This thesis deals with the steady-state, dynamic and control aspects of new type of brushless configuration of a doubly-fed induction machine in which the slip rings and carbon brushes are replaced by rotating power electronics and a rotating exciter. The aim is to study the stability of this novel configuration of the generator under mechanical and grid disturbances for wind power applications. The derivation, development and analysis of the steady-state model of the brushless doubly-fed ind...
Directory of Open Access Journals (Sweden)
Uma Devi Kumaravelu
2012-01-01
Full Text Available A method of simulation and modeling outer rotor permanent magnet brushless DC (ORPMBLDC motor under dynamic conditions using finite element method by FEMM 4.2 software package is presented. In the proposed simulation, the torque developed at various positions of the rotor, under a complete cycle of excitation of the stator, is analysed. A novel method of sinusoidal excitation is proposed to enhance the overall torque development of ORPMBLDC motor.
Institute of Scientific and Technical Information of China (English)
Hao Kuan-Sheng; Huang Song-Ling; Zhao Wei; Wang Shen
2011-01-01
This paper presents an analytical method for electromagnetic acoustic transducers (EMATs) under voltage excitation and considers the non-uniform distribution of the biased magnetic field. A complete model of EMATs including the non-uniform biased magnetic field, a pulsed eddy current field and the acoustic field is built up. The pulsed voltage excitation is transformed to the frequency domain by fast Fourier transformation (FFT). In terms of the time harmonic field equations of the EMAT system, the impedances of the coils under different frequencies are calculated according to the circuit-field coupling method and Poynting's theorem. Then the currents under different frequencies are calculated according to Ohm's law and the pulsed current excitation is obtained by inverse fast Fourier transformation (IFFT).Lastly, the sequentially coupled finite element method (FEM) is used to calculate the Lorentz force in the EMATs under the current excitation. An actual EMAT with a two-layer two-bundle printed circuit board (PCB) coil, a rectangular permanent magnet and an aluminium specimen is analysed. The coil impedances and the pulsed current are calculated and compared with the experimental results. Their agreement verified the validity of the proposed method. Furthermore, the influences of lift-off distances and the non-uniform static nagnetic field on the Lorentz force under pulsed voltage excitation are studied.
A New Rb Lamp Exciter Circuit for Rb atomic clocks and Studies on Transition from Ring to Red mode
Singh, Savita; Saxena, G M
2010-01-01
In this paper we describe the development of novel RF exciter circuit for electrode less Rb lamp. The lamp exciter circuit is a RF oscillator with a a new configuration operating at 60 to 65 MHz frequency with 3 to 4 watt power. The Rb lamp is used in exciting the ground state hyperfine transitions in Rb atom in a glass cell placed inside a tuned microwave cavity, As the frequency of these hyperfine transitions is very stable it is used in the development of Rb atomic clock by phase locking the oven controlled crystal oscillator (OCXO) to this atomic transition frequency. The details of the Rb lamp exciter are presented in the paper.The Lamp is ideally operated in ring mode as in this mode the linewidth is narrow and there is no self reversal. However, high temperature and RF excitation power may drive the Rb lamp to red mode which gives rise to line broadening and self reversal. It is the experience that mode change from ring to red deteriorates the atomic signal strength and S/N. In this paper the reasons o...
Simulation of asynchronous modes of synchronous motors with capacitors in the excitation circuit
Malyar, V. S.; Malyar, A. V.; I. A. Dobushovska
2012-01-01
Розглядається проблема розрахунку асинхронних режимів синхронних двигунів з конденсаторами в обмотці збудження. Задача розв'язується як крайова для нелінійної системи диференціальних рівнянь електричної рівноваги, в яких потокозачеплення контурів обчислюються шляхом розрахунку магнітного поля двигуна на основі теорії магнітних кіл. A problem of calculating asynchronous modes of synchronous motors with capacitors in the excitation circuit is considered. The problem is solved as a boundary o...
Loss analysis of permanent magnet hybrid brushless machines with and without HTS field windings
Chau, KT; Liu, C; Li, W
2010-01-01
This paper presents and implements the power loss analysis of a new kind of permanent magnet hybrid brushless (PMHB) machines with and without using high-temperature superconductor (HTS) field windings. The circuit-field-torque time-stepping finite element method together with experiential equations is developed to perform power loss analysis of the PMHB machine. Experimentation is carried out to verify the proposed loss analysis. © 2006 IEEE.
The design and analysis of a novel brushless dc linear motor
Basak, A.; Filho, A. F. Flores
1994-05-01
A novel brushless dc linear motor was designed, with two armature cores and seven high energy product magnets. It was then built and tested. Both the design and the analysis were carried out assuming a linear magnetic circuit. The design procedure and the test results are presented and discussed in this paper. The new motor can also be used as a slotless linear stepping motor.
Equivalent Magnetic Circuit Model of Flux-switching Hybrid Excitation Machine%混合励磁磁通切换电机等效磁路模型
Institute of Scientific and Technical Information of China (English)
许泽刚; 谢少军; 毛鹏
2011-01-01
混合励磁磁通切换电机（flux-switching hybrid excitationmachine,FSHM）是一种新型定子励磁型交流无刷电机,具有磁链双极性、结构简单、功率密度高、运行可靠等优点。改变电励磁绕组电流的大小和方向,实现了对永磁气隙磁场的有效调节与控制,而引入导磁磁桥可提升气隙磁场调节范围。以建立电枢绕组磁链最大位置的等效磁路模型为切入点,推导了峰值磁通表达式,探索了磁桥段相对磁导率的估算方法,结合有限元仿真分析了磁桥厚度变化与磁桥式FSHM初始气隙磁密、磁桥磁密、气隙磁场调节能力、磁力线路径转移等特性的关系。样机的有限元仿真及实验结果与等效磁路模型预测趋势基本一致,验证了建模方法与理论分析的正确性,可用于指导磁通切换电机的设计与性能分析。%Flux-switching hybrid excitation machine（FSHM） was an interesting brushless machine with magnets in the stator,which offered the advantages of bipolar flux linkage,simple and robust rotor structure and high power density.Adjustment and control of the PM air gap magnetic field could be achieved by means of controlling the field winding current,and magnetic bridge amplified the effect of field flux on PM flux.This paper took equivalent magnetic circuit model（EMCM） of maximum phase flux-linkage position as point of penetration,deduced the equation of peak magnetic flux,and explored a method for estimating the relative permeability of magnetic bridge.The characteristic relation between the thickness of magnetic bridge and initial air gap flux density,magnetic bridge flux density,regulating capacity of air gap magnetic field,and magnetic lines transfer were studied combined with finite element analysis（FEA）.The estimation results based on EMCM agreed well with the FEA and experiment data,which confirmed the correctness of modeling method and theoretical analysis.It provided reference for
Institute of Scientific and Technical Information of China (English)
XIAO Dongping; LEI Hui; ZHANG Zhanlong; HE Wei
2013-01-01
This work is carried out to predict the special distribution of electric field induced by multi-circuit intersecting overhead high-voltage (HV) transmission lines (TLs) within a large range without any expensive and time-consuming computation.The two main parts of the presented methodology are 1) setting up a three-dimensional (3D) model to calculate the electric field based on combining catenary equations with charge simulation method and 2) calculating the hybrid electric field excited by multi-circuit intersecting TLs using coordinate transformation and superposition technique.Examples of different TLs configurations,including a 220 kV single-circuit horizontally configured TLs,a 500 kV single-circuit triangularly configured TLs and a combination of the 220 kV TLs and the 550 kV TLs,are illustrated to verify the validity of this methodology.A more complicatal configurations,including a 500 kV double-circuit TLs and two 220kV single-circuit horizontally configured TLs,are also calculated.Conclusions were drawn from the simulation:1) The presented 3D model outperforms 2D models in describing the electric field distribution generated by practical HV TLs with sag and span.2) Coordinate transformation and superposition technique considerably simplify the electric field computation for multi-circuit TLs configurations,which makes it possible to deal with complex engineering problems.3) The electric field in the area covered by multiple intersecting overhead TLs is distorted and the hybrid electric field strength in some partial region increases so sharply that it might exceed the admissible value.4) The configuration parameters of the TLs and the spatial configuration of multi-circuit TLs,for instance,the height of TLs,the length of span and the intersection angle of multiple circuits,influence the strength and the distribution of hybrid electric field.The influence regularities summarized in this paper can be referred by future TL designs to meet the electromagnetic
无刷直流电动机的DSP控制%DSP Control of Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
王越; 甄长飞
2012-01-01
According to the characteristics of the brushless dc motor, and the demand in practical application, design solved the rapid control problem of brushless dc motor. Using the TMS320LF2407A of the TI company as control core, and PWM and PI, we designed control circuit and control procedures for brushless dc motor in order to achieve the actual effect.%为解决无刷直流电动机的快速控制问题，提出了无刷直流电动机的DSP控制方法。采用TI公司的TMS320LF2407A芯片为控制核心，结合PWM和PI调节设计无刷直流电动机的控制电路以及控制程序，以达到节能和使电动机快速启动的效果。
Axial flux permanent magnet brushless machines
Gieras, Jacek F; Kamper, Maarten J
2008-01-01
Axial Flux Permanent Magnet (AFPM) brushless machines are modern electrical machines with a lot of advantages over their conventional counterparts. They are being increasingly used in consumer electronics, public life, instrumentation and automation system, clinical engineering, industrial electromechanical drives, automobile manufacturing industry, electric and hybrid electric vehicles, marine vessels and toys. They are also used in more electric aircrafts and many other applications on larger scale. New applications have also emerged in distributed generation systems (wind turbine generators
Jingang Bai; Quanbin Zhao; Jing Zhao; Chengde Tong; Qian Wu; Ping Zheng
2012-01-01
A new type of brushless double rotor machine (BDRM) is proposed in this paper. The BDRM is an important component in compound-structure permanent-magnet synchronous machine (CS-PMSM) systems, which are promising for power-split hybrid electric vehicle (HEV) applications. The BDRM can realize the speed adjustment between claw-pole rotor and permanent-magnet rotor without brushes and slip rings. The structural characteristics of the BDRM are described and its magnetic circuit model is built. Re...
High temperature brushless DC motor system and its operation mode control
Institute of Scientific and Technical Information of China (English)
邹继斌; 胡建辉; 徐永向
2001-01-01
The high temperature ( 175 ℃ ) operation of a motor spells out special requirements for control algorithms, materials and elements. The stability of motor characteristic is guaranteed by the digital control strategy. Constant velocity operation is achieved by phase-locked loop ( PLL), and constant power operation is achieved by a current-restricting circuit. A motor for constant speed and constant power operation has been built and the speed control system is tuned by MATLAB simulation. Experimental and simulation results for operation mode control of brushless DC motor are presented.
Magnetic Circuit & Torque Analysis Of Brushless DC Motor
Directory of Open Access Journals (Sweden)
Arif J. Abbas
2013-05-01
Full Text Available This work is concerned with magnetic and torque analysis of BLDCM and with development of a method of designing BLDCM that have symmetric winding on the rotor .make significant contribution to the rotor inductance position difficult. It is also show that the prediction detent torque can be extremely sensitive to the permanent magnet by altering magnet arc width. Finally, simple lumped models that allow one to predict motor performance and characteristics as a function of main dimension, magnet residual flux density and phase current are developed. These models are used as a basis for an approach to designing BLDCM
Brushless direct-current motor with stationary armature and field
Studer, P. A.
1970-01-01
Electronically commutated dc motor has an active fixed field winding, and active fixed armature winding, and passive rotor. By use of brushless dc motor switching technique, motor provides continuous controllable and reversible torque without use of sliding contacts.
Universal Brushless-DC Motor Controller for Space Applications Project
National Aeronautics and Space Administration — The goal of this SBIR is to adapt an initial prototype ultra-miniature high-performance brushless-DC-motor controller, code named 'Puck', for use by NASA across a...
Comparative analysis of some brushless motors based on catalog data
Directory of Open Access Journals (Sweden)
Anton Kalapish
2005-10-01
Full Text Available Brushless motors (polyphased AC induction, synchronous and brushless DC motors have no alternatives in modern electric drives. They possess highly efficient and very wide range of speeds. The objective of this paper is to represent some relation between the basic parameters and magnitudes of electrical machines. This allows to be made a comparative analysis and a choice of motor concerning each particular case based not only on catalogue data or price for sale.
Permanent magnet brushless motor control based on ADRC
Li Xiaokun; Wang Song; Wang XiaoFan; Shi Tingting
2016-01-01
Permanent magnet brushless motor is a nonlinear system with multiple variables, the mathematical model of Permanent magnet brushless motor is difficult to establish, and since that the classic PID control is hard to precisely control the motor. Active disturbance rejection control (ADRC) technique is a new nonlinear controller which does not depend on the system model. It is starting from the classic PID control, and establishing the loop control system by error negative feedback, the ESO(ext...
Summary on Sensorless permanent magnet Brushless DC Motor Control Strategies
Directory of Open Access Journals (Sweden)
Li Hai Xia
2016-01-01
Full Text Available This paper aims at discussing the development process and application of permanent magnet brushless DC motor. By referring to the related literatures, this thesis gives an overview of several common non-position sensor detection technologies, analyzing their strengths and weaknesses as well as a number of new and improved methods in practical applications. Besides, The application situation of the electric door with sensorless permanent magnet brushless DC motor was illustrated.
An enhanced Z-source inverter topology-based permanent magnet brushless DC motor drive speed control
Geno Peter, P.; Rajaram, M.
2015-08-01
In this paper, an enhanced Z-source inverter (ZSI) is introduced for controlling the speed of permanent magnet brushless DC motor (PMBLDCM) drive. It is the extension of the conventional ZSI and the elements used in the circuit are the same as those of the conventional ZSI, except that the position of Inverter Bridge and diode would be exchanged from the classical circuit diagram. This exchanged circuit avoids the startup path of the inrush current and hence reduces the inrush current and improves the motor efficiency. Different modes of enhanced ZSI are studied with PMBLDCM. The voltage polarity of Z-source capacitors in the proposed circuit is the same as that of the input voltage polarity. Furthermore, to get the same voltage boost, the capacitor voltage stress is reduced to a significant extent. The speed control capability of the proposed brushless DC motor drive is compared with that of the conventional ZSI. The proposed ZSI is implemented in MATLAB/Simulink working platform and the output performance is evaluated. Also, the performance of voltage ratio is analysed both by simulation and mathematical models. All these analyses are known to express the innovative features of the proposed system.
Directory of Open Access Journals (Sweden)
U. Marschner
2014-09-01
Full Text Available Two-layer flexure beams often serve as basic transducers in actuators and sensors. In this paper a generalized description of their stimuli-influenced mechanical behavior is derived. For small deflection angles this description includes a multi-port circuit or network representation with lumped elements for a beam part of finite length. A number of coupled finite beam parts model the dynamic behavior including the first natural frequencies of the beam. For piezoelectric and piezomagnetic interactions, reversible transducer models are developed. The piezomagnetic two-layer beam model is extended to include solenoid and planar coils. Linear network theory is applied in order to determine network parameters and to simplify the circuit representation. The resulting circuit model is the basis for a fast simulation of the dynamic system behavior with advanced circuit simulators and, thus, the optimization of the system. It is also a useful tool for understanding and explaining this multi-domain system through basic principles of general system theory.
Steering Control of Wheeled Armored Vehicle with Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
Considering the steering characters of one type of wheeled armored vehicle, a brushless direct current (DC) motor is adapted as the actuator for steering control. After investigating the known algorithms, one kind of algorithm, which combines the fuzzy logic control with the self-adapting PID control and the startup and pre-brake control, is put forward. Then a test-bed is constructed, and an experiment is conducted. The result of experiment confirms the validity of this algorithm in steering control of wheeled armored vehicle with brushless DC motor.
Simulation of Brushless DC Motor using Direct Torque Control
Directory of Open Access Journals (Sweden)
Mrs.G. Kusuma
2014-04-01
Full Text Available This paper deals with modelling of three phases brushless dc motor with MATLAB/SIMULINK software BLDC motor have advantages according to brushless dc motor and induction motor’s. They have improve speed torque charactistics, high efficiency high transient response and small size. It approaches for reducing the torque ripples of BLDC motor using DTC, by using control technique’s ,but present work mainly concentrate on advanced method. The whole drive system is simulated based on the system devices, BLDC motor source inverter, space vector modulation.
Shields-Johnson, Maria E.; Hernandez, John S.; Torno, Cody; Adams, Katherine M.; Wainwright, Marcy L.; Mozzachiodi, Riccardo
2013-01-01
In "Aplysia," repeated trials of aversive stimuli produce long-term sensitization (LTS) of defensive reflexes and suppression of feeding. Whereas the cellular underpinnings of LTS have been characterized, the mechanisms of feeding suppression remained unknown. Here, we report that LTS training induced a long-term decrease in the excitability of…
Sensorless Control of PM Synchronous Motors and Brushless DC Motors
DEFF Research Database (Denmark)
Montesinos, D.; Galceran, Samuel; Blaabjerg, Frede;
2005-01-01
This paper provides a review of the literature addressing sensorless operation methods of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, those me...
Control strategies for brushless doubly fed reluctance machines
Jovanovic, Milutin; Betz, Robert
2001-01-01
Paper presents the development and results of comprehensive comparative analysis of different vector control strategies for performance optimisation of the BDFRM being considered as a viable cost-effective brushless alternative to traditional brush and less reliable solutions in applications with limited variable speed ranges (such as wind turbines). Australian Research Council and EPSRC projects.
Hybrid Adaptive Observer for a Brushless DC Motor
DEFF Research Database (Denmark)
Niemczyk, Piotr; Porchez, Thomas; Bendtsen, Jan Dimon;
2008-01-01
A novel hybrid adaptive observer for Brushless DC Motors (BLDCM) is presented. It uses two current measurements of BLDCM phases to estimate the angle and the speed of the rotor. The observer is designed on the basis of a hybrid model, which is also presented in this paper. The parameters of the o...
Design of Pulse Circuit of Exciting Electromagnetic Ultrasonic%电磁超声脉冲激励电路的设计
Institute of Scientific and Technical Information of China (English)
胡力; 严仍春
2013-01-01
为了解决电磁超声能量转化效率较低、信号微弱的问题,设计了一种电磁超声脉冲激励电路.过零检测电路和单片机实现磁场强度与涡流激发的同步以及脉冲个数的控制；UCC3895芯片产生全桥电路的驱动信号,控制脉冲的频率和占空比；MOSFET管IRFP450构成全桥电路实现信号的功率放大.试验结果表明:该系统的稳定性好,可调节磁场强度,能有效地提高电磁超声能量转化效率.%A method of exciting electrical pulse for electromagnetic ultrasonic has been proposed which was to solve the key problems exist in electromagnetic ultrasonic test, such as low transduction efficiency and weak signal. Synchronization of magnetic field strength and eddy current excitation and the number of pulses were controlled by zero crossing detection circuit and MCU. A drive signal of the full bridge circuit was generated by UCC3895 chip to control the frequency and duty radio of the signal. Power amplification was realized by the full bridge constitute of IRFP450. The experimental results showed that the system had good stability, the magnetic field strength was adjustabled, and the electromagnetic ultrasonic energy conversion efficiency could be effectively improved.
Shen, J.X.; Zhu, Z Q; Howe, D
2004-01-01
The sensorless control of brushless machines by detecting the third harmonic back electromotive force is a relatively simple and potentially low-cost technique. However, its application has been reported only for brushless dc motors operating under normal commutation. In this paper, the utility of the method for the sensorless control of both brushless dc and ac motors, including operation in the flux-weakening mode, is demonstrated.
Directory of Open Access Journals (Sweden)
Volker R Zschorlich
Full Text Available The present study shows evidence for conscious motor intention in motor preparation prior to movement execution. We demonstrate that conscious motor intention of directed movement, combined with minimally supra-threshold transcranial magnetic stimulation (TMS of the motor cortex, determines the direction and the force of resulting movements, whilst a lack of intention results in weak and omni-directed muscle activation. We investigated changes of consciously intended goal directed movements by analyzing amplitudes of motor-evoked potentials of the forearm muscle, flexor carpi radialis (FCR, and extensor carpi radialis (ECR, induced by transcranial magnetic stimulation over the right motor cortex and their motor outcome. Right-handed subjects were asked to develop a strong intention to move their left wrist (flexion or extension, without any overt motor output at the wrist, prior to brain stimulation. Our analyses of hand acceleration and electromyography showed that during the strong motor intention of wrist flexion movement, it evoked motor potential responses that were significantly larger in the FCR muscle than in the ECR, whilst the opposite was true for an extension movement. The acceleration data on flexion/extension corresponded to this finding. Under no-intention conditions again, which served as a reference for motor evoked potentials, brain stimulation resulted in undirected and minimally simultaneous extension/flexion innervation and virtually no movement. These results indicate that conscious intentions govern motor function, which in turn shows that a neuronal activation representing an "intention network" in the human brain pre-exists, and that it functionally represents target specific motor circuits. Until today, it was unclear whether conscious motor intention exists prior to movement, or whether the brain constructs such an intention after movement initiation. Our study gives evidence that motor intentions become aware before
Brushless DC Motor Control System Design Based on DSP2812
Directory of Open Access Journals (Sweden)
Wei Min
2016-01-01
Full Text Available By comparison various control methods currently for permanent magnet brushless DC motor, on the basis of motor principle analysis, a current smallest and most real-time all-digital rare earth permanent magnet brushless DC motor control system is designed. The high-speed digital signal processor DSP2812 is applied as the main control unit. The fuzzy PID control algorithm is used to control rectifier regulator and speed, which the speed and current is double closed loop in the system. The principle of control system, control strategy and software is analyzed in this paper. The system has some features such as less overshoot, rapid response speed, good performance of anti-jamming, simple structure, high control precision, flexible in changing control policies and so on. Validity of the design is verified by prototype test.
Cooling efficiency of a brushless direct current stand fan
Yang, Bin; Schiavon, Stefano; Sekhar, Chandra; Cheong, David; Tham, Kwok Wai; Nazaroff, William W.
2015-01-01
In warm environments, isothermal cooling by deliberately enhanced air movement can maintain thermal comfort using less energy than compressor-based air conditioning. To evaluate the performance of a brushless direct current (DC) stand fan, the cooling fan efficiency (CFE) index was measured in a climatic chamber under four dry-bulb temperatures (24, 26, 28, and 30 °C), six speed In warm environments, isothermal cooling by deliberately enhanced air movement can maintain thermal comfort using l...
Permanent magnet brushless motor control based on ADRC
Directory of Open Access Journals (Sweden)
Li Xiaokun
2016-01-01
Full Text Available Permanent magnet brushless motor is a nonlinear system with multiple variables, the mathematical model of Permanent magnet brushless motor is difficult to establish, and since that the classic PID control is hard to precisely control the motor. Active disturbance rejection control (ADRC technique is a new nonlinear controller which does not depend on the system model. It is starting from the classic PID control, and establishing the loop control system by error negative feedback, the ESO(extended state observer observing system which comes from the observer theory of modern control theory to observe internal and external perturbations. ADRC inherits the advantages of PID with little overshoot, high convergence speed, high accuracy, strong anti-interference ability and other characteristics, and it has a strong disturbance adaptability and robustness as for the uncertainty perturbation and their internal disturbance of control objects. Therefore, This paper attempts to use Active disturbance rejection control(ADRC, in order to improve the control of permanent magnet brushless motor. In this design of control system, the simulation of the system is realized based on MATLAB, and then the discrete control algorithm is transplanted to the embedded system to control the permanent magnet brushless DC motor (PMBLDCM. The control system is implemented on the DSP-F28335 digital signal processor, and the DSP also provides the functions like voltage and current AD sampling, PWM driver generation, speed and rotor position calculation, etc. The simulation and experiment results indicate that, the system has good dynamic performance and anti-disturbance performance.
Brushless DC motor Drive during Speed regulation with Current Controller
Directory of Open Access Journals (Sweden)
Bhikshalu Manchala
2015-04-01
Full Text Available Brushless DC Motor (BLDC is one of the best electrical drives that have increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. Due to the increasing demand for compact & reliable motors and the evolution of low cost power semiconductor switches and permanent magnet (PM materials, brushless DC motors become popular in every application from home appliances to aerospace industry. The conventional techniques for controlling the stator phase current in a brushless DC drive are practically effective in low speed and cannot reduce the commutation torque ripple in high speed range. This paper presents the PI controller for speed control of BLDC motor. The output of the PI controllers is summed and is given as the input to the current controller. The BLDC motor is fed from the inverter where the rotor position and current controller is the input. The complete model of the proposed drive system is developed and simulated using MATLAB/Simulink software. The operation principle of using component is analysed and the simulation results are presented in this to verify the theoretical analysis.
Influence of PWM Modes on Commutation Torque Ripples in Sensorless Brushless DC Motor Control System
Institute of Scientific and Technical Information of China (English)
ZHANGXiang－jun; CHENBo－shi; 等
2001-01-01
This paper introduces four PWM modes used in the sensorless brushless DC motor control system,analyzes their different influences on the commutation torque ripple in detail,and selects the best PWM mode in four given types to reduce commutation torque ripple of Brushless OC( BLDC) motors,Simulation and experimental results show that the selection is correct and practical.
Discussion on the Exciting-branch in the Equivalent Circuit of Transformer%变压器等效电路中励磁支路问题探讨
Institute of Scientific and Technical Information of China (English)
方芳; 王铁军; 王向军
2012-01-01
在我国的“电机学”教材中，变压器等效电路中的励磁支路一般都是采用励磁电阻和励磁电抗串联的形式，而美版的教材中采用的则是电阻与电抗并联的形式。本文在分析这两种等效电路的基础上，将这两种不同的励磁支路形式进行对比，指出并联型的励磁支路中各参数的物理意义更加明晰，更有利于学生的学习和理解。%The exciting-branch in the equivalent circuit of a transformer is always made up of a exciting resistance in series with a exciting reactance in the Chinese textbook. But it is always composed of a exciting resistance in paral- lel with a exciting reactance in the American textbook. Both of the two equivalent exciting-branches are analyzed in this paper. A comparison between the two equivalent exciting-branches shows that the parallel exciting-branch has some advantages over the other one. The physical significance of the parameters in the parallel branch is clearer and it is easier for the students to understand and master.
Institute of Scientific and Technical Information of China (English)
2013-01-01
Aimed at the problem of the trigger line and the silicon controlled rectifier for 590 DC internal excitation in actual use, proposed the application of the bridge rectification circuit instead of the complicated trigger and excitation control circuit in order to achieve the simple structure,voltage stability and low maintenance cost.% 针对590直流调速器内部励磁触发线路及可控硅整流模块在实际使用中的问题，提出应用桥堆整流电路替代复杂的触发与励磁控制线路，使励磁电源控制电路达到结构简单、电压稳定、维护成本低的目的。
A Hybrid Model of a Brushless DC Motor
DEFF Research Database (Denmark)
Bendtsen, Jan Dimon; Hansen, Hans Brink; Kallesøe, Carsten Skovmose
2007-01-01
This paper presents a novel approach to modeling of a Brush-Less Direct Current Motor (BLDCM) driven by an inverter using hybrid systems theory. Hybrid systems combine continuous and discrete (event-based) dynamics, which is exactly the case in an inverter-driven BLDCM. The model presented in this...... work consists of a general automaton with discrete states, combined with a set of continuous dynamic equations describing the electro-mechanical behavior of the motor. One of the significant benefits of this strategy is that the model describes the motor under all possible operating conditions. The...
Improved Rotor Speed Brushless DC Motor Using Fuzzy Controller
Directory of Open Access Journals (Sweden)
Jafar Mostafapour
2015-04-01
Full Text Available A brushless DC (BLDC Motors have advantages over brushed, Direct current (DC Motors and , Induction motor (IM. They have better speed verses torque characteristics, high dynamic response, high efficiency, long operating life, noiseless operation, higher speed ranges, and rugged construction. Also, torque delivered to motor size is higher, making it useful in application where space and weight are critical factors. With these advantages BLDC motors find wide spread application in automotive appliance, aerospace medical, and instrumentation and automation industries This paper can be seen as fuzzy controllers compared to PI control BLDC motor rotor speed has improved significantly and beter result can be achieve.
Control of a high-speed, brushless dc motor driven through a cycloconverter line
Cathey, J. J.; Reesor, D. B.; Weimer, J. A.
Feasibility and concept of designing a high-speed, permanent magnet, brushless dc motor aircraft fuel pump drive using a cycloconverter link is examined. Analytical methods are developed to model the behavior of a three-phase permanent magnetic machine when operated as a self-synchronous motor supplied from a polyphase, variable voltage, variable frequency source through a midpoint cycloconverter link under circulating current free mode of control. A hybrid combination of sinusoidal and dc steady-state analysis methods is utilized to obtain a suitable equivalent circuit of the motor. Study of the motor model is made to establish the nature of the no load MMF angle as a function of current to give a minimum value while assuring proper thyristor commutation. Then, a closed loop control system with an outer loop on speed and an inner loop on current is postulated wherein a proportional plus integral controller is placed in the forward path to assure minimum speed error. A numerical study of performance is presented for speed runup and rundown conditions.
SPEED CONTROL OF BRUSHLESS DC MOTOR ON RESONANT POLE INVERTER USING FUZZY LOGIC CONTROLLER
Directory of Open Access Journals (Sweden)
S. Sivakotiah
2011-10-01
Full Text Available Brushless dc motor has been widely used in drive system and servo control because of its fast response ,high density ,high efficiency ,low inertia ,high reliability ,maintenance free. It is however driven by a hard switching frequency, high switching losses, high electromagnetic interference, high acoustic noise and low efficiency. The rectifier/inverter with a simple commutation circuit to provide zero voltage turn on for the switches and soft turn off for diodes. The converter is intended for high performance, medium power applications requiring bidirectional power flow .A new soft switching inverter has been developed to overcome over voltages and over current problems existing resonant link inverter .This inverter employs a single auxiliary switches. The introduces fuzzy logic based soft switching resonant pole inverter using transformer, which can generates dc link voltages notches during chopping which an minimized the drawback of soft switching, The operation principle and control scheme of the inverter are analyzed and performance of the fuzzy controller is compared with conventional PI controller .The simulation result show that the fuzzy controller is compared with the conventional PI controller.
电路冲激响应数值仿真激励源施加方式研究%Study of Applying the Excitation for Modeling Circuit Impulse Response
Institute of Scientific and Technical Information of China (English)
万靖; 邹军
2011-01-01
As a tool to study the transient behavior of a circuit, the impulse response is of vital importance. In order to obtain the impulse response instead of the ideal impulse excitation which does not exist physically, a second order RLC-series circuit is modeled numerically using the companion model with a Gaussian impulse, a triangle impulse, a trapezoidal impulse and a rectangle impulse excitation respectively. Numerical examples are presented to demonstrate the usability of the algorithm in the paper, The initial states of the circuit resulting from four different excitations are compared with the ideal impulse response.%电路的单位冲激响应是研究电路瞬态性质的重要工具之一。由于理想冲激函数在数值实现上存在困难，为得到电路的冲激响应，本文分别以高斯、三角形、梯形和矩形函数作为替代冲激源，采用伴随模型，对二阶RLC串联电路的暂态响应进行了仿真，比较了在四种不同的激励函数作用下电路的初始状态与理想冲激响应的差异。
Brushless PM Motor Optimization using Bees Algorithm and Finite Element Analysis
Directory of Open Access Journals (Sweden)
Reza Ilka
2011-05-01
Full Text Available Brushless permanent magnet motors play an important role in many applications. Power density and efficiency are two important factors in designing such motors. This paper proposes a novel approach to design a brushless permanent magnet motor based on optimization of a combination of power density and efficiency. First of all, this paper presents the equation related to the design and dimensions of brushless permanent magnet motor. Then, an optimum design based on bees algorithm (BA with the purpose of increasing power density is presented. Finally, Simulation results of a 2-D finite element analysis have well validated the efficiency of the applied method.
An improved iron loss estimation for permanent magnet brushless machines
Fang, D
1999-01-01
This paper presents an improved approach for predicting iron losses in permanent magnet brushless machines. The new approach is based on the fundamental concept that eddy current losses are proportional to the square of the time rate of change of flux density. Expressions are derived for predicting hysteresis and eddy current losses in the stator teeth and yoke. The so-called anomalous or excess losses, caused by the induced eddy current concentration around moving magnetic domain walls and neglected in the conventional core loss calculation, are also included in the proposed approach. In addition, the model is also capable of accounting for the stator skewing, if present. The core losses obtained from the proposed approach are compared with those measured on an existing PM motor at several operating speeds, showing very good agreement. (14 refs).
Disc rotors with permanent magnets for brushless DC motor
Hawsey, Robert A.; Bailey, J. Milton
1992-01-01
A brushless dc permanent magnet motor drives an autonomous underwater vehe. In one embodiment, the motor comprises four substantially flat stators in stacked relationship, with pairs of the stators axially spaced, each of the stators comprising a tape-wound stator coil, and first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and a drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore in which the first shaft is disposed. Two different sets of bearings support the first and second shafts. In another embodiment, the motor comprises two ironless stators and pairs of rotors mounted on opposite sides of the stators and driven by counterrotating shafts.
Study on Dual-redundancy Brushless DC Motor Control System%双余度无刷直流电机控制系统研究
Institute of Scientific and Technical Information of China (English)
李东
2012-01-01
在复杂工况条件下，由于维修不便，对无刷直流电机的可靠性要求较高。双余度无刷直流电机则能较好的解决此问题。本文设计了基于DSP的双余度无刷直流电动机驱动控制系统，详细介绍了系统DSP控制器的硬件电路设计，实现对电动机的位置、速度和电流的检测，给出了系统软件设计方案及控制策略，从而实现对整个系统的控制。结果表明，该控制系统，硬件电路结构简单，系统实时性好，响应快，具有良好的控制性能及动态特性。% Under harsh operating condition, maintenance inconvenience, so the high reliability of brushless DC motor is required. Dual-redundancy brushless DC motor is a good solution to this problem. A control system of dual-redundancy brushless DC motor (BLDCM) based on digital signal processor is studied in this paper. The hardware design solutions of the DSP control er is detailed, then the position, speed and the current of the motor are detected, the software design solutions and the control method for the whole control system are presented. Experimental results show that the dual-redundancy motor system based on one piece of DSP has simple circuit, real-time and rapid response, and the system has good control performance and dynamic characteristic.
Study of Dual-redundancy Brushless DC Motor in Electric Aircraft Braking System%飞机刹车用双余度无刷直流电动机的研究
Institute of Scientific and Technical Information of China (English)
高金行; 全兴源; 戴志勇; 曹杨
2012-01-01
A study of dual redundant brushless DC motor in electric aircraft braking system was given. Based on Ansoft, the motor magnetic circuit was analyzed. The structure parameters were optimized. With the mathematical model of brushless DC motor, the simulation performance was shown. The key technologies of Commutation were analyzed. As shown of experiment, the design is reasonable and correct. Key words; dual redundant brushless DC motor; finite element analysis; performance simulation ; key developing technologies%以全电飞机刹车用双余度无刷直流电动机为研究对象,借助Ansoft软件对电机磁路进行分析计算,优化结构参数,并对其进行性能仿真.重点论述了确保无刷余度电机性能最优的调试关键技术.经过样机性能测试与设计相符,满足使用要求.
Directory of Open Access Journals (Sweden)
Jingang Bai
2012-01-01
Full Text Available A new type of brushless double rotor machine (BDRM is proposed in this paper. The BDRM is an important component in compound-structure permanent-magnet synchronous machine (CS-PMSM systems, which are promising for power-split hybrid electric vehicle (HEV applications. The BDRM can realize the speed adjustment between claw-pole rotor and permanent-magnet rotor without brushes and slip rings. The structural characteristics of the BDRM are described and its magnetic circuit model is built. Reactance parameters of the BDRM are deduced by an analytical method. It is found that the size characteristics of the BDRM are different from those of conventional machines. The new sizing and torque equations are analyzed and the theoretical results are used in the optimization process. Studies of the analytical magnetic circuit and finite element method (FEM model show that the BDRM tends to have high leakage flux and low power factor, and then the method to obtain high power factor is discussed. Furthermore, a practical methodology of the BDRM design is developed, which includes an analytical tool, 2D field calculation and performance evaluation by 3D field calculation. Finally, different topologies of the BDRM are compared and an optimum prototype is designed.
电动自行车用无刷直流电机控制系统设计%Brushless DC Motor of Electric Bicycle Control System Design
Institute of Scientific and Technical Information of China (English)
钟晓伟; 宋蛰存; 许刚
2011-01-01
根据以无刷直流电机为驱动电机的电动自行车工作原理,设计了一种以ATmega16单片机为控制核心的电动自行车用无刷直流电机控制系统,给出了系统详细的硬件电路和软件设计方法.在MATLAB/Simulink环境下仿真得出适当的速度环与电流环调节器参数值.与传统的专用模拟控制器相比,具有更大的灵活性、可靠性,容易实现附加功能和全数字化控制.%According to brushless DC motor-driven electric motor bike working principle, a brushless DC motor of electric bicycle control system based on ATmega16 microcontroller was designed, a detail of hardware circuit and software design methods were given. In MATLAB/Simulink simulation environment to draw the appropriate speed loop and current loop regulator parameters. Compared to the traditional specific analog controller, it had greater flexibility,reliability, also was easy to implement additional features and fully digital control.
两相无槽无刷直流电机的无位置传感器控制%Sensorless control of two-phase slotless brushless DC motor
Institute of Scientific and Technical Information of China (English)
钟德刚; 方浩
2011-01-01
In order to eliminate the shortcomings of brushless DC motor control based on hall sensors and realize the sensorless control of two-phase slotless brushless DC motor,the structure of stator and rotor ,the winding connections of two-phase slotless brushless DC motor and the zero-crossing of back EMF detection method were analyzed. The hardware system and software system designs of two-phase slotless brushless DC motor were presented. The test results indicate the feasibility and stability of control system. A simple control circuit, low cost,less torque ripples and high stability are the advantages of the design presented.%为消除无刷直流电机基于霍尔位置传感器控制存在的缺点,实现两相无槽无刷直流电机的无位置传感器控制,首先在分析了两相无槽无刷直流电机的定、转子结构、绕组连接方式以及反电势过零点检测法的工作原理基础上,论述了两相无槽无刷直流电机无位置传感器控制的硬件系统和软件系统的设计方案,并对两相无刷直流电机进行了试验.试验结果证明了系统的可行性、稳定性.结果表明,该控制方案具有线路简单、成本低、转矩脉动小、系统运行稳定等优点.
Institute of Scientific and Technical Information of China (English)
腾香
2016-01-01
To systematically study on the transient process of RC first-order circuit under the excitation of the sinusoidal signal, the mathematical expression of the complete response, composed of sinusoidal steady com-ponent superimposing on transient component, is derived from the differential equation of the circuit. The over-voltage phenomenon in transient process occurs due to the existence of transient components and initial phase an-gle conditions of sinusoidal excitation signal for producing maximum overvoltage are analyzed. And then the sim-ulation test is explored with Multisim software.%为了系统地研究正弦信号激励下RC一阶电路的暂态过程，从电路的微分方程出发，推导出电路的完全响应是正弦稳态分量与暂态分量相叠加的数学表达式，暂态分量使电路在暂态过程产生过压现象，分析了产生最大过压时正弦激励信号的初相角条件。并用Multisim软件进行了仿真实验测试。
Institute of Scientific and Technical Information of China (English)
欧阳金鑫; 熊小伏
2014-01-01
双馈风电机组的规模化应用使电力系统的故障暂态特性发生变化。为了保障电力系统规划设计和保护控制的顺利实施，必须充分掌握双馈感应发电机(doubly fed induction generator，DFIG)输出短路电流的特征。目前双馈感应发电机的暂态分析尚未计及变流器励磁控制的影响，使双馈风电机组短路电流还难以准确分析和计算。针对DFIG转子侧变流器励磁控制与发电机电磁过程的复杂暂态耦合，通过构建包含变流器调控过程及发电机电磁暂态的转子回路动态模型，重点分析了电网对称短路冲击作用下DFIG的暂态扰动及其传递特性，推导了计及励磁调节作用的DFIG定转子短路电流简化表达式，分析了励磁控制下DFIG短路电流的特征以及控制方式对暂态行为的影响，利用时域仿真验证了理论分析的正确性。%The large-scale application of doubly-fed wind turbines has significantly changed the fault transient characteristics of power systems. The short-circuit current contributed by doubly-fed induction generator (DFIG) should be fully understood to ensure the implementation of the planning and protection of power system. However, the impact of the converter excitation control has not been fully assessed, thus resulting in greater difficulty in the analysis and calculation of short-circuit current. This study presents a detailed analysis of short-circuit current of a DFIG, with focus on the complex coupling between the excitation control and electromagnetic process. The transient disturbances and their transitive relation in a DFIG under symmetrical short circuit are analyzed by constructing the dynamic model of rotor circuit. The expressions of rotor and stator short-circuit currents are deduced for the simplified calculation and analytical analysis. The characteristics of the short-circuit current of DFIG under the excitation control are analyzed and the impacts of
高速永磁无刷电机设计与控制系统研究%High-speed permanent magnet motor design and control system of brushless
Institute of Scientific and Technical Information of China (English)
郑睿鹏
2015-01-01
永磁无刷电机具有结构简单、无励磁损耗、效率高等特点，适合高速场合。目前，高速永磁无刷电机已经在一些电动汽车中得到实际应用，并且在分布式发电供电系统中显示了其价值和重要性。通过对高速永磁无刷电机设计的关键性问题的探讨、对高速永磁无刷电机控制系统的研究得出，高速电机的转速非常高，而且其功率的密度非常大，其几何尺寸小于其输出功率相同的低速电机，这些特征使得它在工业领域受到了广泛的关注和应用。%Permanent magnet brushless motor has a simple structure , no excitation loss, high efficiency, suitable for high speed applications. Currently, high-speed permanent magnet brushless motor has been applied in a number of electric vehicles, and has demonstrated its value and importance in distributed power generation and distribution systems. By discussing the key issues of high-speed permanent magnet brushless motor design, the study of high-speed permanent magnet brushless motor control system derived, high-speed motor speed is very high, and its power density is very large, and its geometry is less than its the same output power low-speed motor, these features make it in the industrial sector has been widespread concern and applications.
基于DSP控制的纯电动汽车无刷直流电动机%Brushless Direct Current Motor Based on DSP Control on Pure Electric Vehicle
Institute of Scientific and Technical Information of China (English)
吴敏
2011-01-01
无刷直流电动机是一种高性能的电动机，它具有结构简单、运行可靠、维护方便、运行效率高、无励磁损耗、运行成本低和调速性能好等优点，因此，它在电动汽车上的应用与日俱增．对无刷直流电动机控制的优化是人们一直期待解决的问题。文章设计了利用TMS320LF2407DSP控制器构成的无刷直流电动机的无位置传感器控制的系统硬件和系统软件，实现了对无位置传感器无刷直流电动机的优化控制，试验证明了该方法的正确性和有效性。%Brushless direct current motor is a type of motor with high performance and many advantages, including simple structure, reliable operation, convenient maintenance, high efficiency, non-excitation loss, low cost and good performance of speed governing. Therefore, its application on electric vehicles has increased. People have been looking forward to the solution to the optimization of the control of brushless direct current motor. This paper designs the eontrolling system＇s hardware and software for no-position sensor on the brushless current motor with the structure of TMS320LF2407 DSP controller, which optimized the brushless current motor with no-position sensor. The test also proves the correctness and effectiveness of this method.
Dynamic modeling of brushless dc motors for aerospace actuation
Demerdash, N. A.; Nehl, T. W.
1980-11-01
A discrete time model for simulation of the dynamics of samarium cobalt-type permanent magnet brushless dc machines is presented. The simulation model includes modeling of the interaction between these machines and their attached power conditioners. These are transistorized conditioner units. This model is part of an overall discrete-time analysis of the dynamic performance of electromechanical actuators, which was conducted as part of prototype development of such actuators studied and built for NASA-Johnson Space Center as a prospective alternative to hydraulic actuators presently used in shuttle orbiter applications. The resulting numerical simulations of the various machine and power conditioner current and voltage waveforms gave excellent correlation to the actual waveforms collected from actual hardware experimental testing. These results, numerical and experimental, are presented here for machine motoring, regeneration and dynamic braking modes. Application of the resulting model to the determination of machine current and torque profiles during closed-loop actuator operation were also analyzed and the results are given here. These results are given in light of an overall view of the actuator system components. The applicability of this method of analysis to design optimization and trouble-shooting in such prototype development is also discussed in light of the results at hand.
James Webb Space Telescope Deployment Brushless DC Motor Characteristics Analysis
Tran, Ahn N.
2016-01-01
A DC motor's performance is usually characterized by a series of tests, which are conducted by pass/fail criteria. In most cases, these tests are adequate to address the performance characteristics under environmental and loading effects with some uncertainties and decent power/torque margins. However, if the motor performance requirement is very stringent, a better understanding of the motor characteristics is required. The purpose of this paper is to establish a standard way to extract the torque components of the brushless motor and gear box characteristics of a high gear ratio geared motor from the composite geared motor testing and motor parameter measurement. These torque components include motor magnetic detent torque, Coulomb torque, viscous torque, windage torque, and gear tooth sliding torque. The Aerospace Corp bearing torque model and MPB torque models are used to predict the Coulomb torque of the motor rotor bearings and to model the viscous components. Gear tooth sliding friction torque is derived from the dynamo geared motor test data. With these torque data, the geared motor mechanical efficiency can be estimated and provide the overall performance of the geared motor versus several motor operating parameters such as speed, temperature, applied current, and transmitted power.
The special brushless synchronous motors for oil field pumps
International Nuclear Information System (INIS)
Full text : This paper deals with : 1) Oil and gas industries mechanisms severe duties and main demands to their field quipment; 2) technical and economical substantiate of pumps induction motors (IM) replacement by eliable almost like IM special, brushless synchronous motor (SBSM) as energy saving, tability, reliability and even ecology improving arrangement; 3) a peculiar approach during the project and construction, work of the SBSM (with the simplest constant current exiting system) to get self-stabilizing effect cost under wide range cycling torque; 4) substantiate supporting oilfield experiments and computer-assisted electrodynamic (mechatronic) lab model's studies including IM and SBSM dynamic stability analyses in conditions of supply voltage wide fluctuations and extensive cyclic moment if the spare parts. The calculated SBSM production cost is equal to 130-150 percent of IM cost. After intensive lab studies and long-run field applications SBSM was recommended for industry to replace obsolete and old IM and to plan this type SBSM for new sucker-rod oil pumps (SRP), even if the real cost of the SBSM is double of the IM cost
Energy Technology Data Exchange (ETDEWEB)
MacMillan, P.N.
1985-06-01
Recent improvements in rare earth magnets have made it possible to construct strong, lightweight, high-horsepower DC motors. This has occasioned a reassessment of electromechanical actuators as alternatives to comparable pneumatic and hydraulic systems for use as flight-control actuators for tactical missiles. A dynamic equivalent circuit model for the analysis of a small four pole brushless DC motor fed by a transistorized power conditioner utilizing high speed switching power transistors as final elements is presented. The influence of electronic commutation on instantaneous dynamic motor performance is particularly demonstrated and good correlation between computer simulation and typical experimentally obtained performance data is achieved. The model is implemented in CSMP language and features more accurate air gap flux representation over previous work. Hall-effect sensor rotor position feedback is simulated. Both constant and variable-air-gap flux is modeled and the variable flux model treats the flux as a fundamental and one harmonic.
Institute of Scientific and Technical Information of China (English)
赵朝会; 秦海鸿; 严仰光
2009-01-01
针对电励磁爪极发电机效率低、永磁爪极发电机磁场调节困难的问题,提出了一种串联磁路混合励磁爪极同步发电机,利用磁路计算方法和三维有限元的分析研究了这种新型电机各部分的磁密大小,确定了合适的极对数和合理的磁钢厚度,探讨了这种新型电机的空载特性、外特性和调节特性.研究表明:串联磁路混合励磁爪极发电机合适的极对数为2,且磁钢厚度存在一个较为合理的优化值.相对于电励磁爪极发电机,它实现了励磁电流的双向控制;相对于永磁爪极发电机它使得输出电压可调,在更宽的负载范围内实现了输出电压的恒定.在参数相同的情况下,与电励磁爪极发电机相比,该电机具有更高的气隙磁密和功率密度.%To solve the low efficiency of electric excitation claw-pole synchronous generator(EECPSG) and regulate the magnetic field of permanent magnet (PM) claw-pole synchronous generator(PMCPSG), a novel hybrid excitation claw-pole synchronous generator(HECPSG) with magnetic circuit series connection is proposed. Through the simulation study on the generator using the calculation method for magnetic circuit and 3-D finite element method(FEA), the appropriate magnet thickness and the number of pole-pairs for the proposed generator are determined. Its off-loading characteristics, load characteristics, and regulation behaviors are investigated. The study shows that the appropriate number of pole-pairs in HECPSG with series magnetic circuits is two, and there exists an optimum magnet thickness.Compared to EECPSG, HECPSG realizes dual-directional control to the excitation current. Moreover, the generator can adjust the output voltage and keep the output voltage stable in a broad load range. Under the condition of same parametes, the motor has higer air-gap flux density and power density.
Development of a Practical Low-Cost µC based Brushless DC Motor Controller using Proteus
Directory of Open Access Journals (Sweden)
Y. L. Karnavas
2012-09-01
Full Text Available Simulation, design and prototype construction of a low cost three phase permanent magnet (PM brushless DC (BLDC motor controller for low power applications is studied in this paper. The drive circuitry is based on the PIC16F877A microcontroller (µC, which –among others- performs pulse width modulation (PWM control for a 6-step, 120-degree trapezoidal PM BLDC motor drive. The specific processor is a widely used one and its characteristics are judged excellent in conjunction with its low cost. The prototype controller developed can perform rotation direction control, commutation sequence, speed control and reading Hall sensor signals. The controlling technique chosen is a “sensored type” one. The main reason for that, except control simplicity is the need for both low-speed and high-speed applications. The application of Proteus Virtual System Modelling (VSM software is also introduced in the paper. This software is used as a real-time simulation tool, in order to verify the performance of the BLDC motor drive, prior to its hardware implementation. Through virtual simulation of all the components used, the relevant results can be analyzed and monitored. Verification of the experimental results and validation of the simulated circuit has been done through the comparison of the results.
Demonstrations with an "LCR" Circuit
Kraftmakher, Yaakov
2011-01-01
The "LCR" circuit is an important topic in the course of electricity and magnetism. Papers in this field consider mainly the forced oscillations and resonance. Our aim is to show how to demonstrate the free and self-excited oscillations in an "LCR" circuit. (Contains 4 figures.)
Improved Analytical Model of a Permanent-Magnet Brushless DC Motor
Kumar, P.; Bauer, P.
2008-01-01
In this paper, we develop a comprehensive model of a permanent-magnet brushless DC (BLDC) motor. An analytical model for determining instantaneous air-gap field density is developed. This instantaneous field distribution can be further used to determine the cogging torque, induced back electromotive
Novel Motion Sensorless Control of Single Phase Brushless D.C. PM Motor Drive, with experiments
DEFF Research Database (Denmark)
Lepure, Liviu Ioan; Boldea, Ion; Andreescu, Gheorghe Daniel;
2010-01-01
A motion sensorless control for single phase permanent magnet brushless d.c. (PM-BLDC) motor drives, based on flux integration and prior knowledge of the PM flux/position characteristic is proposed here and an adequate correction algorithm is adopted, in order to increase the robustness to noise...
Directory of Open Access Journals (Sweden)
A.V. Matyuschenko
2015-03-01
Full Text Available By means of JMAG-Designer 12 the author performed a comparative analysis of the calculation of the EMF, cogging torque and electromagnetic torque of brushless motor with permanent magnets in two-dimensional and three-dimensional formulation of the problem.
Rotor position sensing in brushless ac motors with self-shielding magnets using linear Hall sensors
Zhu, Z. Q.; Shi, Y. F.; Howe, D.
2006-04-01
This paper investigates the use of low cost linear Hall sensors for rotor position sensing in brushless ac motors equipped with self-shielding magnets, addresses practical issues, such as the influence of magnetic and mechanical tolerances, temperature variations, and the armature reaction field, and describes the performance which is achieved.
Comparison of solar panel cooling system by using dc brushless fan and dc water
Irwan, Y. M.; Leow, W. Z.; Irwanto, M.; M, Fareq; Hassan, S. I. S.; Safwati, I.; Amelia, A. R.
2015-06-01
The purpose of this article is to discuss comparison of solar panel cooling system by using DC brushless fan and DC water pump. Solar photovoltaic (PV) power generation is an interesting technique to reduce non-renewable energy consumption and as a renewable energy. The temperature of PV modules increases when it absorbs solar radiation, causing a decrease in efficiency. A solar cooling system is design, construct and experimentally researched within this work. To make an effort to cool the PV module, Direct Current (DC) brushless fan and DC water pump with inlet/outlet manifold are designed for constant air movement and water flow circulation at the back side and front side of PV module representatively. Temperature sensors were installed on the PV module to detect temperature of PV. PIC microcontroller was used to control the DC brushless fan and water pump for switch ON or OFF depend on the temperature of PV module automatically. The performance with and without cooling system are shown in this experiment. The PV module with DC water pump cooling system increase 3.52%, 36.27%, 38.98%in term of output voltage, output current, output power respectively. It decrease 6.36 °C compare than to PV module without DC water pump cooling system. While DC brushless fan cooling system increase 3.47%, 29.55%, 32.23%in term of output voltage, output current, and output power respectively. It decrease 6.1 °C compare than to PV module without DC brushless fan cooling system. The efficiency of PV module with cooling system was increasing compared to PV module without cooling system; this is because the ambient temperature dropped significantly. The higher efficiency of PV cell, the payback period of the system can be shorted and the lifespan of PV module can also be longer.
Zhiyi Song; Chengde Tong; Jingang Bai; Qian Wu; Ping Zheng
2013-01-01
A novel brushless double rotor machine (BDRM) is proposed in this paper. The BDRM is an important component in the brushless compound-structure permanent-magnet synchronous machine (CS-PMSM) system, which is a promising technology for power-split hybrid electric vehicle (HEV) applications. Compared with common double rotor machines, the brushes and slip rings required by rotating winding have been omitted in the BDRM, thus there are no such problems as maintenance, friction losses and so fort...
Development of patent technology for brushless doubly fed motor%无刷双馈电机专利技术发展
Institute of Scientific and Technical Information of China (English)
张颖超
2015-01-01
近年来，作为可再生能源的风力发电受到了全球范围的广泛关注，人们越来越重视适用于风力发电的新型电机，无刷双馈电机以其简单的结构，高可靠性，具有异步和同步电机两种电机的综合特点，通过控制激磁绕组的电压和频率易于实现变速恒压恒频发电，是一种适合风力发电运行环境的新型电机。本文主要以DWPI、SIPOABS专利数据库以及CNTXT数据库中的检索结果为分析样本，从专利文献的视角对无刷双馈电机的发展进行了全面的统计分析，总结了与无刷双馈电机相关的国内和国外专利的申请趋势、主要申请人分布以及其转子结构的发展路线做了一定的分析，并从中得到一定的规律。%In recent years,wind power as the renewable energy by widespread concern in the global scope, people pay more and more attention to applicable to wind power as a new kind of motor, brushless doubly fed machine with its simple structure,high reliability,with the comprehensive characteristic of asynchronous and synchronous motor,two kinds of motor,by controlling the voltage and frequency of the excitation winding is easy to realize the variable speed constant frequency and constant voltage power,is a suitable for wind power generation operating environment as a new kind of motor.This paper mainly to DWPI,SIPOABS patent database and CNTXT database retrieval results for the analysis of the sample,from the patent literature from the perspective of the development of brushless doubly fed machine were comprehensive statistical analysis,summarized and brushless doubly fed machine related domestic and foreign patent application trend, mainly distributed in the applicant and the rotor structure of the development route do some analysis, and the obtained certain rules.
Energy Technology Data Exchange (ETDEWEB)
Biwersi, Stephan; Tavernier, Stephan; Equoy, Samuel [Moving Magnet Technologies (MMT), Besancon (France)
2012-12-01
Moving Magnet Technologies (MMT) from Besancon in France has developed a highly efficient brushless DC motor that is especially suitable for use in electrically supported compressors. It helps to further minimise so-called turbo lag in supercharged internal combustion engines. The following report presents technical details of the electric motor and practical results in combination with an electrically driven compressor. MMT was supported by Swissauto in designing the supercharging system.
A novel left ventricular assist device with impeller pump and brushless motor compacted in one unit
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The impeller pump we developed has assisted the circulation of calves for two months, but further improvements to solve the problems of bearing wear and thrombosis along the bearing are desirable. Thus we have designed a new left ventricular assist device (LVAD) with impeller pump and brushless motor compacted in one unit, for which a ceramic bearing and a purge system through the bearing have been devised. The first experiments indicate that this new device could prospectively work for more than one year.
Short-circuit forces in power lines and substations.
Lilien, Jean-Louis; Goel, Anand
2009-01-01
This chapter discusses short-circuit oscillations in power lines. Short-circuit currents generate electromagnetic forces on the conductors, exciting short-circuit oscillations. Since the short-circuit periods are very short, the short-circuit forces in single conductor overhead lines are usually low because of the large phase spacing. However these forces may have considerable impact on distribution lines due to the change in phase spacing during short-circuit occurrences. For bundle conducto...
Design and Optimization of Permanent Magnet Brushless Machines for Electric Vehicle Applications
Directory of Open Access Journals (Sweden)
Weiwei Gu
2015-12-01
Full Text Available In this paper, by considering and establishing the relationship between the maximum operating speed and d-axis inductance, a new design and optimization method is proposed. Thus, a more extended constant power speed range, as well as reduced losses and increased efficiency, especially in the high-speed region, can be obtained, which is essential for electric vehicles (EVs. In the first step, the initial permanent magnet (PM brushless machine is designed based on the consideration of the maximum speed and performance specifications in the entire operation region. Then, on the basis of increasing d-axis inductance, and meanwhile maintaining constant permanent magnet flux linkage, the PM brushless machine is optimized. The corresponding performance of the initial and optimal PM brushless machines are analyzed and compared by the finite-element method (FEM. Several tests are carried out in an EV simulation model based on the urban dynamometer driving schedule (UDDS for evaluation. Both theoretical analysis and simulation results verify the validity of the proposed design and optimization method.
SIMULATION AND IMPLEMENTATION OF CURRENT CONTROL OF BRUSHLESS DC MOTOR BASED ON A COMMON DC SIGNAL
Directory of Open Access Journals (Sweden)
J.Karthikeyan
2010-06-01
Full Text Available The objective of this project is to build a simple current controlled modulation technique for brushless dc motors. In electric traction and most other applications, a wide range of speed and torque control of the electric motor is required. The dc machine fulfills these requirements, but the dc machine requires constant maintenance. But the brushless permanent magnet motors do not have brushes and so they require less maintenance only. Brushless dc motors are widely used in applications which require wide range of speed and torque control because of its low inertia, fast response, high reliability and maintenance free. This current controlled technique is based on the generation of quasi- square wave currents using only one controller for the three phases. The current control strategy uses a triangular carrier for the power transistors which is simpler and more accuratethan any other options. The advantages of this technique are: a The stator currents are completely characterized by their maximum amplitude , b The three phases are controlled with the same dc component , and then the phase currents are kept at exactly the same magnitude I max, c The dc link current measurement is not required .d phase currents are kept balanced and phase over currents are eliminated.
Sarpeshkar, Rahul; Watts, Lloyd; Mead, Carver
1992-01-01
Neural networks typically use an abstraction of the behaviour of a biological neuron, in which the continuously varying mean firing rate of the neuron is presumed to carry information about the neuron's time-varying state of excitation. However, the detailed timing of action potentials is known to be important in many biological systems. To build electronic models of such systems, one must have well-characterized neuron circuits that capture the essential behaviour of real neur...
MUTLU, Reşat
2015-01-01
The memristor is a new-found circuit element and its applications in programmable circuits are also under study. Analysis of most of its combinations with other circuit elements such as resistors, capacitors, and inductors does not exist. In this work, a TiO$_{2}$ memristor model with linear dopant drift speed is used and the solution of a TiO$_{2}$ memristor and capacitor series circuit driven by a constant voltage source is given. It is then used to analyze a novel M-C oscillator circuit. I...
Giant Magnetostrictive Material Exciter for Panel Loudspeaker
Institute of Scientific and Technical Information of China (English)
WANG Rui; ZHANG Yong-fa
2008-01-01
The exciter component in a panel loudspeaker has a profound effect on the overall performance of the system.The equivalent circuit analysis of the combination of giant magnetostrictive material exciter and distributed mode panel is introduced and how exciter parameters influence panel lffudspeaker's performance is discussed.NumericaI predictions are given in order to show how these influences are manifested.
POSITION CONTROL OF BRUSHLESS DC MOTOR BASED ON DIGITAL SIGNAL PROCESSING
Directory of Open Access Journals (Sweden)
Çetin GENÇER
2006-01-01
Full Text Available Brushless DC Motors (BLDC have been used widely high performance control systems which are depended on to development of power electronic and control technology. In these motors to fed commutated supply, the control of position without oscilation has been required. In this study, position control of BLDC with digital signal processing has been implemented by a proportional-derivative (PD controller because of its simple structure. It has been seen that the controller which is proposed from simulation and experimental studies, has a quick dynamic responce with nonoscillation.
Aspects Concerning the Torque Ripple Control of the Brushless DC Motor
Directory of Open Access Journals (Sweden)
BALUTA, G.
2013-05-01
Full Text Available This paper deals with two advanced numerical structures to control the electromagnetic torque ripple of Brushless Direct Current Motors (BLDCM, indirectly achieved by phase currents control and directly by the Direct Torque Control (DTC technique. In DTC there was implemented an observer to increase the rudimentary transducer resolution, containing three Hall Effect sensors. The experimental results describe the evolution of torque in both situations of control and are obtained by applying a control strategy for an electric drive system with BLDCM with trapezoidal Back-EMF in Two-Phase Mode.
Novel Position and Speed Estimator for PM Single Phase Brushless D.C. Motor Drives
DEFF Research Database (Denmark)
Lepure, Liviu I.; Andreescu, Gheorghe-Daniel; Iles, Doris;
2010-01-01
the sensitivity to accuracy of flux linkage estimation. A speed and current close loop control is employed based on the Hall signal and the motor is controlled at different speeds in order to validate the proposed estimation algorithm with satisfying results. The position correction effect is analyzed......A novel position and speed estimator for single phase permanent magnet brushless d.c. (PMBLDC) motor drives, based on flux integration and prior knowledge of ΨPM (θ) is proposed here and an adequate correction algorithm is adopted in order to increase the robustness to noise and to reduce...... by examination of improvements in both position error and speed pulsations....
Numerical and Experimental Investigation of Heat Flow in Permanent Magnet Brushless DC Hub Motor
DEFF Research Database (Denmark)
Fasil, Muhammed; Plesner, Daniel; Walther, Jens Honore;
2014-01-01
This paper investigates the heat dissipation in the hub motor of an electric two-wheeler using lumped parameter (LP), finite element (FE) and computational fluid dynamic (CFD) models. The motor uses external rotor permanent magnet brushless DC topology and nearly all of its losses are generated...... the internal and the external flow as well as the convective heat transfer of the hub motor. Finally, an optimization study of the hub motor has been carried out using the CFD model to improve heat transfer from the stator....
Application of Full-Order and Simplified EKFs to Sensorless PM Brushless AC Machines
Institute of Scientific and Technical Information of China (English)
Xi Zhu; Zi-Qiang Zhu; David Howe
2005-01-01
This paper em ploys an extended Kalman filter (EKF) to estimate the rotor position and speed of a vector controlled surface-mounted permanent magnet (PM) brushless AC (BLAC) motor from measured terminal voltages and currents only. Both full-order and simplified EKFs are employed and their simulated performance capabilities are compared.Excellent agreement is achieved between estimated and commanded results. The EKF is also employed to identify the stator flux-linkage due to the PMs, which is influenced by temperature variation and magnetic saturation.
Sharkh, S.M.; Lai, S. H.
2009-01-01
This paper discusses the analysis and design of a very thin slotless PM brushless motor whose stator laminations are manufactured from a single strip of steel that is edge wound into a spiral (like a “Slinky”) and then fitted over the windings that are preformed on the outside surface of a non-conducting former. Analytical and finite element analysis (FEA) are used to determine the constrained optimum dimensions of a motor used to drive a rim driven thruster in which the motor rotor is fitted...
The Application of Parameter Space Design Method for Generator Excitation Control
Iki, Hiroyuki; Yoshimura, Shyuta; Uriu, Yosihisa
Recently, control engineering changes from classical control theory to modern control theory, and analogue to digital. However, as a matter of fact, the sensitivity adjustment of the parameters using Bode diagram require many time and works. In this paper, the tool of Matlab/Simulink that adjusted the AVR control parameter of the PI control type brushless and Thyristor excitation method by using the technique for based on the parameter space planning method by QE was made. Moreover, the adjustment of the sensitivity parameter of the excitation control method intended for the dynamic stability level area in Single Machine Infinite Bus is examined with the tool.
Multiple Replicas of Block Copolymer Thin Films from a Brushless Organosilicate Substrate
Suh, Hyo Seon; Yoon, Hyunsik; Char, Kookheon
2011-03-01
The chain end-grafted polymer brushes or cross-linked polymer mats have typically been utilized as the surface modification layers to induce the perpendicular orientation of block copolymer (BCP) thin films. Instead of such polymer-based approaches, we have recently introduced a new concept to control the BCP orientation using the brushless organosilicate (OS) substrates, whose surface energy can be finely tuned with thermal treatment. In this brushless case, the BCP chains do not penetrate into the underlying hard OS substrates during thermal annealing of BCP films, therefore, the BCP chains at the interface have no entangled structure with fairly weak adhesion of BCP films against the substrate. Owing to such weak adhesion of BCP films against the OS substrate, the perpendicularly oriented BCP film on a neutral OS substrate could be easily peeled off and transferred to a UV-curable resin applied onto the BCP film. The OS substrate after the peel-off process of a BCP film could regenerate the perpendicularly oriented BCP films since the surface energy of the OS substrate remains intact during the peel-off process. Furthermore, the direct-assembled BCP films on chemically patterned OS substrates could also be peeled off and transferred on to a UV-curable resin, allowing us to produce multiple replicas of direct-assembled BCP thin films from a single chemically patterned OS substrate.
Directory of Open Access Journals (Sweden)
E. Kaliappan
2012-01-01
Full Text Available Problem statement: In this study, a simplified modeling and experimental analysis of Permanent Magnet Brushless DC (PMBLDC motors for Sensorless operation using MATLAB/SIMULINK. This model provides a mechanism for monitoring and controlling the voltage, current, speed and torque response. Approach: BLDC motor is modeled as sub-blocks. The inverter and switching function are implemented as S-function builder block. The Sensorless scheme employs direct back emf based zero crossing detection technique. Results: The proposed model with Sensorless control technique with back emf zero crossing detection is tested in the BLDC Motor and the performance was evaluated. The simulated and experimental results show that the proposed modeling works quite well during starting and running conditions. Conclusion/Recommendation: The developed model consists of several independent sub-blocks, that can be used in the modeling of Permanent Magnet Sinusoidal Motor and induction motor. Hence the developed simulation model is a design tool to study the dynamic behavior of Sensorless Controlled Brushless DC Motor.
Optimization of PID Controller for Brushless DC Motor by using Bio-inspired Algorithms
Directory of Open Access Journals (Sweden)
Sanjay Kr. Singh
2014-02-01
Full Text Available This study presents the use and comparison of various bio-inspired algorithms for optimizing the response of a PID controller for a Brushless DC Motor in contrast to the conventional methods of tuning. For the optimization of the PID controllers Genetic Algorithm, Multi-objective Genetic Algorithm and Simulated Annealing have been used. PID controller tuning with soft-computing algorithms comprises of obtaining the best possible outcome for the three PID parameters for improving the steady state characteristics and performance indices like overshoot percentage, rise time and settling time. For the calculation and simulation of the results the Brushless DC Motor model, Maxon EC 45 flat ф 45 mm with Hall Sensors Motor has been used. The results obtained the optimization using Genetic Algorithms, Multi-objective Genetic Algorithm and Simulated Annealing is compared with the ones derived from the Ziegler-Nichols method and the MATLAB SISO Tool. And it is observed that comparatively better results are obtained by optimization using Simulated Annealing offering better steady state response.
Directory of Open Access Journals (Sweden)
Milutin G. Jovanović
2006-12-01
Full Text Available The brushless doubly-fed machine (BDFM allows the use of a partially rated inverter and represents an attractive cost-effective candidate for variable speed applications with limited speed ranges. In its induction machine form (BDFIM, the BDFM has significant rotor losses and poor efficiency due to the cage rotor design which makes the machine dynamic models heavily parameter dependent and the resulting controller configuration complicated and difficult to implement. A reluctance version of the BDFM, the brushless doubly-fed reluctance machine (BDFRM, ideally has no rotor losses, and therefore offers the prospect for higher efficiency and simpler control compared to the BDFIM. A detailed study of this interesting and emerging machine is very important to gain a thorough understanding of its unusual operation, control aspects and compromises between optimal performance and the size of the inverter and the machine. This paper will attempt to address these issues specifically concentrating on developing conditions for various control properties of the machine such as maximum power factor, maximum torque per inverter ampere and minimum copper losses, as well as analysing the associated trade-offs.
Developing Micro DC-Brushless Motor Driver and Position Control for Fiber Positioners
Jenni, Laurent; Makarem, Laleh; Kneib, Jean-Paul; Gillet, Denis; Bleuler, Hannes; Bouri, Mohamed; Prada, Francisco; De Rivera, Guillermo; Sanchez, Justo
2014-01-01
In the large-scale, Dark Energy Spectroscopic Instrument (DESI), thousands of fiber positioners will be used. Those are robotic positioners, with two axis, and having the size of a pen. They are tightly packed on the focal plane of the telescope. Dedicated micro-robots have been developed and they use 4mm brushless DC motors. To simplify the implementation and reduce the space occupancy, each actuator will integrate its own electronic control board. This board will be used to communicate with the central trajectory generator, manage low level control tasks and motor current feeding. In this context, we present a solution for a highly compact electronic. This electronic is composed of two layers. The first is the power stage that can drive simultaneously two brushless motors. The second one consists of a fast microcontroller and deals with different control tasks: communication, acquisition of the hall sensor signals, commutation of the motors phases, and performing position and current regulation. A set of di...
Developing micro DC-brushless motor driver and position control for fiber positioners
Jenni, Laurent; Hörler, Philipp; Makarem, Laleh; Kneib, Jean-Paul; Gillet, Denis; Bleuler, Hannes; Bouri, Mohamed; Prada, Francisco; De Rivera, Guillermo; Sanchez, Justo
2014-07-01
In the large-scale, Dark Energy Spectroscopic Instrument (DESI), thousands of fiber positioners will be used. Those are robotic positioners, with two axis, and having the size of a pen. They are tightly packed on the focal plane of the telescope. Dedicated micro-robots have been developed and they use 4mm brushless DC motors. To simplify the implementation and reduce the space occupancy, each actuator will integrate its own electronic control board. This board will be used to communicate with the central trajectory generator, manage low level control tasks and motor current feeding. In this context, we present a solution for a highly compact electronic. This electronic is composed of two layers. The first is the power stage that can drive simultaneously two brushless motors. The second one consists of a fast microcontroller and deals with different control tasks: communication, acquisition of the hall sensor signals, commutation of the motors phases, and performing position and current regulation. A set of diagnostic functions are also implemented to detect failure in the motors or the sensors, and to sense abnormal load change that may be the result of two robots colliding.
无刷直流电动机双模式控制%Dual Mode Control for Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
赵建勇; 许林荣; 徐交建
2012-01-01
在分析电机运行原理和应用要求的基础上,引用基于新型逆变器的无刷直流电动机双模式控制方法,设计出无刷直流电动机双模式控制器,基速以下采用双闭环控制方法,基速以上采用弱磁扩速控制方法.仿真和实验验证该方案可行,实现无刷直流电动机在宽速度范围内稳定工作.%Dual mode control method based on a new inverter for brushless DC motor was cited by analyzing the operation principle of brushless DC motor and application requirements. Dual mode controller for brushless DC motor was designed, which used dual closed loop control when motor was running below base speed and field-weakening control when motor was running above base speed. The simulation and experiment results show that brushless DC motor can operate in a wide speed range.
Energy Technology Data Exchange (ETDEWEB)
Muenchow, Frank [Federal-Mogul, Bad Camberg (Germany). Geschaeftsbereich Vehicle Safety and Protection; Harvey, Richard; Richards, Michael [Federal-Mogul Corporation, Logansport, IN (United States). Business Unit Vehicle Safety and Protection
2012-03-15
Electrifying components in commercial vehicles can be a challenge. High vibration levels, for instance, amplify carbon brush and commutator erosion in a conventional electric motor. To offer a solution Federal-Mogul has developed the brushless fuel pump. This BLDC pump has successfully passed 10,000 h of operation in B100 fuel. (orig.)
Nelson, Jane B.
1998-01-01
Describes a research-based activity for high school physics students in which they build an LC circuit and find its resonant frequency of oscillation using an oscilloscope. Includes a diagram of the apparatus and an explanation of the procedures. (DDR)
DEFF Research Database (Denmark)
2010-01-01
A switch-mode power circuit comprises a controllable element and a control unit. The controllable element is configured to control a current in response to a control signal supplied to the controllable element. The control unit is connected to the controllable element and provides the control...
Institute of Scientific and Technical Information of China (English)
诸自强
2008-01-01
The torque-speed characteristics of brushless motor having an interior permanent magnet rotor and a sinusoidalback-emf waveform are compared experimentally when it is operated in brushless AC (BLAC) mode and brushless DC(BLDC) modes with both 2-phase, 120° conduction (BLDC-120) and 3-phase,180° conduction (BLDC-180).Particularemphasis is on high-speed,six-step voltage controlled,flux-weakening operation.h is shown that for EV/HEV applications,even for interior PM brushless motors which have sinusoidal back-emf waveforms,in order to achieve maximum torque perampere capability over wide operation speed range,it is advantageous to employ a hybrid operation mode-BLAC operationin the constant torque region and six-step voltage control (BLDC-180 operation, together with current phase control) inthe flux-weakening region.
Directory of Open Access Journals (Sweden)
Rehan Jamil
2013-11-01
Full Text Available An Integral part of generator is Excitation System and new technology of Excitation System has been developed utilizing a power sources. The most important a portion of electric power system is synchronous generator due to it is the source of electrical energy and energy transformation is possible only when generator excitation exists. The generator excitation systems work when generator excitation system operates a dc charge to the generator heads to energize the field of magnetic around them to enable the electricity that should be generated. There are brushless and brush-type exciters and generators are built in exciters or charge can be established from any external source. This paper presents the control and configuration of synchronous generator excitation system as current mainstream technology, which is widely designed for feeding of turbo generator excitation winding with auto- regulated DC in generator operation, control normal and emergency modes. In this paper discuss appended on excitation system models of synchronous generator and emphasis on drawbacks, different possibilities to regulate generator excitation, de-excitation systems and overvoltage Protection with special newly developed nonlinear system regulation. And also append short descriptions of functions, compositions, Structure and Working Principle of Generator Excitation System.
Yan LIU; Wang, Xu; Xing, Yan
2013-01-01
With the rapid growth of an AC adjusted speedsystem application, it is necessary to controland reduce harmonic pollution since theproblem brought about by the device of powerelectronics not only blocks the development ofpower electronics technology, but also causessevere harm in an electric power system. In thispaper an improved three-level direct torquealgorithm for brushless doubly-fed machines hasbeen developed for reducing the torque and fluxripples in a brushless doubly-fed machine. This...
Electromagnetic Flux Analysis of Permanent Magnet Brushless DC Motor Using Magnet Software
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G.R.Puttalakshmi
2013-08-01
Full Text Available Permanent Magnet Brushless DC (PMBLDC motors is emerging as a suitable motor for a number of drive applications in industrial and consumer products. Cogging torque is one of the important drawbacks of PMBLDC motor which results in shaft vibrations and noise. The focus of this work is to minimize the electromagnetic flux and cogging torque in PMBLDC by introducing structural design modifications. The performance of the machine is analyzed by varying the magnet pole shape, magnet pole width and by using magnetic material with different remenance value. For analyzing the performance of the machine, machine is modeled using Finite Element Analysis (FEA based software package Magnet. Cogging torque and average torque are taken as performance measures to determineoptimum pole shape and pole width.
Optimization of brushless direct current motor design using an intelligent technique.
Shabanian, Alireza; Tousiwas, Armin Amini Poustchi; Pourmandi, Massoud; Khormali, Aminollah; Ataei, Abdolhay
2015-07-01
This paper presents a method for the optimal design of a slotless permanent magnet brushless DC (BLDC) motor with surface mounted magnets using an improved bee algorithm (IBA). The characteristics of the motor are expressed as functions of motor geometries. The objective function is a combination of losses, volume and cost to be minimized simultaneously. This method is based on the capability of swarm-based algorithms in finding the optimal solution. One sample case is used to illustrate the performance of the design approach and optimization technique. The IBA has a better performance and speed of convergence compared with bee algorithm (BA). Simulation results show that the proposed method has a very high/efficient performance. PMID:25841938
Pre-Optimization of Brushless PM Motor Design using Interval Arithmetic
Directory of Open Access Journals (Sweden)
GautamMoni Patro*, Venkata R Basam ,S. Sashidhar , , P. Mallikarjuna Rao
Full Text Available These days, the desperate need for energy, provoked the requirement of energy efficient and ergonomic electrical machines suitable for propulsion, wind power applications, etc. This forces a machine designer to their extreme limits in designing their customized machine suitable for their application. Thus, in this quest for energy efficient electrical machines, there came into existence many new design based theories. In this research work the authors sincerely attempt to identifyand segregate the Brushless PM motor design parametersfrom CAD point of view and apply the concept of Interval Arithmetic; so that a valid range(bounds of the design parameter(s can be determined and acknowledged before going into a suitable optimization technique for optimizing them. With the help of MATLAB®CLI the bounds for the motor design parameters can be determined in which the optimal design solution lies.
Study of direct back EMF detection for sensorless brushless DC motor
Institute of Scientific and Technical Information of China (English)
ZOU Ji-bin; JIANG Shan-lin; LIANG Wei-yan
2010-01-01
In this paper,a new rotor position detecting method for the sensorless control of brushless DC motor(BLDCM)is introduced.It obtains the phase back EMF signal from the motor terminal voltage by properly choosing the PWM and sensing strategy directly and needn' t the motor neutral point voltage information.The paper analyzes both the steady-state of PWM on the high side modulator mode which doesnt consider the parasitic capacitance Coes in the switches and the transient-state of PWM on the high side modulator mode which considers the parasitic capacitance Coes in the switches in detail.The experimental results verify that the proposed method is not sensitive to switching noise,no filtering is required,and good motor performance is achieved within a wide speed range.
Position and Speed Control of Brushless DC Motors Using Sensorless Techniques and Application Trends
Directory of Open Access Journals (Sweden)
Jaime Gómez-Gil
2010-07-01
Full Text Available This paper provides a technical review of position and speed sensorless methods for controlling Brushless Direct Current (BLDC motor drives, including the background analysis using sensors, limitations and advances. The performance and reliability of BLDC motor drivers have been improved because the conventional control and sensing techniques have been improved through sensorless technology. Then, in this paper sensorless advances are reviewed and recent developments in this area are introduced with their inherent advantages and drawbacks, including the analysis of practical implementation issues and applications. The study includes a deep overview of state-of-the-art back-EMF sensing methods, which includes Terminal Voltage Sensing, Third Harmonic Voltage Integration, Terminal Current Sensing, Back-EMF Integration and PWM strategies. Also, the most relevant techniques based on estimation and models are briefly analysed, such as Sliding-mode Observer, Extended Kalman Filter, Model Reference Adaptive System, Adaptive observers (Full-order and Pseudoreduced-order and Artificial Neural Networks.
Development of Limited Angle Brushless Torque Motor Control Drive for Scan Mirror Mechanism
Directory of Open Access Journals (Sweden)
A. Jagadeeshwaran
2013-10-01
Full Text Available This paper illustrate the design and realization of control drive electronics of Limited Angle brushless torque motor for position control of Scan mirror mechanism. The scan mirror mechanism is controlled for the intended limited mechanical angle within +/- 20deg. The control drive is designed for six selectable positions within +/- 20deg with an accuracy of 0.75 degree. These six selectablepositions are achieved with rates of 1 deg/sec, 2 deg/sec and 3 deg/sec according to the requirement. The control input to the drive electronics is given through PC interface for the required position and rate. The input/output is presented in GUI front end. The instantaneous data of present position and rate of the scan mechanism is logged in PC for reference.
Institute of Scientific and Technical Information of China (English)
FU Huinan; CHEN Dongsheng; ZHAO Yong; LIN Binquan
2008-01-01
A minitype precise spindle system which can machine precisely and stably in the process of diamond lapping and polishing is designed. In such minitype spindle system, the brushless DC spindle motor is used to drive the lapping finish table, which is built with fluid dynamic bearings. Some measures have been taken to make the lapping system dynamic balance, and a servo controller which can adjust the speed of motor from 1 200 r/min to 5 400 r/min is designed. Experiments show that the spindle system is reliable and stable for diamond polishing, and the detection results by atomic force microscope(AFM) show that the surfaces of diamond edge's Ra is 6.725 nm and whole diamond average Ra is 3.25 nm.
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Diao Xiaoyan
2016-01-01
Full Text Available To solve the deficiencies of long optimization time and poor precision existing in conventional bacterial foraging algorithm (BFA in the process of parameter optimization, an improved bacterial foraging algorithm (IBFA is proposed and applied to speed and displacement control system of bearingless brushless DC (Bearingless BLDC motors. To begin with the fundamental principle of BFA, the proposed method is introduced and the individual intelligence is efficiently used in the process of parameter optimization, and then the working principle of bearingless BLDC motors is expounded. Finally, modeling and simulation of the speed and displacement control system of bearingless BLDC motors based on the IBFA are carried out by taking the software of MATLAB/Simulink as a platform. Simulation results show that, speed overshoot, torque ripple and rotor position oscillation are dramatically reduced, thus the proposed method has good application prospects in the field of bearingless motors.
Bat algorithm optimized fuzzy PD based speed controller for brushless direct current motor
Directory of Open Access Journals (Sweden)
K. Premkumar
2016-06-01
Full Text Available In this paper, design of fuzzy proportional derivative controller and fuzzy proportional derivative integral controller for speed control of brushless direct current drive has been presented. Optimization of the above controllers design is carried out using nature inspired optimization algorithms such as particle swarm, cuckoo search, and bat algorithms. Time domain specifications such as overshoot, undershoot, settling time, recovery time, and steady state error and performance indices such as root mean squared error, integral of absolute error, integral of time multiplied absolute error and integral of squared error are measured and compared for the above controllers under different operating conditions such as varying set speed and load disturbance conditions. The precise investigation through simulation is performed using simulink toolbox. From the simulation test results, it is evident that bat optimized fuzzy proportional derivative controller has superior performance than the other controllers considered. Experimental test results have also been taken and analyzed for the optimal controller identified through simulation.
International Nuclear Information System (INIS)
EDA technique is used for circuit simulation. The circuit simulation and the analysis are made for a gate circuit one-shot multivibrator. The result shows: EDA circuit simulation is very useful technique
Integrated solar pump design incorporating a brushless DC motor for use in a solar heating system
Energy Technology Data Exchange (ETDEWEB)
Swan, Lukas G.; Allen, Peter L. [Department of Mechanical Engineering, Dalhousie University, 1360 Barrington Street, Halifax, Nova Scotia B3J 1Z1 (Canada)
2010-09-15
Most solar thermal hot water heating systems utilize a pump for circulation of the working fluid. An elegant approach to powering the pump is via solar energy. A ''solar pump'' employs a photovoltaic module, electric motor, and pump to collect and convert solar energy to circulate the working fluid. This article presents an experimental investigation of a new integrated solar pump design that employs the stator of a brushless DC motor and a magnetically coupled pump that has no dynamic seal. This design significantly reduces total volume and mass, and eliminates redundant components. The integrated design meets a hydraulic load of 1.7 bar and 1.4 litres per minute, equal to 4.0 watts, at a rotational speed of 500 revolutions per minute. The brushless DC motor and positive displacement pump achieve efficiencies of 62% and 52%, respectively, resulting in an electric to hydraulic efficiency of 32%. Thus, a readily available photovoltaic module rated 15 watts output is suitable to power the system. A variety of design variations were tested to determine the impact of the armature winding, pump size, pulse width modulation frequency, seal can material, etcetera. The physical and magnetic design was found to dominate efficiency. The efficiency characteristics of a photovoltaic module are such that over-sizing is wasteful. The integrated design presents a robust, efficient package for use as a solar pump. Although focus has been placed on application to a solar thermal collector system, variations of the design are suitable for a wide variety of applications such as remote location water pumping. (author)
Effect of phase advance on the brushless dc motor torque speed respond
Mohd, M. S.; Karsiti, M. N.; Mohd, M. S.
2015-12-01
Brushless direct current (BLDC) motor is widely used in small and medium sized electric vehicles as it exhibit highest specific power and thermal efficiency as compared to the induction motor. Permanent magnets BLDC rotor create a constant magnetic flux, which limit the motor top speed. As the back electromotive force (EMF) voltage increases proportionally with motor rotational speed and it approaches the amplitude of the input voltage, the phase current amplitude will reach zero. By advancing the phase current, it is possible to extend the maximum speed of the BLDC motor beyond the rated top speed. This will allow smaller BLDC motor to be used in small electric vehicles (EV) and in larger applications will allow the use of BLDC motor without the use of multispeed transmission unit for high speed operation. However, increasing the speed of BLDC will affect the torque speed response. The torque output will decrease as speed increases. Adjusting the phase angle will affect the speed of the motor as each coil is energized earlier than the corresponding rise in the back emf of the coil. This paper discusses the phase advance strategy of Brushless DC motor by phase angle manipulation approaches using external hall sensors. Tests have been performed at different phase advance angles in advance and retard positions for different voltage levels applied. The objective is to create the external hall sensor system to commutate the BLDC motor, to establish the phase advance of the BLDC by varying the phase angle through external hall sensor manipulation, observe the respond of the motor while applying the phase advance by hall sensor adjustment.
Walkhoff, Lutz-Ruediger
1989-12-01
With the utilization of high value magnets with stiff magnetization, it is possible to establish a 3-D, analytic field calculation process in which the influence of the permeability is taken into account. The process is based on the reflection laws for the scalar magnetic potential and allows examination of the influence of the permeability on the profile of the induction in gap. The inductivity of the windings is approximately obtained with the magnetic field of the stator windings, that is found three dimensionally in the winding area. Since the permanent magnet material used is a good electrical conductor, eddy current losses can appear in the magnet with phase currents. For the first losses estimation, the stationary stator field in the magnet area was calculated. The induction in the rotor is relatively low for maximal currents so that only very minimal losses occur. The dissipation was calculated with the Paynting vector from the vector potential.
Chen, Wai-Kai
2009-01-01
Featuring hundreds of illustrations and references, this book provides the information on analog and VLSI circuits. It focuses on analog integrated circuits, presenting the knowledge on monolithic device models, analog circuit cells, high performance analog circuits, RF communication circuits, and PLL circuits.
Directory of Open Access Journals (Sweden)
Roni Permana Saputra
2012-03-01
Full Text Available This paper discusses the design of control system for brushless DC motor using microcontroller ATMega 16 that will be applied to an independent 4-wheel drive Mobile Robot LIPI version 2 (REV-11. The control system consists of two parts which are brushless DC motor control module and supervisory control module that coordinates the desired command to the motor control module. To control the REV-11 platform, supervisory control transmit the reference data of speed and direction of motor to control the speed and direction of each actuator on the platform REV-11. From the test results it is concluded that the designed control system work properly to coordinate and control the speed and direction of motion of the actuator motor REV-11 platform.
Gair, S.; Eastham, J. F.; Canova, A.
1996-04-01
The article reports on a study of the effects of slot closure in axial-field permanent magnet brushless machines by a two-dimensional finite element method (2D FEM) of analysis. The closure of the slots is made by using soft magnetic powder wedge material. Parameter values and machine performance for the open and closed slot configuration are computed. In order to test the 2D FEM model, calculated results are compared with measurements and favorable agreement is shown.
Short- circuit tests of circuit breakers
Chorovský, P.
2015-01-01
This paper deals with short-circuit tests of low voltage electrical devices. In the first part of this paper, there are described basic types of short- circuit tests and their principles. Direct and indirect (synthetic) tests with more details are described in the second part. Each test and principles are explained separately. Oscilogram is obtained from short-circuit tests of circuit breakers at laboratory. The aim of this research work is to propose a test circuit for performing indirect test.
A Study of Direct Identification Method of Brushless DC Motor Parameters%无刷直流电动机参数直接辨识法研究
Institute of Scientific and Technical Information of China (English)
袁国珍; 齐蓉; 白文伟
2013-01-01
Against the brushless DC motor already in mass production, a new and practical parameter identification method called direct identification method was proposed. Based on the basic characteristics of the motor's equivalent circuit , the motor's parameter identification strategy was studied, which provided control parameters for precise control of motor. In order to verify the effectiveness of this method, a parameter identification simulation of a finished motor was used. The result indicates that this identification method is simple to implement, has a low computation, has recognition accuracy that can meet the engineering requirements, and is easier to be implemented than traditional identification methods.%针对已经量产、产品化的无刷直流电动机,研究了一种新的实用的无刷直流电动机参数辨识方法——直接辨识法.基于电机等效电路的基本特性,研究电机参数辨识策略,为精确控制电机提供控制参数.为验证该辨识方法的有效性,对一个成品电机进行参数辨识仿真,结果表明该辨识方法的优点是实现简单、运算量小、辨识精度可以满足工程要求,并且较传统辨识方法更易实现.
电动汽车用无刷直流电机控制器设计%Controller Design for DC Brushless Motor of Electric Vehicle
Institute of Scientific and Technical Information of China (English)
舒雄; 杜荣华; 柴健; 舒刚华; 李亚中
2015-01-01
针对四轮独立驱动电动汽车所用电机须调速性好、可靠性高的特点，从工程应用出发，设计一种以dsPIC及MC33035为核心的无刷直流电机控制器。阐述了控制方案及工作原理，给出了硬件电路组成和调速方法。把该控制器运用到自行研制的四轮独立驱动电动汽车上进行测试，其结果表明，该控制器不仅具有响应速度快、调速性能好和稳定性高的特点，且开发成本低，具有广泛的应用价值。%Based on dsPIC and MC33035, a kind of controller is designed for brushless dc motor with good speed regulating and high reliability, which is used in electric car with four-wheel independent drive. The control plan and operating principle are outlined, and the corresponding hardware circuit structure and speed regulation method are introduced. The controller was applied to test self-de-veloped electric car with four-wheel independent drive. The results indicate that the controller have characteristics of fast response, good speed control performance and high stability with low cost and extensive application.
Lim, Edward C
1974-01-01
Excited States, Volume I reviews radiationless transitions, phosphorescence microwave double resonance through optical spectra in molecular solids, dipole moments in excited states, luminescence of polar molecules, and the problem of interstate interaction in aromatic carbonyl compounds. The book discusses the molecular electronic radiationless transitions; the double resonance techniques and the relaxation mechanisms involving the lowest triplet state of aromatic compounds; as well as the optical spectra and relaxation in molecular solids. The text also describes dipole moments and polarizab
On the Application of Brushless DC Motor in Power Tools%浅谈无刷直流电机在电动工具中的应用
Institute of Scientific and Technical Information of China (English)
孙超英
2014-01-01
Make a general introduction to brushless DC motor application of power tools manufacturers, compare the technical difference between brushless DC motor and brush DC motor in powers tools from the structures and principles, combining with the significant advantages and disadvantages of brushless DC motor brushless compared with brush DC motor, to give advice of selection of brushless DC motor or brush DC motor in power tools motor from the cost of manufacturing and quality control.%介绍电动工具制造企业应用无刷直流电机的大致情况，从结构和原理上对比电动工具用无刷直流电机与有刷直流电机的技术性差异，结合无刷直流电机相比有刷直流电机的显著优缺点，从企业制造成本、质量控制角度提出了电动工具用电机选用无刷直流或有刷直流的建议方向。
Directory of Open Access Journals (Sweden)
K.M. Vasyliv
2013-04-01
Full Text Available By means of a mathematical experiment, electromagnetic and electromechanical processes in an independent electric power supply system based on an asynchronized generator with a three-phase modulated exciter are investigated. The processes are analyzed to specify the working capacity of the power supply system during its operation to an induction motors site. Regularities of the electromagnetic and electromechanical processes behavior versus load intensity and the switch control system parameters are identified.
Design and Simulation of New Cascade Brushless Doubly-fed Machine%新型级联式无刷双馈电机设计与仿真
Institute of Scientific and Technical Information of China (English)
徐优; 王自强
2015-01-01
The new cascade Brushless Doubly-fed Machine ( BDFM) is mainly used for wind power , when the speed of prime mover changes , without changing the input frequency of the excitation current , this generator can guarantee the frequency of the output current is constant , which realize the variable speed constant frequency (VSCF) power.The working principle of the new cascade BDFM was derived , and two motors were established in Ansoft software , then imported into Simplorer software , cascaded and simulated . Simulation results show that if the new cascade BDFM make sure two coaxial rotorsare connected with the same phase sequence and two motor pole pairs are equal , it can achieve VSCF power without inv erter.%新型级联式无刷双馈发电机可以看作是普通级联式双馈电机的一种特例，主要用于风力发电，当电机转速变化时，不需要改变输入励磁电压的频率就可以保证电机输出的电压频率恒定，方便的实现了变速恒频发电。对新型级联式双馈电机的工作原理进行了简要论述，在Ansoft软件里面建立了电机的模型，并导入到Simplorer软件，把两个电机级联起来进行了仿真。仿真结果表明新型级联式双馈电机只需确保两电机转子同轴同相序连接，且两电机极对数相等，即可实现无需变频器的变速恒频发电。
Analog circuit design designing dynamic circuit response
Feucht, Dennis
2010-01-01
This second volume, Designing Dynamic Circuit Response builds upon the first volume Designing Amplifier Circuits by extending coverage to include reactances and their time- and frequency-related behavioral consequences.
Photomultiplier blanking circuit
Mcclenahan, J. O.
1972-01-01
Circuit for protecting photomultiplier equipment from current surges which occur when exposed to brilliant illumination is discussed. Components of circuit and details of operation are provided. Circuit diagram to show action of blanking pulse on zener diode is included.
Analog circuit design designing waveform processing circuits
Feucht, Dennis
2010-01-01
The fourth volume in the set Designing Waveform-Processing Circuits builds on the previous 3 volumes and presents a variety of analog non-amplifier circuits, including voltage references, current sources, filters, hysteresis switches and oscilloscope trigger and sweep circuitry, function generation, absolute-value circuits, and peak detectors.
Directory of Open Access Journals (Sweden)
SANJEEV SINGH
2010-12-01
Full Text Available Permanent magnet brushless DC motor (PMBLDCM drives are being employed in many variable speed applications due to their high efficiency, silent operation, compact size, high reliability, ease of control, and low maintenance requirements. These drives have power quality problems and poor power factor at input AC mains as they are mostly fed through diode bridge rectifier based voltage source inverters. To overcome such problems a single-phase single-switch power factor correction AC-DC converter topology based on a Cuk converter is proposed to feed voltage source inverters based PMBLDCM. It focuses on the analysis, design and performance evaluation of the proposed PFC converter topology for a 1.5 kW, 1500 rpm, 400 V PMBLDCM drive used for an air-conditioning system. The proposed PFC converter topology is modelled and its performance is simulated in Matlab-Simulink environment and results show an improved power quality and good power factor in wide speed range of the drive.
Directory of Open Access Journals (Sweden)
GHOLAMIAN, A. S.
2009-06-01
Full Text Available In this paper, a magnet shape optimization method for reduction of cogging torque and torque ripple in Permanent Magnet (PM brushless DC motors is presented by using the reduced basis technique coupled by finite element and design of experiments methods. The primary objective of the method is to reduce the enormous number of design variables required to define the magnet shape. The reduced basis technique is a weighted combination of several basis shapes. The aim of the method is to find the best combination using the weights for each shape as the design variables. A multi-level design process is developed to find suitable basis shapes or trial shapes at each level that can be used in the reduced basis technique. Each level is treated as a separated optimization problem until the required objective is achieved. The experimental design of Taguchi method is used to build the approximation model and to perform optimization. This method is demonstrated on the magnet shape optimization of a 6-poles/18-slots PM BLDC motor.
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Pritha Agrawal
2014-02-01
Full Text Available This paper presents a comparative analysis of speed control of brushless DC motor (BLDC drive fed with conventional two-level, three and five level diode clamped multilevel inverter (DC-MLI. The performance of the drive system is successfully evaluated using Fuzzy Logic (FL based speed controller. The control structure of the proposed drive system is described. The speed and torque characteristic of conventional two-level inverter is compared with the three and five-level multilevel inverter (MLI for various operating conditions. The three and five level diode clamped multilevel inverters are simulated using IGBT’s and the mathematical model of BLDC motor has been developed in MATLAB/SIMULINK environment. The simulation results show that the Fuzzy based speed controller eliminate torque ripples and provides fast speed response. The developed Fuzzy Logic model has the ability to learn instantaneously and adapt its own controller parameters based on disturbances with minimum steady state error, overshoot and rise time of the output voltage.
Control System of Sensorless Brushless DC Motor Based on TMS320F240
Directory of Open Access Journals (Sweden)
Li Zeng
2011-11-01
Full Text Available A brushless DC(BLDC motor with the characteristics of high speed and high power density has been more widely used in industrial area. The BLDC motor requires the position and speed sensors for control. However the position sensors are undesirable from standpoints of size, cost, maintenance and reliability. There are some different ways that can solve this problem, depending on the flux distribution. This paper describes a control system of sensorless BLDC motor. The back-EMF is adopted to detect the rotor position. The back-EMF is very small in the motor starting process, and it is difficult to obtain rotor position efficiently. A re-setting method of the rotor is proposed in the paper, and current closed loop is used for high-speed and safety in the motor starting process. A good speed and current double closed loops system is designed. The speed and current regulators are implemented by a digital signal processor(DSP. A simple algorithm is used to calculate motor speed indirectly by the software, which simplifies the system hardware structure. The hardware structure and software design of sensorless BLDC motor control system are described in details. The simulation and experimental results have shown the validity of the sensorless control system and the accuracy of the detective position signal obtained.
Optimal Control for Single-Phase Brushless DC Motor with Hall Sensor
Directory of Open Access Journals (Sweden)
Dawei Meng
2013-02-01
Full Text Available This study deals with the optimization control of a single-phase brushless DC motor (BLDCM with Hall sensor. A simple modeling method with feasible parameter identification is adopted to meet characteristics of single-phase BLDCM. With the linear Hall sensor feedback, the advantages of current-mode control scheme and soft-commutation scheme are proposed to achieve maximum efficiency over the entire speed range. This thesis also develops a low-cost and high efficiency control for single-phase BLDCM. The hardware test platform has been constructed on a single-chip Field Programmable Gate Array (FPGA of Cyclone II Family of Altera to verify the performance and feasibility of the proposed optimization control strategies. When using the control scheme with Hall sensor, experimental results show that there are at least a 10% improvement for average value of dc-link current, a 10% improvement for RMS value of phase current and a 40% improvement for peak value of phase current.
Speed Control Analysis of Brushless DC Motor Based on Maximum Amplitude DC Current Feedback
Directory of Open Access Journals (Sweden)
Hassan M.A.A.
2014-07-01
Full Text Available This paper describes an approach to develop accurate and simple current controlled modulation technique for brushless DC (BLDC motor drive. The approach is applied to control phase current based on generation of quasi-square wave current by using only one current controller for the three phases. Unlike the vector control method which is complicated to be implemented, this simple current modulation technique presents advantages such as phase currents are kept in balance and the current is controlled through only one dc signal which represent maximum amplitude value of trapezoidal current (Imax. This technique is performed with Proportional Integral (PI control algorithm and triangular carrier comparison method to generate Pulse Width Modulation (PWM signal. In addition, the PI speed controller is incorporated with the current controller to perform desirable speed operation of non-overshoot response. The performance and functionality of the BLDC motor driver are verified via simulation by using MATLAB/SIMULINK. The simulation results show the developed control system performs desirable speed operation of non-overshoot and good current waveforms.
Research on an Axial Magnetic-Field-Modulated Brushless Double Rotor Machine
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Bin Yu
2013-09-01
Full Text Available Double rotor machine, an electronic continuously variable transmission, has great potential in application of hybrid electric vehicles (HEVs, wind power and marine propulsion. In this paper, an axial magnetic-field-modulated brushless double rotor machine (MFM-BDRM, which can realize the speed decoupling between the shaft of the modulating ring rotor and that of the permanent magnet rotor is proposed. Without brushes and slip rings, the axial MFM-BDRM offers significant advantages such as excellent reliability and high efficiency. Since the number of pole pairs of the stator is not equal to that of the permanent magnet rotor, which differs from the traditional permanent magnet synchronous machine, the operating principle of the MFM-BDRM is deduced. The relations of corresponding speed and toque transmission are analytically discussed. The cogging toque characteristics, especially the order of the cogging torque are mathematically formulated. Matching principle of the number of pole pairs of the stator, that of the permanent magnet rotor and the number of ferromagnetic pole pieces is inferred since it affects MFM-BDRM’s performance greatly, especially in the respect of the cogging torque and electromagnetic torque ripple. The above analyses are assessed with the three-dimensional (3D finite-element method (FEM.
Optimization Design and Performance Analysis of a PM Brushless Rotor Claw Pole Motor with FEM
Directory of Open Access Journals (Sweden)
Zhenyang Zhang
2016-07-01
Full Text Available A new type of permanent magnet (PM brushless claw pole motor (CPM with soft magnetic composite (SMC core is designed and analyzed in this paper. The PMs are mounted on the claw pole surface, and the three-phase stator windings are fed by variable-frequency three-phase AC currents. The advantages of the proposed CPM are that the slip rings on the rotor are cast off and it can achieve the efficiency improvement and higher power density. The effects of the claw-pole structure parameters, the air-gap length, and the PM thinner parameter of the proposed CPM on the output torque are investigated by using three-dimensional time-stepping finite element method (3D TS-FEM. The optimal rotor structure of the proposed CPM is obtained by using the response surface methodology (RSM and the particle swarm optimization (PSO method and the comparison of full-load performances of the proposed CPM with different material cores (SMC and silicon steel is analyzed.
On Stability of Open-Loop Operation without Rotor Information for Brushless DC Motors
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Zhong Wu
2014-01-01
Full Text Available Open-loop operation mode is often used to control the Brushless DC Motors (BLDCMs without rotor position sensors when the back electromotive force (EMF is too weak due to the very low rotor velocity. The rotor position information is not necessary in this mode and the stator windings are supplied with voltages under a certain ratio of the amplitude to the frequency. However, the rotor synchronization will be destroyed once if the commutation instant is inappropriate. In order to improve the reliability of the open-loop operation mode, a dynamic equation is established to represent the synchronization error between the rotor and the stator. Thereafter, the stability of the open-loop control mode is analyzed by using Lyapunov indirect method. Theoretical analysis indicates that the open-loop control mode is asymptotically stable only when the commutation instant of the stator current lags behind the ideal one suitably. Finally, theoretical analysis is verified through the experimental results of a certain BLDCM.
structure and performance analysis of DC brushless motor%直流无刷电动机的结构与性能分析
Institute of Scientific and Technical Information of China (English)
唐小元
2013-01-01
新世纪以来精密伺服装置向朝着高端不断发展，作为动力的直流无刷电动机作为高性能、高功率密度和长寿面的特种电机越来越引起了人们的重视。通过研究总结无刷电机结构与性能的各种联系与区别，有助于无刷电机的设计和使用。%In the new century, the precision power device has great development,the brushless DC motor as a special-ty motors of high performance and high power density and longevity have attracted people's attention. By studying relations and differences of the structure and properties of brushless motor .It is helpful for brushless motor design and use.
Energy Harvesting Using an Analog Circuit under Multimodal Vibration
Directory of Open Access Journals (Sweden)
Shigeru Shimose
2013-01-01
Full Text Available The efficiency of harvesting energy from a vibrating structure using a piezoelectric transducer and a simple analog circuit is investigated experimentally. This analog circuit was originally invented for a synchronized switch damping on inductor (SSDI technique, which enhances the damping of mechanical vibration. In this study, the circuit is used to implement a synchronized switch harvesting on inductor (SSHI technique. A multiple degree of freedom (MDOF structure is excited by single sinusoidal forces at its resonant frequencies and by random forces. The piezoelectric transducer converts this mechanical energy into electrical energy which is harvested using a standard rectifier bridge circuit with and without our analog circuit. Experimental results show that our analog circuit makes it possible to harvest twice as much energy under both single sinusoidal and random vibration excitations.
Energy Technology Data Exchange (ETDEWEB)
Luo, Shaohua, E-mail: hua66com@163.com [The Jiangsu Key Laboratory of Advanced Manufacturing Technology, Huaiyin Institute of Technology, Huai’an 223003 (China); School of Automation, Chongqing University, Chongqing 400044 (China); Hou, Zhiwei; Chen, Zhong [The Jiangsu Key Laboratory of Advanced Manufacturing Technology, Huaiyin Institute of Technology, Huai’an 223003 (China)
2015-12-15
In this paper, chaos control is proposed for the output- constrained system with uncertain control gain and time delay and is applied to the brushless DC motor. Using the dynamic surface technology, the controller overcomes the repetitive differentiation of backstepping and boundedness hypothesis of pre-determined control gain by incorporating radial basis function neural network and adaptive technology. The tangent barrier Lyapunov function is employed for time-delay chaotic system to prevent constraint violation. It is proved that the proposed control approach can guarantee asymptotically stable in the sense of uniformly ultimate boundedness without constraint violation. Finally, the effectiveness of the proposed approach is demonstrated on the brushless DC motor example.
International Nuclear Information System (INIS)
In this paper, chaos control is proposed for the output- constrained system with uncertain control gain and time delay and is applied to the brushless DC motor. Using the dynamic surface technology, the controller overcomes the repetitive differentiation of backstepping and boundedness hypothesis of pre-determined control gain by incorporating radial basis function neural network and adaptive technology. The tangent barrier Lyapunov function is employed for time-delay chaotic system to prevent constraint violation. It is proved that the proposed control approach can guarantee asymptotically stable in the sense of uniformly ultimate boundedness without constraint violation. Finally, the effectiveness of the proposed approach is demonstrated on the brushless DC motor example
简介永磁无刷直流电机的原理及特点%Brief in Principle and Feature of Permanent Magnetic Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
刘志刚
2014-01-01
介绍无刷直流电机在电动工具中的运用概况，对无刷电机相比有刷电机的特点、结构和控制原理进行分析，展望对电动工具应用新型电机的未来趋势。%Introduce the brushless DC motor used in power tools, analyze the characteristics, structures and control principles of brushless motor compared with brush motor, looking forward to the future trend of the new motor for power tools applications.
Energy Harvesting Using an Analog Circuit under Multimodal Vibration
Shigeru Shimose; Kanjuro Makihara; Junjiro Onoda
2013-01-01
The efficiency of harvesting energy from a vibrating structure using a piezoelectric transducer and a simple analog circuit is investigated experimentally. This analog circuit was originally invented for a synchronized switch damping on inductor (SSDI) technique, which enhances the damping of mechanical vibration. In this study, the circuit is used to implement a synchronized switch harvesting on inductor (SSHI) technique. A multiple degree of freedom (MDOF) structure is excited by single sin...
Directory of Open Access Journals (Sweden)
Takeuchi, Asia
2011-02-01
Full Text Available Excited (or agitated delirium is characterized by agitation, aggression, acute distress and sudden death, often in the pre-hospital care setting. It is typically associated with the use of drugs that alter dopamine processing, hyperthermia, and, most notably, sometimes with death of the affected person in the custody of law enforcement. Subjects typically die from cardiopulmonary arrest, although the cause is debated. Unfortunately an adequate treatment plan has yet to be established, in part due to the fact that most patients die before hospital arrival. While there is still much to be discovered about the pathophysiology and treatment, it is hoped that this extensive review will provide both police and medical personnel with the information necessary to recognize and respond appropriately to excited delirium. [West J Emerg Med. 2011;12(1:77-83.
Energy Technology Data Exchange (ETDEWEB)
Mukhopadhyay, N.C.
1986-01-01
The status of the theory of the low-energy approach to hadron structure is reviewed briefly by surveying a few relevant models. A few examples of tests needed to sort out the predictions of different models pertaining to the quark-gluon structure of hadrons are discussed, and given the resulting physics objectives, a few experimental options for excited baryon research at CFBAF are suggested. (LEW)
Institute of Scientific and Technical Information of China (English)
2011-01-01
The Brushless Direct Current （BLDC） motor is widely used in aerospace area, CNC machines and servo systems that require the high control accuracy Once the faults occur in the motor, it will cause great damage to the whole system. Mechanical faults are common in electric machines, and account for up to 50%-60% of the faults. Approximately, 80% of the mechanical faults lead to the eccentricity. So it is necessary to monitor the health condition of the motor to ensure the faults can be detected earlier and measures will be taken to imorove the reliability.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
This paper develops a unified methodology for a real-time speed control of brushless direct-current motor drive systems in the presence of measurement noise and load torque disturbance. First, the mathematical model and hardware structure of system is established. Next, an optimal state feed back controller using the Kalman filter state estimation technique is derived.This is followed by an adaptive control algorithm to compensate for the effects of noise and disturbance. Those two algorithms working together can provide a very-high-speed regulation and dynamic response over a wide range of operating conditions.Simulated responses are presented to highlight the effectiveness of the proposed control strategy.
Sharkh, S.M.; Lai, S. H.
2010-01-01
This paper discusses the analysis and design of a very thin slotless PM brushless motor whose stator laminations are manufactured from a single strip of steel that is edge wound into a spiral (like a “Slinky”) and then fitted over the windings that are preformed on the outside surface of a non-conducting former. Analytical and finite element analysis (FEA) are used to determine the constrained optimum dimensions of a motor used to drive a rim driven thruster in which the motor rotor is fitted...
Pridham, G J
2013-01-01
Solid-State Circuits provides an introduction to the theory and practice underlying solid-state circuits, laying particular emphasis on field effect transistors and integrated circuits. Topics range from construction and characteristics of semiconductor devices to rectification and power supplies, low-frequency amplifiers, sine- and square-wave oscillators, and high-frequency effects and circuits. Black-box equivalent circuits of bipolar transistors, physical equivalent circuits of bipolar transistors, and equivalent circuits of field effect transistors are also covered. This volume is divided
Santiago, John
2013-01-01
Circuits overloaded from electric circuit analysis? Many universities require that students pursuing a degree in electrical or computer engineering take an Electric Circuit Analysis course to determine who will ""make the cut"" and continue in the degree program. Circuit Analysis For Dummies will help these students to better understand electric circuit analysis by presenting the information in an effective and straightforward manner. Circuit Analysis For Dummies gives you clear-cut information about the topics covered in an electric circuit analysis courses to help
Hysteresis in a quantized superfluid 'atomtronic' circuit.
Eckel, Stephen; Lee, Jeffrey G; Jendrzejewski, Fred; Murray, Noel; Clark, Charles W; Lobb, Christopher J; Phillips, William D; Edwards, Mark; Campbell, Gretchen K
2014-02-13
Atomtronics is an emerging interdisciplinary field that seeks to develop new functional methods by creating devices and circuits where ultracold atoms, often superfluids, have a role analogous to that of electrons in electronics. Hysteresis is widely used in electronic circuits-it is routinely observed in superconducting circuits and is essential in radio-frequency superconducting quantum interference devices. Furthermore, it is as fundamental to superfluidity (and superconductivity) as quantized persistent currents, critical velocity and Josephson effects. Nevertheless, despite multiple theoretical predictions, hysteresis has not been previously observed in any superfluid, atomic-gas Bose-Einstein condensate. Here we directly detect hysteresis between quantized circulation states in an atomtronic circuit formed from a ring of superfluid Bose-Einstein condensate obstructed by a rotating weak link (a region of low atomic density). This contrasts with previous experiments on superfluid liquid helium where hysteresis was observed directly in systems in which the quantization of flow could not be observed, and indirectly in systems that showed quantized flow. Our techniques allow us to tune the size of the hysteresis loop and to consider the fundamental excitations that accompany hysteresis. The results suggest that the relevant excitations involved in hysteresis are vortices, and indicate that dissipation has an important role in the dynamics. Controlled hysteresis in atomtronic circuits may prove to be a crucial feature for the development of practical devices, just as it has in electronic circuits such as memories, digital noise filters (for example Schmitt triggers) and magnetometers (for example superconducting quantum interference devices).
Institute of Scientific and Technical Information of China (English)
马洪雨; 帕孜来·马合木提; 李倩
2016-01-01
According to the controlling strategy of BLDCM, a brushless DC motorof electric motorcycle control system based on PIC16F737 microcontroller was designed, a detail ofhardware circuit andsoftware design methods were given, This system can realize regulation speed, speed limit and stationary speed and has perfect function of protection and assistance. Static and dynamic test of the control system were completed. Experiments show that the control system has a good performance , meet the requirements, the devise have definite practical value.%根据无刷直流电机的工作原理,设计了以PICl6F737单片机为核心的电动摩托车无刷直流电动机控制系统,给出了控制系统的硬件组成和软件设计方法,可以实现调速、限速、定速功能,保护及辅助功能完善.通过对控制系统的静态和动态调试表明系统性能良好,满足设计要求,具有广泛的现实意义.
Institute of Scientific and Technical Information of China (English)
张寿春
2012-01-01
In order to protect the electric actuator driven by the brushless DC motor and controller for locked rotor,avoid the controller is damaged.The method of protection of taking LPC2132 central processing unit and hardware circuit of electric current collected of the control system,at same time intelligent judgment and treatment by using the method of software.Realization of intelligent control in the state of locked rotor,protect the controller.The experiment shows that： the system has reliability and the advantages of processing locked rotor in intelligent mode.%为了防止直流无刷电机驱动的执行器因电机堵转而损坏控制器,控制系统采用以LPC2132微处理器和电流采集等电路相结合的硬件保护方法,同时采用软件进行智能判断与处理。实现了电动执行器在堵转的状态下的智能控制,保护了控制器。实验结果表明：该系统具有可靠性高及智能处理堵转等优点。
Metamodels for New Designs of Outer-Rotor Brushless Synchronous Electric Motors
Dirba, J.; Lavrinovicha, L.
2014-04-01
The authors consider the possibilities to synthesise metamodels for the analysis and optimisation of brushless synchronous motors. The metamodels are presented for new designs of the outer-rotor permanent magnet synchronous motor and the outer-rotor reluctance motor. The metamodels are synthesised based on the results obtained by the numerical calculations of magnetic field taking into account magnetic saturation. Analysis of the results for the motor magnetic field and tests of the metamodels at the selected and intermediate points shows that these can be synthesised with acceptable accuracy using numerical calculations instead of expensive real experiments. Rakstā ir apskatītas metamodeļu iegūšanas iespējas to izmantošanai bezkontaktu sinhrono dzinēju analīzē un optimizācijā. Ir iegūti metamodeļi sinhronam dzinējam ar pastāvīgajiem magnētiem un reaktīvam dzinējam ar ārējo rotoru. Sintezēto metamodeļu iegūšanai izmantoti elektrisko dzinēju magnētiskā lauka skaitlisko aprēķinu rezultāti, ievērojot magnētiskās ķēdes piesātinājumu. Metamodeļu pārbaude aprēķinu un starppunktos parādīja, ka to iegūšanai dārgo reālo eksperimentu vietā var izmantot magnētiskā lauka aprēķinu rezultātus.
Summary of Detecting Rotor Position Technique for Brushless DC Motor%无刷直流电机转子位置检测技术综述
Institute of Scientific and Technical Information of China (English)
吴红星; 叶宇骄; 倪天; 郭庆波
2011-01-01
无刷直流电机是一种先进的机电一体化装置,无刷直流电动机及控制技术由于其本身特点,使其成为驱动控制领域的研究焦点.该文根据无刷直流电机无位置传感器控制特点,分析了无刷直流电机工作原理,结合国内外基于无刷直流电机转子位置检查控制的相关文献,综述了无刷直流电机转子位置检测控制方法发展概况,并针对每种控制方法阐述了其优缺点.%The brushless DC Motor Drives is an advanced mechanical electronic devices. The technology of sensorless brushless DC motor control is becoming researching focus because of its special structure and low cost. The article presented analysis of characteristics and working principle of the brushless DC motor. It also discussed the development of detecting rotor position means for brushless DC motor based on the relevant literature home and abroad. At the same time it described the advantages and disadvantages of various methods according to each new detecting rotor position technique.
Electronic devices and circuits
Pridham, Gordon John
1972-01-01
Electronic Devices and Circuits, Volume 3 provides a comprehensive account on electronic devices and circuits and includes introductory network theory and physics. The physics of semiconductor devices is described, along with field effect transistors, small-signal equivalent circuits of bipolar transistors, and integrated circuits. Linear and non-linear circuits as well as logic circuits are also considered. This volume is comprised of 12 chapters and begins with an analysis of the use of Laplace transforms for analysis of filter networks, followed by a discussion on the physical properties of
The circuit designer's companion
Williams, Tim
2013-01-01
The Circuit Designer's Companion covers the theoretical aspects and practices in analogue and digital circuit design. Electronic circuit design involves designing a circuit that will fulfill its specified function and designing the same circuit so that every production model of it will fulfill its specified function, and no other undesired and unspecified function.This book is composed of nine chapters and starts with a review of the concept of grounding, wiring, and printed circuits. The subsequent chapters deal with the passive and active components of circuitry design. These topics are foll
Intuitive analog circuit design
Thompson, Marc
2013-01-01
Intuitive Analog Circuit Design outlines ways of thinking about analog circuits and systems that let you develop a feel for what a good, working analog circuit design should be. This book reflects author Marc Thompson's 30 years of experience designing analog and power electronics circuits and teaching graduate-level analog circuit design, and is the ideal reference for anyone who needs a straightforward introduction to the subject. In this book, Dr. Thompson describes intuitive and ""back-of-the-envelope"" techniques for designing and analyzing analog circuits, including transistor amplifi
Study of Fuzzy Adaptive PID Control of Brushless DC Motor%无刷直流电机模糊自适应PID控制的研究
Institute of Scientific and Technical Information of China (English)
潘晓磊; 赵川; 吕海立
2016-01-01
为了提高无刷直流电机控制系统的动、静态性能，将模糊控制结合PID控制算法应用到无刷直流电机速度控制系统中。在分析了无刷直流电机速度控制系统的基础上，利用PSIM与MATLAB／Simulink共同建立了无刷直流电动机模糊自适应PID控制的仿真模型，充分发挥了PSIM和MATLAB／Simulink各自在仿真方面的优势，简化了建立仿真模型的过程。仿真结果表明，采用模糊PID集成控制算法能够使无刷直流电机速度控制系统具有更快的响应速度和更强的抗干扰能力，对无刷直流电机控制系统的设计具有一定的指导意义。%In order to improve the static and dynamic performance of brushless DC motor control system, fuzzy control combined with PID control algorithm is applied to the brushless DC motor speed control system, the integration of fuzzy PID control algorithm. On the analysis of the brushless dc motor speed control system, using the MATLAB/Simulink to establish brushless DC motor speed control system simulation model. Among them, the control system of brushless DC motor drive model and control algorithm were established in PSIM and MATLAB/Simulink environment, give full play to their advantages, the PSIM and MATLAB simplifies the process of establishing simulation model. The simulation results show that the integration of fuzzy PID control algorithm can make the brushless DC motor speed control system has better dynamic and static performance and strong anti-jamming capability, the design of brushless DC motor control system has a certain guiding significance.
无轴承无刷直流电机的直接转矩控制%Direct torque control of bearingless brushless DC motor
Institute of Scientific and Technical Information of China (English)
许洁; 刘贤兴; 李兵伟
2012-01-01
无轴承无刷直流电机结合了无轴承电机和无刷直流电机的优点、具有良好的行特性和广泛的运用前景.研究了无轴承无刷直流电机的控制方法,并将直接转矩控制技术应用于无轴承无刷直流电机的转矩绕组.通过Matlab/Simulink仿真和实验结果表明,转矩绕组的直接转矩控制(DTC)能提高系统的响应速度,减少转矩脉动,提高系统的静动态性能且控制方法简单有效.%Bearingless brushless DC motor, combining advantages of brushless DC motor and bearingless motor, has favorable operating characteristics and wide range of applications. In this paper, the control method of bear ingless brushless DC motor is researched, and the bearingless brushless DC motor's torque winding is controlled by using the method of direct torque control ( DTC ). By Matlab/Simulink simulation and experiment of the con trol system, the results show that the application of DTC to torque winding control of bearingless brushless DC motor is correct and feasible. DTC improves the system's response speed, reduces torque ripple, and optimizes the control effect. The control method is relatively simple.
Ironless asynchronous motors with superconducting auxiliary excitation
International Nuclear Information System (INIS)
Describes induction motors having an outer squirrel-cage or slip-ring rotor driving the shaft, and an inner, free-running rotor with the function of compensating the reactive load of the stator. Investigates theoretically the suggestion that a superconducting inner rotor would also produce very high excitation, and enable the iron circuits to be dispensed with. (R.W.S.)
Electrical Circuits and Water Analogies
Smith, Frederick A.; Wilson, Jerry D.
1974-01-01
Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)
Electronic circuits modeling using artificial neural networks
Directory of Open Access Journals (Sweden)
Andrejević Miona V.
2003-01-01
Full Text Available In this paper artificial neural networks (ANN are applied to modeling of electronic circuits. ANNs are used for application of the black-box modeling concept in the time domain. Modeling process is described, so the topology of the ANN, the testing signal used for excitation, together with the complexity of ANN are considered. The procedure is first exemplified in modeling of resistive circuits. MOS transistor, as a four-terminal device, is modeled. Then nonlinear negative resistive characteristic is modeled in order to be used as a piece-wise linear resistor in Chua's circuit. Examples of modeling nonlinear dynamic circuits are given encompassing a variety of modeling problems. A nonlinear circuit containing quartz oscillator is considered for modeling. Verification of the concept is performed by verifying the ability of the model to generalize i.e. to create acceptable responses to excitations not used during training. Implementation of these models within a behavioral simulator is exemplified. Every model is implemented in realistic surrounding in order to show its interaction, and of course, its usage and purpose.
DEFF Research Database (Denmark)
Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro; Vinay, V
2006-01-01
We consider the computational power of constant width polynomial size cylindrical circuits and nondeterministic branching programs. We show that every function computed by a Pi2 o MOD o AC0 circuit can also be computed by a constant width polynomial size cylindrical nondeterministic branching...... program (or cylindrical circuit) and that every function computed by a constant width polynomial size cylindrical circuit belongs to ACC0....
REA, Editors of
2012-01-01
REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Electric Circuits I includes units, notation, resistive circuits, experimental laws, transient circuits, network theorems, techniques of circuit analysis, sinusoidal analysis, polyph
Louwsma, Simon Minze; Vertregt, Maarten
2010-01-01
A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converte
Louwsma, Simon Minze; Vertregt, Maarten
2011-01-01
A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converte
Treu, Jr., Charles A.
1999-08-31
A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes.
J.A. Bergstra; A. Ponse
2010-01-01
Short-circuit evaluation denotes the semantics of propositional connectives in which the second argument is only evaluated if the first argument does not suffice to determine the value of the expression. In programming, short-circuit evaluation is widely used. A short-circuit logic is a variant of p
Transients in shock-excited homopolar generator with exciting winding as an inductive storage
International Nuclear Information System (INIS)
Calculation ratios necessary for the choice of the basic dimensions and evaluation of efficiency of energy conversion for the homopolar shock-excited generator (HSG) combined with inductive energy storage are presented. As for the design the HSG armature is a ''squirrel cage'' fixed on a non-conductive cylinder. It is shown that at HSG self excitation the maximum current in the short circuit ring is much less than the maximum current at the energy outlet and it essentially depends on the active resistance of the ring. Advisability of increasing active resistance of the short circuit rings in HSG design is shown
Maas, Stephen A
2014-01-01
This book differentiates itself by presenting microwave and RF technology from a circuit design viewpoint, rather than a set of electromagnetic problems. The emphasis is on gaining a practical understanding of often overlooked but vital physical processes.This resource provides microwave circuit engineers with analytical techniques for understanding and designing high-frequency circuits almost entirely from a circuit point of view. Electromagnetic concepts are not avoided, but they are employed only as necessary to support circuit-theoretical ones or to describe phenomena such as radiation and
DEFF Research Database (Denmark)
Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.
2010-01-01
We initiate a systematic study of constant depth Boolean circuits built using exact threshold gates. We consider both unweighted and weighted exact threshold gates and introduce corresponding circuit classes. We next show that this gives a hierarchy of classes that seamlessly interleave with the ......We initiate a systematic study of constant depth Boolean circuits built using exact threshold gates. We consider both unweighted and weighted exact threshold gates and introduce corresponding circuit classes. We next show that this gives a hierarchy of classes that seamlessly interleave...... with the well-studied corresponding hierarchies defined using ordinary threshold gates. A major open problem in Boolean circuit complexity is to provide an explicit super-polynomial lower bound for depth two threshold circuits. We identify the class of depth two exact threshold circuits as a natural subclass...
Ochoa, Agustin
2016-01-01
This book describes a consistent and direct methodology to the analysis and design of analog circuits with particular application to circuits containing feedback. The analysis and design of circuits containing feedback is generally presented by either following a series of examples where each circuit is simplified through the use of insight or experience (someone else’s), or a complete nodal-matrix analysis generating lots of algebra. Neither of these approaches leads to gaining insight into the design process easily. The author develops a systematic approach to circuit analysis, the Driving Point Impedance and Signal Flow Graphs (DPI/SFG) method that does not require a-priori insight to the circuit being considered and results in factored analysis supporting the design function. This approach enables designers to account fully for loading and the bi-directional nature of elements both in the feedback path and in the amplifier itself, properties many times assumed negligible and ignored. Feedback circuits a...
Device, system and method for a sensing electrical circuit
Vranish, John M. (Inventor)
2009-01-01
The invention relates to a driven ground electrical circuit. A driven ground is a current-measuring ground termination to an electrical circuit with the current measured as a vector with amplification. The driven ground module may include an electric potential source V.sub.S driving an electric current through an impedance (load Z) to a driven ground. Voltage from the source V.sub.S excites the minus terminal of an operational amplifier inside the driven ground which, in turn, may react by generating an equal and opposite voltage to drive the net potential to approximately zero (effectively ground). A driven ground may also be a means of passing information via the current passing through one grounded circuit to another electronic circuit as input. It may ground one circuit, amplify the information carried in its current and pass this information on as input to the next circuit.
Institute of Scientific and Technical Information of China (English)
HUANG Ping-lin; HU Qian-sheng; YU Li; HUANG Yun-kai
2006-01-01
Based on the configuration of deep slot concentrated coils,an analytical model is developed for predicting the armature reaction field produced by the 3-phase stator windings of permanent magnet brushless DC motors with concentrated coils by using the image method and the analytical functions of the armature reaction and winding inductances are proposed accounting for the influence of statot slotting.This approach is different from the method of equivalent distributed current sheet and more suitable for electric machines,which have concentrated coils and deeper slots.Under different control mode,the different analytical functions are presented.This will be helpful when further analyzing the performance of the motor.The results agree with the experiment very well.
Directory of Open Access Journals (Sweden)
A. Santhi Mary Antony
2015-06-01
Full Text Available Current fed Quasi Z-Source Inverters (qZSI have the advantages of voltage buck-boost capability, improved reliability, reduced passive component ratings, continuous input current, a common dc rail between source and inverter and unique regeneration capability. This current-fed qZSIs are bidirectional with an additional diode, unlike the voltage-fed ZSI that needs a switch to achieve bidirectional power flow. Since current fed quasi Z Source Inverter has many advantages it can be employed for motor drive applications such as Brushless DC motor (BLDC drive. Therefore this study proposes the use of qZSI for BLDC motor. The simulation results for the same are presented in this study.
Low-cost sensorless control of four-switch, brushless DC motor drive with direct back-EMF detection
Institute of Scientific and Technical Information of China (English)
Abolfazl HALVAEI NIASAR; Abolfazl VAHEDI; Hassan MOGHBELLI
2009-01-01
We propose a position sensorless control scheme for a four-switch, three-phase brushless DC motor drive, based on the zero crossing point detection of phase back-EMF voltages using newly defined error functions (EFs). The commutation instants are 30° after detected zero crossing points of the EFs. Developed EFs have greater magnitude rather than phase or line voltages so that the sensorless control can work at a lower speed range. Moreover, EFs have smooth transitions around zero voltage level that reduces the commutation errors. EFs are derived from the filtered terminal voltages Vao and vbo of two low-pass filters, which are used to eliminate high frequency noises for calculation of the average terminal voltages. The feasibility of the proposed sensorless control is demonstrated by simulation and experimental results.
Institute of Scientific and Technical Information of China (English)
Zu-sheng HO; Chii-maw UANG; Ping-chieh WANG
2014-01-01
Brushless DC motor (BLDCM) sensorless driving technology is becoming increasingly established. However, op-timal phase correction still relies on complex calculations or algorithms. In finding the correct commutation point, the problem of phase lag is introduced. In this paper, we extract DC bus current information for auto-calibrating the phase shift to obtain the correct commutation point and optimize the control of BLDC sensorless driving. As we capture only DC bus current information, the original shunt resistor is used in the BLDCM driver and there is no need to add further current sensor components. Software processing using only simple arithmetic operations successfully accomplishes the phase correction. Experimental results show that the proposed method can operate accurately and stably at low or high speed, with light or heavy load, and is suitable for practical applications. This approach will not increase cost but will achieve the best performance/cost ratio and meet market expectations.
Multi-qubit circuit quantum electrodynamics
Energy Technology Data Exchange (ETDEWEB)
Viehmann, Oliver
2013-09-03
Circuit QED systems are macroscopic, man-made quantum systems in which superconducting artificial atoms, also called Josephson qubits, interact with a quantized electromagnetic field. These systems have been devised to mimic the physics of elementary quantum optical systems with real atoms in a scalable and more flexible framework. This opens up a variety of possible applications of circuit QED systems. For instance, they provide a promising platform for processing quantum information. Recent years have seen rapid experimental progress on these systems, and experiments with multi-component circuit QED architectures are currently starting to come within reach. In this thesis, circuit QED systems with multiple Josephson qubits are studied theoretically. We focus on simple and experimentally realistic extensions of the currently operated circuit QED setups and pursue investigations in two main directions. First, we consider the equilibrium behavior of circuit QED systems containing a large number of mutually noninteracting Josephson charge qubits. The currently accepted standard description of circuit QED predicts the possibility of superradiant phase transitions in such systems. However, a full microscopic treatment shows that a no-go theorem for superradiant phase transitions known from atomic physics applies to circuit QED systems as well. This reveals previously unknown limitations of the applicability of the standard theory of circuit QED to multi-qubit systems. Second, we explore the potential of circuit QED for quantum simulations of interacting quantum many-body systems. We propose and analyze a circuit QED architecture that implements the quantum Ising chain in a time-dependent transverse magnetic field. Our setup can be used to study quench dynamics, the propagation of localized excitations, and other non-equilibrium features in this paradigmatic model in the theory of non-equilibrium thermodynamics and quantumcritical phenomena. The setup is based on a
Multi-qubit circuit quantum electrodynamics
International Nuclear Information System (INIS)
Circuit QED systems are macroscopic, man-made quantum systems in which superconducting artificial atoms, also called Josephson qubits, interact with a quantized electromagnetic field. These systems have been devised to mimic the physics of elementary quantum optical systems with real atoms in a scalable and more flexible framework. This opens up a variety of possible applications of circuit QED systems. For instance, they provide a promising platform for processing quantum information. Recent years have seen rapid experimental progress on these systems, and experiments with multi-component circuit QED architectures are currently starting to come within reach. In this thesis, circuit QED systems with multiple Josephson qubits are studied theoretically. We focus on simple and experimentally realistic extensions of the currently operated circuit QED setups and pursue investigations in two main directions. First, we consider the equilibrium behavior of circuit QED systems containing a large number of mutually noninteracting Josephson charge qubits. The currently accepted standard description of circuit QED predicts the possibility of superradiant phase transitions in such systems. However, a full microscopic treatment shows that a no-go theorem for superradiant phase transitions known from atomic physics applies to circuit QED systems as well. This reveals previously unknown limitations of the applicability of the standard theory of circuit QED to multi-qubit systems. Second, we explore the potential of circuit QED for quantum simulations of interacting quantum many-body systems. We propose and analyze a circuit QED architecture that implements the quantum Ising chain in a time-dependent transverse magnetic field. Our setup can be used to study quench dynamics, the propagation of localized excitations, and other non-equilibrium features in this paradigmatic model in the theory of non-equilibrium thermodynamics and quantumcritical phenomena. The setup is based on a
Nonlinear Dynamics Based Digital Logic and Circuits
Behnam eKia; John Florian Lindner; William eDitto
2015-01-01
We discuss the role and importance of dynamics in the brain and biological neural networks, and argue that dynamics is one of the main missing elements in conventional Boolean logic and circuits. We summarize a simple dynamics based computing method, and categorize different techniques that we have introduced to realize logic, functionality, and programmability. We discuss the role and importance of coupled dynamics in networks of biological excitable cells, and then review our simple coupled...
Hickman, Ian
2013-01-01
Analog Circuits Cookbook presents articles about advanced circuit techniques, components and concepts, useful IC for analog signal processing in the audio range, direct digital synthesis, and ingenious video op-amp. The book also includes articles about amplitude measurements on RF signals, linear optical imager, power supplies and devices, and RF circuits and techniques. Professionals and students of electrical engineering will find the book informative and useful.
Stochastic Switching Circuit Synthesis
Wilhelm, Daniel; Bruck, Jehoshua
2009-01-01
Shannon in his 1938 Masterpsilas Thesis demonstrated that any Boolean function can be realized by a switching relay circuit, leading to the development of deterministic digital logic. Here, we replace each classical switch with a probabilistic switch (pswitch). We present algorithms for synthesizing circuits closed with a desired probability, including an algorithm that generates optimal size circuits for any binary fraction. We also introduce a new duality property for series-parallel stocha...
Regenerative feedback resonant circuit
Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.
2014-09-02
A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.
Dobkin, Bob
2012-01-01
Analog circuit and system design today is more essential than ever before. With the growth of digital systems, wireless communications, complex industrial and automotive systems, designers are being challenged to develop sophisticated analog solutions. This comprehensive source book of circuit design solutions aids engineers with elegant and practical design techniques that focus on common analog challenges. The book's in-depth application examples provide insight into circuit design and application solutions that you can apply in today's demanding designs. <
Louwsma, Simon Minze; Vertregt, Maarten
2011-01-01
A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converter via a respective output switch. The output switch of each channel opens for a tracking time period when the track-and-hold circuit is in a tracking mode for sampling the signal, and closes for a ...
Electronic devices and circuits
Pridham, Gordon John
1968-01-01
Electronic Devices and Circuits, Volume 1 deals with the design and applications of electronic devices and circuits such as passive components, diodes, triodes and transistors, rectification and power supplies, amplifying circuits, electronic instruments, and oscillators. These topics are supported with introductory network theory and physics. This volume is comprised of nine chapters and begins by explaining the operation of resistive, inductive, and capacitive elements in direct and alternating current circuits. The theory for some of the expressions quoted in later chapters is presented. Th
Security electronics circuits manual
MARSTON, R M
1998-01-01
Security Electronics Circuits Manual is an invaluable guide for engineers and technicians in the security industry. It will also prove to be a useful guide for students and experimenters, as well as providing experienced amateurs and DIY enthusiasts with numerous ideas to protect their homes, businesses and properties.As with all Ray Marston's Circuits Manuals, the style is easy-to-read and non-mathematical, with the emphasis firmly on practical applications, circuits and design ideas. The ICs and other devices used in the practical circuits are modestly priced and readily available ty
Marston, R M
1995-01-01
CMOS Circuits Manual is a user's guide for CMOS. The book emphasizes the practical aspects of CMOS and provides circuits, tables, and graphs to further relate the fundamentals with the applications. The text first discusses the basic principles and characteristics of the CMOS devices. The succeeding chapters detail the types of CMOS IC, including simple inverter, gate and logic ICs and circuits, and complex counters and decoders. The last chapter presents a miscellaneous collection of two dozen useful CMOS circuits. The book will be useful to researchers and professionals who employ CMOS circu
Timergenerator circuits manual
Marston, R M
2013-01-01
Timer/Generator Circuits Manual is an 11-chapter text that deals mainly with waveform generator techniques and circuits. Each chapter starts with an explanation of the basic principles of its subject followed by a wide range of practical circuit designs. This work presents a total of over 300 practical circuits, diagrams, and tables.Chapter 1 outlines the basic principles and the different types of generator. Chapters 2 to 9 deal with a specific type of waveform generator, including sine, square, triangular, sawtooth, and special waveform generators pulse. These chapters also include pulse gen
Chen, Wai-Kai
2003-01-01
A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi
Wolfendale, E
2013-01-01
MOS Integral Circuit Design aims to help in the design of integrated circuits, especially large-scale ones, using MOS Technology through teaching of techniques, practical applications, and examples. The book covers topics such as design equation and process parameters; MOS static and dynamic circuits; logic design techniques, system partitioning, and layout techniques. Also featured are computer aids such as logic simulation and mask layout, as well as examples on simple MOS design. The text is recommended for electrical engineers who would like to know how to use MOS for integral circuit desi
Directory of Open Access Journals (Sweden)
Weiran Wang
2013-06-01
Full Text Available In order to improve the performance of bearingless brushless DC motor, a closed-loop suspended force controller combining the discrete space voltage vector modulation is applied and the direct torque control is presented in this paper. Firstly, we increase the number of the control vector to reduce the torque ripple. Then, the suspending equation is constructed which is spired by the direct torque control algorithm. As a result, the closed-loop suspended force controller is built. The simulated and experimental results evaluate the performance of the proposed method. The more advantage is that the proposed algorithm can achieve the fast torque response, reduce the torque ripple, and follow ideal stator flux track. Furthermore, the motor which implants the closed-loop suspended force controller cannot onlyobtain the dynamic response rapidly and displacement control accurately, but also has the characteristics of bearingless brushless DC motor (such as simple structure, high energy efficiency, small volume and low failure rate.
Directory of Open Access Journals (Sweden)
Shaohua Luo
2015-12-01
Full Text Available In this paper, chaos control is proposed for the output- constrained system with uncertain control gain and time delay and is applied to the brushless DC motor. Using the dynamic surface technology, the controller overcomes the repetitive differentiation of backstepping and boundedness hypothesis of pre-determined control gain by incorporating radial basis function neural network and adaptive technology. The tangent barrier Lyapunov function is employed for time-delay chaotic system to prevent constraint violation. It is proved that the proposed control approach can guarantee asymptotically stable in the sense of uniformly ultimate boundedness without constraint violation. Finally, the effectiveness of the proposed approach is demonstrated on the brushless DC motor example.
Institute of Scientific and Technical Information of China (English)
马诗洋; 陈昊
2012-01-01
In order to realize sampling the voltage and current signals accurately and timely, and solve the problems of the versatility of vari ous signal sampling circuit in the control board, DC sampling was applied, and the method of isolating the tested circuit and the control cir cuit which using high-speed linear optocoupler HCNR201 was used. Through the theoretical analysis of the designed circuit, the transfer function between the sampled data of voltage and the sampled data of current Hall sensor was created. After the analysis, the experiment was conducted in the brushless doubly fed wind power generation system experimental platform. The actual transfer function between the sampled data of voltage and the sampled data of current Hall sensor was given. Theoretical fitting curve of the transfer function and the actual fitting curve of the transfer function were compared. The results indicate that the designed detection method has small error and good reliability, and lays a foundation for the next experiment.%为了实现在无刷双馈风力发电系统中,精确、及时地对电压电流信号进行采样,以及解决控制板上各路信号采样电路通用性的问题,采用了直流采样方法.将高速线性光耦HCNR201以被测电路和控制电路电气隔离的方法应用到所设计的采样电路中；通过开展所设计电路的理论分析,建立了电压电流霍尔传感器采集数据与单片机采样数据之间的关系；在理论分析的基础上,在无刷双馈风力发电系统实验平台上进行了试验,得到了电压电流霍尔传感器采集数据与单片机采样数据之间的实际传递函数；最后,对传递函数理论拟合曲线和实际拟合曲线进行了比较.试验结果表明,所设计的无刷双馈风力发电系统电压电流信号检测方法误差小、可靠件强,为下一步研究提供了参考.
Research of Zero-Crossing Detection for Sensorless Brushless DC Based on DSC%基于DSC的无刷直流电动机过零检测方法
Institute of Scientific and Technical Information of China (English)
朱乐乐; 王宜怀; 胡玉鑫; 王浩
2013-01-01
The key technology of sensorless brushless DC motor control is zero-crossing detection. Based on full research and analysis of the hack-EMF motor principle,wave and traditional detection methods,a new method of back-EMF zero-crossing detection was introduced. The method did not rigidly adhere to the principles of traditional back-EMF zero-crossing detection, and the motor midpoint, depth filter and voltage comparison circuits in the design of the traditional zero-crossing detection circuit were rejected. The commutation points were received by realizing three-phase voltage real time collection,filtering and designing the effective software algorithms. The method was applied in the electric car control system. The experiment result shows that the method has some advantages which are simple zero-crossing detection circuits, software with clear structure and good real-time and so on.%无位置传感器无刷直流电动机的过零检测是该类型电机控制的关键技术.在充分研究与分析该类电机的反电动势原理、波形及传统检测方法的基础上,提出了一种反电动势过零检测新方法.该方法不拘泥于传统反电动势过零检测原理,摈弃了传统过零检测电路设计中的电机中点、深度滤波及电压比较等电路,利用DSC实现三相端电压动态实时采集、滤波,并设计有效的软件算法,得到换相点.实际应用结果表明,该过零检测电路具有实现简洁、软件结构清晰及实时性好等优点.
Brushless DC Motor Self-Adaption Fuzzy PID Control System%无刷直流电机自适应模糊PID控制系统
Institute of Scientific and Technical Information of China (English)
王国玲; 李振宇; 范自道
2013-01-01
针对无刷直流电机传统PID控制存在精度低、抗干扰能力差及模糊控制稳态精度不高等问题，研究了一种自适应模糊PID控制方法。论文分析了直流无刷电机的工作原理，建立了直流无刷电机自适应模糊PID控制系统的计算机仿真数学模型，设计了系统速度环的模糊PID控制器，仿真结果表明，与传统PID控制相比，自适应模糊PID控制的BLDCM系统具有更高的稳定性和控制精度、更快的动态响应速度。%For the lower precision,bad anti-interference capability of traditional PID control and lower stable precision of fuzzy control for brushless DC motor,an adaptive fuzzy-PID control was deeply investigated in this paper. Working theory of brushless DC motor was analyzed,the simulated mathematical model of adaptive fuzzy-PID control for brushless DC motor was established,and the fuzzy-PID controller of speed regulator was designed. The results of simulation verified the better stability,the faster dynamic speed of adaptive fuzzy-PID control for brushless DC motor compared to traditional PID control.
Tianxun Chen; Xiaopeng Wu; Yugang Dong; Chengning Zhang; Haipeng Liu
2016-01-01
This paper presents a computationally efficient loss prediction procedure and thermal analysis of surface-mounted brushless AC permanent magnet (PM) machine considering the UDDS driving duty cycle by using a lumped parameters’ thermal model. The accurate prediction of loss and its variation with load are essential for thermal analysis. Employing finite element analysis (FEA) to determine loss at every load point would be computationally intensive. Here, the finite element analysis and/or expe...
SIMPEL: Circuit model for photonic spike processing laser neurons
Bhavin J. Shastri; Nahmias, Mitchell A.; Tait, Alexander N.; Wu, Ben; Prucnal, Paul R.
2014-01-01
We propose an equivalent circuit model for photonic spike processing laser neurons with an embedded saturable absorber---a simulation model for photonic excitable lasers (SIMPEL). We show that by mapping the laser neuron rate equations into a circuit model, SPICE analysis can be used as an efficient and accurate engine for numerical calculations, capable of generalization to a variety of different laser neuron types found in literature. The development of this model parallels the Hodgkin--Hux...
Resonator having a selection circuit for selecting a resonance mode
Verhoeven, C.J.
1998-01-01
Resonator provided with a resonating device and with a selection circuit for selecting a resonance mode. The selection circuit is formed by a first-order oscillator which is provided with a synchronization input and whose output is connected to the excitation input of the resonating device, the output of the resonating device being connected to the synchronization input of the first-order oscillator in order to synchronize said oscillator and the output signal of the resonator being derived f...
无刷直流电机的模糊控制系统仿真%Simulation of Fuzzy Control for Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
焦利利; 杨风
2014-01-01
This paper introduces the brushless DC motor of basic principle and mathematical model. Through the Simulink toolbox of the MATLAB model to build the fuzzy controller, the fuzzy control method of Brushless DC motor speed control., which achieves realization of Brushless DC motor fuzzy control system computer simulation. The results show that, the fuzzy controller has the advantages of simple structure, easy to implement, which can basically meet the system performance requirements.%本文介绍了无刷直流电机基本原理和数学模型。利用Matlab软件中Simulink工具箱搭建模糊控制器，采用模糊控制法对无刷直流电机进行调速。实现了无刷直流电机的模糊控制系统的计算机仿真。结果表明，该模糊控制器结构简单、易于实现，能够基本满足系统的性能要求。
Vick, Matthew E.
2010-01-01
The University of Colorado's Physics Education Technology (PhET) website offers free, high-quality simulations of many physics experiments that can be used in the classroom. The Circuit Construction Kit, for example, allows students to safely and constructively play with circuit components while learning the mathematics behind many circuit…
Synchronizing Hyperchaotic Circuits
DEFF Research Database (Denmark)
Tamasevicius, Arunas; Cenys, Antanas; Namajunas, Audrius;
1997-01-01
Regarding possible applications to secure communications the technique of synchronizing hyperchaotic circuits with a single dynamical variable is discussed. Several specific examples including the fourth-order circuits with two positive Lyapunov exponents as well as the oscillator with a delay line...
Approximate circuits for increased reliability
Energy Technology Data Exchange (ETDEWEB)
Hamlet, Jason R.; Mayo, Jackson R.
2015-12-22
Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.
Approximate circuits for increased reliability
Energy Technology Data Exchange (ETDEWEB)
Hamlet, Jason R.; Mayo, Jackson R.
2015-08-18
Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.
Institute of Scientific and Technical Information of China (English)
张相军; 陈伯时
2001-01-01
This paper introduces four PWM modes used in the sensorless brushless DC motor control system, analyzes their different influences on the commutation torque ripple in detail, and selects the best PWM mode in four given types to reduce commutation torque ripple of Brushless OC(BLDC) motors. Simulation and experimental results show that the selection is correct and practical.
Optoelectronics circuits manual
Marston, R M
2013-01-01
Optoelectronics Circuits Manual covers the basic principles and characteristics of the best known types of optoelectronic devices, as well as the practical applications of many of these optoelectronic devices. The book describes LED display circuits and LED dot- and bar-graph circuits and discusses the applications of seven-segment displays, light-sensitive devices, optocouplers, and a variety of brightness control techniques. The text also tackles infrared light-beam alarms and multichannel remote control systems. The book provides practical user information and circuitry and illustrations.
Circuit analysis with Multisim
Baez-Lopez, David
2011-01-01
This book is concerned with circuit simulation using National Instruments Multisim. It focuses on the use and comprehension of the working techniques for electrical and electronic circuit simulation. The first chapters are devoted to basic circuit analysis.It starts by describing in detail how to perform a DC analysis using only resistors and independent and controlled sources. Then, it introduces capacitors and inductors to make a transient analysis. In the case of transient analysis, it is possible to have an initial condition either in the capacitor voltage or in the inductor current, or bo
Troubleshooting analog circuits
Pease, Robert A
1991-01-01
Troubleshooting Analog Circuits is a guidebook for solving product or process related problems in analog circuits. The book also provides advice in selecting equipment, preventing problems, and general tips. The coverage of the book includes the philosophy of troubleshooting; the modes of failure of various components; and preventive measures. The text also deals with the active components of analog circuits, including diodes and rectifiers, optically coupled devices, solar cells, and batteries. The book will be of great use to both students and practitioners of electronics engineering. Other
DEFF Research Database (Denmark)
2009-01-01
A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...... impedance, an energy-storing element being connected to the second terminal of the load impedance and providing an output signal, and a measuring unit that measures the output signal or compares the output signal with a reference....
Marston, R M
2013-01-01
Modern TTL Circuits Manual provides an introduction to the basic principles of Transistor-Transistor Logic (TTL). This book outlines the major features of the 74 series of integrated circuits (ICs) and introduces the various sub-groups of the TTL family.Organized into seven chapters, this book begins with an overview of the basics of digital ICs. This text then examines the symbology and mathematics of digital logic. Other chapters consider a variety of topics, including waveform generator circuitry, clocked flip-flop and counter circuits, special counter/dividers, registers, data latches, com
Plasmonic Nanoguides and Circuits
Bozhevolnyi, Sergey
2008-01-01
Modern communication systems dealing with huge amounts of data at ever increasing speed try to utilize the best aspects of electronic and optical circuits. Electronic circuits are tiny but their operation speed is limited, whereas optical circuits are extremely fast but their sizes are limited by diffraction. Waveguide components utilizing surface plasmon (SP) modes were found to combine the huge optical bandwidth and compactness of electronics, and plasmonics thereby began to be considered as the next chip-scale technology. In this book, the authors concentrate on the SP waveguide configurati
Pragmatic circuits frequency domain
Eccles, William
2006-01-01
Pragmatic Circuits: Frequency Domain goes through the Laplace transform to get from the time domain to topics that include the s-plane, Bode diagrams, and the sinusoidal steady state. This second of three volumes ends with a-c power, which, although it is just a special case of the sinusoidal steady state, is an important topic with unique techniques and terminology. Pragmatic Circuits: Frequency Domain is focused on the frequency domain. In other words, time will no longer be the independent variable in our analysis. The two other volumes in the Pragmatic Circuits series include titles on DC
Monolithic microwave integrated circuits
Pucel, R. A.
Monolithic microwave integrated circuits (MMICs), a new microwave technology which is expected to exert a profound influence on microwave circuit designs for future military systems as well as for the commercial and consumer markets, is discussed. The book contains an historical discussion followed by a comprehensive review presenting the current status in the field. The general topics of the volume are: design considerations, materials and processing considerations, monolithic circuit applications, and CAD, measurement, and packaging techniques. All phases of MMIC technology are covered, from design to testing.
Counting rate logarithmic circuits
International Nuclear Information System (INIS)
This paper describes the basic circuit and the design method for a multidecade logarithmic counting ratemeter. The method is based on the charging and discharging of several RC time constants. An F.E.T. switch is used and the drain current is converted into a proportional voltage by a current to voltage converter. The logarithmic linearity was estimated for 4 decades starting from 50 cps. This circuit can be used in several nuclear instruments like survey meters and counting systems. This circuits has been developed as part of campbell channel instrumentation. (author)
Circuit for Driving Piezoelectric Transducers
Randall, David P.; Chapsky, Jacob
2009-01-01
The figure schematically depicts an oscillator circuit for driving a piezoelectric transducer to excite vibrations in a mechanical structure. The circuit was designed and built to satisfy application-specific requirements to drive a selected one of 16 such transducers at a regulated amplitude and frequency chosen to optimize the amount of work performed by the transducer and to compensate for both (1) temporal variations of the resonance frequency and damping time of each transducer and (2) initially unknown differences among the resonance frequencies and damping times of different transducers. In other words, the circuit is designed to adjust itself to optimize the performance of whichever transducer is selected at any given time. The basic design concept may be adaptable to other applications that involve the use of piezoelectric transducers in ultrasonic cleaners and other apparatuses in which high-frequency mechanical drives are utilized. This circuit includes three resistor-capacitor networks that, together with the selected piezoelectric transducer, constitute a band-pass filter having a peak response at a frequency of about 2 kHz, which is approximately the resonance frequency of the piezoelectric transducers. Gain for generating oscillations is provided by a power hybrid operational amplifier (U1). A junction field-effect transistor (Q1) in combination with a resistor (R4) is used as a voltage-variable resistor to control the magnitude of the oscillation. The voltage-variable resistor is part of a feedback control loop: Part of the output of the oscillator is rectified and filtered for use as a slow negative feedback to the gate of Q1 to keep the output amplitude constant. The response of this control loop is much slower than 2 kHz and, therefore, does not introduce significant distortion of the oscillator output, which is a fairly clean sine wave. The positive AC feedback needed to sustain oscillations is derived from sampling the current through the
Laurent Guiraud
1999-01-01
A printed circuit board made by scientists in the ATLAS collaboration for the transition radiaton tracker (TRT). This will read data produced when a high energy particle crosses the boundary between two materials with different electrical properties.
Single Element Excitation and Detection of (Micro-)Mechanical Resonators
Tilmans, Harrie A.C.; IJntema, Dominicus J.; Fluitman, Jan H.J
1991-01-01
The authors describe a single-element approach for the excitation and detection of the vibrational motion of (micro-)mechanical resonators. An equivalent electrical one-port network is derived for an electrostatically and a piezoelectrically driven resonator. In this way, the effect of the mechanical resonator is transformed into the electrical domain and can easily be accounted for in a circuit simulation. A detection circuit, based on an (on-chip) bridged design, is proposed as a way to com...
Hockenberry, Adam J.; Jewett, Michael C.
2012-01-01
Inspired by advances in the ability to construct programmable circuits in living organisms, in vitro circuits are emerging as a viable platform for designing, understanding, and exploiting dynamic biochemical circuitry. In vitro systems allow researchers to directly access and manipulate biomolecular parts without the unwieldy complexity and intertwined dependencies that often exist in vivo. Experimental and computational foundations in DNA, DNA/RNA, and DNA/RNA/protein based circuitry have g...
Design of Excitation Capacitance for Self-Excited Induction Generator
Directory of Open Access Journals (Sweden)
Swati Devabhaktuni
2011-12-01
Full Text Available This paper presents simple and accurate approach to compute the minimum value of capacitance required for initiating the voltage build-up in a three-phase selfexcited induction generator. Based on the steady-state equivalent circuit model different numerical methods for solving frequency are known from previous literature, which are of 6th order polynomial. In this paper the order of the polynomial is reduced to the 4thorder frequency with a new, simple and direct method is developed to find the capacitance requirement. Critical values of the impedance and speed, below which the machine fails to self excite irrespective of the capacitance used, are found to exist. Closed form solutions for capacitance are derived for no-load and RL loads. Experimental results obtained on a 3.5kW induction machine confirm the feasibility and accuracy of the proposed method.
Research and application of dual-mode operation technology of brushless DC motor%无刷直流电机双模控制技术研究与应用
Institute of Scientific and Technical Information of China (English)
李凤祥; 朱伟进
2013-01-01
针对无刷直流电机的无位置传感器控制“三段式”起动技术的缺陷,以电动自行车为研究对象,采用反电动势过零点检测方法和相位补偿技术,通过改进反电动势检测电路,优化无位置传感器控制的起动方法,设计出基于相位补偿的双模式运行无刷直流电机控制方案,使无刷直流电机可运行在有位置传感器和无位置传感器两种模式下,当位置传感器信号输出正常时,电机默认运行在有位置传感器模式;若位置传感器信号输出不正常,电机自动切换运行在无位置传感器模式.实验证明,反电势检测电路灵敏度高,且很好的实现了相移补偿,两种模式切换过程平稳,运行状态平稳.%Aiming at overcoming shortcoming of " three-step" start method of the brushless DC motor (BLDCM) sensorless control, a dual-mode BLDCM controller was developed based on phase compensation technology by studying electric bicycle, using back electromotive force(back-EMF)detection method and improving the back-EMF detection circuit and position sensorless starting method. By using the technology , BLDCM can be run on position sensor mode and sensorless mode. When the position sensor signal output is normal, the motor is run on the position sensor mode in default; otherwise, when position sensor signal output is abnormal, the motor automatically switches to be run on the mode without position sensor. The experimental result proves that the detection circuit boasts high sensitivity and completely compensates the phase delay; two modes work steadily and the switching process is smooth.
International Nuclear Information System (INIS)
The peak reading detector circuit serves for picking up the instants during which peaks of a given polarity occur in sequences of signals in which the extreme values, their time intervals, and the curve shape of the signals vary. The signal sequences appear in measuring the foetal heart beat frequence from amplitude-modulated ultrasonic, electrocardiagram, and blood pressure signals. In order to prevent undesired emission of output signals from, e. g., disturbing intermediate extreme values, the circuit consists of the series connections of a circuit to simulate an ideal diode, a strong unit, a discriminator for the direction of charging current, a time-delay circuit, and an electronic switch lying in the decharging circuit of the storage unit. The time-delay circuit thereby causes storing of a preliminary maximum value being used only after a certain time delay for the emission of the output signal. If a larger extreme value occurs during the delay time the preliminary maximum value is cleared and the delay time starts running anew. (DG/PB)
Institute of Scientific and Technical Information of China (English)
骆光照; 张围围; 杨南方; 马鹏; 刘卫国
2012-01-01
A flux linkage compensation field oriented control (FOC) method was proposed to suppress the speed and torque ripples of a hrusbless wound-fleld synchronous motor in its starting process. The starting process was analyzed and the model of wound-field synchronous electric machine was established. The change of field current of the electric machine was described mathematically for simplified exciter and rotate rectifier. Based on the traditional field control, the flux linkage compensation was introduced in d-axis current to counteract the flux ripple. Some simulation and preliminary experiments were implemented. The results show that the proposed method is feasible and effective.
Brushless Starting Magneto for Motor Cycle%摩托车用无刷起动磁电机
Institute of Scientific and Technical Information of China (English)
任立环; 刘迎澍; 李家国
2001-01-01
In view of the problems of difficult maintenance and short usage life ,etc.existed in previous magneto and electric generating started by carbon-brush and commutator device,a brushless starting magneto for motor cycle is introduced in this paper, it integrates the functions of starting, generating and igniting,uses the electronic inverter instead of mechanic inverter to overcome a series of problems caused by the electric brush and the commutator. The structures of magneto and inverter and the features of ignition system are described in this paper in detail.%针对早期的起动磁电机起动及发电均通过碳刷整流子装置，存在维护困难、使用寿命短等问题。介绍了一种摩托车用无刷起动磁电机，它集起动、发电与点火功能于一体，并采用电子换向器替代机械换向装置，从而克服了由电刷和整流子所带来的一系列问题。详细介绍了其电机结构、电子换向器结构及点火系统的特点。
Directory of Open Access Journals (Sweden)
Quanwu Li
2016-01-01
Full Text Available High reliability is required for the permanent magnet brushless DC motor (PM-BLDCM in an electrical pump of hypersonic vehicle. The PM-BLDCM is a short-time duty motor with high-power-density. Since thermal equilibrium is not reached for the PM-BLDCM, the temperature distribution is not uniform and there is a risk of local overheating. The winding is a main heat source and its insulation is thermally sensitive, so reducing the winding temperature rise is the key to the improvement of the reliability. In order to reduce the winding temperature rise, an electromagnetic-thermal integrated design optimization method is proposed. The method is based on electromagnetic analysis and thermal transient analysis. The requirements and constraints of electromagnetic and thermal design are considered in this method. The split ratio and the maximum flux density in stator lamination, which are highly relevant to the windings temperature rise, are optimized analytically. The analytical results are verified by finite element analysis (FEA and experiments. The maximum error between the analytical and the FEA results is 4%. The errors between the analytical and measured windings temperature rise are less than 8%. It can be proved that the method can obtain the optimal design accurately to reduce the winding temperature rise.
Institute of Scientific and Technical Information of China (English)
李节宝; 章跃进
2011-01-01
Torque ripple suppression was the research focus of permanent magnet brushless motor, domestic and foreign experts and scholars had proposed lots of solutions for the problem. First analysis the compositions of permanent magnet brushless motor torque ripple and various reasons which casue the torque ripple, then the commonly use methods of reducing permanent magnet brushless motor pulsating ripple was summarized and introduced.%抑制转矩脉动是永磁无刷电机研究重点,国内外专家学者提出了诸多解决方法.在分析永磁无刷电机脉动转矩的组成及产生原因的基础上,综合介绍了削弱永磁无刷电动机转矩脉动常用的一些方法.
SIMPEL: Circuit model for photonic spike processing laser neurons
Shastri, Bhavin J; Tait, Alexander N; Wu, Ben; Prucnal, Paul R
2014-01-01
We propose an equivalent circuit model for photonic spike processing laser neurons with an embedded saturable absorber---a simulation model for photonic excitable lasers (SIMPEL). We show that by mapping the laser neuron rate equations into a circuit model, SPICE analysis can be used as an efficient and accurate engine for numerical calculations, capable of generalization to a variety of different laser neuron types found in literature. The development of this model parallels the Hodgkin--Huxley model of neuron biophysics, a circuit framework which brought efficiency, modularity, and generalizability to the study of neural dynamics. We employ the model to study various signal-processing effects such as excitability with excitatory and inhibitory pulses, binary all-or-nothing response, and bistable dynamics.
Research Status and Development Trends of Bearingless Brushless DC Motor%无轴承无刷直流电机研究现状及发展趋势
Institute of Scientific and Technical Information of China (English)
刘奕辰; 朱熀秋
2014-01-01
A bearingless brushless DC motor is a new type of high performance motor , which integrates the function of magnetic bearings into a brushless DC motor .It has the characteristic of no friction , no wear , high speed , long service life of the magnetic bearings , and also has the advantages of high efficiency , small volume, simple structure of the brushless DC motor , and it has a potential vast development and application prospects .In this paper , the motor structure of the bearingless brushless DC and the principle of suspension force generation were introduced .A comprehensive overview of the bearingless brushless DC motors was presented , with particular emphasis on the motor structure and the control strategy analysis .On the basis of the superiority and the existence problems of the bearingless brushless DC , the research development trend of the bearingless brushless DC motor was analyzed in this paper .The results provided the reference for the fur-ther study on the bearingless brushless DC motor.%无轴承无刷直流电机是一种高性能的新型电机，它将无刷直流电机和磁悬浮轴承功能集成一体，使其不仅具备磁轴承无摩擦、无磨损、高速度、寿命长等特点，还具有无刷直流电机的效率高、体积小、结构简单的优势，潜在发展和应用前景非常广阔。本文介绍无轴承无刷直流电机的结构特点、悬浮力产生的原理，从电机结构、控制策略方面分析了无轴承无刷直流电机的国内外发展现状，并根据无轴承无刷直流电机的优势及存在的问题，分析了未来无轴承无刷直流电机的研究发展趋势，为今后进一步开展无轴承无刷直流电机的研究提供参考。
Analysis of DC output voltage ripple in an electromagnetic doubly salient brushless DC generator
Institute of Scientific and Technical Information of China (English)
WANG Li; YAN Yangguang; CAO Xiaoqing; MENG Xiaoli
2007-01-01
Considering the salient pole and high magnetic nonlinearity of the electromagnetic doubly salient (EMDS)DC generator,a 12/8 pole prototype EMDS generator is designed and calculated using a 2-D finite element method (FEM).The phenomenon is analyzed and that the phase voltage wave changes between 120°and 180°.The influence of the exciting current and armature reaction on the DC voltage ripple of the generator is discussed in detail.and the nonlinear rules are gained that DC voltage rippie changes accordingly.The theoretical analysis is verified by the simulation and expefimental results.The results are helpful for the optimal design of the generator and the optimal control of excitingwinding.We conelude mat the filter-capacitance of the rectifier can be designed.
Panigrahy, Rina
2012-01-01
There is a vast supply of prior art that study models for mental processes. Some studies in psychology and philosophy approach it from an inner perspective in terms of experiences and percepts. Others such as neurobiology or connectionist-machines approach it externally by viewing the mind as complex circuit of neurons where each neuron is a primitive binary circuit. In this paper, we also model the mind as a place where a circuit grows, starting as a collection of primitive components at birth and then builds up incrementally in a bottom up fashion. A new node is formed by a simple composition of prior nodes when we undergo a repeated experience that can be described by that composition. Unlike neural networks, however, these circuits take "concepts" or "percepts" as inputs and outputs. Thus the growing circuits can be likened to a growing collection of lambda expressions that are built on top of one another in an attempt to compress the sensory input as a heuristic to bound its Kolmogorov Complexity.
Optimizing of Commutation Torque Ripple Strategy in Brushless DC Motor%BLDCM换相转矩脉动的优化策略
Institute of Scientific and Technical Information of China (English)
王晓锋; 林伟
2014-01-01
First of all, this article creates the mathematical model of blushless DC Motor.Secondly, analyze the reduction theory of commutation torque ripple. Finally, put forward a strategy to reduce the commutation torque ripple from the low-speed level and high-speed level.This method guarantee equal between current decline rate of shutdown phase and current rising rate of opening phase during commutation, thus keep the current of un-commutation stable.Build a real brushless DC motor control platform for experimental verification,the proposed strategy of brushless DC motor commutation torque ripple is suppressed effectively.%首先建立了无刷直流电机(Brushless direct current motor, BLDCM)的数学模型，然后分析了换相转矩脉动的抑制原理，最后提出了低速阶段和高速阶段抑制换相转矩脉动的策略。此方法保证在换相期间，关断相的电流下降率和开通相的电流上升率绝对值相等，继而保证在换相期间非换相相电流保持恒定。搭建了实际直流无刷电机控制平台并进行实验验证，所提出的策略有效地抑制了直流无刷电机换相转矩脉动。
Brushless DC motor control system based on expert PID%基于专家PID的直流无刷电机控制系统＊
Institute of Scientific and Technical Information of China (English)
张浩; 吴新开
2015-01-01
由于直流无刷电机存在时变性、非线性、不确定性、难以建模等特点，采用常规的PID很难达到理想的控制效果。通过专家PID控制理论并结合实践研究，提出一种高性能的速度控制方案。基于多旋翼飞行器常用的无刷电机转速控制这一实验平台，采用编码器测速实现无刷电机的闭环控制。无刷电机速度PID控制器的引入，开辟了多旋翼飞行器电机控制和姿态控制的新思路。%The brushless DC motor has the characteristics of time varing, nonliner, uncertainty and hardly modeling, so it is difficult to obtain ideal control effect by using conventional PID control. It is hoped to find a high-performance speed control scheme through the theory and practical research of expert PID. Based on the experiment platform of commonly used brushless motor speed control for multi rotor aircraft, the encoder is applied to measure the rotational speed and realize its closed-loop control. The introduction of brushless motor speed PID controller has opened up new ideas for motor control and attitude control of multi rotor aircraft.
Brushless DC motor control system based on expert PID%基于专家PID的直流无刷电机控制系统＊
Institute of Scientific and Technical Information of China (English)
张浩; 吴新开
2015-01-01
The brushless DC motor has the characteristics of time varing, nonliner, uncertainty and hardly modeling, so it is difficult to obtain ideal control effect by using conventional PID control. It is hoped to find a high-performance speed control scheme through the theory and practical research of expert PID. Based on the experiment platform of commonly used brushless motor speed control for multi rotor aircraft, the encoder is applied to measure the rotational speed and realize its closed-loop control. The introduction of brushless motor speed PID controller has opened up new ideas for motor control and attitude control of multi rotor aircraft.%由于直流无刷电机存在时变性、非线性、不确定性、难以建模等特点，采用常规的PID很难达到理想的控制效果。通过专家PID控制理论并结合实践研究，提出一种高性能的速度控制方案。基于多旋翼飞行器常用的无刷电机转速控制这一实验平台，采用编码器测速实现无刷电机的闭环控制。无刷电机速度PID控制器的引入，开辟了多旋翼飞行器电机控制和姿态控制的新思路。
GABAergic circuit dysfunctions in neurodevelopmental disorders
Directory of Open Access Journals (Sweden)
Bidisha eChattopadhyaya
2012-05-01
Full Text Available GABAergic interneurons control neuronal excitability, integration, and plasticity. Further, they regulate the generation of temporal synchrony and oscillatory behavior among networks of pyramidal neurons. Such oscillations within and across neural systems are believed to serve various complex functions, such as perception, movement initiation, and memory. Alterations in the development of GABAergic circuits have been implicated in various brain diseases with neurodevelopmental origin. Here, we highlight recent studies suggesting a role for alterations of GABA transmission in the pathophysiology of two neurodevelopmental diseases, schizophrenia and autism. We further discuss how manipulations of GABA signaling may be used for novel therapeutic interventions.
Aplicació docent d'autòmats programables al posicionament d'eixos mitjançant motor brushless
López López, Fernando
2004-01-01
Premi al millor Projecte de Fi de Carrera presentat durant el curs 2003-2004 en l'àmbit de Mecatrònica que atorga TECNOTRANS L’objectiu del present projecte, és la fabricació d’una maqueta amb finalitat docent, que exposi el funcionament d’un sistema de posicionament d’eixos compost per un motor brushless, resolver, variador de velocitat i autòmat programable amb mòdul controlador d’eixos. Per aconseguir això, s’ha muntat un eix de desplaçament lineal d’un metre de longitud, al ...
无刷直流电机的智能控制研究%Research on the Intelligent Control of the Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
文卫
2011-01-01
无刷直流电机具有交流电机结构简单,运行可靠,维护方便等优点,又具有直流电机那样良好的调速性能而无机械换向器等优势,得到广泛应用.针对大多数无刷直流电机位置伺服系统采用的是PID控制方式,此控制方式存在系统参数发生变化或带有非线性负载时,其稳态输出特性变差,难以获得满意的控制效果的情况,本文在分析无刷直流电机的模型后,提出一种能根据跟踪误差大小,利用模式切换开关自动切换到PID控制或滑模变结构控制的智能控制方法,从而实现无刷直流电机转子转速的快响应、低超调和高精度控制.%The brushless DC motor has some AC motor advantages in the simple structure, reliable operation and convenient maintenance, and also has the DC motor advantages that good performance of speed and no mechanical commutation, so it is widely used. For most of the brushless DC motor position servo system uses a PID control mode. With this control mode the steady - state output characteristics would become poor when system parameter changes or with nonlinear load, and it is difficult to obtain satisfactory control effect. After analyzed the model of brushless DC motor, this article presented an intelligent control method that can utilize mode switch automatically switch to PID control or sliding mode variable structure control according to the tracking error size, so as to realize the brushless DC motor rotor speed quick response, low overshoot and high precision control.
Adjustment of Phase Change Opportunity in Brushless DC Motor%直流无刷电机换相时机的调整
Institute of Scientific and Technical Information of China (English)
刘佳峰; 谢杨华
2006-01-01
直流无刷电机BLDCM(Brushless DC Motor)采用电子换相代替机械换相,兼有交流电机和直流电机的优点.提出了在磁场畸变的情况下,应将直流无刷电机换相时机从几何中性线处调整到物理中型线处.仿真结果表明:此调整方案可使电机的电磁转矩提高约10%.
无位置传感器无刷直流电机的DSP控制%DSP Control of Brushless DC Motor Without Position Sensor
Institute of Scientific and Technical Information of China (English)
王宏伟; 梁晖
2005-01-01
设计了一种无位置传感器无刷直流电机(Brushless DC Motor,简称BLDCM)的变频调速系统.该系统基于PS21255智能功率模块(IPM)和TMS320LF2407A数字信号处理器(DSP),采用反电势法实现了WPS的BLDCM控制.整个系统集成度高,控制灵活,稳定性好.实验结果表明,该系统运行性能良好.
Design motor control system of the main circuit and driver circuit%电机控制系统主电路及驱动电路的设计
Institute of Scientific and Technical Information of China (English)
阴丽华; 曾显恒
2014-01-01
Motor body chosen in this article brushless DC motor using three phase windings star connected while power device is composed of an inverter bridge circuit. The article describes the control system hardware circuit design process. In EasyARM2100 development board for the core of the control unit, the main circuit and the drive unit line described, and hardware design also made corresponding explanation.%本文中选用的无刷直流电动机的电机本体采用星形连接的三相对称绕组，同时功率器件组成的逆变器为桥式电路。文章主要叙述了控制系统的硬件电路设计过程。以EasyARM2100开发板为核心的控制单元，主电路及驱动单元行了阐述，并对硬件设计也作出了相应的解释。
Chaotic memristive circuit: equivalent circuit realization and dynamical analysis
Institute of Scientific and Technical Information of China (English)
Bao Bo-Cheng; Xu Jian-Ping; Zhou Guo-Hua; Ma Zheng-Hua; Zou Ling
2011-01-01
In this paper,a practical equivalent circuit of an active flux-controlled memristor characterized by smooth piecewise-quadratic nonlinearity is designed and an experimental chaotic memristive circuit is implemented.The chaotic memristive circuit has an equilibrium set and its stability is dependent on the initial state of the memristor.The initial state-dependent and the circuit parameter-dependent dynamics of the chaotic memristive circuit are investigated via phase portraits,bifurcation diagrams and Lyapunov exponents.Both experimental and simulation results validate the proposed equivalent circuit realization of the active flux-controlled memristor.
Circuit Quantum Electrodynamics
Bishop, Lev S
2010-01-01
Circuit Quantum Electrodynamics (cQED), the study of the interaction between superconducting circuits behaving as artificial atoms and 1-dimensional transmission-line resonators, has shown much promise for quantum information processing tasks. For the purposes of quantum computing it is usual to approximate the artificial atoms as 2-level qubits, and much effort has been expended on attempts to isolate these qubits from the environment and to invent ever more sophisticated control and measurement schemes. Rather than focussing on these technological aspects of the field, this thesis investigates the opportunities for using these carefully engineered systems for answering questions of fundamental physics.
Electronic circuits fundamentals & applications
Tooley, Mike
2015-01-01
Electronics explained in one volume, using both theoretical and practical applications.New chapter on Raspberry PiCompanion website contains free electronic tools to aid learning for students and a question bank for lecturersPractical investigations and questions within each chapter help reinforce learning Mike Tooley provides all the information required to get to grips with the fundamentals of electronics, detailing the underpinning knowledge necessary to appreciate the operation of a wide range of electronic circuits, including amplifiers, logic circuits, power supplies and oscillators. The
Argyle, Andrew
2009-01-01
Step-by-step instructions for making your own PCBs at home. Making your own printed circuit board (PCB) might seem a daunting task, but once you master the steps, it's easy to attain professional-looking results. Printed circuit boards, which connect chips and other components, are what make almost all modern electronic devices possible. PCBs are made from sheets of fiberglass clad with copper, usually in multiplelayers. Cut a computer motherboard in two, for instance, and you'll often see five or more differently patterned layers. Making boards at home is relatively easy
Kishore, K Lal
2008-01-01
Second Edition of the book Electronic Circuit Analysis is brought out with certain new Topics and reorganization of text matter into eight units. With addition of new topics, syllabi of many universities in this subject can be covered. Besides this, the book can also meet the requirements of M.Sc (Electronics), AMIETE, AMIE (Electronics) courses. Text matter is improved thoroughly. New topics like frequency effects in multistage amplifiers, amplifier circuit analysis, design of high frequency amplifiers, switching regulators, voltage multipliers, Uninterrupted Power Supplies (UPS), and Switchi
Inrush Current Control Circuit
Cole, Steven W. (Inventor)
2002-01-01
An inrush current control circuit having an input terminal connected to a DC power supply and an output terminal connected to a load capacitor limits the inrush current that charges up the load capacitor during power up of a system. When the DC power supply applies a DC voltage to the input terminal, the inrush current control circuit produces a voltage ramp at the load capacitor instead of an abrupt DC voltage. The voltage ramp results in a constant low level current to charge up the load capacitor, greatly reducing the current drain on the DC power supply.
Circuit design for reliability
Cao, Yu; Wirth, Gilson
2015-01-01
This book presents physical understanding, modeling and simulation, on-chip characterization, layout solutions, and design techniques that are effective to enhance the reliability of various circuit units. The authors provide readers with techniques for state of the art and future technologies, ranging from technology modeling, fault detection and analysis, circuit hardening, and reliability management. Provides comprehensive review on various reliability mechanisms at sub-45nm nodes; Describes practical modeling and characterization techniques for reliability; Includes thorough presentation of robust design techniques for major VLSI design units; Promotes physical understanding with first-principle simulations.
Younis, Mohammad I.
2016-03-10
Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi- frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.
A neural command circuit for grooming movement control.
Hampel, Stefanie; Franconville, Romain; Simpson, Julie H; Seeds, Andrew M
2015-09-07
Animals perform many stereotyped movements, but how nervous systems are organized for controlling specific movements remains unclear. Here we use anatomical, optogenetic, behavioral, and physiological techniques to identify a circuit in Drosophila melanogaster that can elicit stereotyped leg movements that groom the antennae. Mechanosensory chordotonal neurons detect displacements of the antennae and excite three different classes of functionally connected interneurons, which include two classes of brain interneurons and different parallel descending neurons. This multilayered circuit is organized such that neurons within each layer are sufficient to specifically elicit antennal grooming. However, we find differences in the durations of antennal grooming elicited by neurons in the different layers, suggesting that the circuit is organized to both command antennal grooming and control its duration. As similar features underlie stimulus-induced movements in other animals, we infer the possibility of a common circuit organization for movement control that can be dissected in Drosophila.
ESD analog circuits and design
Voldman, Steven H
2014-01-01
A comprehensive and in-depth review of analog circuit layout, schematic architecture, device, power network and ESD design This book will provide a balanced overview of analog circuit design layout, analog circuit schematic development, architecture of chips, and ESD design. It will start at an introductory level and will bring the reader right up to the state-of-the-art. Two critical design aspects for analog and power integrated circuits are combined. The first design aspect covers analog circuit design techniques to achieve the desired circuit performance. The second and main aspect pres
Unstable oscillators based hyperchaotic circuit
DEFF Research Database (Denmark)
Murali, K.; Tamasevicius, A.; G. Mykolaitis, A.;
1999-01-01
A simple 4th order hyperchaotic circuit with unstable oscillators is described. The circuit contains two negative impedance converters, two inductors, two capacitors, a linear resistor and a diode. The Lyapunov exponents are presented to confirm hyperchaotic nature of the oscillations in the circ...... in the circuit. The performance of the circuit is investigated by means of numerical integration of appropriate differential equations, PSPICE simulations, and hardware experiment.......A simple 4th order hyperchaotic circuit with unstable oscillators is described. The circuit contains two negative impedance converters, two inductors, two capacitors, a linear resistor and a diode. The Lyapunov exponents are presented to confirm hyperchaotic nature of the oscillations...
Quantum secure circuit evaluation
Institute of Scientific and Technical Information of China (English)
CHEN Huanhuan; LI Bin; ZHUANG Zhenquan
2004-01-01
In order to solve the problem of classical secure circuit evaluation, this paper proposes a quantum approach. In this approach, the method of inserting redundant entangled particles and quantum signature has been employed to strengthen the security of the system. Theoretical analysis shows that our solution is secure against classical and quantum attacks.
Superconducting Quantum Circuits
Majer, J.B.
2002-01-01
This thesis describes a number of experiments with superconducting cir- cuits containing small Josephson junctions. The circuits are made out of aluminum islands which are interconnected with a very thin insulating alu- minum oxide layer. The connections form a Josephson junction. The current trough
Bioluminescent bioreporter integrated circuit
Energy Technology Data Exchange (ETDEWEB)
Simpson, Michael L. (Knoxville, TN); Sayler, Gary S. (Blaine, TN); Paulus, Michael J. (Knoxville, TN)
2000-01-01
Disclosed are monolithic bioelectronic devices comprising a bioreporter and an OASIC. These bioluminescent bioreporter integrated circuit are useful in detecting substances such as pollutants, explosives, and heavy-metals residing in inhospitable areas such as groundwater, industrial process vessels, and battlefields. Also disclosed are methods and apparatus for environmental pollutant detection, oil exploration, drug discovery, industrial process control, and hazardous chemical monitoring.
The Study of Permanent Magnet Brushless DC Motor%对永磁无刷直流电机的研究
Institute of Scientific and Technical Information of China (English)
杨杰城
2016-01-01
随着我国科技不断发展，永磁无刷直流电机已成为电力电子一体化高科技产品，凭借其结构简单、运行可靠、效率高，在航天、医学、家用民用产品制作中得到广泛应用。文章对永磁无刷直流电机设计、控制以及建模方法进行分析，展现其对生产起到的重要作用。%With the continuous development of science and technology in our country,permanent magnet brushless dc motor has become power and electricity integration high-tech products.With its simple structure,reliable operation,high efficiency,it has been widely used in the aerospace,medical,household production.In this paper,the design,control,and modeling methods of permanent magnet brushless dc motor are analyzed.
An energy-saving fan with brushless motor design%一款节能风扇用无刷电机的设计
Institute of Scientific and Technical Information of China (English)
唐雷
2013-01-01
National efforts to promote "energy saving" today, fans still widespread use of low-efficiency low-power single-phase induction motors. This design features selected with efficient three-phase brushless motor, replace the single phase capacitor induction motor, under controlled conditions in terms of cost, the design of three-phase brushless motor efficiency dramatically. Will promote the use of good social benefits .%国家大力提倡“节能减排”的今天，电风扇仍然普遍使用低效率的小功率单相感应电机。本设计选取具备高效特性的三相无刷电机，取代单相电容感应电机，在成本可控的条件下，所设计的三相无刷电机，效率得到大幅提升。推广使用将获得良好的社会效益。
Resistor Combinations for Parallel Circuits.
McTernan, James P.
1978-01-01
To help simplify both teaching and learning of parallel circuits, a high school electricity/electronics teacher presents and illustrates the use of tables of values for parallel resistive circuits in which total resistances are whole numbers. (MF)
DEFF Research Database (Denmark)
Lindberg, Erik; Murali, K.; Tamacevicius, Arunas
2006-01-01
The state equations of the LMT circuit are modeled as a dedicated analogue computer circuit and solved by means of PSpice. The nonlinear part of the system is studied. Problems with the PSpice program are presented....
Lim, Edward C
1982-01-01
Excited States, Volume 6 is a collection of papers that discusses the excited states of molecules. The first paper discusses the linear polyene electronic structure and potential surfaces, considering both the theoretical and experimental approaches in such electronic states. This paper also reviews the theory of electronic structure and cites some experimental techniques on polyene excitations, polyene spectroscopic phenomenology, and those involving higher states of polyenes and their triplet states. Examples of these experimental studies of excited states involve the high-resolution one-pho
Lim, Edward C
2013-01-01
Excited States, Volume 2 is a collection of papers that deals with molecules in the excited states. The book describes the geometries of molecules in the excited electronic states. One paper describes the geometries of a diatomic molecule and of polyatomic molecules; it also discusses the determination of the many excited state geometries of molecules with two, three, or four atoms by techniques similar to diatomic spectroscopy. Another paper introduces an ordered theory related to excitons in pure and mixed molecular crystals. This paper also presents some experimental data such as those invo
1975-01-01
Technological information is presented electronic circuits and systems which have potential utility outside the aerospace community. Topics discussed include circuit components such as filters, converters, and integrators, circuits designed for use with specific equipment or systems, and circuits designed primarily for use with optical equipment or displays.
Diode, transistor & fet circuits manual
Marston, R M
2013-01-01
Diode, Transistor and FET Circuits Manual is a handbook of circuits based on discrete semiconductor components such as diodes, transistors, and FETS. The book also includes diagrams and practical circuits. The book describes basic and special diode characteristics, heat wave-rectifier circuits, transformers, filter capacitors, and rectifier ratings. The text also presents practical applications of associated devices, for example, zeners, varicaps, photodiodes, or LEDs, as well as it describes bipolar transistor characteristics. The transistor can be used in three basic amplifier configuration
Positive fractional linear electrical circuits
Kaczorek, Tadeusz
2013-10-01
The positive fractional linear systems and electrical circuits are addressed. New classes of fractional asymptotically stable and unstable electrical circuits are introduced. The Caputo and Riemann-Liouville definitions of fractional derivatives are used to analysis of the positive electrical circuits composed of resistors, capacitors, coils and voltage (current) sources. The positive fractional electrical and specially unstable different types electrical circuits are analyzed. Some open problems are formulated.
Static Switching Dynamic Buffer Circuit
Pandey, A. K.; R. A. Mishra; R. K. Nagaria
2013-01-01
We proposed footless domino logic buffer circuit. It minimizes redundant switching at the dynamic and the output nodes. The proposed circuit avoids propagation of precharge pulse to the output node and allows the dynamic node which saves power consumption. Simulation is done using 0.18 µm CMOS technology. We have calculated the power consumption, delay, and power delay product of the proposed circuit and compared the results with the existing circuits for different logic function, loading co...
Value Constraint and Monotone circuit
Kobayashi, Koji
2012-01-01
This paper talks about that monotone circuit is P-Complete. Decision problem that include P-Complete is mapping that classify input with a similar property. Therefore equivalence relation of input value is important for computation. But monotone circuit cannot compute the equivalence relation of the value because monotone circuit can compute only monotone function. Therefore, I make the value constraint explicitly in the input and monotone circuit can compute equivalence relation. As a result...
Bossen, Olaf
2011-01-01
We present a new type of calorimeter in which we couple an unknown heat capacity with the aid of Peltier elements to an electrical circuit. The use of an electrical inductance and an amplifier in the circuit allows us to achieve autonomous oscillations, and the measurement of the corresponding resonance frequency makes it possible to accurately measure the heat capacity with an intrinsic statistical error that decreases as ~t^{-3/2} with measuring time t, as opposed to a corresponding error ~t^{-1/2} in the conventional alternating current (a.c.) method to measure heat capacities. We have built a demonstration experiment to show the feasibility of the new technique, and we have tested it on a gadolinium sample at its transition to the ferromagnetic state.
Illuminating neural circuits and behaviour in Caenorhabditis elegans with optogenetics.
Fang-Yen, Christopher; Alkema, Mark J; Samuel, Aravinthan D T
2015-09-19
The development of optogenetics, a family of methods for using light to control neural activity via light-sensitive proteins, has provided a powerful new set of tools for neurobiology. These techniques have been particularly fruitful for dissecting neural circuits and behaviour in the compact and transparent roundworm Caenorhabditis elegans. Researchers have used optogenetic reagents to manipulate numerous excitable cell types in the worm, from sensory neurons, to interneurons, to motor neurons and muscles. Here, we show how optogenetics applied to this transparent roundworm has contributed to our understanding of neural circuits.
Engineering prokaryotic gene circuits
Michalodimitrakis, Konstantinos; Isalan, Mark
2009-01-01
Engineering of synthetic gene circuits is a rapidly growing discipline, currently dominated by prokaryotic transcription networks, which can be easily rearranged or rewired to give different output behaviours. In this review, we examine both a rational and a combinatorial design of such networks and discuss progress on using in vitro evolution techniques to obtain functional systems. Moving beyond pure transcription networks, more and more networks are being implemented at the level of RNA, t...
Electronic devices and circuits
Kishore, K Lal
2008-01-01
This book is written in a simple lucid Language along with derivation of equations and supported by numerous solved problems to help the student to understand the concepts clearly.Advances in Miniaturization of Electronic Systems by ever increasing packaging densities on Integrated Circuits has made it very essential for thorough Knowledge of the concepts, phenomenon, characteristics and behaviour of semiconductor Devices for students and professionals.
Cartography of serotonergic circuits.
Sparta, Dennis R; Stuber, Garret D
2014-08-01
Serotonin is an essential neuromodulator, but the precise circuit connectivity that regulates serotonergic neurons has not been well defined. Using rabies virus tracing strategies Weissbourd et al. (2014) and Pollak Dorocic et al. (2014) in this issue of Neuron and Ogawa et al. (2014) in Cell Reports provide a comprehensive map of the inputs to serotonergic neurons, highlighting the complexity and diversity of potential upstream cellular regulators.
PARTICLE BEAM TRACKING CIRCUIT
Anderson, O.A.
1959-05-01
>A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)
A scalable piezoelectric impulse-excited energy harvester for human body excitation
Pillatsch, P.; Yeatman, E. M.; Holmes, A. S.
2012-11-01
Harvesting energy from low-frequency and non-harmonic excitations typical of human motion presents specific challenges. While resonant devices do have an advantage in environments where the excitation frequency is constant, and while they can make use of the entire proof mass travel range in the case of excitation amplitudes that are smaller than the internal displacement limit, they are not suitable for body applications since the frequencies are random and the amplitudes tend to be larger than the device size. In this paper a piezoelectric, impulse-excited approach is presented. A cylindrical proof mass actuates an array of piezoelectric bi-morph beams through magnetic attraction. After the initial excitation these transducers are left to vibrate at their natural frequency. This increases the operational frequency range as well as the electromechanical coupling. The principle of impulse excitation is discussed and a centimetre-scale functional model is introduced as a proof of concept. The obtained data show the influence of varying the frequency, acceleration and proof mass. Finally, a commercially available integrated circuit for voltage regulation is tested. At a frequency of 2 Hz and an acceleration of 2.7 m s-2 a maximal power output of 2.1 mW was achieved.
Institute of Scientific and Technical Information of China (English)
樊贝; 薛冰
2012-01-01
为适应大功率风机和泵类负载的调速性能,提出无刷双馈电动机的技术方案,并利用Matlab/Simulink建立无刷双馈电动机的一般模型进行动态仿真。仿真结果显示,无刷双馈电动机在单馈异步运行状态下,具有良好的异步电动机的启动运行特性。在双馈同步运行状态下,具有普通同步电动机转速特性,为进一步深入研究无刷双馈电动机的控制策略提供了参考。重点介绍无刷双馈电动机的结构特点和工作原理。%In order to adapt the speed regulation performance of big power blower and pump loading,the brushless doubly-fed motor＇s technology proposals are given out.And the dynamic simulation of brushless doubly-fed motor model is setted up based on Matlab/Simulink.The simulation results show that the brushless doubly-fed motor has good features of asynchronous motor starts and operates features under the states of single-fed asynchronous operation.It also has common synchronous motor speed features under doubly-fed synchronous operation state.These results provide reference for futher study on brushless doubly-fed motor＇s control strategy.And the structure features and working principle of brushless doubly-fed motor are introduced.
Energy Technology Data Exchange (ETDEWEB)
Amara, Y.
2001-12-01
Double excitation machines are synchronous machines where two excitation circuits coexist: one with permanent magnets and the other with windings. This study shows that double excitation allows to combine the advantages of synchronous machines with winded inductor with those of permanent magnet machines. This concept allows a better dimensioning of the converter-machine set and a better energy management. In order to allow the operation of permanent magnet machines over a wide range of speeds, it is necessary to have a magnetic reaction of the induced circuit of the same order than the excitation flux. On the other hand, the power factor is weaker and the power supply converter is over-dimensioned. The double excitation allows the permanent magnet machines to work over a large speed range with a better power factor, even when the magnetic reaction of the induced circuit is relatively weak with respect to the excitation flux. (J.S.)
Fundamental Atomtronic Circuit Elements
Lee, Jeffrey; McIlvain, Brian; Lobb, Christopher; Hill, Wendell T., III
2012-06-01
Recent experiments with neutral superfluid gases have shown that it is possible to create atomtronic circuits analogous to existing superconducting circuits. The goals of these experiments are to create complex systems such as Josephson junctions. In addition, there are theoretical models for active atomtronic components analogous to diodes, transistors and oscillators. In order for any of these devices to function, an understanding of the more fundamental atomtronic elements is needed. Here we describe the first experimental realization of these more fundamental elements. We have created an atomtronic capacitor that is discharged through a resistance and inductance. We will discuss a theoretical description of the system that allows us to determine values for the capacitance, resistance and inductance. The resistance is shown to be analogous to the Sharvin resistance, and the inductance analogous to kinetic inductance in electronics. This atomtronic circuit is implemented with a thermal sample of laser cooled rubidium atoms. The atoms are confined using what we call free-space atom chips, a novel optical dipole trap produced using a generalized phase-contrast imaging technique. We will also discuss progress toward implementing this atomtronic system in a degenerate Bose gas.
International Nuclear Information System (INIS)
4 main electromagnetic excitation processes of atomic nuclei in hot dense plasma are reviewed: the black body photon absorption, the electron inelastic scattering, the nuclear excitation by electron capture (NEEC effect) and the nuclear excitation by electron transition (NEET effect). Experimental results on Ta181m are commented and an experiment showing the NEEC effect on Fe57 is described. A model including all the phenomena of excitation and de-excitation of a nuclear state in plasma, has been developed. Predictions about the evolution of the life-time of a nuclear excited state as a function of the temperature and density are made. A complete calculation of the NEET effect of the first excited state of U235 in a local thermodynamic equilibrium plasma is presented. Some experimental works on the excitation of U235m in a laser-produced plasma are discussed. The NEET effect on Hg201 in a laser-produced plasma is also considered in both theoretical and experimental aspects
Changes to the shuttle circuits
GS Department
2011-01-01
To fit with passengers expectation, there will be some changes to the shuttle circuits as from Monday 10 October. See details on http://cern.ch/ShuttleService (on line on 7 October). Circuit No. 5 is cancelled as circuit No. 1 also stops at Bldg. 33. In order to guarantee shorter travel times, circuit No. 1 will circulate on Meyrin site only and circuit No. 2, with departures from Bldg. 33 and 500, on Prévessin site only. Site Services Section
Experimental determination of circuit equations
Shulman, Jason; Widjaja, Matthew; Gunaratne, Gemunu H
2013-01-01
Kirchhoff's laws offer a general, straightforward approach to circuit analysis. Unfortunately, use of the laws becomes impractical for all but the simplest of circuits. This work presents a novel method of analyzing direct current resistor circuits. It is based on an approach developed to model complex networks, making it appropriate for use on large, complicated circuits. It is unique in that it is not an analytic method. It is based on experiment, yet the approach produces the same circuit equations obtained by more traditional means.
Power system with an integrated lubrication circuit
Energy Technology Data Exchange (ETDEWEB)
Hoff, Brian D. (East Peoria, IL); Akasam, Sivaprasad (Peoria, IL); Algrain, Marcelo C. (Peoria, IL); Johnson, Kris W. (Washington, IL); Lane, William H. (Chillicothe, IL)
2009-11-10
A power system includes an engine having a first lubrication circuit and at least one auxiliary power unit having a second lubrication circuit. The first lubrication circuit is in fluid communication with the second lubrication circuit.
Integrated coherent matter wave circuits
International Nuclear Information System (INIS)
An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through their electric polarizability. Moreover, the source of coherent matter waves is a Bose-Einstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry
Memristor based startup circuit for self biased circuits
Das, Mangal; Singh, Amit Kumar; Rathi, Amit; Singhal, Sonal
2016-04-01
This paper presents the design of a Memristor based startup circuit for self biased circuits. Memristor has many advantages over conventional CMOS devices such as low leakage current at nanometer scale, easy to manufacture. In this work the switching characteristics of memristor is utilized. First the theoretical equations describing the switching behavior of memristor are investigated. To prove the switching capability of Memristor, a startup circuit based on memristor is proposed which uses series combination of Memristor and capacitor. Proposed circuit is compared with the previously reported MOSFET based startup circuits. Comparison of different circuits was done to validate the results. Simulation results show that memristor based circuit can attain on (I = 12.94 µA) to off state (I = 1 .2 µA) in 25 ns while the MOSFET based startup circuits take on (I = 14.19 µA) to off state (I = 1.4 µA) in more than 90 ns. The benefit comes in terms of area because the number of components used in the circuit are lesser than the conventional startup circuits.
Neural circuit dysfunction in schizophrenia: Insights from animal models.
Sigurdsson, T
2016-05-01
Despite decades of research, the neural circuit abnormalities underlying schizophrenia remain elusive. Although studies on schizophrenia patients have yielded important insights they have not been able to fully reveal the details of how neural circuits are disrupted in the disease, which is essential for understanding its pathophysiology and developing new treatment strategies. Animal models of schizophrenia are likely to play an important role in this effort. Such models allow neural circuit dysfunction to be investigated in detail and the role of risk factors and pathophysiological mechanisms to be experimentally assessed. The goal of this review is to summarize what we have learned from electrophysiological studies that have examined neural circuit function in animal models of schizophrenia. Although these studies have revealed diverse manifestations of neural circuit dysfunction spanning multiple levels of analysis, common themes have nevertheless emerged across different studies and animal models, revealing a core set of neural circuit abnormalities. These include an imbalance between excitation and inhibition, deficits in synaptic plasticity, disruptions in local and long-range synchrony and abnormalities in dopaminergic signaling. The relevance of these findings to the pathophysiology of the disease is discussed, as well as outstanding questions for future research.
Asynchronous Rate Chaos in Spiking Neuronal Circuits
Harish, Omri; Hansel, David
2015-01-01
The brain exhibits temporally complex patterns of activity with features similar to those of chaotic systems. Theoretical studies over the last twenty years have described various computational advantages for such regimes in neuronal systems. Nevertheless, it still remains unclear whether chaos requires specific cellular properties or network architectures, or whether it is a generic property of neuronal circuits. We investigate the dynamics of networks of excitatory-inhibitory (EI) spiking neurons with random sparse connectivity operating in the regime of balance of excitation and inhibition. Combining Dynamical Mean-Field Theory with numerical simulations, we show that chaotic, asynchronous firing rate fluctuations emerge generically for sufficiently strong synapses. Two different mechanisms can lead to these chaotic fluctuations. One mechanism relies on slow I-I inhibition which gives rise to slow subthreshold voltage and rate fluctuations. The decorrelation time of these fluctuations is proportional to the time constant of the inhibition. The second mechanism relies on the recurrent E-I-E feedback loop. It requires slow excitation but the inhibition can be fast. In the corresponding dynamical regime all neurons exhibit rate fluctuations on the time scale of the excitation. Another feature of this regime is that the population-averaged firing rate is substantially smaller in the excitatory population than in the inhibitory population. This is not necessarily the case in the I-I mechanism. Finally, we discuss the neurophysiological and computational significance of our results. PMID:26230679
Lim, Edward C
2013-01-01
Excited States, Volume 4 is a collection of papers that deals with the excited states of molecular activity. One paper investigates the resonance Raman spectroscopy as the key to vibrational-electronic coupling. This paper reviews the basic theory of Raman scattering; it also explains the derivation of the Raman spectra, excitation profiles, and depolarization ratios for simple resonance systems. Another paper reviews the magnetic properties of triplet states, including the zero-field resonance techniques, the high-field experiments, and the spin Hamiltonian. This paper focuses on the magnetic
Merritt, Scott; Krainak, Michael
2016-01-01
Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.
Optoelectronics circuits manual
Marston, R M
1999-01-01
This manual is a useful single-volume guide specifically aimed at the practical design engineer, technician, and experimenter, as well as the electronics student and amateur. It deals with the subject in an easy to read, down to earth, and non-mathematical yet comprehensive manner, explaining the basic principles and characteristics of the best known devices, and presenting the reader with many practical applications and over 200 circuits. Most of the ICs and other devices used are inexpensive and readily available types, with universally recognised type numbers.The second edition
Electronics circuits and systems
Bishop, Owen
2007-01-01
The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Each chapter ends with a set
Electric circuits problem solver
REA, Editors of
2012-01-01
Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of electric circuits currently av
Gibson, J
2013-01-01
Most branches of organizing utilize digital electronic systems. This book introduces the design of such systems using basic logic elements as the components. The material is presented in a straightforward manner suitable for students of electronic engineering and computer science. The book is also of use to engineers in related disciplines who require a clear introduction to logic circuits. This third edition has been revised to encompass the most recent advances in technology as well as the latest trends in components and notation. It includes a wide coverage of application specific integrate
Electronics circuits and systems
Bishop, Owen
2011-01-01
The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Ea
Carr, Joseph
1996-01-01
The linear IC market is large and growing, as is the demand for well trained technicians and engineers who understand how these devices work and how to apply them. Linear Integrated Circuits provides in-depth coverage of the devices and their operation, but not at the expense of practical applications in which linear devices figure prominently. This book is written for a wide readership from FE and first degree students, to hobbyists and professionals.Chapter 1 offers a general introduction that will provide students with the foundations of linear IC technology. From chapter 2 onwa
Nano integrated circuit process
Energy Technology Data Exchange (ETDEWEB)
Yoon, Yung Sup
2004-02-15
This book contains nine chapters, which are introduction of manufacture of semiconductor chip, oxidation such as Dry-oxidation, wet oxidation, oxidation model and oxide film, diffusion like diffusion process, diffusion equation, diffusion coefficient and diffusion system, ion implantation, including ion distribution, channeling, multiimplantation and masking and its system, sputtering such as CVD and PVD, lithography, wet etch and dry etch, interconnection and flattening like metal-silicon connection, silicide, multiple layer metal process and flattening, an integrated circuit process, including MOSFET and CMOS.
Optically controllable molecular logic circuits
Energy Technology Data Exchange (ETDEWEB)
Nishimura, Takahiro, E-mail: t-nishimura@ist.osaka-u.ac.jp; Fujii, Ryo; Ogura, Yusuke; Tanida, Jun [Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 (Japan)
2015-07-06
Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.
Optically controllable molecular logic circuits
International Nuclear Information System (INIS)
Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals
Sequential circuit design for radiation hardened multiple voltage integrated circuits
Energy Technology Data Exchange (ETDEWEB)
Clark, Lawrence T. (Phoenix, AZ); McIver, III, John K. (Albuquerque, NM)
2009-11-24
The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.
Copelli, Mauro
2007-01-01
When a simple excitable system is continuously stimulated by a Poissonian external source, the response function (mean activity versus stimulus rate) generally shows a linear saturating shape. This is experimentally verified in some classes of sensory neurons, which accordingly present a small dynamic range (defined as the interval of stimulus intensity which can be appropriately coded by the mean activity of the excitable element), usually about one or two decades only. The brain, on the other hand, can handle a significantly broader range of stimulus intensity, and a collective phenomenon involving the interaction among excitable neurons has been suggested to account for the enhancement of the dynamic range. Since the role of the pattern of such interactions is still unclear, here we investigate the performance of a scale-free (SF) network topology in this dynamic range problem. Specifically, we study the transfer function of disordered SF networks of excitable Greenberg-Hastings cellular automata. We obser...
Designer gene circuits for basic science, engineering, and medicine /
Prindle, Arthur
2014-01-01
Gene regulatory networks lay at the foundation of biological function and are responsible for driving the diverse cellular decision making processes required to sustain life. Developing a comprehensive understanding of cellular function will require a quantitative description of the dynamics of these underlying interactions. The ability to design synthetic gene circuits offers the exciting prospect of prototyping new genetic subsystems inspired by the inherently complex networks of natural or...
Evolution of Quantum State for Mesoscopic Circuits with Dissipation
Institute of Scientific and Technical Information of China (English)
WAN Hua-Ming; LUO Hai-Mei; WANG Yi-Fan
2005-01-01
Based on the maximum entropy principle, we present a density matrix of mesoscopic RLC circuit to make it possible to analyze the connection of the initial condition with temperature. Our results show that the quantum state evolution is closely related to the initial condition, and that the system evolves to generalized coherent state if it is in ground state initially, and evolves to squeezed state if it is in excited state initially.
Plasmonic nanopatch array for optical integrated circuit applications
Shi-Wei Qu; Zai-Ping Nie
2013-01-01
Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will def...
High resolution capacitance detection circuit for rotor micro-gyroscope
Directory of Open Access Journals (Sweden)
Ming-Yuan Ren
2014-03-01
Full Text Available Conventional methods for rotor position detection of micro-gyroscopes include common exciting electrodes (single frequency and common sensing electrodes (frequency multiplex, but they have encountered some problems. So we present a high resolution and low noise pick-off circuit for micro-gyroscopes which utilizes the time multiplex method. The detecting circuit adopts a continuous-time current sensing circuit for capacitance measurement, and its noise analysis of the charge amplifier is introduced. The equivalent output noise power spectral density of phase-sensitive demodulation is 120 nV/Hz1/2. Tests revealed that the whole circuitry has a relative capacitance resolution of 1 × 10−8.
Bradley, William; Bird, Ross; Eldred, Dennis; Zook, Jon; Knowles, Gareth
2013-01-01
This work involved developing spacequalifiable switch mode DC/DC power supplies that improve performance with fewer components, and result in elimination of digital components and reduction in magnetics. This design is for missions where systems may be operating under extreme conditions, especially at elevated temperature levels from 200 to 300 degC. Prior art for radiation-tolerant DC/DC converters has been accomplished utilizing classical magnetic-based switch mode converter topologies; however, this requires specific shielding and component de-rating to meet the high-reliability specifications. It requires complex measurement and feedback components, and will not enable automatic re-optimization for larger changes in voltage supply or electrical loading condition. The innovation is a switch mode DC/DC power supply that eliminates the need for processors and most magnetics. It can provide a well-regulated voltage supply with a gain of 1:100 step-up to 8:1 step down, tolerating an up to 30% fluctuation of the voltage supply parameters. The circuit incorporates a ceramic core transformer in a manner that enables it to provide a well-regulated voltage output without use of any processor components or magnetic transformers. The circuit adjusts its internal parameters to re-optimize its performance for changes in supply voltage, environmental conditions, or electrical loading at the output
Johnson, Steven D.; Byers, Jerry W.; Martin, James A.
2012-01-01
A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.
无刷直流电动机不导通相电流分析%Analysis of Floating Phase Current in Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
王璞; 解恩; 翟猛
2012-01-01
分析了无刷直流电动机在三相六状态及不同的PWM方式下,绕组续流期间不导通相电流,并且指出各有不同.对常用的各种PWM方式通过原理分析及数学推导,得出不导通相电流存在的时段和幅值趋势.并通过实验测试,验证了分析结果.%The floating phase current during the free-wheeling and the difference of the brushless DC motor operating in three-phase-six-states and different PWM modes were analysed. The conclusion of existing time and amplitude trend were achieved by theory analysis and mathematical deduction of common PWM modes. The result was verified through the experiment test.
Energy Technology Data Exchange (ETDEWEB)
Luo, Shaohua [School of Automation, Chongqing University, Chongqing 400044 (China); Department of Mechanical Engineering, Chongqing Aerospace Polytechnic, Chongqing, 400021 (China); Wu, Songli [Department of Mechanical Engineering, Chongqing Aerospace Polytechnic, Chongqing, 400021 (China); Gao, Ruizhen [School of Automation, Chongqing University, Chongqing 400044 (China)
2015-07-15
This paper investigates chaos control for the brushless DC motor (BLDCM) system by adaptive dynamic surface approach based on neural network with the minimum weights. The BLDCM system contains parameter perturbation, chaotic behavior, and uncertainty. With the help of radial basis function (RBF) neural network to approximate the unknown nonlinear functions, the adaptive law is established to overcome uncertainty of the control gain. By introducing the RBF neural network and adaptive technology into the dynamic surface control design, a robust chaos control scheme is developed. It is proved that the proposed control approach can guarantee that all signals in the closed-loop system are globally uniformly bounded, and the tracking error converges to a small neighborhood of the origin. Simulation results are provided to show that the proposed approach works well in suppressing chaos and parameter perturbation.
Directory of Open Access Journals (Sweden)
Bangcheng Han
2013-01-01
Full Text Available We firstly report on an investigation into the unbalanced magnetic pull (UMP effect on the static stiffness models of radial active magnetic bearing (RAMB in brushless DC motor (BDCM in no-loaded and loaded conditions using the finite element method (FEM. The influences of the UMP on the force-control current, force-position, current stiffness, and position stiffness of RAMB are clarified in BDCM with 100 kW rated power. We found the position stiffness to be more susceptible to UMP. The primary source of UMP is the permanent magnets of BDCM. In addition, the performance of RAMB is affected by the UMP ripples during motor commutation and also periodically affected by the angular position of rotor. The characteristic curves of RAMB force versus control current (or rotor position and angular position of rotor affected by the UMP are given. The method is useful in design and optimization of RAMB in magnetically suspended BDCMs.
Directory of Open Access Journals (Sweden)
Tianxun Chen
2016-01-01
Full Text Available This paper presents a computationally efficient loss prediction procedure and thermal analysis of surface-mounted brushless AC permanent magnet (PM machine considering the UDDS driving duty cycle by using a lumped parameters’ thermal model. The accurate prediction of loss and its variation with load are essential for thermal analysis. Employing finite element analysis (FEA to determine loss at every load point would be computationally intensive. Here, the finite element analysis and/or experiment based computationally efficient winding copper and iron loss and permanent magnet (PM power loss models are employed to calculate the electromagnetic loss at every operation point, respectively. Then, the lumped parameter thermal method is used to analyse the thermal behaviour of the driving PM machine. Experiments have been carried out to measure the temperature distribution in a motor prototype. The calculation and experiment results are compared and discussed.
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
2010-10-01
... circuits through circuit controller. 236.13 Section 236.13 Transportation Other Regulations Relating to...; selection of signal control circuits through circuit controller. The control circuits of signals governing... circuit controller, or through the contacts of relay repeating the position of such circuit...
Adaptive GA-ADRC in Torque Ripple Reduction of Brushless DC Motor%自适应GA-ADRC在无刷直流电机转矩脉动抑制中的研究
Institute of Scientific and Technical Information of China (English)
刘慧博; 王静
2012-01-01
提出一种新型的无刷直流电机电磁转矩脉动抑制方法,该方法通过控制无刷直流电机导通相线电流跟踪给定电流来抑制电机的电磁转矩脉动.首先分析无刷直流电机数学模型,建立基于自适应遗传算法的无刷直流电机控制系统模型,由于自适应GA-ADRC控制器不需要无刷直流电机模型参数就可以实现干扰补偿,因此可以独立设计自适应GA-ADRC控制器.对文中所提出自适应GA-ADRC控制算法与经典PID控制算法的控制效果对比分析,控制效果明显优于传统PID控制效果.%The traditional PID control algorithm cannot satisfy the performance index of the brushless DC motor system because of the disadvantages of electromagnetic torque ripple, high complexity of detection method and control algorithm, and higher cost of current brushless DC motor. A novel electromagnet torque ripple suppression method of brushless DC motor was proposed in this paper. By virtue of controlling the conduction phase current of the brushless DC motor to track the given current, the motor electromagnet torque ripple was suppressed. The mathematical model of the motor was analyzed and a control system model of the brushless DC motor based on adaptive genetic algorithm was established. Since the adaptive GA-ADRC controller can realize disturbance compensation without model parameters of brushless DC motor, the GA-ADRC controller was independently designed. The comparative analysis shows that the proposed GA-ADRC control algorithm is obviously superior to that of the classical PID control algorithm.
Synthetic Biology: Integrated Gene Circuits
Nandagopal, Nagarajan; Michael B Elowitz
2011-01-01
A major goal of synthetic biology is to develop a deeper understanding of biological design principles from the bottom up, by building circuits and studying their behavior in cells. Investigators initially sought to design circuits “from scratch” that functioned as independently as possible from the underlying cellular system. More recently, researchers have begun to develop a new generation of synthetic circuits that integrate more closely with endogenous cellular processes. These approaches...
Quantum Circuits with Mixed States
Aharonov, Dorit; Kitaev, Alexei; Nisan, Noam
1998-01-01
We define the model of quantum circuits with density matrices, where non-unitary gates are allowed. Measurements in the middle of the computation, noise and decoherence are implemented in a natural way in this model, which is shown to be equivalent in computational power to standard quantum circuits. The main result in this paper is a solution for the subroutine problem: The general function that a quantum circuit outputs is a probabilistic function, but using pure state language, such a func...
Pharmacokinetics and RC Circuit Concepts
Cock, Mieke De; Janssen, Paul
2013-11-01
Most introductory physics courses include a chapter on RC circuits in which the differential equations for the charging and discharging of a capacitor are derived. A number of papers in this journal describe lab experiments dealing with the measurement of different parameters in such RC circuits. In this contribution, we report on a lab experiment we developed for students majoring in pharmacy, using RC circuits to simulate a pharmacokinetic process.
Designing Parity Preserving Reversible Circuits
Paul, Goutam; Chattopadhyay, Anupam; Chandak, Chander
2013-01-01
Making a reversible circuit fault-tolerant is much more difficult than classical circuit and there have been only a few works in the area of parity-preserving reversible logic design. Moreover, all of these designs are ad hoc, based on some pre-defined parity preserving reversible gates as building blocks. In this paper, we for the first time propose a novel and systematic approach towards parity preserving reversible circuits design. We provide some related theoretical results and give two a...
A Circuit to Demonstrate Phase Relationships in "RLC" Circuits
Sokol, P. E.; Warren, G.; Zheng, B.; Smith, P.
2013-01-01
We have developed a circuit to demonstrate the phase relationships between resistive and reactive elements in series "RLC" circuits. We utilize a differential amplifier to allow the phases of the three elements and the current to be simultaneously displayed on an inexpensive four channel oscilloscope. We have included a novel circuit…
Quantum Teleportation circuit using Matlab and Mathematica
Directory of Open Access Journals (Sweden)
Ms.Swati Sharma,
2010-08-01
Full Text Available This Paper describes a basic Quantum Teleportation circuit using mat lab Qlib tool. Teleportation is a new and exciting field of future communication. We know that security in data communication is a major concern nowadays. Among the encryption technologies that are available at present, shared key is the most reliable which depends on secure key generation and distribution. Teleportation/ ntanglement is a perfect solution for secure key generation and distribution, as for the no cloning theorem of quantum mechanics any attempt to intercept the key by the eavesdropper will be detectable immediately. A program is simulated with successful simulation which give successful transfer of random qubit to output and which governs perfect communication between Alice and Bob.
Quantum simulation with a boson sampling circuit
González Olivares, Diego; Peropadre, Borja; Aspuru-Guzik, Alán; García-Ripoll, Juan José
2016-08-01
In this work we study a system that consists of 2 M matter qubits that interact through a boson sampling circuit, i.e., an M -port interferometer, embedded in two different architectures. We prove that, under the conditions required to derive a master equation, the qubits evolve according to effective bipartite X Y spin Hamiltonians, with or without local and collective dissipation terms. This opens the door to the simulation of any bipartite spin or hard-core boson models and exploring dissipative phase transitions as the competition between coherent and incoherent exchange of excitations. We also show that in the purely dissipative regime this model has a large number of exact and approximate dark states, whose structure and decay rates can be estimated analytically. We finally argue that this system may be used for the adiabatic preparation of boson sampling states encoded in the matter qubits.
Memristor Circuits and Systems
Zidan, Mohammed A.
2015-05-01
Current CMOS-based technologies are facing design challenges related to the continuous scaling down of the minimum feature size, according to Moore’s law. Moreover, conventional computing architecture is no longer an effective way of fulfilling modern applications demands, such as big data analysis, pattern recognition, and vector processing. Therefore, there is an exigent need to shift to new technologies, at both the architecture and the device levels. Recently, memristor devices and structures attracted attention for being promising candidates for this job. Memristor device adds a new dimension for designing novel circuits and systems. In addition, high-density memristor-based crossbar is widely considered to be the essential element for future memory and bio-inspired computing systems. However, numerous challenges need to be addressed before the memristor genuinely replaces current memory and computing technologies, which is the motivation behind this research effort. In order to address the technology challenges, we begin by fabricating and modeling the memristor device. The devices fabricated at our local clean room enriched our understanding of the memristive phenomenon and enabled the experimental testing for our memristor-based circuits. Moreover, our proposed mathematical modeling for memristor behavior is an essential element for the theoretical circuit design stage. Designing and addressing the challenges of memristor systems with practical complexity, however, requires an extra step, which takes the form of a reliable and modular simulation platform. We, therefore, built a new simulation platform for the resistive crossbar, which can simulate realistic size arrays filled with real memory data. In addition, this simulation platform includes various crossbar nonidealities in order to obtain accurate simulation results. Consequently, we were able to address the significant challenges facing the high density memristor crossbar, as the building block for
Rosaria Marraffino
2014-01-01
You have always been told that electronic devices fear water. However, at the Surface Mount Devices (SMD) Workshop here at CERN all the electronic assemblies are cleaned with a machine that looks like a… dishwasher. The circuit dishwasher. Credit: Clara Nellist. If you think the image above shows a dishwasher, you wouldn’t be completely wrong. Apart from the fact that the whole pumping system and the case itself are made entirely from stainless steel and chemical resistant materials, and the fact that it washes electrical boards instead of dishes… it works exactly like a dishwasher. It’s a professional machine (mainly used in the pharmaceutical industry) designed to clean everything that can be washed with a water-based chemical soap. This type of treatment increases the lifetime of the electronic boards and therefore the LHC's reliability by preventing corrosion problems in the severe radiation and ozone environment of the LHC tunn...
Buckley, P M
1980-01-01
In the past, the teaching of electricity and electronics has more often than not been carried out from a theoretical and often highly academic standpoint. Fundamentals and basic concepts have often been presented with no indication of their practical appli cations, and all too frequently they have been illustrated by artificially contrived laboratory experiments bearing little relationship to the outside world. The course comes in the form of fourteen fairly open-ended constructional experiments or projects. Each experiment has associated with it a construction exercise and an explanation. The basic idea behind this dual presentation is that the student can embark on each circuit following only the briefest possible instructions and that an open-ended approach is thereby not prejudiced by an initial lengthy encounter with the theory behind the project; this being a sure way to dampen enthusiasm at the outset. As the investigation progresses, questions inevitably arise. Descriptions of the phenomena encounte...
Energy Technology Data Exchange (ETDEWEB)
Rohrer, Brandon Robinson; Rothganger, Fredrick H.; Verzi, Stephen J.; Xavier, Patrick Gordon
2010-09-01
The neocortex is perhaps the highest region of the human brain, where audio and visual perception takes place along with many important cognitive functions. An important research goal is to describe the mechanisms implemented by the neocortex. There is an apparent regularity in the structure of the neocortex [Brodmann 1909, Mountcastle 1957] which may help simplify this task. The work reported here addresses the problem of how to describe the putative repeated units ('cortical circuits') in a manner that is easily understood and manipulated, with the long-term goal of developing a mathematical and algorithmic description of their function. The approach is to reduce each algorithm to an enhanced perceptron-like structure and describe its computation using difference equations. We organize this algorithmic processing into larger structures based on physiological observations, and implement key modeling concepts in software which runs on parallel computing hardware.
Closed Circuit Videoinstallationen
DEFF Research Database (Denmark)
Kacunko, Slavko
be seen with only insignificant qualification as a specific characteristic of the medium. The closed-circuit video installations based on it represent the attest field of experiment for the assumptions on art and the theory and history of the medium that it might lead one make. In recent years......, theoretical debate on the medium has diagnosed with some precision where the electronic video image stands between analogue and digital codes, or again, between media representation and presentation; but that position has hardly ever been subjected to examination against the pertinent examples. An art...... of video as well as the latest digital art forms, can then be examined with the aid of such results and elucidated in historical terms. The prospect at least, of a gradual introduction of the electronic arts into the art history syllabus will be brought a deal closer thanks to such individual...
Diamond Integrated Optomechanical Circuits
Rath, Patrik; Nebel, Christoph; Wild, Christoph; Pernice, Wolfram H P
2013-01-01
Diamond offers unique material advantages for the realization of micro- and nanomechanical resonators due to its high Young's modulus, compatibility with harsh environments and superior thermal properties. At the same time, the wide electronic bandgap of 5.45eV makes diamond a suitable material for integrated optics because of broadband transparency and the absence of free-carrier absorption commonly encountered in silicon photonics. Here we take advantage of both to engineer full-scale optomechanical circuits in diamond thin films. We show that polycrystalline diamond films fabricated by chemical vapour deposition provide a convenient waferscale substrate for the realization of high quality nanophotonic devices. Using free-standing nanomechanical resonators embedded in on-chip Mach-Zehnder interferometers, we demonstrate efficient optomechanical transduction via gradient optical forces. Fabricated diamond resonators reproducibly show high mechanical quality factors up to 11,200. Our low cost, wideband, carri...
VLSI circuits implementing computational models of neocortical circuits.
Wijekoon, Jayawan H B; Dudek, Piotr
2012-09-15
This paper overviews the design and implementation of three neuromorphic integrated circuits developed for the COLAMN ("Novel Computing Architecture for Cognitive Systems based on the Laminar Microcircuitry of the Neocortex") project. The circuits are implemented in a standard 0.35 μm CMOS technology and include spiking and bursting neuron models, and synapses with short-term (facilitating/depressing) and long-term (STDP and dopamine-modulated STDP) dynamics. They enable execution of complex nonlinear models in accelerated-time, as compared with biology, and with low power consumption. The neural dynamics are implemented using analogue circuit techniques, with digital asynchronous event-based input and output. The circuits provide configurable hardware blocks that can be used to simulate a variety of neural networks. The paper presents experimental results obtained from the fabricated devices, and discusses the advantages and disadvantages of the analogue circuit approach to computational neural modelling. PMID:22342970
Selective serotonergic excitation of callosal projection neurons
Directory of Open Access Journals (Sweden)
Daniel eAvesar
2012-03-01
Full Text Available Serotonin (5-HT acting as a neurotransmitter in the cerebral cortex is critical for cognitive function, yet how 5-HT regulates information processing in cortical circuits is not well understood. We tested the serotonergic responsiveness of layer 5 pyramidal neurons (L5PNs of the mouse medial prefrontal cortex (mPFC, and found 3 distinct response types: long-lasting 5-HT1A (1A receptor-dependent inhibitory responses (84% of L5PNs, 5-HT2A (2A receptor-dependent excitatory responses (9%, and biphasic responses in which 2A-dependent excitation followed brief inhibition (5%. Relative to 5-HT-inhibited neurons, those excited by 5-HT had physiological properties characteristic of callosal/commissural (COM neurons that project to the contralateral cortex. We tested whether serotonergic responses in cortical pyramidal neurons are correlated with their axonal projection pattern using retrograde fluorescent labeling of COM and corticopontine-projecting (CPn neurons. 5-HT generated excitatory or biphasic responses in all 5-HT-responsive layer 5 COM neurons. Conversely, CPn neurons were universally inhibited by 5-HT. Serotonergic excitation of COM neurons was blocked by the 2A antagonist MDL 11939, while serotonergic inhibition of CPn neurons was blocked by the 1A antagonist WAY 100635, confirming a role for these two receptor subtypes in regulating pyramidal neuron activity. Selective serotonergic excitation of COM neurons was not layer-specific, as COM neurons in layer 2/3 were also selectively excited by 5-HT relative to their non-labeled pyramidal neuron neighbors. Because neocortical 2A receptors are implicated in the etiology and pathophysiology of schizophrenia, we propose that COM neurons may represent a novel cellular target for intervention in psychiatric disease.
Quantum memristor in a superconducting circuit
Salmilehto, Juha; Sanz, Mikel; di Ventra, Massimiliano; Solano, Enrique
Memristors, resistive elements that retain information of their past, have garnered interest due to their paradigm-changing potential in information processing and electronics. The emergent hysteretic behaviour allows for novel architectural applications and has recently been classically demonstrated in a simplified superconducting setup using the phase-dependent conductance in the tunnel-junction-microscopic model. In this contribution, we present a truly quantum model for a memristor constructed using established elements and techniques in superconducting nanoelectronics, and explore the parameters for feasible operation as well as refine the methods for quantifying the memory retention. In particular, the memristive behaviour is shown to arise from quasiparticle-induced tunneling in the full dissipative model and can be observed in the phase-driven tunneling current. The relevant hysteretic behaviour should be observable using current state-of-the-art measurements for detecting quasiparticle excitations. Our theoretical findings constitute the first quantum memristor in a superconducting circuit and act as the starting point for designing further circuit elements that have non-Markovian characteristics The authors acknowledge support from the CCQED EU project and the Finnish Cultural Foundation.
Institute of Scientific and Technical Information of China (English)
张宏喜
2011-01-01
The paper first introduced the commonly used starting methods of winding motor and its main shortcomings and then the principles and structural character, main performance and typical application effect of brushless automatic control soft starter are introduced. At last, the advantages of brushless motor automatic control soft starter are discussed and the necessity of replacing other types of motor starting device.%本文先简要介绍绕线电机常用的起动方法和存在的主要缺点,后介绍无刷自控电机软起动器的原理、结构特点、主要性能及典型应用效果,说明无刷自控电机软起动器的优势和代替其它电机起动装置的必然性.
Design and Study of Dual-Redundancy Brushless DC Motor for Actuator Servo System%舵机用双余度无刷直流电动机设计研究
Institute of Scientific and Technical Information of China (English)
高金行; 戴志勇; 全兴源; 艾于琛
2011-01-01
以舵机用双余度无刷直流电动机为研究对象,通过数学建模,对无刷直流电动机进行性能仿真,重点介绍样机被测波形及性能数据列表,分析余度换向性能的关键技术,以实现性能调试最优.%A study of dual redundant brushless DC motor for actuator servo system was given. With the mathematical model of brushless DC motor, the simulation performance was shown. The waveforms of BLDC motor were introduced. The performance data of motor was listed. The key technology of commutation was analyzed. The performance was made perfectly.
基于单片机的无刷直流电动机控制系统设计%Design of Brushless DC Motor Control System Based on MCU
Institute of Scientific and Technical Information of China (English)
闵次凡
2012-01-01
介绍了无刷直流电动机(BLDCM)的基本结构和工作原理.重点阐述了利用8751单片机控制无刷直流电动机的换相、调速、限制启动电流、正反转的原理和实现方法以及程序设计.%This paper introduces the basic structure and working principle of brushless DC motor (BLDCM). This paper expounds the principle and method to control the phase transformation, speed regulation, starting current limit, reverse rotation of brushless DC motor by single chip microcomputer 8751 , and the program design.
Pharmacokinetics and "RC" Circuit Concepts
De Cock, Mieke; Janssen, Paul
2013-01-01
Most introductory physics courses include a chapter on "RC" circuits in which the differential equations for the charging and discharging of a capacitor are derived. A number of papers in this journal describe lab experiments dealing with the measurement of different parameters in such "RC" circuits. In this contribution, we…
Enhancement of Linear Circuit Program
DEFF Research Database (Denmark)
Gaunholt, Hans; Dabu, Mihaela; Beldiman, Octavian
1996-01-01
In this report a preliminary user friendly interface has been added to the LCP2 program making it possible to describe an electronic circuit by actually drawing the circuit on the screen. Component values and other options and parameters can easily be set by the aid of the interface. The interface...
Logic Circuit Design Selected Methods
Vingron, Shimon P
2012-01-01
In three main divisions the book covers combinational circuits, latches, and asynchronous sequential circuits. Combinational circuits have no memorising ability, while sequential circuits have such an ability to various degrees. Latches are the simplest sequential circuits, ones with the shortest memory. The presentation is decidedly non-standard. The design of combinational circuits is discussed in an orthodox manner using normal forms and in an unorthodox manner using set-theoretical evaluation formulas relying heavily on Karnaugh maps. The latter approach allows for a new design technique called composition. Latches are covered very extensively. Their memory functions are expressed mathematically in a time-independent manner allowing the use of (normal, non-temporal) Boolean logic in their calculation. The theory of latches is then used as the basis for calculating asynchronous circuits. Asynchronous circuits are specified in a tree-representation, eac...
From strong to ultrastrong coupling in circuit QED architectures
International Nuclear Information System (INIS)
The field of cavity quantum electrodynamics (cavity QED) studies the interaction between light and matter on a fundamental level: a single atom interacts with a single photon. If the atom-photon coupling is larger than any dissipative effects, the system enters the strong-coupling limit. A peculiarity of this regime is the possibility to form coherent superpositions of light and matter excitations - a kind of 'molecule' consisting of an atomic and a photonic contribution. The novel research field of circuit QED extends cavity QED concepts to solid-state based system. Here, a superconducting quantum bit is coupled to an on-chip superconducting one-dimensional waveguide resonator. Owing to the small mode-volume of the resonant cavity, the large dipole moment of the 'artificial atom' and the enormous engineering potential inherent to superconducting quantum circuits, remarkable atom-photon coupling strengths can be realized. This thesis describes the theoretical framework, the development of fabrication techniques and the implementation of experimental characterization techniques for superconducting quantum circuits for circuit QED applications. In particular, we study the interaction between superconducting flux quantum bits and high-quality coplanar waveguide resonators in the strong-coupling limit. Furthermore, we report on the first experimental realization of a circuit QED system operating in the ultrastrong-coupling regime, where the atom-photon coupling rate reaches a considerable fraction of the relevant system frequencies. In these experiments we could observe phenomena that can not be explained within the renowned Jaynes-Cummings model. (orig.)
Design and construction of a nuclear magnetic resonator circuit
International Nuclear Information System (INIS)
It is described the operation of a feedback circuit that it using the nuclear resonance phenomena and that covers a broad sweeping interval in frequency with a minimum adjustment of the circuit elements and it produces an appropriate nuclear absorption for a sign relation at reasonable noise. The circuit is an oscillator amplifier modulated that it is based its sensibility and stability in an inductive-capacitive arrangement in parallel and always operate in resonant condition, in such a way that the quality factor of Q arrangement has been very elevated. Thus when the nuclear absorption occurs it is producing a fall of Q effective. The oscillation amplitude is controllable and it maintains in a convenient value over the operation interval using control by feedback. The circuit uses a configuration 'Auto dyne Hop kin' that it suffers as a follower of inductive charge, which have the main characteristic of to cause a negative resistance that it appears through the tuning circuit. It is introduced a control for feedback via two trajectories, the first by differential pair for to maintain the amplitude level in RF and the second for to stability a band wide interval in the modulation condition. It is necessary since the RF signal value must have a value to excite the specimen nucleus without to carry to saturate it and that the permanence in the absorption region was appropriate. Between applications of the nuclear magnetic resonance phenomena we have the magnetic fields measurements, physicochemical molecular properties studies, training and medical instrumentation. (Author)
49 CFR 236.728 - Circuit, trap.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, trap. 236.728 Section 236.728... Circuit, trap. A term applied to a circuit used where it is desirable to provide a track circuit but where it is impracticable to maintain a track circuit....
Variational integrators for electric circuits
Ober-Blöbaum, Sina; Cheng, Mulin; Owhadi, Houman; Marsden, Jerrold E
2011-01-01
In this contribution, we develop a variational integrator for the simulation of (stochastic and multiscale) electric circuits. When considering the dynamics of an electrical circuit, one is faced with three special situations: 1. The system involves external (control) forcing through external (controlled) voltage sources and resistors. 2. The system is constrained via the Kirchhoff current (KCL) and voltage laws (KVL). 3. The Lagrangian is degenerate. Based on a geometric setting, an appropriate variational formulation is presented to model the circuit from which the equations of motion are derived. A time-discrete variational formulation provides an iteration scheme for the simulation of the electric circuit. Dependent on the discretization, the intrinsic degeneracy of the system can be canceled for the discrete variational scheme. In this way, a variational integrator is constructed that gains several advantages compared to standard integration tools for circuits; in particular, a comparison to BDF methods ...
Electronic design with integrated circuits
Comer, D. J.
The book is concerned with the application of integrated circuits and presents the material actually needed by the system designer to do an effective job. The operational amplifier (op amp) is discussed, taking into account the electronic amplifier, the basic op amp, the practical op amp, analog applications, and digital applications. Digital components are considered along with combinational logic, digital subsystems, the microprocessor, special circuits, communications, and integrated circuit building blocks. Attention is given to logic gates, logic families, multivibrators, the digital computer, digital methods, communicating with a computer, computer organization, register and timing circuits for data transfer, arithmetic circuits, memories, the microprocessor chip, the control unit, communicating with the microprocessor, examples of microprocessor architecture, programming a microprocessor, the voltage-controlled oscillator, the phase-locked loop, analog-to-digital conversion, amplitude modulation, frequency modulation, pulse and digital transmission, the semiconductor diode, the bipolar transistor, and the field-effect transistor.
Demultiplexer circuit for neural stimulation
Wessendorf, Kurt O; Okandan, Murat; Pearson, Sean
2012-10-09
A demultiplexer circuit is disclosed which can be used with a conventional neural stimulator to extend the number of electrodes which can be activated. The demultiplexer circuit, which is formed on a semiconductor substrate containing a power supply that provides all the dc electrical power for operation of the circuit, includes digital latches that receive and store addressing information from the neural stimulator one bit at a time. This addressing information is used to program one or more 1:2.sup.N demultiplexers in the demultiplexer circuit which then route neural stimulation signals from the neural stimulator to an electrode array which is connected to the outputs of the 1:2.sup.N demultiplexer. The demultiplexer circuit allows the number of individual electrodes in the electrode array to be increased by a factor of 2.sup.N with N generally being in a range of 2-4.
Hardness and excitation energy
Indian Academy of Sciences (India)
Á Nagy
2005-09-01
The concept of the ensemble Kohn-Sham hardness is introduced. It is shown that the first excitation energy can be given by the Kohn-Sham hardness (i.e. the energy difference of the ground-state lowest unoccupied and highest occupied levels) plus an extra term coming from the partial derivative of the ensemble exchange-correlation energy with respect to the weighting factor in the limit → 0. It is proposed that the first excitation energy can be used as a reactivity index instead of the hardness.
Institute of Scientific and Technical Information of China (English)
夏鲲; 朱琳玲; 曾彦能; 徐鑫悦; 杨益华
2015-01-01
Focusing on popular existed high commutation torque ripple of square waves driving brushless DC motors, this paper presented a new method of suppressing commutation torque ripple for brushless DC motors based on a Quasi-Z-Source net. The Quasi-Z-Source net was employed at the front of the three-phase bridge. The control strategy was to adjust the DC link voltage of the motor controller via the Quasi-Z-Source net to keep the incoming and outgoing phase currents changing at the same rate during commutation, hence to effectively suppress commutation torque ripple. The cause of commutation ripple was analyzed. A novel circuit topology and a control algorithm of suppressing commutation torque ripple employed a Quasi-Z-Source net before the inverter was introduced in detail. Finally, simulation and experimental results show that, the proposed method can effectively minimizing commutation torque ripple. Torque ripple can be reduced to below 4.6% of the average torque by using appropriate circuit parameters in a simulation mode. And torque ripple can also be reduced to below 12% of the average torque via experimentation in real situation.%针对方波驱动的无刷直流电机普遍存在的换相转矩脉动较大的问题，提出了一种基于准 Z 源网络抑制永磁无刷直流电机换相转矩脉动的方法。在三相桥臂前级增加准 Z源网络，换相期间由准 Z 源网络调整直流母线电压，使电机关断相电流下降速率与开通相电流上升速率相等，从而有效抑制换相转矩脉动。分析了换相转矩脉动产生的原因，详细介绍了通过增加前级功率变换电路抑制换相转矩脉动的电路拓扑与控制算法。仿真及实验结果表明，该方法能够有效抑制永磁无刷直流电机换相转矩脉动，如采用合适的电路参数，仿真模型中转矩脉动可减少到平均转矩的4.6%以下，实际设计的系统实验可将转矩脉动抑制在平均转矩的12%以下。
Institute of Scientific and Technical Information of China (English)
王法龙; 郑明辉
2015-01-01
针对常规PI在无刷电机调速中控制精度低及动态性能差，无法满足裁断机对动力辊电机速度控制要求，本文提出了一种自适应模糊PI控制方法。该方法应用于无刷直流电机双闭环控制的速度外环控制，提高了无刷直流电机的控制精度和动态响应性能。通过Matlab进行仿真，仿真结果表明，采用自适应模糊PI控制相对常规PI控制，无刷直流电机的调速系统具有很好的动态和静态性能，快速响应，超调量小，抗干扰能力强，鲁棒性好。%In the conventional PI control of brushless motor speed low precision and dynamic performance is poor, unable to meet the power roller cutting machine for motor speed control requirements, we propose an adaptive fuzzy PI control method. The method is applied to double-loop control of brushless DC motor speed outer control, improved control accuracy and dynamic response performance brushless DC motor. Through Matlab simulation results show that the adaptive fuzzy PI speed control system to control relative to conventional PI control, brushless DC motor has a good dynamic and static performance, fast response, small overshoot, and strong anti-jamming capability, robustness.
Study on the Reliability of the Brushless PM Motor Based on Bayes Theory%基于Bayes理论的永磁无刷电机的可靠性研究
Institute of Scientific and Technical Information of China (English)
何银光; 胡小东; 常荣胜
2012-01-01
为了能够提高永磁无刷电机的可靠性评估水平,利用Bayes理论对其进行了可靠性评估.文中首先给出了Bayes理论的基本概念,然后建立了Weibull分布下永磁无刷电机的Bayes理论模型；最后,基于上述模型设计了永磁无刷电机的可靠性试验,根据截尾试验获得的可靠性数据对永磁无刷电机可靠性参数进行了估计.分析结果表明利用Bayes理论采用较少的样本就能获得充分的可靠度的参数估计值,具有较好的前瞻性.%In order to improve the reliability evaluation level of the brushless PM motor, and the Bayes theory is applied to have reliability evaluation of it. First, the basic conceptions of the Bayes theory is analyzed, and then the Bayes theory model of the brushless PM motor of WeibuII distribution is studied, and finally the reliability test of the brushless PM motor is designed, and the reliable pnrnmrtcr of the brushless PM notor is evaluated according to the reliable data obtained from the censored lifetime data test, and results show that this method can get the adequate parameter evaluation value of reliability, this method has better estimation character.
Control System of Two-Phase Brushless DC Gyro Motor Based on DSP%基于DSP的两相无刷直流陀螺电机稳速系统
Institute of Scientific and Technical Information of China (English)
吴梅锡; 付鲁华; 林玉池
2013-01-01
The research of the influence of gyro motor speed stability on the north-finding result is studied in order to improve the gyro north-finding precision. The paper introduces a two-phase brushless DC gyro motor control system based on TMS320LF2407A. First,it expounds the two-phase brushless DC motor's working principle. Then through the design of the hardware and software system, the close-loop control of two-phase brushless DC gyro motor is realized. The experimental results show that,the system can drive the brushless DC gyro motor well starting,braking and smooth running. The precision of the steady speed is less than 10~6 and the characteristics of the system satisfy the gyroscope demand.%为了进一步提高陀螺仪的寻北精度,分析研究了陀螺电机转速大小和转速精度对寻北结果的影响.在此基础上设计了一种基于TMS320LF2407A的两相无刷直流陀螺电机控制系统,阐述了两相无刷直流电机的工作原理,给出了电机的简化结构及数学模型,并通过对硬件系统和软件算法的设计实现了两相无刷直流陀螺电机的闭环控制.实验结果表明:系统可以很好地完成电机的启动、制动和平稳运行,转速精度优于10-6,满足陀螺仪的工作要求.
Excitation Methods for Bridge Structures
Energy Technology Data Exchange (ETDEWEB)
Farrar, C.R.; Duffy, T.A.; Cornwell, P.J.; Doebling, S.W.
1999-02-08
This paper summarizes the various methods that have been used to excited bridge structures during dynamic testing. The excitation methods fall into the general categories of ambient excitation methods and measured-input excitation methods. During ambient excitation the input to the bridge is not directly measured. In contrast, as the category label implies, measured-input excitations are usually applied at a single location where the force input to the structure can be monitored. Issues associated with using these various types of measurements are discussed along with a general description of the various excitation methods.
Institute of Scientific and Technical Information of China (English)
杨闯; 王国辉
2014-01-01
结合永磁无刷直流电机设计和应用，以Φ300 mm、DC36 V打草机为例，从电池包空载放电时间、切割效率、单电池包工作时间、抗过载性及结构优化设计等五个方面分析永磁无刷直流电机与永磁有刷直流电机的区别，得出永磁无刷直流电机性能占优的结论。%Take the Φ300 mm DC36V grass trimmer for example, combined with the design and application of permanent magnet brushless DC motor, the author analyzes the difference between permanent magnet brushless DC motor and permanent magnet brush DC motor from five aspects such as battery pack discharge time, cutting efficiency, single battery pack working time, anti-overload resistance and structural optimization design, and comes to the conclusion that permanent magnet brushless DC motor superiors.
The Research on Simulation Model of DTC with Brushless DC motor%无刷直流电机直接转矩控制系统仿真研究
Institute of Scientific and Technical Information of China (English)
宫殿强
2012-01-01
In this paper, the basic structure of the brushless DC motor starting, contacting the Direct Torque Control, it deduced improved brushless DC motor direct torque control system. The improved brushless DC motor direct torque control system's software model based full analysis of direct torque control principles and components, was presented by means of Matlab / Simulink software. The simulation results showed that the improved direct torque control had favourable dynamics and statics.%从无刷直流电机的基本结构出发,联系直接转矩控制理论,提出了改进型无刷直流电机直接转矩控制系统,在对系统的基本原理和组成部分进行充分分析的基础上,利用Matlab/Simulink建立了无刷直流电机直接转矩控制系统的软件模型.仿真结果表明改进型直接转矩控制系统具有良好的动静态性能.
Design of Portable Garden Mowers Based on a Brushless Motor Control System%基于无刷电机控制系统的便携式园林割草机设计
Institute of Scientific and Technical Information of China (English)
段亚东
2012-01-01
Based on a thorough study of China＇s mower technologies,a simple and practical portable garden mower is designed.The mower uses a brushless motor and its technical performance parameters have improved substantially,compared with traditional brush motors.The mower uses the drive chip IR2130 dedicated for brushless DC motors as its control chip and uses power device MOSFET as its switch to realize the control of brushless DC motors.%在深入研究我国割草机技术的基础上,设计了简单实用的园林便携式割草机。该割草机采用无刷电动机,与传统有刷电动机相比,其主要技术性能大幅提升。以无刷直流电动机专用驱动芯片IR2130为控制芯片,以功率器件MOSFET为开关器件,可实现对无刷直流电动机的控制。
基于DSP的无刷直流电动机控制系统的研究与设计%Research and Design of Brushless DC Motor Control System Based on DSP
Institute of Scientific and Technical Information of China (English)
王宪磊; 王淑红
2012-01-01
介绍了无刷直流电动机的基本结构、工作原理和运行特性，简述了基于DSP的无刷直流电动机的控制策略，对无刷直流电动机双闭环控制系统的硬、软件设计作了详细论述。文章所述无刷直流电动机控制系统的设计方案，可以获得良好的速度控制性能。% The basic structure, working principle and operation characteristics of brushless DC motor were introduced. The control strategy of brushless DC motor based on DSP was expounded, and the hardware and software design of the double closed loop control system was expounded in detail. The brushless DC motor control system described in this paper show good performance in speed control.
一种抑制无刷直流电机转矩脉动的新方法%A Method to Suppress Torque Ripple of Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
谢少华; 瞿遂春
2015-01-01
对无刷直流电机转矩脉动产生的原因进行全面分析，提出增加前级直流变换器抑制转矩脉动的新方法，使用buck直流变换器，通过调整逆变器的母线电压来抑制转矩脉动，在MATLAB/Simulink环境下基于该方法搭建无刷直流电机仿真模型，并对系统进行仿真分析。仿真结果表明，该方法能够有效抑制无刷直流电机转矩脉动。%Analyzes comprehensively the torque ripple causes of brushless DC motor, and proposes a new method of adding the first stage DC converter to control torque ripple. By using buck DC converter and adjusting bus voltage of the inverter to suppress the torque ripple, on the basis establishes brushless DC motor model in MATLAB/Simulink and simulates the system. The result indicates that the method suppresses the torque ripple of brushless DC motor effectively.
Dual channel nitrogen laser useful for nanosecond excited state studies
International Nuclear Information System (INIS)
Shipman (1967) adapted the Blumlein discharge circuit to lasers and this method has proved highly useful in producing high peak pulses. The authors describe a double Blumlein producing two 250 kW pulses separated by 15 nanosecs. The dual channel nitrogen laser is designed for use in atomic spectroscopy, the first pulse excites the target atoms while the second pumps another laser whose output is used to study the levels. (U.S.)
Parcell, L. A.; Mceachran, R. P.; Stauffer, A. D.
1990-01-01
The differential and total cross section for the excitation of the 3s1P10 and 3p1P1 states of neon by positron impact were calculated using a distorted-wave approximation. The results agree well with experimental conclusions.
Decoherence at constant excitation
Torres, J. M.; Sadurní, E.; Seligman, T. H.
2012-02-01
We present a simple exactly solvable extension of the Jaynes-Cummings model by adding dissipation. This is done such that the total number of excitations is conserved. The Liouville operator in the resulting master equation can be reduced to blocks of 4×4 matrices.
Decoherence at constant excitation
Torres, Juan Mauricio; Seligman, Thomas H
2011-01-01
We present a simple exactly solvable extension of of the Jaynes-Cummings model by adding dissipation. This is done such that the total number of excitations is conserved. The Liouville operator in the resulting master equation can be reduced to blocks of $4\\times 4$ matrices.
International Nuclear Information System (INIS)
Using the CELLO detector at PETRA we have searched for excited leptons by studying e+e- interactions which yield rho+rho-γγ, rho+rho-γ and γγ final states, where l=e, μ or tau. We observe good agreement with QED and set new limits on e*, μ* and tau* production
Spine pruning drives antipsychotic-sensitive locomotion via circuit control of striatal dopamine.
Kim, Il Hwan; Rossi, Mark A; Aryal, Dipendra K; Racz, Bence; Kim, Namsoo; Uezu, Akiyoshi; Wang, Fan; Wetsel, William C; Weinberg, Richard J; Yin, Henry; Soderling, Scott H
2015-06-01
Psychiatric and neurodevelopmental disorders may arise from anomalies in long-range neuronal connectivity downstream of pathologies in dendritic spines. However, the mechanisms that may link spine pathology to circuit abnormalities relevant to atypical behavior remain unknown. Using a mouse model to conditionally disrupt a critical regulator of the dendritic spine cytoskeleton, the actin-related protein 2/3 complex (Arp2/3), we report here a molecular mechanism that unexpectedly reveals the inter-relationship of progressive spine pruning, elevated frontal cortical excitation of pyramidal neurons and striatal hyperdopaminergia in a cortical-to-midbrain circuit abnormality. The main symptomatic manifestations of this circuit abnormality are psychomotor agitation and stereotypical behaviors, which are relieved by antipsychotics. Moreover, this antipsychotic-responsive locomotion can be mimicked in wild-type mice by optogenetic activation of this circuit. Collectively these results reveal molecular and neural-circuit mechanisms, illustrating how diverse pathologies may converge to drive behaviors relevant to psychiatric disorders.
Performance analysis of electrical circuits /PANE/
Johnson, K. L.; Steinberg, L. L.
1968-01-01
Automated statistical and worst case computer program has been designed to perform dc and ac steady circuit analyses. The program determines the worst case circuit performance by solving circuit equations.
30 CFR 75.800 - High-voltage circuits; circuit breakers.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. High-voltage circuits entering the underground area of any coal mine shall be protected by suitable circuit breakers of adequate interrupting...
International Nuclear Information System (INIS)
The minimum and maximum excitation capacitance required for a self excited single phase induction generator using a three phase machine has been determined by an eigenvalue and eigenvalue sensitivity approach. It is observed that the required minimum capacitance reduces with the increase in load. Traditionally, the minimum and maximum capacitances required for a self excited induction generator (SEIG) were solved by a high order non-linear polynomial equation based on a per phase equivalent circuit model. The advantage of this proposed method is its simplicity since the complicated solution procedure of the high order polynomial is avoided. The generator consists of a three phase star connected induction machine with three capacitors connected in series and parallel with a single phase load. The developed dynamic model of the SEIG is based on the stationary reference frame d-q axes theory, and the equations of the excitation capacitors are described by a three phase abc model assuming a constant speed prime mover. The capacitance values obtained by the proposed method have been compared with those obtained by the conventional method and verified experimentally to confirm the validity and the accuracy of the proposed method
Global optimization of digital circuits
Flandera, Richard
1991-12-01
This thesis was divided into two tasks. The first task involved developing a parser which could translate a behavioral specification in Very High-Speed Integrated Circuits (VHSIC) Hardware Description Language (VHDL) into the format used by an existing digital circuit optimization tool, Boolean Reasoning In Scheme (BORIS). Since this tool is written in Scheme, a dialect of Lisp, the parser was also written in Scheme. The parser was implemented is Artez's modification of Earley's Algorithm. Additionally, a VHDL tokenizer was implemented in Scheme and a portion of the VHDL grammar was converted into the format which the parser uses. The second task was the incorporation of intermediate functions into BORIS. The existing BORIS contains a recursive optimization system that optimizes digital circuits by using circuit outputs as inputs into other circuits. Intermediate functions provide a greater selection of functions to be used as circuits inputs. Using both intermediate functions and output functions, the costs of the circuits in the test set were reduced by 43 percent. This is a 10 percent reduction when compared to the existing recursive optimization system. Incorporating intermediate functions into BORIS required the development of an intermediate-function generator and a set of control methods to keep the computation time from increasing exponentially.
Spectral Purity Enhancement via Polyphase Multipath Circuits
Mensink, Eisse; Klumperink, Eric; Nauta, Bram
2004-01-01
The central question of this paper is: can we enhance the spectral purity of nonlinear circuits by using polyphase multipath circuits? The basic idea behind polyphase multipath circuits is to split the nonlinear circuits into two or more paths and exploit phase differences between these paths to cancel undesired distortion products. It turns out that it is very well possible to use polyphase multipath circuits to cancel distortion products produced by a nonlinear circuit. Unfortunately, there...
Determining Covers in Combinational Circuits
Directory of Open Access Journals (Sweden)
Ljubomir Cvetkovic
2011-05-01
Full Text Available In this paper we propose a procedure for determining 0- or 1-cover of an arbitrary line in a combinational circuit. When determining a cover we do not need Boolean expression for the line; only the circuit structure is used. Within the proposed procedure we use the tools of the cube theory, in particular, some operations defined on cubes. The procedure can be applied for determining 0- and 1- covers of output lines in programmable logic devices. Basically, this procedure is a method for the analysis of a combinational circuit.
The Maplin electronic circuits handbook
Tooley, Michael
2015-01-01
The Maplin Electronic Circuits Handbook provides pertinent data, formula, explanation, practical guidance, theory and practical guidance in the design, testing, and construction of electronic circuits. This book discusses the developments in electronics technology techniques.Organized into 11 chapters, this book begins with an overview of the common types of passive component. This text then provides the reader with sufficient information to make a correct selection of passive components for use in the circuits. Other chapters consider the various types of the most commonly used semiconductor
Secure integrated circuits and systems
Verbauwhede, Ingrid MR
2010-01-01
On any advanced integrated circuit or 'system-on-chip' there is a need for security. In many applications the actual implementation has become the weakest link in security rather than the algorithms or protocols. The purpose of the book is to give the integrated circuits and systems designer an insight into the basics of security and cryptography from the implementation point of view. As a designer of integrated circuits and systems it is important to know both the state-of-the-art attacks as well as the countermeasures. Optimizing for security is different from optimizations for speed, area,
Adult neurogenesis modifies excitability of the dentate gyrus
Directory of Open Access Journals (Sweden)
Taruna eIkrar
2013-12-01
Full Text Available Adult-born dentate granule neurons contribute to memory encoding functions of the dentate gyrus (DG such as pattern separation. However, local circuit-mechanisms by which adult-born neurons partake in this process are poorly understood. Computational, neuroanatomical and electrophysiological studies suggest that sparseness of activation in the granule cell layer (GCL is conducive for pattern separation. A sparse coding scheme is thought to facilitate the distribution of similar entorhinal inputs across the GCL to decorrelate overlapping representations and minimize interference. Here we used fast voltage-sensitive dye (VSD imaging combined with laser photostimulation and electrical stimulation to examine how selectively increasing adult DG neurogenesis influences local circuit activity and excitability. We show that DG of mice with more adult-born neurons exhibits decreased strength of neuronal activation and more restricted excitation spread in GCL while maintaining effective output to CA3c. Conversely, blockade of adult hippocampal neurogenesis changed excitability of the DG in the opposite direction. Analysis of GABAergic inhibition onto mature dentate granule neurons in the DG of mice with more adult-born neurons shows a modest readjustment of perisomatic inhibitory synaptic gain without changes in overall inhibitory tone, presynaptic properties or GABAergic innervation pattern. Retroviral labeling of connectivity in mice with more adult-born neurons showed increased number of excitatory synaptic contacts of adult-born neurons onto hilar interneurons. Together, these studies demonstrate that adult hippocampal neurogenesis modifies excitability of mature dentate granule neurons and that this non-cell autonomous effect may be mediated by local circuit mechanisms such as excitatory drive onto hilar interneurons. Modulation of DG excitability by adult-born dentate granule neurons may enhance sparse coding in the GCL to influence pattern
Analyzing a Vibrating Wire Transducer using Coupled Resonator Circuits
Directory of Open Access Journals (Sweden)
POP, S.
2015-08-01
Full Text Available This paper intends to be an approach on the vibrating wire transducer from the perspective of the necessary rules used for a correct measurement procedure. There are several studies which analyze the vibrating wire transducer as a mechanical system. However, a comparative time-domain analysis between the mechanical and the electrical model is lacking. The transducer analysis is based on a theoretical analysis of the equivalent circuit, on both excitation and response time intervals. The electrical model consists of two magnetic coupled resonating circuits. When connected to an excitation source, there will be an energy transfer from the coil to the wire. The maximum energy transfer will occur at the vibrating wire's frequency of resonance. Using the transient regime analysis, it has been proven that, in the response time interval - when the wire vibrates freely, the current through the circuit that models the wire describes the oscillating movement of the wire. A complex signal is obtained, that contains both coil's and wire's frequencies of resonance, strongly dependent with theirs parasitic elements. The mathematical analysis highlights the similarity between mechanical and electrical model and the procedures in order to determine the wire frequency of resonance from the output signal.
CADAT integrated circuit mask analysis
1981-01-01
CADAT System Mask Analysis Program (MAPS2) is automated software tool for analyzing integrated-circuit mask design. Included in MAPS2 functions are artwork verification, device identification, nodal analysis, capacitance calculation, and logic equation generation.
Discharge quenching circuit for counters
International Nuclear Information System (INIS)
A circuit for quenching discharges in gas-discharge detectors with working voltage of 3-5 kV based on transistors operating in the avalanche mode is described. The quenching circuit consists of a coordinating emitter follower, amplifier-shaper for avalanche key cascade control which changes potential on the counter electrodes and a shaper of discharge quenching duration. The emitter follower is assembled according to a widely used flowsheet with two transistors. The circuit permits to obtain a rectangular quenching pulse with front of 100 ns and an amplitude of up to 3.2 kV at duration of 500 μm-8 ms. Application of the quenching circuit described permits to obtain countering characteristics with the slope less than or equal to 0.02%/V and plateau extent greater than or equal to 300 V
Wireless communications circuits and systems
Sun, Yichuang
2004-01-01
This new book examines integrated circuits, systems and transceivers for wireless and mobile communications. It covers the most recent developments in key RF, IF, analogue, mixed-signal components and single-chip transceivers in CMOS technology.
Extensional Uniformity for Boolean Circuits
McKenzie, Pierre; Vollmer, Heribert
2008-01-01
Imposing an extensional uniformity condition on a non-uniform circuit complexity class C means simply intersecting C with a uniform class L. By contrast, the usual intensional uniformity conditions require that a resource-bounded machine be able to exhibit the circuits in the circuit family defining C. We say that (C,L) has the "Uniformity Duality Property" if the extensionally uniform class C \\cap L can be captured intensionally by means of adding so-called "L-numerical predicates" to the first-order descriptive complexity apparatus describing the connection language of the circuit family defining C. This paper exhibits positive instances and negative instances of the Uniformity Duality Property.
Circuit design on plastic foils
Raiteri, Daniele; Roermund, Arthur H M
2015-01-01
This book illustrates a variety of circuit designs on plastic foils and provides all the information needed to undertake successful designs in large-area electronics. The authors demonstrate architectural, circuit, layout, and device solutions and explain the reasons and the creative process behind each. Readers will learn how to keep under control large-area technologies and achieve robust, reliable circuit designs that can face the challenges imposed by low-cost low-temperature high-throughput manufacturing. • Discusses implications of problems associated with large-area electronics and compares them to standard silicon; • Provides the basis for understanding physics and modeling of disordered material; • Includes guidelines to quickly setup the basic CAD tools enabling efficient and reliable designs; • Illustrates practical solutions to cope with hard/soft faults, variability, mismatch, aging and bias stress at architecture, circuit, layout, and device levels.
Institute of Scientific and Technical Information of China (English)
韩力; 王华; 马南平; 刘航航
2012-01-01
Aiming at abundant harmonics and large harmonic losses of brushless doubly-fed machine (BD-FM) , the loss calculation models of BDFM were presented by considering the influence of harmonic magnetic field, harmonic currents, skin effect and rotating magnetization. Based on 2D time-stepping finite element model coupled with the circuit and the harmonic analysis method, two different models of rotor copper loss calculation and three different models of stator and rotor iron losses calculation were established , and the influence of different models on the rotor copper loss and the stator and rotor iron losses were analyzed. The variation tendency of BDFM harmonic copper and iron losses were then obtained. The results show that the model 2 of rotor copper loss and the model 3 of stator and rotor iron losses are more accurate. With the increase of control winding voltage of BDFM, the stator and rotor copper losses decrease first and then increase, the stator and rotor iron losses increase constantly. With the increase of BDFM load torque, the copper and iron losses both on stator and rotor increase continually. By comparison of the calculated results of copper and iron losses with the electromagnetic design data and the test data of a similar asynchronous machine, the correctness of the presented models and the calculated results are verified.%针对无刷双馈电机谐波含量高、谐波损耗大的问题,提出考虑谐波磁场、谐波电流、集肤效应和旋转磁化影响的BDFM损耗计算模型.基于二维场路耦合时步有限元模型和谐波分析方法,分别建立两种转子铜耗计算模型和三种定转子铁耗计算模型,分析不同计算模型对转子铜耗和定转子铁耗的影响,得到定转子谐波铜耗和铁耗的变化规律.结果表明,转子铜耗模型2以及定转子铁耗模型3更精确；随着控制绕组电压的增加,定转子铜耗先减小后增加,定转子铁耗持续增加；随着负载转矩的增加,定转
International Nuclear Information System (INIS)
Experimental indications leading to the thought of a very excited nucleus fragmentation are resumed. Theoretical approaches are briefly described; they are used to explain the phenomenon in showing off they are based on a minimum information principle. This model is based on time dependent Thomas-Fermi calculation which allows the mean field effect description, and with a site-bound percolation model which allows the fluctuation description
Cytokines and brain excitability
Galic, Michael A.; Riazi, Kiarash; Pittman, Quentin J.
2011-01-01
Cytokines are molecules secreted by peripheral immune cells, microglia, astrocytes and neurons in the central nervous system. Peripheral or central inflammation is characterized by an upregulation of cytokines and their receptors in the brain. Emerging evidence indicates that pro-inflammatory cytokines modulate brain excitability. Findings from both the clinical literature and from in vivo and in vitro laboratory studies suggest that cytokines can increase seizure susceptibility and may be in...
PWM调制下无刷直流电机的转矩脉动抑制%Torque Ripple Reduction of Brushless DC Motors by PWM Modes
Institute of Scientific and Technical Information of China (English)
孟光伟; 李槐树; 熊浩
2011-01-01
分析无刷直流电机在PWM调制下稳态时的换相过程,通过在换相期间的PWM调制来实现高、低速条件下的换相转矩脉动补偿控制,确定了保持换相期间非换相相电流幅值不变的换相时间.分析PWM调制方式对三相六状态二二导通无刷直流电机控制系统的影响,提出了在PWM-ON-PWM调制方式下的换相转矩脉动补偿控制,不但能够完全消除非换相期间由于关断相出现电流而引起的电磁转矩脉动,而且能够完全补偿由于换相而引起的转矩脉动,实现电机在低速和高速时的无转矩脉动控制.%The steady commutation process of brushless DC motor by PWM modes was analyzed, and realized phase conversion torque ripple compensation control under both low speed and high speed operation by PWM control in commutation period,and confirmed commutation time to hold amplitude of current in commutation period. The effect by PWM modes on a three-phase six-state 120°conduction brushless DC motor was analyzed,and proposed torque ripple compensation control in PWM_ON_PWM mode, which can not only entirely eliminate torque ripple resulted from the current emerging in the turn-off phase during non-commutation period but also compensate torque ripple caused by the commutation current during commutation period. The torque ripple can be effectively reduced under both low speed and high speed operation using torque ripple compensation control in PWM ON PWM mode.
无刷直流电动机转子退磁故障的检测方法%Detection of rotor demagnetization fault on brushless DC motor
Institute of Scientific and Technical Information of China (English)
赵向阳; 葛文韬
2012-01-01
In order to study the demagnetization fault on brushless DC motor, the electro - motive - force (EMF) is resolved and the demagnetization fault is implemented based on the finite element method (FEA) with Ansoft/Maxwell. The system of brushless DC motor (BLDC) was simulated with Ansoft/ Simplorer software according to the mathematical model. In steady state, the fast Fourier transform (FFT) analysis was used on the stator current. The simulated model of detecting demagnetization based on the stator current signature analysis stator current signature analysis method was investigated and implemented ; the frequency used to indentify demagnetization fault, and the amplitude of frequency to estimate the demagnetization severity. In addition, the estimation of torque constant was used to detect the demagnetization fault. The results indicate that the stator current signature analysis can be used to detect the demagnetization fault when the speed pulsation is low and the estimation of torque constant method can be used to detect the demagnetization fault when the speed pulsation is high.%为了研究无刷直流电动机的转子退故障,基于Ansoft/Maxwell软件平台,设置转子退磁故障,建立求解电机反电动势的有限元模型；基于Ansoft/Simplorer软件平台,建立无刷直流电动机系统的仿真模型.在电机稳态运行下,对定子电流进行傅里叶分析,研究并建立基于定子电流监测转子退磁故障的仿真模型:退磁故障与特征频率的关系、退磁故障程度与特征频率幅值的关系.进一步,采用基于转矩常数估计的方法对无刷直流电机的转子退磁故障进行监测.仿真结果表明,在转速波动较小时采用定子电流分析法的效果更好,在转速波动较大时,采用转矩常数估计法可以在线监测无刷直流电动机转子的退磁故障.
The analysis of an operating mode of the asynchronous generator with capacitor excitation
Directory of Open Access Journals (Sweden)
Postoronca S.
2008-08-01
Full Text Available On the basis of a symbolical method of calculation of electric circuits the analysis of features of work of the three-phase asynchronous generator with two windings on статоре and capacitor excitation is executed. Results of the analysis of influence on a phase corner of a current and voltage of a windings of excitation of the generator are submitted at change of its loading from a mode of idling up to a mode of short circuit. Recommendations on stabilization of a target voltage of the generator are formulated at change of its loading.
Practical circuits with Physarum Wires
Whiting, James G. H.; Mayne, Richard; Moody, Nadine; Costello, Ben de Lacy; Adamatzky, Andrew
2015-01-01
Purpose: Protoplasmic tubes of Physarum polycephalum, also know as Physarum Wires (PW), have been previously suggested as novel bio- electronic components. Until recently, practical examples of electronic circuits using PWs have been limited. These PWs have been shown to be self repairing, offering significant advantage over traditional electronic components. This article documents work performed to produce practical circuits using PWs. Method: We have demonstrated through manufacture and tes...
Harmonically excited orbital variations
International Nuclear Information System (INIS)
Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs
Steady-state time-periodic finite element analysis of a brushless DC motor drive considering motion
Directory of Open Access Journals (Sweden)
Jagieła Mariusz
2015-09-01
Full Text Available This paper aims at providing a framework for comprehensive steady-state time-domain analysis of rotating machines considering motion. The steady-state waveforms of electromagnetic and circuit quantities are computed via iterative solution of the nonlinear field-circuit-and-motion problem with constraints of time periodicity. The cases with forced speed and forced load torque are considered. A comparison of execution times with a conventional time-stepping transient model is carried out for two different machines. The numerical stability of a time-periodic model with forced speed is shown to be worse than that of traditional transient time-stepping one, although the model converges within a reasonable number of iterations. This is not the case if forced load via equation of mechanical balance is accounted for. To ensure convergence of the iterative process the physical equation of motion is replaced by the fixed-point equation. In this way the model delivers time-periodic solutions regarding not only the electromagnetic quantities but also the rotational speed.
Receiver Gain Modulation Circuit
Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen
2011-01-01
A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by
Posture-related modulation of cortical excitability in the tibialis anterior muscle in humans.
Obata, Hiroki; Sekiguchi, Hirofumi; Ohtsuki, Tatsuyuki; Nakazawa, Kimitaka
2014-08-19
Corticospinal excitability in the lower leg muscles is enhanced during standing as compared to other postures. In the present study, we investigated how the excitability of intracortical circuits that control the tibialis anterior muscle (TA) is modulated during standing. Short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) were assessed by the paired-pulse transcranial magnetic stimulation technique during standing (STD) and sitting (SIT) with a comparable background activity level in both the soleus and the TA muscle. The results demonstrated that SICI was less effective during STD than during SIT, whereas ICF was more effective during STD than during SIT. These findings suggest that the excitabilities of these cortical neural circuits are modulated depending on posture. A decrease in SICI and an increase in ICF may reflect subliminal enhancement of the cortical excitability in the TA muscle during standing as compared with that during sitting. PMID:24978603
Electromagnetic Flow Meter Having a Driver Circuit Including a Current Transducer
Karon, David M. (Inventor); Cushing, Vincent (Inventor); Patel, Sandeep K. (Inventor)
2014-01-01
An electromagnetic flow meter (EMFM) accurately measures both the complete flow rate and the dynamically fluctuating flow rate of a fluid by applying a unipolar DC voltage to excitation coils for a predetermined period of time, measuring the electric potential at a pair of electrodes, determining a complete flow rate and independently measuring the dynamic flow rate during the "on" cycle of the DC excitation, and correcting the measurements for errors resulting from galvanic drift and other effects on the electric potential. The EMFM can also correct for effects from the excitation circuit induced during operation of the EMFM.
Two-dimensional lattice gauge theories with superconducting quantum circuits
Energy Technology Data Exchange (ETDEWEB)
Marcos, D., E-mail: david.marcos@me.com [Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck (Austria); Widmer, P. [Albert Einstein Center, Institute for Theoretical Physics, Bern University, CH-3012, Bern (Switzerland); Rico, E. [IPCMS (UMR 7504) and ISIS (UMR 7006), University of Strasbourg and CNRS, 67000 Strasbourg (France); Hafezi, M. [Joint Quantum Institute, NIST/University of Maryland, College Park 20742 (United States); Department of Electrical Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Rabl, P. [Institute of Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Wien (Austria); Wiese, U.-J. [Albert Einstein Center, Institute for Theoretical Physics, Bern University, CH-3012, Bern (Switzerland); Zoller, P. [Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck (Austria); Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck (Austria)
2014-12-15
A quantum simulator of U(1) lattice gauge theories can be implemented with superconducting circuits. This allows the investigation of confined and deconfined phases in quantum link models, and of valence bond solid and spin liquid phases in quantum dimer models. Fractionalized confining strings and the real-time dynamics of quantum phase transitions are accessible as well. Here we show how state-of-the-art superconducting technology allows us to simulate these phenomena in relatively small circuit lattices. By exploiting the strong non-linear couplings between quantized excitations emerging when superconducting qubits are coupled, we show how to engineer gauge invariant Hamiltonians, including ring-exchange and four-body Ising interactions. We demonstrate that, despite decoherence and disorder effects, minimal circuit instances allow us to investigate properties such as the dynamics of electric flux strings, signaling confinement in gauge invariant field theories. The experimental realization of these models in larger superconducting circuits could address open questions beyond current computational capability.
Difference-Equation/Flow-Graph Circuit Analysis
Mcvey, I. M.
1988-01-01
Numerical technique enables rapid, approximate analyses of electronic circuits containing linear and nonlinear elements. Practiced in variety of computer languages on large and small computers; for circuits simple enough, programmable hand calculators used. Although some combinations of circuit elements make numerical solutions diverge, enables quick identification of divergence and correction of circuit models to make solutions converge.
Multi-Layer E-Textile Circuits
Dunne, Lucy E.; Bibeau, Kaila; Mulligan, Lucie; Frith, Ashton; Simon, Cory
2012-01-01
Stitched e-textile circuits facilitate wearable, flexible, comfortable wearable technology. However, while stitched methods of e-textile circuits are common, multi-layer circuit creation remains a challenge. Here, we present methods of stitched multi-layer circuit creation using accessible tools and techniques.
Tunable circuit for tunable capacitor devices
Rivkina, Tatiana; Ginley, David S.
2006-09-19
A tunable circuit (10) for a capacitively tunable capacitor device (12) is provided. The tunable circuit (10) comprises a tunable circuit element (14) and a non-tunable dielectric element (16) coupled to the tunable circuit element (16). A tunable capacitor device (12) and a method for increasing the figure of merit in a tunable capacitor device (12) are also provided.
Experimental study of jittering chimeras in a ring of excitable units
Klinshov, Vladimir; Shchapin, Dmitry; Lücken, Leonhard; Yanchuk, Serhiy; Nekorkin, Vladimir
2016-06-01
A new type of chimera-like regime is reported that we call "jittering chimera". The regime is observed in a ring of excitable units in which the excitation is invoked by an oscillator included into the ring. The jittering chimera is characterized by the presence of two domains, one with regular spiking and the other with irregular. A method to set and control desired chimera states in a physically implemented electronic circuit is developed.
Passivity-Based Nonlinear Excitation Control of Power Systems with Structure Matrix Reassignment
Bing Chu; Yanhong Liu; Chunwen Li; Jianyong Li
2013-01-01
Passivity-based control is widely used in electronic circuit systems because it can utilize their internal structures to facilitate the controller design. In this paper, we first propose a dissipative Hamiltonian realization of power systems and discuss the disadvantages of the traditional passivity-based excitation controller. Then, a novel excitation controller is put forward to reassign the interconnection and dissipative matrix, and the corresponding Hamiltonian function. Simulation resul...
Cholinergic interneurons control local circuit activity and cocaine conditioning.
Witten, Ilana B; Lin, Shih-Chun; Brodsky, Matthew; Prakash, Rohit; Diester, Ilka; Anikeeva, Polina; Gradinaru, Viviana; Ramakrishnan, Charu; Deisseroth, Karl
2010-12-17
Cholinergic neurons are widespread, and pharmacological modulation of acetylcholine receptors affects numerous brain processes, but such modulation entails side effects due to limitations in specificity for receptor type and target cell. As a result, causal roles of cholinergic neurons in circuits have been unclear. We integrated optogenetics, freely moving mammalian behavior, in vivo electrophysiology, and slice physiology to probe the cholinergic interneurons of the nucleus accumbens by direct excitation or inhibition. Despite representing less than 1% of local neurons, these cholinergic cells have dominant control roles, exerting powerful modulation of circuit activity. Furthermore, these neurons could be activated by cocaine, and silencing this drug-induced activity during cocaine exposure (despite the fact that the manipulation of the cholinergic interneurons was not aversive by itself) blocked cocaine conditioning in freely moving mammals.
da Silva, Isaias; Horikawa, Oswaldo; Cardoso, Jose R; Camargo, Fernando A; Andrade, Aron J P; Bock, Eduardo G P
2011-05-01
In previous studies, we presented main strategies for suspending the rotor of a mixed-flow type (centrifugal and axial) ventricular assist device (VAD), originally presented by the Institute Dante Pazzanese of Cardiology (IDPC), Brazil. Magnetic suspension is achieved by the use of a magnetic bearing architecture in which the active control is executed in only one degree of freedom, in the axial direction of the rotor. Remaining degrees of freedom, excepting the rotation, are restricted only by the attraction force between pairs of permanent magnets. This study is part of a joint project in development by IDPC and Escola Politecnica of São Paulo University, Brazil. This article shows advances in that project, presenting two promising solutions for magnetic bearings. One solution uses hybrid cores as electromagnetic actuators, that is, cores that combine iron and permanent magnets. The other solution uses actuators, also of hybrid type, but with the magnetic circuit closed by an iron core. After preliminary analysis, a pump prototype has been developed for each solution and has been tested. For each prototype, a brushless DC motor has been developed as the rotor driver. Each solution was evaluated by in vitro experiments and guidelines are extracted for future improvements. Tests have shown good results and demonstrated that one solution is not isolated from the other. One complements the other for the development of a single-axis-controlled, hybrid-type magnetic bearing for a mixed-flow type VAD.
An all-optical spatial light modulator for field-programmable silicon photonic circuits
Bruck, Roman; Lalanne, Philippe; Mills, Ben; Thomson, David J; Mashanovich, Goran Z; Reed, Graham T; Muskens, Otto L
2016-01-01
Reconfigurable photonic devices capable of routing the flow of light enable flexible integrated-optic circuits that are not hard-wired but can be externally controlled. Analogous to free-space spatial light modulators, we demonstrate all-optical wavefront shaping in integrated silicon-on-insulator photonic devices by modifying the spatial refractive index profile of the device employing ultraviolet pulsed laser excitation. Applying appropriate excitation patterns grants us full control over the optical transfer function of telecommunication-wavelength light travelling through the device, thus allowing us to redefine its functionalities. As a proof-of-concept, we experimentally demonstrate routing of light between the ports of a multimode interference power splitter with more than 97% total efficiency and negligible losses. Wavefront shaping in integrated photonic circuits provides a conceptually new approach toward achieving highly adaptable and field-programmable photonic circuits with applications in optica...
Charge-flux qubit coupled to a tank circuit in strong low-frequency electromagnetic field
International Nuclear Information System (INIS)
A superconducting charge-phase qubit and a coupled high-quality tank circuit in low-frequency electric field have been studied. A fine structure of the multiphoton resonance lines and quantum interference effects associated with excitation of the quasi-two-level system due to the Landau-Zener-Schtukelberg tunneling have been observed. The results obtained us-ing various parameters of the measuring circuit for multiphoton resonance excitations and low-frequency oscillations of average population of quantum levels were compared. The mechanism responsible for the fine structure of resonance lines is considered. The method of measuring the impedance introduced in the tank circuit by oscillations of supercurrent in the qubit and the principal sources of the decoherence are dis-cussed
无刷双馈电动机主要尺寸的探讨%The considerations for basic sizes of brushless doubly-fed machines
Institute of Scientific and Technical Information of China (English)
鲜永菊
2000-01-01
University of Posts and Telecommunications,Chongqing,400065,China Abstract:Based on the principles of electrical machine design and Brushless Doubly-Fed Machines (BDFM),the power relations and electromagnetic loads for BDFM are analyzed and discussed in this paper,then the computational capacity and electromagnetic loads are achieved.This is usefull for the determination of the basic sizes of BDFM.%从传统电机的设计原则和无刷双馈电动机的基本原理出发，对无刷双馈电动机的功率关系及电磁负荷作了详细的分析和讨论，导出了该电动机计算功率、电磁负荷的选取要点，从而确立了无刷双馈电动机主要尺寸确定的主要依据。
Energy Technology Data Exchange (ETDEWEB)
Alexander, Gerald C.; Spee, Rene; Wallace, Alan K.
1993-12-31
Since the inception of the BDFM development program in 1989, the value of BDFM technology has become apparent. The BDFM provides for adjustable speed, synchronous operation while keeping costs associated with the required power conversion equipment lower than in competing technologies. This provides for an advantage in initial as well as maintenance expenses over conventional drive system. Thus, the BDFM enables energy efficient, adjustable speed process control for applications where established drive technology has not been able to deliver satisfactory returns on investment. At the same time, the BDFM challenges conventional drive technologies in established markets by providing for improved performance at lower cost. BDFM converter rating is kept at a minimum, which significantly improves power quality at the utility interface over competing power conversion equipment. In summary, BDFM technology can be expected to provide significant benefits to utilities as well as their customers. This report discusses technical research and development activities related to Phase 3 of the Brushless Doubly-Fed Machine System Development Program, including work made possible by supplemental funds for laboratory improvement and prototype construction. Market research for the BDFM was provided by the College of Business at Oregon State University; market study results will be discussed in a separate report.
Design of Brushless Motor Speed Control System Based on FPGA%基于FPGA的直流无刷电机调速系统的设计
Institute of Scientific and Technical Information of China (English)
郑自伟; 刘兴中
2011-01-01
The design method of brushless DC motor speed control system based on FPGA is introduced. The hardware, software and control method design of speed control system are discussed. The issue of measuring speed using Hall sensor is analyzed and a method of measuring speed of motor based on FPGA is presented. Experiment data shows advantages of the controller, such as high precision and good performance.%介绍基于FPGA芯片的直流无刷电机调速系统的设计方法,讨论了调速系统的硬件结构、软件结构及控制方法的设计及实现。对利用霍尔传感器信号进行测速的问题进行了分析,并给出一种结合FPGA特点的电机转速的解算方法。实验表明,该设计方法性能稳定,调速性能良好。
无刷直流电机转子位置检测方法综述%Summary on Rotor Position Detection Method for Brushless DC Motors
Institute of Scientific and Technical Information of China (English)
赵一衡; 顾伟康; 陈亚彬; 曹翔
2014-01-01
由于受到传统开关器件的限制，大电流开关电源存在功率小、效率低等问题，因此在对PWM软开关技术进行分析后，利用AT89 C52单片机的中断方式输出频率和占空比可调的PWM脉冲，控制大功率开关管GT40 T101的通断，从而实现以模拟继电器的方式控制电路的通断。通过搭建电路验证了PWM软开关在控制大功率电源方面的优越性，对于实际的电气工程应用具有一定的参考价值。%The brushless DC motor (BLDCM) is an advanced mechanical electronic device.Rotor position detection method is an important part of the BLDCM.Traditional method with position sensor is not suitable the need for the current applications because of its own shortcomings, so the position detection method has been the research hotspot recently.The basic principle and research situation of sensorless detection methods are introduced , and their advantages and disadvantages are compared .It provides a certain theoretical basis for researching on sensorless and has certain value.
基于DSC的无刷直流风机控制系统%Control system for brushless DC fan based on DSC
Institute of Scientific and Technical Information of China (English)
徐交建; 吴建华
2011-01-01
Aiming at improving the efficiency and the speed regulating characteristic of fans used in factories, mines and cars, a control system of brushless DC fan based on dsPIC30F4012 which was made by microchip company was investigated and implemented. Hardware system with high reliability was firstly elaborated. Then, the software and the control algorithm were introduced. The system was evaluated by experiments and some conclusions were given. Experiment results show that the system has fine speed regulation performance and high reliability.%为提高厂矿及汽车空调用调速风机的运行效率和调速性能,研究了以Microchip公司的数字信号控制器(DSC) dsPIC30F4012芯片为核心的无刷直流风机控制系统.首先结合风机的使用环境,采用了高可靠性的硬件系统,并对硬件各个部分进行了阐述;然后介绍了系统所使用的控制算法和软件;最后通过实验对整个系统进行了评估并得出一些结论.实验结果证明,该系统能获得良好的调速性能和较高的可靠性.
Bravin, E; Sosa, A
2014-01-01
This report summarizes the results of a series of tests performed on the prototype HIE-ISOLDE diagnostic box (HIE-DB) regarding the vibrations and drifts in the transverse position of the scanning blade while moving in and out of beam path in the HIE-ISOLDE short box prototype. To monitor the transverse position of the blade, a series of 0.1 mm diameter holes were drilled on it and their positions were tracked with an optical system. The linear motion actuator was acquired from UHV design (model LSM38-150-SS), and it was adapted to be driven by a brushless EC motor from MAXON. The speed of the scanning blade during the tests was 10 mm/s. The transverse movement of the slit in the direction perpendicular to the movement was lower than 40 m, and is dominated by the displacement of the contact point of the applied force on the lead-screw. An offset on the slit position was observed while changing the direction of movement of the blade, its amplitude being of the order of 30 m. The amplitudes of the displacements...
Comparison between four piezoelectric energy harvesting circuits
Institute of Scientific and Technical Information of China (English)
Jinhao QIU; Hao JIANG; Hongli JI; Kongjun ZHU
2009-01-01
This paper investigates and compares the efficiencies of four different interfaces for vibration-based energy harvesting systems. Among those four circuits, two circuits adopt the synchronous switching technique, in which the circuit is switched synchronously with the vibration. In this study, a simple source-less trigger circuit used to control the synchronized switch is proposed and two interface circuits of energy harvesting systems are designed based on the trigger circuit. To validate the effectiveness of the proposed circuits, an experimental system was established and the power harvested by those circuits from a vibration beam was measured. Experimental results show that the two new circuits can increase the harvested power by factors 2.6 and 7, respectively, without consuming extra power in the circuits.
Distortion Cancellation via Polyphase Multipath Circuits
Mensink, Eisse; Klumperink, Eric A.M.; Nauta, Bram
2004-01-01
The central question of this paper is: can we enhance the spectral purity of nonlinear circuits with the help of polyphase multipath circuits. Polyphase multipath circuits are circuits with two or more paths that exploit phase differences between the paths to cancel unwanted signals. It turns out that it is very well possible to cancel distortion products produced by a nonlinear circuit. Unfortunately, there are also some spectral components that cannot be cancelled with the polyphase multipa...
Instrumentation and test gear circuits manual
Marston, R M
2013-01-01
Instrumentation and Test Gear Circuits Manual provides diagrams, graphs, tables, and discussions of several types of practical circuits. The practical circuits covered in this book include attenuators, bridges, scope trace doublers, timebases, and digital frequency meters. Chapter 1 discusses the basic instrumentation and test gear principles. Chapter 2 deals with the design of passive attenuators, and Chapter 3 with passive and active filter circuits. The subsequent chapters tackle 'bridge' circuits, analogue and digital metering techniques and circuitry, signal and waveform generation, and p
A New Method for Constructing Circuit Codes
Byrnes, Kevin M.
2016-01-01
Circuit codes are constructed from induced cycles in the graph of the $n$ dimensional hypercube. They are both theoretically and practically important, as circuit codes can be used as error correcting codes. When constructing circuit codes, the length of the cycle determines its accuracy and a parameter called the spread determines how many errors it can detect. We present a new method for constructing a circuit code of spread $k+1$ from a circuit code of spread $k$. This method leads to reco...
Introduction to lethal circuit transformations
Fišer, Petr; Schmidt, Jan
2015-12-01
Logic optimization is a process that takes a logic circuit description (Boolean network) as an input and tries to refine it, to reduce its size and/or depth. An ideal optimization process should be able to devise an optimum implementation of a network in a reasonable time, given any circuit structure at the input. However, there are cases where it completely fails to produce even near-optimum solutions. Such cases are typically induced by non-standard circuit structure modifications. Surprisingly enough, such deviated structures are frequently present in standard benchmark sets too. We may only wonder whether it is an intention of the benchmarks creators, or just an unlucky coincidence. Even though synthesis tools should be primarily well suited for practical circuits, there is no guarantee that, e.g., a higher-level synthesis process will not generate such unlucky structures. Here we present examples of circuit transformations that lead to failure of most of state-of-the-art logic synthesis and optimization processes, both academic and commercial, and suggest actions to mitigate the disturbing effects.
Improved Simulation of Stabilizer Circuits
Aaronson, S; Aaronson, Scott; Gottesman, Daniel
2004-01-01
The Gottesman-Knill theorem says that a stabilizer circuit -- that is, a quantum circuit consisting solely of CNOT, Hadamard, and phase gates -- can be simulated efficiently on a classical computer. This paper improves that theorem in several directions. * By removing the need for Gaussian elimination, we make the simulation algorithm much faster at the cost of a factor-2 increase in the number of bits needed to represent a state. We have implemented the improved algorithm in a freely-available program called CHP (CNOT-Hadamard-Phase), which can handle thousands of qubits easily. * We show that the problem of simulating stabilizer circuits is complete for the classical complexity class ParityL, which means that stabilizer circuits are probably not even universal for classical computation. * We give efficient algorithms for computing the inner product between two stabilizer states, putting any n-qubit stabilizer circuit into a "canonical form" that requires at most O(n^2/log n) gates, and other useful tasks. *...
30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.
2010-07-01
... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment and circuits; overload...
30 CFR 77.800 - High-voltage circuits; circuit breakers.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers. High-voltage circuits supplying power to portable or mobile equipment shall be protected by suitable...
49 CFR 236.5 - Design of control circuits on closed circuit principle.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Design of control circuits on closed circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on closed circuit principle. All control circuits the functioning of which affects safety of train...
Basic electric circuit theory a one-semester text
Mayergoyz, Isaak D
1996-01-01
This is the only book on the market that has been conceived and deliberately written as a one-semester text on basic electric circuit theory. As such, this book employs a novel approach to the exposition of the material in which phasors and ac steady-state analysis are introduced at the beginning. This allows one to use phasors in the discussion of transients excited by ac sources, which makes the presentation of transients more comprehensive and meaningful. Furthermore, the machinery of phasors paves the road to the introduction of transfer functions, which are then used in the analysis of tr
Diamond electro-optomechanical resonators integrated in nanophotonic circuits
Rath, P; Diewald, S; Lewes-Malandrakis, G; Brink, D; Heidrich, N; Nebel, C; Pernice, W H P
2014-01-01
Diamond integrated photonic devices are promising candidates for emerging applications in nanophotonics and quantum optics. Here we demonstrate active modulation of diamond nanophotonic circuits by exploiting mechanical degrees of freedom in free-standing diamond electro-optomechanical resonators. We obtain high quality factors up to 9600, allowing us to read out the driven nanomechanical response with integrated optical interferometers with high sensitivity. We are able to excite higher order mechanical modes up to 115 MHz and observe the nanomechanical response also under ambient conditions.
Noise estimation for deep sub-micron integrated circuits
Institute of Scientific and Technical Information of China (English)
陈彬; 杨华中; 汪惠
2001-01-01
Noise analysis and avoidance are an increasingly critical step in the design of deep submicron (DSM) integrated circuits (Ics). The crosstalk between neighboring interconnects gradually becomes the main noise sources in DSM Ics. We introduce an efficient and accurate noise-evaluation method for capacitively coupled nets of Ics. The method holds for a victim net with arbitrary number of aggressive nets under ramp input excitation. For common RC nets extracted by electronic design automation (EDA) tools, the deviation between our method and HSPICE is under 10%.
Neuromorphic opto-electronic integrated circuits for optical signal processing
Romeira, B.; Javaloyes, J.; Balle, S.; Piro, O.; Avó, R.; Figueiredo, J. M. L.
2014-08-01
The ability to produce narrow optical pulses has been extensively investigated in laser systems with promising applications in photonics such as clock recovery, pulse reshaping, and recently in photonics artificial neural networks using spiking signal processing. Here, we investigate a neuromorphic opto-electronic integrated circuit (NOEIC) comprising a semiconductor laser driven by a resonant tunneling diode (RTD) photo-detector operating at telecommunication (1550 nm) wavelengths capable of excitable spiking signal generation in response to optical and electrical control signals. The RTD-NOEIC mimics biologically inspired neuronal phenomena and possesses high-speed response and potential for monolithic integration for optical signal processing applications.
Circuit model of Rimfire switch
International Nuclear Information System (INIS)
A cascade gaps circuit model for Rimfire switch has been developed. The circuit model includes all stray capacitances and spark channel on-state conduction characteristics. It can not only describe the behavior of Rimfire switch, but also allow analysis of the time varying voltage and current at each part of the switch, describing the internal characters of the switch. PSpice was used to implement the cascade gaps circuit model and simulate a 700 kV Rimfire switch. The simulation shows that, the voltage of the whole switch will be higher than 700 kV when the laser triggered section has broken down but all cascade gaps keep dielectric, and the voltage of all gaps attenuates with high frequency oscillation. (authors)
Additive Manufacturing of Hybrid Circuits
Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.
2016-07-01
There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.
Vertically Integrated Circuits at Fermilab
Energy Technology Data Exchange (ETDEWEB)
Deptuch, Grzegorz; Demarteau, Marcel; Hoff, James; Lipton, Ronald; Shenai, Alpana; Trimpl, Marcel; Yarema, Raymond; Zimmerman, Tom; /Fermilab
2009-01-01
The exploration of the vertically integrated circuits, also commonly known as 3D-IC technology, for applications in radiation detection started at Fermilab in 2006. This paper examines the opportunities that vertical integration offers by looking at various 3D designs that have been completed by Fermilab. The emphasis is on opportunities that are presented by through silicon vias (TSV), wafer and circuit thinning and finally fusion bonding techniques to replace conventional bump bonding. Early work by Fermilab has led to an international consortium for the development of 3D-IC circuits for High Energy Physics. The consortium has submitted over 25 different designs for the Fermilab organized MPW run organized for the first time.
Nuclear sensor signal processing circuit
Kallenbach, Gene A.; Noda, Frank T.; Mitchell, Dean J.; Etzkin, Joshua L.
2007-02-20
An apparatus and method are disclosed for a compact and temperature-insensitive nuclear sensor that can be calibrated with a non-hazardous radioactive sample. The nuclear sensor includes a gamma ray sensor that generates tail pulses from radioactive samples. An analog conditioning circuit conditions the tail-pulse signals from the gamma ray sensor, and a tail-pulse simulator circuit generates a plurality of simulated tail-pulse signals. A computer system processes the tail pulses from the gamma ray sensor and the simulated tail pulses from the tail-pulse simulator circuit. The nuclear sensor is calibrated under the control of the computer. The offset is adjusted using the simulated tail pulses. Since the offset is set to zero or near zero, the sensor gain can be adjusted with a non-hazardous radioactive source such as, for example, naturally occurring radiation and potassium chloride.
Fault Testing for Reversible Circuits
Patel, K N; Markov, I L; Patel, Ketan N.; Hayes, John P.; Markov, Igor L.
2004-01-01
Applications of reversible circuits can be found in the fields of low-power computation, cryptography, communications, digital signal processing, and the emerging field of quantum computation. Furthermore, prototype circuits for low-power applications are already being fabricated in CMOS. Regardless of the eventual technology adopted, testing is sure to be an important component in any robust implementation. We consider the test set generation problem. Reversibility affects the testing problem in fundamental ways, making it significantly simpler than for the irreversible case. For example, we show that any test set that detects all single stuck-at faults in a reversible circuit also detects all multiple stuck-at faults. We present efficient test set constructions for the standard stuck-at fault model as well as the usually intractable cell-fault model. We also give a practical test set generation algorithm, based on an integer linear programming formulation, that yields test sets approximately half the size o...
Design automation for integrated circuits
Newell, S. B.; de Geus, A. J.; Rohrer, R. A.
1983-04-01
Consideration is given to the development status of the use of computers in automated integrated circuit design methods, which promise the minimization of both design time and design error incidence. Integrated circuit design encompasses two major tasks: error specification, in which the goal is a logic diagram that accurately represents the desired electronic function, and physical specification, in which the goal is an exact description of the physical locations of all circuit elements and their interconnections on the chip. Design automation not only saves money by reducing design and fabrication time, but also helps the community of systems and logic designers to work more innovatively. Attention is given to established design automation methodologies, programmable logic arrays, and design shortcuts.
Embedded systems circuits and programming
Sanchez, Julio
2012-01-01
During the development of an engineered product, developers often need to create an embedded system--a prototype--that demonstrates the operation/function of the device and proves its viability. Offering practical tools for the development and prototyping phases, Embedded Systems Circuits and Programming provides a tutorial on microcontroller programming and the basics of embedded design. The book focuses on several development tools and resources: Standard and off-the-shelf components, such as input/output devices, integrated circuits, motors, and programmable microcontrollers The implementat
Circuit modeling for electromagnetic compatibility
Darney, Ian B
2013-01-01
Very simply, electromagnetic interference (EMI) costs money, reduces profits, and generally wreaks havoc for circuit designers in all industries. This book shows how the analytic tools of circuit theory can be used to simulate the coupling of interference into, and out of, any signal link in the system being reviewed. The technique is simple, systematic and accurate. It enables the design of any equipment to be tailored to meet EMC requirements. Every electronic system consists of a number of functional modules interconnected by signal links and power supply lines. Electromagnetic interference
Simplified design of filter circuits
Lenk, John
1999-01-01
Simplified Design of Filter Circuits, the eighth book in this popular series, is a step-by-step guide to designing filters using off-the-shelf ICs. The book starts with the basic operating principles of filters and common applications, then moves on to describe how to design circuits by using and modifying chips available on the market today. Lenk's emphasis is on practical, simplified approaches to solving design problems.Contains practical designs using off-the-shelf ICsStraightforward, no-nonsense approachHighly illustrated with manufacturer's data sheets
Fermionic models with superconducting circuits
Energy Technology Data Exchange (ETDEWEB)
Las Heras, Urtzi; Garcia-Alvarez, Laura; Mezzacapo, Antonio; Lamata, Lucas [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); Solano, Enrique [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, Bilbao (Spain)
2015-12-01
We propose a method for the efficient quantum simulation of fermionic systems with superconducting circuits. It consists in the suitable use of Jordan-Wigner mapping, Trotter decomposition, and multiqubit gates, be with the use of a quantum bus or direct capacitive couplings. We apply our method to the paradigmatic cases of 1D and 2D Fermi-Hubbard models, involving couplings with nearest and next-nearest neighbours. Furthermore, we propose an optimal architecture for this model and discuss the benchmarking of the simulations in realistic circuit quantum electrodynamics setups. (orig.)
Short-circuit impedance measurement
DEFF Research Database (Denmark)
Pedersen, Knud Ole Helgesen; Nielsen, Arne Hejde; Poulsen, Niels Kjølstad
2003-01-01
Methods for estimating the short-circuit impedance in the power grid are investigated for various voltage levels and situations. The short-circuit impedance is measured, preferably from naturally occurring load changes in the grid, and it is shown that such a measurement system faces different...... kinds of problems at different locations in the grid. This means that the best measurement methodology changes depending on the location in the grid. Three typical examples with different measurement problems at 400 kV, 132 kV and 400 V voltage level are discussed....
Circuit, Thermal and Cost Characteristics of Impulse Magnetizing Circuits
Institute of Scientific and Technical Information of China (English)
2000-01-01
This paper describes the development of circuit, thermal and cost model for a capacitor discharge impulse megnetizer and compares simulations to measurements from an actual system. We used a cost structure consisting of five major subsystems for cost modeling. Especially, we estimated the potential for cost reductions impulse magnetizer as a function of time using the learning curve.
Institute of Scientific and Technical Information of China (English)
黄春跃; 周德俭; 黄红艳
2004-01-01
Based on the modal analysis theory and by using the dynamics finite element analysis model of a three-dimensional assembly circuit module, dynamic characteristics of circuit module have been studied, including both natural characteristics analysis and dynamic responses analysis. Using a subspace method, modal analysis is first carried out. The first 6 orders of natural frequencies and vibration modes are obtained. Influence of the number of the Z-shaped metal slices on dynamic characteristics of the entire structure is also studied.Harmonic response analysis is then conducted. The steady-state response when the circuit module is subjected to harmonic excitation is determined. A curve of the response values against frequencies is obtained. As a result, the optimal number of Z-shaped metal slices can be determined, and it can be assured that the three-dimensional assembly circuit module has good performance in terms of the dynamic characteristics.
Application in Circuit Analysis of MATLAB%MATLAB在电路分析中的应用
Institute of Scientific and Technical Information of China (English)
潘骁
2014-01-01
电路分析一直是电子信息工程等相关专业学习的一个难点。本文以一个简单的正弦信号激励的一阶电路为例，先通过传统的分析方法得出解析表达式，然后运用MATLAB/Simulink为平台建模来计算和仿真电路，使得电路的分析变得更加直观。%Circuit analysis has been a difficulty in engineering and other related majors. This paper takes a simple first-order circuit of sinusoidal excitation as an example. Firstly, through traditional analysis, we deduce analytical expression analysis;secondly, by using MATLAB/Simulink, we make models and simulate circuit. In this way, circuit analysis becomes more intuitional.
Relaxation Based Electrical Simulation for VLSI Circuits
Directory of Open Access Journals (Sweden)
S. Rajkumar
2012-06-01
Full Text Available Electrical circuit simulation was one of the first CAD tools developed for IC design. The conventional circuit simulators like SPICE and ASTAP were designed initially for the cost effective analysis of circuits containing a few hundred transistors or less. A number of approaches have been used to improve the performances of congenital circuit simulators for the analysis of large circuits. Thereafter relaxation methods was proposed to provide more accurate waveforms than standard circuit simulators with up to two orders of magnitude speed improvement for large circuits. In this paper we have tried to highlights recently used waveform and point relaxation techniques for simulation of VLSI circuits. We also propose a simple parallelization technique and experimentally demonstrate that we can solve digital circuits with tens of million transistors in a few hours.
An Approach to Simplify Reversible Logic Circuits
Directory of Open Access Journals (Sweden)
Pabitra Roy
2012-09-01
Full Text Available Energy loss is one of the major problems in traditional irreversible circuits. For every bit of information loss kTln2 joules of heat is lost. In order to reduce the energy loss the concept of reversible logic circuits are introduced. Here we have described an algorithm for simplifying the reversible logic circuit and hence reduction of circuit cost and energy. The algorithm considers sub_circuit with respect to their number of lines and contiguous gates. The resulting sub_circuits are re-synthesized with smaller equivalent implementation. The process continues until circuit cost reaches good enough for Application or until a given computation budget has been exhausted. The circuit is constructed by NOT, CNOT and Toffoli gates only. By applying the algorithm and using the equivalent implementation we will get significant reduction of circuit cost and hence energy.
Balancing the excitability of M1 circuitry during movement observation without overt replication
Directory of Open Access Journals (Sweden)
Pablo eArias
2014-09-01
Full Text Available Although observation of a movement increases the excitability of the motor system of the observer, it does not induce a motor replica. What is the mechanism for replica suppression? We performed a series of experiments, involving a total of 66 healthy humans, to explore the excitability of different M1 circuits and the spinal cord during observation of simple movements. Several strategies were used. In the first and second experimental blocks, we used several delay times from movement onset to evaluate the time-course modulation of the cortico-spinal excitability (CSE, and its potential dependency on the duration of the movement observed; in order to do this single pulse transcranial magnetic stimulation (TMS over M1 was used. In subsequent experiments, at selected delay times from movement-onset, we probed the excitability of the cortico-spinal circuits using three different approaches: i electric cervicomedullary stimulation, to test spinal excitability, ii paired-pulse TMS over M1, to evaluate the cortical inhibitory-excitatory balance (short intracortical inhibition SICI and intracortical facilitation ICF and iii continuous theta-burst stimulation (cTBS, to modulate the excitability of M1cortical circuits. We observed a stereotyped response in the modulation of CSE. At 500ms after movement-onset the ICF was increased; although the most clear-cut effect was a decrease of CSE. The compensatory mechanism was not explained by changes in SICI, but by M1-intracortical circuits targeted by cTBS. Meanwhile, the spinal cord maintained the elevated level of excitability induced when expecting to observe movements, potentially useful to facilitate any required response to the movement observed.
基于模糊预测控制的无刷直流电机控制研究%Study on Brushless DC Motor Control Based on Fuzzy Predictive Control
Institute of Scientific and Technical Information of China (English)
王玉娟; 张艳
2015-01-01
针对传统控制方法在对永磁无刷直流电机(Brushless DC Motor,BLDCM)进行控制时鲁棒性差、精度低、实时性不理想等缺点,提出了一种模糊与预测相结合的控制算法。将该算法应用于永磁无刷直流电机双闭环调速系统的转速闭环中,并利用 MATLAB 软件搭建无刷直流电机的控制系统进行仿真。实验结果表明该算法利用模糊控制与预测控制各自的优点,提高了无刷直流电机的性能,是可行和有效的。%When the Brushless DC Motor(BLDCM)is controlled by traditional methods,it is weak in robustness,accuracy and real-time .A fuzzy predictive control method is proposed in this paper.The control algorithm is applied in the double loop of speed servo system of BLDCM.The control system of Brushless DC motor is built and simulated by the MATLAB software.Ex-periments results show that the control algorithm combines the advantages of the fuzzy control and the predictive control and im-proves the performance of the BLDCM.This control method is proved to be feasible and effective.
基于TB6556 FG的降低无刷直流电机噪声的设计%Design for Reducing Noise of Brushless DC Motor Based on TB6556 FG
Institute of Scientific and Technical Information of China (English)
陈治宇; 黄开胜; 陈风凯; 田燕飞; 何建源
2014-01-01
A minitype brushless DC motor of optimal magnet chamfering for 180o sinusoidal driving was designed to reduce vibration and noise of the motor. Firstly sinusoidal drive system was designed with TB6556FG and TP4124AK for suppressing mutation of commutation current;Finite element analysis software of ANSYS was employed to analyze brushless DC motor, and to calculate the optimal magnet chamfering for suppressing torque ripple. The motor was manufactured, and the vibration and noise of brushless DC motor were reduced effectively. This method could improve the characteristics of motors, and it was significant value to reduce vibration and noise of motors.%为降低小型无刷直流电机的振动和噪声，设计了一种180º正弦波驱动的具有最佳磁极削角的无刷直流电机。采用TB6556FG控制器和IPM模块TP4124AK构建正弦波驱动系统，来抑制换向电流的突变。结合ANSYS有限元分析软件对无刷直流电机进行分析，计算出最佳的磁极削角尺寸，来抑制转矩脉动，并进行了样机试验，电机的振动和噪声抑制效果明显。该方法可有效改善电机性能，对降低电机的振动和噪声具有一定的工程应用价值。
From strong to ultrastrong coupling in circuit QED architectures
Energy Technology Data Exchange (ETDEWEB)
Niemczyk, Thomas
2011-08-10
The field of cavity quantum electrodynamics (cavity QED) studies the interaction between light and matter on a fundamental level: a single atom interacts with a single photon. If the atom-photon coupling is larger than any dissipative effects, the system enters the strong-coupling limit. A peculiarity of this regime is the possibility to form coherent superpositions of light and matter excitations - a kind of 'molecule' consisting of an atomic and a photonic contribution. The novel research field of circuit QED extends cavity QED concepts to solid-state based system. Here, a superconducting quantum bit is coupled to an on-chip superconducting one-dimensional waveguide resonator. Owing to the small mode-volume of the resonant cavity, the large dipole moment of the 'artificial atom' and the enormous engineering potential inherent to superconducting quantum circuits, remarkable atom-photon coupling strengths can be realized. This thesis describes the theoretical framework, the development of fabrication techniques and the implementation of experimental characterization techniques for superconducting quantum circuits for circuit QED applications. In particular, we study the interaction between superconducting flux quantum bits and high-quality coplanar waveguide resonators in the strong-coupling limit. Furthermore, we report on the first experimental realization of a circuit QED system operating in the ultrastrong-coupling regime, where the atom-photon coupling rate reaches a considerable fraction of the relevant system frequencies. In these experiments we could observe phenomena that can not be explained within the renowned Jaynes-Cummings model. (orig.)
Striatal cholinergic interneuron regulation and circuit effects
Directory of Open Access Journals (Sweden)
Sean Austin Lim
2014-10-01
Full Text Available The striatum plays a central role in motor control and motor learning. Appropriate responses to environmental stimuli, including pursuit of reward or avoidance of aversive experience all require functional striatal circuits. These pathways integrate synaptic inputs from limbic and cortical regions including sensory, motor and motivational information to ultimately connect intention to action. Although many neurotransmitters participate in striatal circuitry, one critically important player is acetylcholine (ACh. Relative to other brain areas, the striatum contains exceptionally high levels of ACh, the enzymes that catalyze its synthesis and breakdown, as well as both nicotinic and muscarinic receptor types that mediate its postsynaptic effects. The principal source of striatal ACh is the cholinergic interneuron (ChI, which comprises only about 1-2% of all striatal cells yet sends dense arbors of projections throughout the striatum. This review summarizes recent advances in our understanding of the factors affecting the excitability of these neurons through acute effects and long term changes in their synaptic inputs. In addition, we discuss the physiological effects of ACh in the striatum, and how changes in ACh levels may contribute to disease states during striatal dysfunction.
永磁直线直流电机控制系统设计与实验研究%Design and Experiment for Linear Permanent Magnet Brushless DC Motor
Institute of Scientific and Technical Information of China (English)
尹曾锋
2012-01-01
本文详细介绍了基于DSP TMS320LF2407的永磁直线直流无刷电动机硬件设计和PWM控制方法,给出了电机的控制程序流程,试验结果表明该方法简单可行。%This paper introduces a DSP-based PWM timing method for linear permanent magnet brushless DC motor in detail. The test results show that the method of control program is simple and feasible in practice.
Institute of Scientific and Technical Information of China (English)
马余洋
2015-01-01
A kind of high-efficiency DC brushless pumping motor together with its simple manufacturing pro-cess was introduced. The contents were included with the performance of 2-pole PM rotor, detailed stator construction and the manufacturing for the winding as well as relative control method.%介绍了一种效率高且制造工艺简单的无刷直流水泵电机。内容包括两极永磁体转子的性能、定子结构和绕组的制造及其控制方法。
Nehl, T. W.
1980-12-01
A discrete state space model of a power conditioner fed permanent magnet brushless dc motor for aerospace and electric vehicle applications is developed. The parameters which describe that machine portion of this model are derived from a two dimensional nonlinear magnetic field analysis using the finite element method. The model predicts the instantaneous mechanical and electrical behavior of a prototype electromechanical actuator for possible use on board the shuttle orbiter. The model is also used to simulate the instantaneous performance of an advanced electric vehicle propulsion unit. The results of the computer simulations are compared with experimental test data and excellent agreement between the two is found in all cases.
The Research of a novel Method for Brushless Motor Controller based on DSP%基于DSP的新颖无刷直流电机控制器设计
Institute of Scientific and Technical Information of China (English)
赵长青; 范蟠果
2008-01-01
利用DSP2812设计了一个无位置传感器电机控制系统,该系统利用三相四开关电路对无刷直流电机(Brushless DC Motor,简称BLDCM)进行驱动,采用了新颖的无位置传感器控制方法和脉宽调制(PWM)方法.最后通过分析和试验证明了该系统的可行性.
Clocking Scheme for Switched-Capacitor Circuits
DEFF Research Database (Denmark)
Steensgaard-Madsen, Jesper
1998-01-01
A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed.......A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed....
Digital circuit boards mach 1 GHz
Morrison, Ralph
2012-01-01
A unique, practical approach to the design of high-speed digital circuit boards The demand for ever-faster digital circuit designs is beginning to render the circuit theory used by engineers ineffective. Digital Circuit Boards presents an alternative to the circuit theory approach, emphasizing energy flow rather than just signal interconnection to explain logic circuit behavior. The book shows how treating design in terms of transmission lines will ensure that the logic will function, addressing both storage and movement of electrical energy on these lines. It cove
Separating OR, SUM, and XOR Circuits
Find, Magnus; Göös, Mika; Järvisalo, Matti; Kaski, Petteri; Koivisto, Mikko; Korhonen, Janne H.
2013-01-01
Given a boolean n by n matrix A we consider arithmetic circuits for computing the transformation x->Ax over different semirings. Namely, we study three circuit models: monotone OR-circuits, monotone SUM-circuits (addition of non-negative integers), and non-monotone XOR-circuits (addition modulo 2). Our focus is on \\emph{separating} these models in terms of their circuit complexities. We give three results towards this goal: (1) We prove a direct sum type theorem on the monotone complexity of ...
Advanced circuit simulation using Multisim workbench
Báez-López, David; Cervantes-Villagómez, Ofelia Delfina
2012-01-01
Multisim is now the de facto standard for circuit simulation. It is a SPICE-based circuit simulator which combines analog, discrete-time, and mixed-mode circuits. In addition, it is the only simulator which incorporates microcontroller simulation in the same environment. It also includes a tool for printed circuit board design.Advanced Circuit Simulation Using Multisim Workbench is a companion book to Circuit Analysis Using Multisim, published by Morgan & Claypool in 2011. This new book covers advanced analyses and the creation of models and subcircuits. It also includes coverage of transmissi
A circuit mechanism for neurodegeneration.
Roselli, Francesco; Caroni, Pico
2012-10-12
How deficiency in SMN1 selectively affects motoneurons in spinal muscular atrophy is poorly understood. Here, Imlach et al. and Lotti et al. show that aberrant splicing of Stasimon in cholinergic sensory neurons and interneurons leads to motoneuron degeneration, suggesting that altered circuit function may underlie the disorder.
Circuit design for RF transceivers
Leenaerts, Domine; Vaucher, Cicero S
2007-01-01
Second edition of this successful 2001 RF Circuit Design book, has been updated, latest technology reviews have been added as well as several actual case studies. Due to the authors being active in industry as well as academia, this should prove to be an essential guide on RF Transceiver Design for students and engineers.
Integrated Circuit Stellar Magnitude Simulator
Blackburn, James A.
1978-01-01
Describes an electronic circuit which can be used to demonstrate the stellar magnitude scale. Six rectangular light-emitting diodes with independently adjustable duty cycles represent stars of magnitudes 1 through 6. Experimentally verifies the logarithmic response of the eye. (Author/GA)
Unbalanced Neuronal Circuits in Addiction
Volkow, Nora D; Wang, Gen-Jack; Tomasi, Dardo; Baler, Ruben D.
2013-01-01
Through sequential waves of drug-induced neurochemical stimulation, addiction co-opts the brain's neuronal circuits that mediate reward, motivation, , to behavioral inflexibility and a severe disruption of self-control and compulsive drug intake. Brain imaging technologies have allowed neuroscientists to map out the neural landscape of addiction in the human brain and to understand how drugs modify it.
Neural Excitability and Singular Bifurcations.
De Maesschalck, Peter; Wechselberger, Martin
2015-12-01
We discuss the notion of excitability in 2D slow/fast neural models from a geometric singular perturbation theory point of view. We focus on the inherent singular nature of slow/fast neural models and define excitability via singular bifurcations. In particular, we show that type I excitability is associated with a novel singular Bogdanov-Takens/SNIC bifurcation while type II excitability is associated with a singular Andronov-Hopf bifurcation. In both cases, canards play an important role in the understanding of the unfolding of these singular bifurcation structures. We also explain the transition between the two excitability types and highlight all bifurcations involved, thus providing a complete analysis of excitability based on geometric singular perturbation theory.
Excitable laser processing network node in hybrid silicon: analysis and simulation.
Nahmias, Mitchell A; Tait, Alexander N; Shastri, Bhavin J; de Lima, Thomas Ferreira; Prucnal, Paul R
2015-10-01
The combination of ultrafast laser dynamics and dense on-chip multiwavelength networking could potentially address new domains of real-time signal processing that require both speed and complexity. We present a physically realistic optoelectronic simulation model of a circuit for dynamical laser neural networks and verify its behavior. We describe the physics, dynamics, and parasitics of one network node, which includes a bank of filters, a photodetector, and excitable laser. This unconventional circuit exhibits both cascadability and fan-in, critical properties for the large-scale networking of information processors based on laser excitability. In addition, it can be instantiated on a photonic integrated circuit platform and requires no off-chip optical I/O. Our proposed processing system could find use in emerging applications, including cognitive radio and low-latency control. PMID:26480191
Excitable laser processing network node in hybrid silicon: analysis and simulation.
Nahmias, Mitchell A; Tait, Alexander N; Shastri, Bhavin J; de Lima, Thomas Ferreira; Prucnal, Paul R
2015-10-01
The combination of ultrafast laser dynamics and dense on-chip multiwavelength networking could potentially address new domains of real-time signal processing that require both speed and complexity. We present a physically realistic optoelectronic simulation model of a circuit for dynamical laser neural networks and verify its behavior. We describe the physics, dynamics, and parasitics of one network node, which includes a bank of filters, a photodetector, and excitable laser. This unconventional circuit exhibits both cascadability and fan-in, critical properties for the large-scale networking of information processors based on laser excitability. In addition, it can be instantiated on a photonic integrated circuit platform and requires no off-chip optical I/O. Our proposed processing system could find use in emerging applications, including cognitive radio and low-latency control.
Institute of Scientific and Technical Information of China (English)
Bao Bo-Cheng; Feng Fei; Dong Wei; Pan Sai-Hu
2013-01-01
A flux-controlled memristor characterized by smooth cubic nonlinearity is taken as an example,upon which the voltage-current relationships (VCRs) between two parallel memristive circuits-a parallel memristor and capacitor circuit (the parallel MC circuit),and a parallel memristor and inductor circuit (the parallel ML circuit)-are investigated.The results indicate that the VCR between these two parallel memristive circuits is closely related to the circuit parameters,and the frequency and amplitude of the sinusoidal voltage stimulus.An equivalent circuit model of the memristor is built,upon which the circuit simulations and experimental measurements of both the parallel MC circuit and the parallel ML circuit are performed,and the results verify the theoretical analysis results.
Analog Nonvolatile Computer Memory Circuits
MacLeod, Todd
2007-01-01
In nonvolatile random-access memory (RAM) circuits of a proposed type, digital data would be stored in analog form in ferroelectric field-effect transistors (FFETs). This type of memory circuit would offer advantages over prior volatile and nonvolatile types: In a conventional complementary metal oxide/semiconductor static RAM, six transistors must be used to store one bit, and storage is volatile in that data are lost when power is turned off. In a conventional dynamic RAM, three transistors must be used to store one bit, and the stored bit must be refreshed every few milliseconds. In contrast, in a RAM according to the proposal, data would be retained when power was turned off, each memory cell would contain only two FFETs, and the cell could store multiple bits (the exact number of bits depending on the specific design). Conventional flash memory circuits afford nonvolatile storage, but they operate at reading and writing times of the order of thousands of conventional computer memory reading and writing times and, hence, are suitable for use only as off-line storage devices. In addition, flash memories cease to function after limited numbers of writing cycles. The proposed memory circuits would not be subject to either of these limitations. Prior developmental nonvolatile ferroelectric memories are limited to one bit per cell, whereas, as stated above, the proposed memories would not be so limited. The design of a memory circuit according to the proposal must reflect the fact that FFET storage is only partly nonvolatile, in that the signal stored in an FFET decays gradually over time. (Retention times of some advanced FFETs exceed ten years.) Instead of storing a single bit of data as either a positively or negatively saturated state in a ferroelectric device, each memory cell according to the proposal would store two values. The two FFETs in each cell would be denoted the storage FFET and the control FFET. The storage FFET would store an analog signal value
Driver circuit for solid state light sources
Energy Technology Data Exchange (ETDEWEB)
Palmer, Fred; Denvir, Kerry; Allen, Steven
2016-02-16
A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.
Plug-in integrated/hybrid circuit
Stringer, E. J.
1974-01-01
Hybrid circuitry can be installed into standard round bayonet connectors, to eliminate wiring from connector to circuit. Circuits can be connected directly into either section of connector pair, eliminating need for hard wiring to that section.
High energy magnetic excitations
International Nuclear Information System (INIS)
The report emphasizes that the current development in condensed matter physics opens a research field fit to inelastic neutron scattering experiments in the eV range which is easilly accessed by spallation neutron sources. Several important subjects adopted at thermal reactors are shown. It is desired to extend the implementation of the spectroscopic experiments for investigation of higher energy magnetic excitations. For La2CuO4, which is the mother crystal of the first high Tc materials found by Bednortz and Muller, it seems to be believed that the magnetism is well characterized by the two-dimensional Heisenberg antiferromagnetic Hamiltonian, and it is widely accepted that the magnetism is a most probable progenitor of high Tc superconductors. The unusual properties of spin correlations in this crystal have been studied extensively by standard neutron scattering techniques with steady neutrons at BNL. FeSi is not ordered magnetically but shows a very unique feature of temperature induced magnetism, which also has been studied extensively by using the thermal neutron scattering technique at BNL. In these experiments, polarized neutrons are indispensable to extract the clean magnetic components out of other components of non-magnetic scattering. (N.K.)
IMPROVING THE RELIABILITY OF THE POWER CIRCUIT OF THE ELECTRIC TRAINS ЕР2Т AND ЕПЛ2Т
Directory of Open Access Journals (Sweden)
N. H. Visin
2010-02-01
Full Text Available The transitional processes in shunt circuit of traction engines, which armatures and excitation windings are connected in non-conducting direction as to the flowing power current, are considered in this paper. The changes in the control circuits of braking switch and in the shunt power circuit of traction engines with additional mounting a resistor of 0.5 Ohm are proposed. All this modernization will allow increasing greatly the operation reliability of power circuit of ЭР2Т and ЕПЛ2Т electric locomotives during their service life.
Romeira, Bruno; Javaloyes, Julien; Ironside, Charles N; Figueiredo, José M L; Balle, Salvador; Piro, Oreste
2013-09-01
We demonstrate, experimentally and theoretically, excitable nanosecond optical pulses in optoelectronic integrated circuits operating at telecommunication wavelengths (1550 nm) comprising a nanoscale double barrier quantum well resonant tunneling diode (RTD) photo-detector driving a laser diode (LD). When perturbed either electrically or optically by an input signal above a certain threshold, the optoelectronic circuit generates short electrical and optical excitable pulses mimicking the spiking behavior of biological neurons. Interestingly, the asymmetric nonlinear characteristic of the RTD-LD allows for two different regimes where one obtain either single pulses or a burst of multiple pulses. The high-speed excitable response capabilities are promising for neurally inspired information applications in photonics. PMID:24103966
Brain-machine interface circuits and systems
Zjajo, Amir
2016-01-01
This book provides a complete overview of significant design challenges in respect to circuit miniaturization and power reduction of the neural recording system, along with circuit topologies, architecture trends, and (post-silicon) circuit optimization algorithms. The introduced novel circuits for signal conditioning, quantization, and classification, as well as system configurations focus on optimized power-per-area performance, from the spatial resolution (i.e. number of channels), feasible wireless data bandwidth and information quality to the delivered power of implantable system.
Black hole qubit correspondence from quantum circuits
Prudencio, Thiago; Silva, Edilberto O; Belich, Humberto
2014-01-01
We propose a black hole qubit correspondence (BHQC) from quantum circuits, taking into account the BHQC formulations of wrapped brane qubits. With base on BHQC, we implement the corresponding gate operations to realize any given quantum circuit. In particular, we implement cases of the generation of Bell states, quantum teleportation and GHZ states circuits. Finally, we give an interpretation of the BHQC from quantum circuits with base on the BHQC classification of entanglement classes.
Breaking time reversal symmetry in a circuit topological insulator
Owens, Clai; Jia, Ningyuan; Sommer, Ariel; Schuster, David; Simon, Jonathan
2014-05-01
Materials exhibiting knotted band-structures provide a unique window on interplay between topology and quantum mechanics under well-controlled conditions. The main difficulty is engineering a strong background gauge field for the electrically neutral ``particles'' that comprise such materials. In cold atom systems, the leading candidates include Raman couplings, lattice modulation, and optical flux lattices; however no scalable approach has yet been demonstrated. Meta-materials have seen substantial success, both in coupled optical waveguides, and circuit networks. Here we describe progress towards time reversal breaking in a circuit, to split up- and down- spin Chern bands. This work is essential for studies of fractional quantum hall physics, where spin-flip collisions effectively reverse the magnetic field and destroy the many-body state. We present the design of a 1D transmission line that breaks time reversal symmetry via periodic capacitance modulation. We extend this approach to a 2D geometry, realizing a Floquet topological insulator with an isolated ground Chern-band. These tools are compatible with circuit quantum electrodynamics techniques, and thus provide an exciting route to studies of topologically ordered phases of matter.
Subsurface excitations in a metal
DEFF Research Database (Denmark)
Ray, M. P.; Lake, R. E.; Sosolik, C. E.;
2009-01-01
by the free-electron model of a metal still excite hot carriers. Excellent agreement between these results and a nonadiabatic model that accounts for the time-varying ion-surface interaction indicates that the measured excitations are due to semilocalized electrons near the metal surface....
49 CFR 236.721 - Circuit, control.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, control. 236.721 Section 236.721..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.721 Circuit, control. An electrical circuit between a source of electric energy and a device which it operates....
Equivalence Checking of Hierarchical Combinational Circuits
DEFF Research Database (Denmark)
Williams, Poul Frederick; Hulgaard, Henrik; Andersen, Henrik Reif
1999-01-01
This paper presents a method for verifying that two hierarchical combinational circuits implement the same Boolean functions. The key new feature of the method is its ability to exploit the modularity of circuits to reuse results obtained from one part of the circuits in other parts. We demonstrate...
An eigenvalue study of the MLC circuit
DEFF Research Database (Denmark)
Lindberg, Erik; Murali, K.
1998-01-01
The MLC (Murali-Lakshmanan-Chua) circuit is the simplest non-autonomous chaotic circuit. Insight in the behaviour of the circuit is obtained by means of a study of the eigenvalues of the linearized Jacobian of the nonlinear differential equations. The trajectories of the eigenvalues as functions...
An Equivalent Circuit for Landau Damping
DEFF Research Database (Denmark)
Pécseli, Hans
1976-01-01
An equivalent circuit simulating the effect of Landau damping in a stable plasma‐loaded parallel‐plate capacitor is presented. The circuit contains a double infinity of LC components. The transition from stable to unstable plasmas is simulated by the introduction of active elements into the circuit....
49 CFR 236.731 - Controller, circuit.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Controller, circuit. A device for opening and closing electric circuits....
A Current-mode Logarithmic Function Circuit
Osama Oglah Faris; Muhammad Taher Abuelma'atti
2004-01-01
A new current-mode analog circuit configuration that implements the function ln (x/y) is proposed. The circuit uses bipolar transistors and resistors and is suitable for integration. In the proposed circuit the ratio (x/y) can be larger or smaller than unity. Simulation results are included.
47 CFR 32.2232 - Circuit equipment.
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment... which is used for the amplification, modulation, regeneration, circuit patching, balancing or control...
49 CFR 236.726 - Circuit, track.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....
30 CFR 56.6407 - Circuit testing.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit testing. 56.6407 Section 56.6407... Blasting § 56.6407 Circuit testing. A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test each of the following: (a) Continuity of each electric detonator...
30 CFR 57.6407 - Circuit testing.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit testing. 57.6407 Section 57.6407... Blasting-Surface and Underground § 57.6407 Circuit testing. A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test the following: (a) In surface operations—...
30 CFR 75.1323 - Blasting circuits.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting circuits. 75.1323 Section 75.1323... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made...
Institute of Scientific and Technical Information of China (English)
崔新风; 娄建安; 褚杰; 原亮; 丁国良
2011-01-01
为解决目前数字型演化硬件研究中存在的电路编码困难问题,提出一个可用矩阵形式描述组合电路的类神经网络门级电路模型,讨论在此模型上进行电路编码的具体方法.根据编码矩阵特点,对标准遗传算法进行改进,设计遗传操作算子、适应度评估方法等.通过无刷直流电动机电子换相电路的成功演化实例,验证了采用矩阵编码和改进遗传算法实现数字电路演化的可行性.%For the purpose of solving the encoding problem harassed the digital Evolvable Hardware(EHW) researchers, a gate-level circuit model which is based on the similarities between combinatorial circuit and neural network is proposed, on which the matrix encoding scheme of combinatorial circuit is discussed. An improved genetic algorithm is used to evolve the encoding matrix, genetic operators and fitness evaluation method are designed according to the characteristics of circuit encoding. The implementation of the commutation circuit of brushless direct current motor proves the feasibility of the implementation method of digital EHW by the using of matrix encoding scheme and the improved genetic algorithm.
Energy harvesting under excitation of clamped-clamped beam
Batra, Ashok; Alomari, Almuatasim; Aggarwal, Mohan; Bandyopadhyay, Alak
2016-04-01
In this article, a piezoelectric energy harvesting has been developed experimentally and theoretically based on Euler- Bernoulli Theory. A PVDF piezoelectric thick film has attached along of clamped-clamped beam under sinusoidal base excitation of shaker. The results showed a good agreement between the experimental and simulation of suggested model. The voltage output frequency response function (FRF), current FRF, and output power has been studied under short and open circuit conditions at first vibration mode. The mode shape of the clamped-clamped beam for first three resonance frequency has been modeled and investigated using COMSOL Multiphysics and MATLAB.
Multiple phonon excitation in nuclei
International Nuclear Information System (INIS)
The studies of multiphonon excitations in nuclei are reviewed both from the theoretical and experimental points of view. The presence of giant resonances in nuclei is described in the framework of macroscopic and microscopic models and the relative merits of different probes to excite such states are illustrated. The existence of giant resonances built on excited states is stressed. An exhaustive description of the theoretical estimates of the properties of the multiphonon states is presented. The theory predicts that such multiple collective excitations should closely follow a harmonic pattern. Recent experimental results on the double giant dipole resonance using the (π+π-) double charge exchange reaction are shown. The status of the search for isoscalar multiphonon excitations by means of the strong nuclear potential produced by heavy ions is presented. Conclusions are drawn and new prospects are discussed. (authors) 293 refs., 67 figs., 8 tabs
Integrated circuits for multimedia applications
DEFF Research Database (Denmark)
Vandi, Luca
2007-01-01
, and it is applied to a broad-band dual-loop receiver architecture in order to boost the linearity performances of the stage. A simplified noise- and linearity analysis of the circuit is derived, and a comparison is provided with a more traditional dual-loop topology (a broad-band stage based on shunt......This work presents several key aspects in the design of RF integrated circuits for portable multimedia devices. One chapter is dedicated to the application of negative-feedback topologies to receiver frontends. A novel feedback technique suitable for common multiplier-based mixers is described......-series feedback), showing a difference in compression point in the order of 10dBm for the same power consumption. The same principle is also applied to a more conventional narrow-band stage in which a single loop is employed in order to enhance noise performances. Noise analysis shows sensible improvements...
Handbook of microwave integrated circuits
Hoffmann, Reinmut K.
The design and operation of ICs for use in the 0.5-20-GHz range are described in an introductory and reference work for industrial engineers. Chapters are devoted to an overview of microwave IC (MIC) technology, general stripline characteristics, microwave transmission line (MTL) parameters for microstrips with isotropic dielectric substrates, higher-order modes on a microstrip, the effects of metallic enclosure on MTL transmission parameters, losses in microstrips, the measurement of MTL parameters, and MTLs on anisotropic dielectric substrates. Consideration is given to coupled microstrips on dielectric substrates, microstrip discontinuities, radiation from microstrip circuits, MTL variations, coplanar MTLs, slotlines, and spurious modes in MTL circuits. Diagrams, drawings, graphs, and a glossary of symbols are provided.
Ionization tube simmer current circuit
Steinkraus, Jr., Robert F.
1994-01-01
A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.