Operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage

International Nuclear Information System (INIS)

Jou, Hurng-Liahng; Chang, Yi-Hao; Wu, Jinn-Chang; Wu, Kuen-Der

2015-01-01

Highlights: • The operation strategy for grid-connected PV generation system integrated with battery energy storage is proposed. • The PV system is composed of an inverter and two DC-DC converter. • The negative impact of grid-connected PV generation systems on the grid can be alleviated by integrating a battery. • The operation of the developed system can be divided into nine modes. - Abstract: The operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage is proposed in this paper. The photovoltaic generation system is composed of a full-bridge inverter, a DC–DC boost converter, an isolated bidirectional DC–DC converter, a solar cell array and a battery set. Since the battery set acts as an energy buffer to adjust the power generation of the solar cell array, the negative impact on power quality caused by the intermittent and unstable output power from a solar cell array is alleviated, so the penetration rate of the grid-connected photovoltaic generation system is increased. A lab-scale prototype is developed to verify the performance of the system. The experimental results show that it achieves the expected performance

Experimental evaluation of 8kW grid-connected photovoltaic system in Egypt

OpenAIRE

Elkholy, A.; Fahmy, F.H.; Abou El-Ela, A.A.; Nafeh, Abd El-Shafy A.; Spea, S.R.

2016-01-01

An experimental observation study of 8 kW grid-connected photovoltaic (PV) system that is installed at Electronics Research Institute (ERI), Giza, Egypt (Latitude 30.04°N, Longitude 31.21°E), is presented. This study includes the quality of the electrical power generated and injected into the network. The considered system consists of 28 × 295 Wp multicrystalline PV modules, StecaGrid three-phase 8 kW grid-connected inverter and a Solar-Log 300 PM+ for data acquisition and remote monitoring. ...

Control of Grid Connected Photovoltaic Systems with Microinverters

DEFF Research Database (Denmark)

Yahya, Abdelhafid; El Fadil, Hassan; Oulcaid, Mustapha

2018-01-01

This paper addresses the problem of controlling grid connected photovoltaic (PV) systems that are driven with microinverters. The systems to be controlled consist of a solar panel, a boost dc–dc converter, a DC link capacitor, a single-phase full-bridge inverter, a filter inductor, and an isolation...... transformer. We seek controllers that are able to simultaneously achieve four control objectives, namely: (i) asymptotic stability of the closed loop control system; (ii) maximum power point tracking (MPPT) of the PV module; (iii) tight regulation of the DC bus voltage; and (iv) unity power factor (PF...

Research on Experiment of Islanding Protection Device of Grid-connected Photovoltaic System Based on RTDS

Science.gov (United States)

Zhou, Ning; Yang, Jia; Cheng, Zheng; Chen, Bo; Su, Yong Chun; Shu, Zhan; Zou, Jin

2017-06-01

Solar photovoltaic power generation is the power generation using solar cell module converting sunlight into DC electric energy. In the paper an equivalent model of solar photovoltaic power generation system is built in RTDS. The main circuit structure of the two-stage PV grid-connected system consists of the DC-DC, DC-AC circuit. The MPPT (Maximum Power Point Tracking) control of the PV array is controlled by adjusting the duty ratio of the DC-DC circuit. The proposed control strategy of constant voltage/constant reactive power (V/Q) control is successfully implemented grid-connected control of the inverter when grid-connected operation. The closed-loop experiment of islanding protection device of photovoltaic power plant on RTDS, verifies the correctness of the simulation model, and the experimental verification can be applied to this type of device.

A software application for energy flow simulation of a grid connected photovoltaic system

International Nuclear Information System (INIS)

Hamad, Ayman A.; Alsaad, Mohammad A.

2010-01-01

A computer software application was developed to simulate hourly energy flow of a grid connected photovoltaic system. This software application enables conducting an operational evaluation of a studied photovoltaic system in terms of energy exchange with the electrical grid. The system model consists of a photovoltaic array, a converter and an optional generic energy storage component that supports scheduled charging/discharging. In addition to system design parameters, the software uses hourly solar data and hourly load data to determine the amount of energy exchanged with electrical grid for each hour of the simulated year. The resulting information is useful in assessing the impact of the system on demand for electrical energy of a building that uses it. The software also aggregates these hourly results in daily, monthly and full year sums. The software finds the financial benefit of the system as the difference in grid electrical energy cost between two simultaneously considered cases. One is with load supplied only by the electrical grid, while the other is with the photovoltaic system present and contributing energy. The software supports the energy pricing scheme used in Jordan for domestic consumers, which is based on slices of monthly consumption. By projecting the yearly financial results on the system lifetime, the application weighs the financial benefit resulting from using the system against its cost, thus facilitating an economical evaluation.

An integrative approach to the design methodology for 3-phase power conditioners in Photovoltaic Grid-Connected systems

International Nuclear Information System (INIS)

Rey-Boué, Alexis B.; García-Valverde, Rafael; Ruz-Vila, Francisco de A.; Torrelo-Ponce, José M.

2012-01-01

Highlights: ► A design methodology for Photovoltaic grid-connected systems is presented. ► Models of the Photovoltaic Generator and the 3-phase Inverter are described. ► The power factor and the power quality are regulated with vector control. ► Simulation and experimental results validate the design methodology. ► The proposed methodology can be extended to any Renewable or Industrial System. - Abstract: A novel methodology is presented in this paper, for the design of the Power and Control Subsystems of a 3-phase Photovoltaic Grid-Connected system in an easy and comprehensive way, as an integrative approach. At the DC side of the Power Subsystem, the Photovoltaic Generator modeling is revised and a simple model is proposed, whereas at the AC side, a vector analysis is done to deal with the instantaneous 3-phase variables of the grid-connected Voltage Source Inverter. A d–q control approach is established in the Control Subsystem, along with its specific tuned parameters, as a vector control alternative which will allow the decoupled control of the instantaneous active and reactive powers. A particular Case of Study is presented to illustrate the behavior of the design methodology regarding the fulfillment of the Photovoltaic plant specifications. Some simulations are run to study the performance of the Photovoltaic Generator together with the exerted d–q control to the grid-connected 3-phase inverter, and some experimental results, obtained from a built flexible platform, are also shown. The simulations and the experimental results validate the overall performance of the 3-phase Photovoltaic Grid-Connected system due to the attained unitary power factor operation together with good power quality. The final validation of the proposed design methodology is also achieved.

Digital proportional multi-resonant current controller for improving grid-connected photovoltaic systems

NARCIS (Netherlands)

Almeida, de P.M.; Barbosa, P.G.; Oliveira, J.G.; Duarte, J.L.; Ribeiro, P.F.

2015-01-01

This paper presents the modelling and design steps of a digital proportional multi-resonant controller used in a grid-connected photovoltaic (PV) system. It is shown that the use of only one Proportional-Resonant (PR) compensator, tuned to the system fundamental frequency, may have its effectiveness

The effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria

Science.gov (United States)

Zaghba, L.; Khennane, M.; Terki, N.; Borni, A.; Bouchakour, A.; Fezzani, A.; Mahamed, I. Hadj; Oudjana, S. H.

2017-02-01

This paper presents modeling, simulation, and analysis evaluation of the grid-connected PV generation system performance under MATLAB/Simulink. The objective is to study the effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria. This system works with a power converter. This converter allows the connection to the network and extracts maximum power from photovoltaic panels with the MPPT algorithm based on robust neuro-fuzzy sliding approach. The photovoltaic energy produced by the PV generator will be completely injected on the network. Simulation results show that the system controlled by the neuro-fuzzy sliding adapts to changing external disturbances and show their effectiveness not only for continued maximum power point but also for response time and stability.

A report on the performance of a grid connected photovoltaic power generation system

International Nuclear Information System (INIS)

Mohd Azhar Abdul Rahman; Mohd Surif Abdul Wahab; Azmi Omar

2000-01-01

Malaysia is located almost on the equator and is blessed with an abundance of sunlight almost all year round. So obviously, with the right planning and strategies that are coupled to the right technology and development in the market, the potential for photovoltaic system as an alternative source of power in this country looks promising and is constantly gaining ground and popularity. Sunlight is free and the photovoltaic system is also emission and pollution free which is a guest boost to the current worldwide effort to reduce the global environmental problems. Utility giant Tenaga Nasional Berhad is in line with the Government aspiration to promote the development of solar photovoltaic in the country, who believe in the success and acceptance potential of the photovoltaic system as an alternative source of power generation for long term energy option. In March 1998, a contract was awarded by Tenaga Nasional Berhad to its research subsidiary, Tenaga Nasional Research and Development Sdn. Bhd. to undertake a pilot research project on the development of a grid connected photovoltaic system. This research project is co-funded by the Electric Supply Industry Trust fund. One of the main objective of this research project is to seek the best approach to popularize the Grid Connected Photovoltaic System for domestic as well as suitable commercial premises in this country. This paper will report the initial findings of the project in terms of technical capability and commercial liability. (Author)

Investigation of the behavior of a three phase grid-connected photovoltaic system to control active and reactive power

Energy Technology Data Exchange (ETDEWEB)

Tsengenes, Georgios; Adamidis, Georgios [Department of Electrical Engineering and Computer Engineering, Democritus University of Thrace, University Campus Kimmeria, 67100 Xanthi (Greece)

2011-01-15

In this paper, a photovoltaic (PV) system, with maximum power point tracking (MPPT), connected to a three phase grid is presented. The connection of photovoltaic system on the grid takes place in one stage using voltage source inverter (VSI). For a better utilization of the photovoltaic system, the control strategy applied is based on p-q theory. According to this strategy during sunlight the system sends active power to the grid and at the same time compensates the reactive power of the load. In case there is no sunlight (during the night for instance), the inverter only compensates the reactive power of the load. In this paper the use of p-q theory to supply the grid with active power and compensate the reactive power of the load is investigated. The advantage of this control strategy is that the photovoltaic system is operated the whole day. Furthermore, the p-q theory uses simple algebraic calculations without demanding the use of PLL to synchronize the inverter with the grid. (author)

Ground-Fault Characteristic Analysis of Grid-Connected Photovoltaic Stations with Neutral Grounding Resistance

Directory of Open Access Journals (Sweden)

Zheng Li

2017-11-01

Full Text Available A centralized grid-connected photovoltaic (PV station is a widely adopted method of neutral grounding using resistance, which can potentially make pre-existing protection systems invalid and threaten the safety of power grids. Therefore, studying the fault characteristics of grid-connected PV systems and their impact on power-grid protection is of great importance. Based on an analysis of the grid structure of a grid-connected PV system and of the low-voltage ride-through control characteristics of a photovoltaic power supply, this paper proposes a short-circuit calculation model and a fault-calculation method for this kind of system. With respect to the change of system parameters, particularly the resistance connected to the neutral point, and the possible impact on protective actions, this paper achieves the general rule of short-circuit current characteristics through a simulation, which provides a reference for devising protection configurations.

Grid-connected of photovoltaic module using nonlinear control

DEFF Research Database (Denmark)

El Fadil, H.; Giri, F.; Guerrero, Josep M.

2012-01-01

The problem of controlling single-phase grid connected photovoltaic (PV) system is considered. The control objective is fourfold: (i) asymptotic stability of the closed loop system, (ii) maximum power point tracking (MPPT) of PV module (iii) tight regulation of the DC bus voltage, and (iv) unity...

Control strategy based on SPWM switching patterns for grid connected photovoltaic inverter

Science.gov (United States)

Hassaine, L.; Mraoui, A.

2017-02-01

Generally, for lower installation of photovoltaic systems connected to the grid, pulse width modulation (PWM) is a widely used technique for controlling the voltage source inverters injects currents into the grid. The current injected must be sinusoidal with reduced harmonic distortion. In this paper, a digital implementation of a control strategy based on PWM switching patterns for an inverter for photovoltaic system connected to the grid is presented. This strategy synchronize a sinusoidal inverter output current with a grid voltage The digital implementation of the proposed PWM switching pattern when is compared with the conventional one exhibit the advantage: Simplicity, reduction of the memory requirements and power calculation for the control

Sensorless Reserved Power Control Strategy for Two-Stage Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2016-01-01

Due to still increasing penetration level of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A reserved power control, where the active power from the PV panels is reserved during operation, is required for grid...... support. In this paper, a cost-effective solution to realize the reserved power control for grid-connected PV systems is proposed. The proposed solution routinely employs a Maximum Power Point Tracking (MPPT) control to estimate the available PV power and a Constant Power Generation (CPG) control...... to achieve the power reserve. In this method, the irradiance measurements that have been used in conventional control schemes to estimate the available PV power are not required, and thereby being a sensorless solution. Simulations and experimental tests have been performed on a 3-kW two-stage single...

Performance of Grid-Connected Photovoltaic System in Two Sites in Kuwait

Directory of Open Access Journals (Sweden)

Ali Hajiah

2012-01-01

Full Text Available This paper presents an assessment of the electricity generated by photovoltaic (PV grid-connected systems in Kuwait. Three years of meteorological data are provided for two main sites in Kuwait, namely, Al-Wafra and Mutla. These data and a PV grid-connected system mathematical model are used to assist a 100 kWp grid-connected PV system proposed for both sites. The proposed systems show high energy productivity whereas the annual capacity factors for Mutla and Al-Wafra are 22.25% and 21.6%, respectively. Meanwhile the annual yield factors for Mutla and Al-Wafra are 1861 kWh/kWp/year and 1922.7 kWh/kWp/year, respectively. On the other hand the cost of the energy generated by both systems is about 0.1 USD/kWh which is very close to the price of the energy sold by the Ministry of Electricity and Water (MEW. Furthermore the invested money is recovered during the assumed life cycle time whereas the payback period for both sites is about 15 years. This work contains worthwhile technical information for those who are interested in PV technology investment in Kuwait.

Model Building of Photovoltaic Array with MPPT Function and Research on Single Phase Grid Connected

Directory of Open Access Journals (Sweden)

Li Zhengzhou

2016-01-01

Full Text Available With the continued development of solar photovoltaic technology, research on distributed grid connected photovoltaic system has become a research focus in the field of photovoltaic grid power plant and the computer simulation technology is an effective technology means in the study. On the basis of the photovoltaic array output characteristic equation, the photovoltaic array maximum power control simulation model based on M function is established by using MATLAB/Simulink and the simulation model of single phase grid connected photovoltaic array is proposed. It overcomes the shortcomings of the process of building the model of the PV array by using Simulink component library and provides the basic guarantee for the realization of system simulation, guiding theory research and system design.

Two-stage single-phase grid-connected photovoltaic system with reduced complexity

Science.gov (United States)

da Silva, Cintia S.; Motta, Filipe R.; Tofoli, Fernando L.

2011-06-01

This article presents a grid-connected photovoltaic (PV) system using the classical DC-DC buck converter, which is responsible for stepping down the resulting voltage from several series-connected panels. Besides, the structure provides high power factor operation by injecting a quasi-sinusoidal current into the grid, with near no displacement in relation to the line voltage at the point of common coupling among the PV system and the loads. A CSI employing thyristors is cascaded with the DC-DC stage so that AC voltage results. The inverter output voltage level is adjusted by using a low-frequency transformer, which also provides galvanic isolation. The proposed system is described as mathematical approach and design guidelines are presented, providing an overview of the topology. An experimental prototype is also implemented, and relevant results to validate the proposal are discussed.

Analysis and Modeling of Interharmonics from Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

2018-01-01

The industry of solar Photovoltaic (PV) energy and its exploitation are still booming to enhance the sustainability of the society. When PV systems are connected to the grid, challenging issues should be addressed. One of the challenges is related to interharmonics in PV systems, especially...... with a largescale adoption of PV systems. However, the origins of interharmonics remain unclear, although the impact of interhamonics has been reported in literature. Thus, this paper explores the generation mechanisms of interharmonics in PV systems and its characteristics. The exploration reveals...... that the perturbation from the Maximum Power Point Tracking (MPPT) algorithm is one of the origins of interharmonics appearing in the grid current. Accordingly, the MPPT controller parameters such as the perturbation step-size and the sampling rate have an inevitable impact on the interharmonic characteristics...

Zero-voltage ride-through capability of single-phase grid-connected photovoltaic systems

DEFF Research Database (Denmark)

Zhang, Zhen; Yang, Yongheng; Ma, Ruiqing

2017-01-01

Distributed renewable energy systems play an increasing role in today’s energy paradigm. Thus, intensive research activities have been centered on improving the performance of renewable energy systems, including photovoltaic (PV) systems, which should be of multiple-functionality. That is, the PV...... systems should be more intelligent in the consideration of grid stability, reliability, and fault protection. Therefore, in this paper, the performance of single-phase grid-connected PV systems under an extreme grid fault (i.e., when the grid voltage dips to zero) is explored. It has been revealed...... that combining a fast and accurate synchronization mechanism with appropriate control strategies for the zero-voltage ride-through (ZVRT) operation is mandatory. Accordingly, the representative synchronization techniques (i.e., the phase-locked loop (PLL) methods) in the ZVRT operation are compared in terms...

Performance Analysis of 14 MW Grid-Connected Photovoltaic System

International Nuclear Information System (INIS)

Kagilik, Ahmed S.; Tawel, Abduraouf M.

2015-01-01

Many Libyan authorities proposed to investigate the possibility of utilizing a suitable terrain in Libya to add generation capacity of large-scale photovoltaic power plants. In this paper, the first grid-connected PV plant of 14 MWp which will be executed in Hoon city and supported by the Renewable Energy Authority of Libya (REAOL) is presented. To understand and improve the operational behavior of PV system, a comprehensive study including the plant design and detailed performance analysis under a local climate conditions is performed. Using polycrystalline silicon technology, the first year energy yield is estimated and the monthly system output for this plant is calculated. The performance ratio and various power losses (temperature, irradiance, power electronics, interconnection, etc.) are determined. The PV system supplied 24964 MWh to the grid during the first year giving an average annual overall yield factor 1783 kWh/kWp and average annual performance ratio of the system of 76.9%.(author)

Benchmarking of grid fault modes in single-phase grid-connected photovoltaic systems

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

2012-01-01

Pushed by the booming installations of single-phase photovoltaic (PV) systems, the grid demands regarding the integration of PV systems are expected to be modified. Hence, the future PV systems should become more active with functionalities of low voltage ride-through (LVRT) and the grid support...

Impact of Rural Grid-Connected Photovoltaic Generation Systems on Power Quality

Directory of Open Access Journals (Sweden)

Rita Pinto

2016-09-01

Full Text Available Photovoltaic (PV generation systems have been increasingly used to generate electricity from renewable sources, attracting a growing interest. Recently, grid connected PV micro-generation facilities in individual homes have increased due to governmental policies as well as greater attention by industry. As low voltage (LV distribution systems were built to make energy flow in one direction, the power feed-in of PV generation in rural low-voltage grids can influence power quality (PQ as well as facility operation and reliability. This paper presents results on PQ analysis of a real PV generation facility connected to a rural low-voltage grid. Voltage fluctuations and voltage harmonic contents were observed. Statistical analysis shows a negative impact on PQ produced by this PV facility and also that only a small fraction of the energy available during a sunny day is converted, provoking losses of revenue and forcing the converter to work in an undesirable operating mode. We discuss the disturbances imposed upon the grid and their outcome regarding technical and economic viability of the PV system, as well as possible solutions. A low-voltage grid strengthening has been suggested and implemented. After that a new PQ analysis shows an improvement in the impact upon PQ, making this facility economically viable.

Online Variable Topology-Type Photovoltaic Grid-Connected Inverter

DEFF Research Database (Denmark)

Wu, Fengjiang; Sun, Bo; Duan, Jiandong

2015-01-01

In photovoltaic (PV) grid-connected generation system, the key focus is how to expand the generation range of the PV array and enhance the total efficiency of the system. This paper originally derived expressions of the total loss and grid current total harmonics distortions of cascaded inverter...... and H-bridge inverter under the conditions of variable output voltage and power of the PV array. It is proved that, compared with the H-bridge inverter, the operation range of the cascaded inverter is wider, whereas the total loss is larger. Furthermore, a novel online variable topology-type grid......-connected inverter is proposed. A bidirectional power switch is introduced into the conventional cascaded inverter to connect the negative terminals of the PV arrays. When the output voltages of the PV arrays are lower, the proposed inverter works under cascaded inverter mode to obtain wider generation range. When...

Analysis of the influences of grid-connected PV power system on distribution grids

Directory of Open Access Journals (Sweden)

Dumitru Popandron

2013-12-01

Full Text Available This paper presents the analysis of producing an electric power of 2.8 MW using a solar photovoltaic plant. The PV will be grid connected to the distribution network. The study is focused on the influences of connecting to the grid of a photovoltaic system, using modern software for analysis, modeling and simulation in power systems.

A Cost-Effective Power Ramp-Rate Control Strategy for Single-Phase Two-Stage Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2016-01-01

In the case of a wide-scale adoption of grid-connected Photovoltaic (PV) systems, more fluctuated power will be injected into the grid due to the intermittency of solar PV energy. A sudden change in the PV power can potentially induce grid voltage fluctuations, and thus challenge the stability......-point. Experiments conducted on a 3-kW single-phase two-stage grid-connected PV system have verified that the proposed solution can accomplish fast dynamics, high accuracy, and high robustness in the power ramp-rate control for PV systems....

Performance Ratios of Grid Connected Photovoltaic Systems and Theory of Errors

Directory of Open Access Journals (Sweden)

Javier Vilariño-García

2016-07-01

Full Text Available A detailed analysis of the different levels of dynamic performance of grid connected photovoltaic systems and its interface based on the development of a block diagram explaining the course of energy transformation from solar radiation incident on the solar modules until it becomes useful energy available in the mains. Indexes defined by the Spanish standard                 UNE-EN 61724: Monitoring photovoltaic systems: Guidelines for measurement, data exchange and analysis, are explained from the basics fundaments of block algebra and the transfer function of linear systems. The accuracy requirements demanded by the aforementioned standard for measuring these parameters are discussed in the theory of errors and the real limits of the results obtained. 

Performance evaluation of 10 MW grid connected solar photovoltaic power plant in India

OpenAIRE

B. Shiva Kumar; K. Sudhakar

2015-01-01

The growing energy demand in developing nations has triggered the issue of energy security. This has made essential to utilize the untapped potential of renewable resources. Grid connected PV systems have become the best alternatives in renewable energy at large scale. Performance analysis of these grid connected plants could help in designing, operating and maintenance of new grid connected systems. A 10 MW photovoltaic grid connected power plant commissioned at Ramagundam is one of the larg...

Performance and economic analysis of a 27 kW grid-connected photovoltaic system in Suriname

NARCIS (Netherlands)

Raghoebarsing, Amrita; Kalpoe, Anand

2017-01-01

The performance of a grid-connected photovoltaic (PV) system, under the Surinamese weather conditions, is monitored and reported. A measurement and data-logging system provides inputs for the calculation of selected standard key performance indicators (KPI). Calculated KPI's are compared to expected

Reliability Oriented Design of a Grid-Connected Photovoltaic Microinverter

DEFF Research Database (Denmark)

Shen, Yanfeng; Wang, Huai; Blaabjerg, Frede

2017-01-01

High reliability performance of microinverters in Photovoltaic (PV) systems is a merit to match lifetime with PV panels, and to reduce the required maintenance efforts and costs. This digest applies a reliability oriented design method for a grid-connected PV microinverter to achieve specific...

REVIEW ON GRID INTERFACING OF MULTIMEGAWATT PHOTOVOLTAIC INVERTERS

OpenAIRE

Mr. Vilas S. Solanke*; Mr. Naveen Kumar

2016-01-01

This paper presents review on the latest development of control of grid connected photovoltaic energy conversion system. Also this paper present existing systems control algorithm for three-phase and single phase grid-connected photovoltaic (PV) system. This paper focuses on one aspect of solar energy, namely grid interfacing of large-scale PV farms. This Grid-connected photovoltaic i.e. PV systems can provide a number of benefits to electric utilities, such as power loss reduction, improve...

Dynamic analysis of combined photovoltaic source and synchronous generator connected to power grid

Science.gov (United States)

Mahabal, Divya

In the world of expanding economy and technology, the energy demand is likely to increase even with the global efforts of saving and increasing energy efficiency. Higher oil prices, effects of greenhouse gases, and concerns over other environmental impacts gave way to Distributed Generation (DG). With adequate awareness and support, DG's can meet these rising energy demands at lower prices compared to conventional methods. Extensive research is taking place in different areas like fuel cells, photovoltaic cells, wind turbines, and gas turbines. DG's when connected to a grid increase the overall efficiency of the power grid. It is believed that three-fifth of the world's electricity would account for renewable energy by middle of 21st century. This thesis presents the dynamic analysis of a grid connected photovoltaic (PV) system and synchronous generator. A grid is considered as an infinite bus. The photovol-taic system and synchronous generator act as small scale distributed energy resources. The output of the photovoltaic system depends on the light intensity, temperature, and irradiance levels of sun. The maximum power point tracking and DC/AC converter are also modeled for the photovoltaic system. The PV system is connected to the grid through DC/AC system. Different combinations of PV and synchronous generator are modeled with the grid to study the dynamics of the proposed system. The dynamics of the test system is analyzed by subjecting the system to several disturbances under various conditions. All modules are individually modeled and con-nected using MATLAB/Simulink software package. Results from the study show that, as the penetration of renewable energy sources like PV increases into the power system, the dynamics of the system becomes faster. When considering cases such as load switching, PV cannot deliver more power as the performance of PV depends on environmental conditions. Synchronous generator in power system can produce the required amount of

Modeling Of Components Of A Photovoltaic System With Voltage Inverter For Connection To The Electrical Grid

International Nuclear Information System (INIS)

Ferreira, Andreza C.; Blasques, Luis C. M.; Galhardo, Marcos A. B.; Pinho, João T.

2017-01-01

This paper describes the modeling of the electrical equipment and control mechanisms used in the power conditioning system of a grid-connected photovoltaic system (GCPVS), such as the photovoltaic generator, the DC/DC converter, the voltage inverter with PWM control, its output filter, as well as the converter controls and their functionalities, and the interconnection of the system with the distribution grid and load. In addition to the modeling of the grid-tie inverter, the main equipment of the power conditioning system, this paper describes the synchronization form of the photovoltaic (PV) generation with the electricity distribution grid, considering the power injection control method, the maximum power point tracking technique for maximizing the energy supplied by the photovoltaic generator, and the complete topology of the proposed PV system. The main objective is to provide a computational model capable of simulating the behavior of the GCPVS elements, varying the climatic conditions and the power demand on the AC side, presenting consistent results for different operating conditions, such as variations of climatic parameters (solar irradiance, wind speed, and ambient temperature) and load. In these cases, it is possible to evaluate the behavior of the system, sometimes supplying both the active and reactive power of the load, according to the need. (author)

Zero-Voltage Ride-Through Capability of Single-Phase Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Zhen Zhang

2017-03-01

Full Text Available Distributed renewable energy systems play an increasing role in today’s energy paradigm. Thus, intensive research activities have been centered on improving the performance of renewable energy systems, including photovoltaic (PV systems, which should be of multiple-functionality. That is, the PV systems should be more intelligent in the consideration of grid stability, reliability, and fault protection. Therefore, in this paper, the performance of single-phase grid-connected PV systems under an extreme grid fault (i.e., when the grid voltage dips to zero is explored. It has been revealed that combining a fast and accurate synchronization mechanism with appropriate control strategies for the zero-voltage ride-through (ZVRT operation is mandatory. Accordingly, the representative synchronization techniques (i.e., the phase-locked loop (PLL methods in the ZVRT operation are compared in terms of detection precision and dynamic response. It shows that the second-order generalized integrator (SOGI-PLL is a promising solution for single-phase systems in the case of fault ride-through. A control strategy by modifying the SOGI-PLL scheme is then introduced to single-phase grid-connected PV systems for ZVRT operation. Simulations are performed to verify the discussions. The results have demonstrated that the proposed method can help single-phase PV systems to temporarily ride through zero-voltage faults with good dynamics.

Modeling and Simulation for an 8 kW Three-Phase Grid-Connected Photo-Voltaic Power System

OpenAIRE

Cen Zhaohui

2017-01-01

Gird-connected Photo-Voltaic (PV) systems rated as 5-10 kW level have advantages of scalability and energy-saving, so they are very typical for small-scale household solar applications. In this paper, an 8 kW three-phase grid-connected PV system model is proposed and studied. In this high-fidelity model, some basic PV system components such as solar panels, DC-DC converters, DC-AC inverters and three-phase utility grids are mathematically modelled and organized as a complete simulation model....

Experimental evaluation of 8 kW grid-connected photovoltaic system in Egypt

Directory of Open Access Journals (Sweden)

A. Elkholy

2016-09-01

Full Text Available An experimental observation study of 8 kW grid-connected photovoltaic (PV system that is installed at Electronics Research Institute (ERI, Giza, Egypt (Latitude 30.04°N, Longitude 31.21°E, is presented. This study includes the quality of the electrical power generated and injected into the network. The considered system consists of 28 × 295 Wp multicrystalline PV modules, StecaGrid three-phase 8 kW grid-connected inverter and a Solar-Log 300 PM+ for data acquisition and remote monitoring. The power quality parameters at the inverter output side have been measured using CA8335 power quality analyzer. The system has been installed in August 2014 and generated 5.7 MWh till February 2015. The produced electricity by the system is injected directly into the grid without storage device. The purpose of this paper is to present and evaluate the measurements of the power quality parameters obtained from the PV site. Also, this paper presents a comprehensive evaluation of the performance of the system over a period of one week. The observation and analyses exploitation of the collected data can help to evaluate the performance of the PV system connected to the network.

Establishment of key grid-connected performance index system for integrated PV-ES system

Science.gov (United States)

Li, Q.; Yuan, X. D.; Qi, Q.; Liu, H. M.

2016-08-01

In order to further promote integrated optimization operation of distributed new energy/ energy storage/ active load, this paper studies the integrated photovoltaic-energy storage (PV-ES) system which is connected with the distribution network, and analyzes typical structure and configuration selection for integrated PV-ES generation system. By combining practical grid- connected characteristics requirements and technology standard specification of photovoltaic generation system, this paper takes full account of energy storage system, and then proposes several new grid-connected performance indexes such as paralleled current sharing characteristic, parallel response consistency, adjusting characteristic, virtual moment of inertia characteristic, on- grid/off-grid switch characteristic, and so on. A comprehensive and feasible grid-connected performance index system is then established to support grid-connected performance testing on integrated PV-ES system.

A Novel Flying Capacitor Transformerless Inverter for Single-Phase Grid Connected Solar Photovoltaic System

DEFF Research Database (Denmark)

Siwakoti, Yam Prasad; Blaabjerg, Frede

2016-01-01

This paper proposes a new single-phase flying capacitor transformerless PV inverter for grid-connected photovoltaic (PV) systems. The neutral of the grid can be directly connected to the negative terminal of the source (PV). It consists of four power switches, one diode, one capacitor and a small...... and some topologies, which requires two times of the peak ac-voltage magnitude) and, (5) the flying capacitor charges every switching cycle, which reduces the size of the required capacitor with switching frequency. In addition, industry standard half bridge module can be used in the new inverter without...

Model Building of Photovoltaic Array with MPPT Function and Research on Single Phase Grid Connected

OpenAIRE

Li Zhengzhou

2016-01-01

With the continued development of solar photovoltaic technology, research on distributed grid connected photovoltaic system has become a research focus in the field of photovoltaic grid power plant and the computer simulation technology is an effective technology means in the study. On the basis of the photovoltaic array output characteristic equation, the photovoltaic array maximum power control simulation model based on M function is established by using MATLAB/Simulink and the simulation m...

Fuzzy-predictive direct power control implementation of a grid connected photovoltaic system, associated with an active power filter

International Nuclear Information System (INIS)

Ouchen, Sabir; Betka, Achour; Abdeddaim, Sabrina; Menadi, Abdelkrim

2016-01-01

Highlights: • An implementation on dSPACE 1104 of a double stage grid connected photovoltaic system, associated with an active power filter. • A fuzzy logic controller for maximum power point tracking of photovoltaic generator using a boost converter. • Predictive direct power control almost eliminates the effect of harmonics under a unite power factor. • The robustness of control strategies was examined in different irradiance level conditions. - Abstract: The present paper proposes a real time implementation of an optimal operation of a double stage grid connected photovoltaic system, associated with a shunt active power filter. On the photovoltaic side, a fuzzy logic based maximum power point taking control is proposed to track permanently the optimum point through an adequate tuning of a boost converter regardless the solar irradiance variations; whereas, on the grid side, a model predictive direct power control is applied, to ensure both supplying a part of the load demand with the extracted photovoltaic power, and a compensation of undesirable harmonic contents of the grid current, under a unity power factor operation. The implementation of the control strategies is conducted on a small scale photovoltaic system, controlled via a dSPACE 1104 single card. The obtained experimental results show on one hand, that the proposed Fuzzy logic based maximum power taking point technique provides fast and high performances under different irradiance levels while compared with a sliding mode control, and ensures 1.57% more in efficiency. On the other hand, the predictive power control ensures a flexible settlement of active power amounts exchanges with the grid, under a unity power functioning. Furthermore, the grid current presents a sinusoidal shape with a tolerable total harmonic distortion coefficient 4.71%.

Modeling and Simulation for an 8 kW Three-Phase Grid-Connected Photo-Voltaic Power System

Science.gov (United States)

Cen, Zhaohui

2017-09-01

Gird-connected Photo-Voltaic (PV) systems rated as 5-10 kW level have advantages of scalability and energy-saving, so they are very typical for small-scale household solar applications. In this paper, an 8 kW three-phase grid-connected PV system model is proposed and studied. In this high-fidelity model, some basic PV system components such as solar panels, DC-DC converters, DC-AC inverters and three-phase utility grids are mathematically modelled and organized as a complete simulation model. Also, an overall power controller with Maximum Power Point Control (MPPT) is proposed to achieve both high-efficiency for solar energy harvesting and grid-connection stability. Finally, simulation results demonstrate the effectiveness of the PV system model and the proposed controller, and power quality issues are discussed.

Modeling and Simulation for an 8 kW Three-Phase Grid-Connected Photo-Voltaic Power System

Directory of Open Access Journals (Sweden)

Cen Zhaohui

2017-09-01

Full Text Available Gird-connected Photo-Voltaic (PV systems rated as 5-10 kW level have advantages of scalability and energy-saving, so they are very typical for small-scale household solar applications. In this paper, an 8 kW three-phase grid-connected PV system model is proposed and studied. In this high-fidelity model, some basic PV system components such as solar panels, DC-DC converters, DC-AC inverters and three-phase utility grids are mathematically modelled and organized as a complete simulation model. Also, an overall power controller with Maximum Power Point Control (MPPT is proposed to achieve both high-efficiency for solar energy harvesting and grid-connection stability. Finally, simulation results demonstrate the effectiveness of the PV system model and the proposed controller, and power quality issues are discussed.

A techno-economic assessment of grid connected photovoltaic system for hospital building in Malaysia

Science.gov (United States)

Mat Isa, Normazlina; Tan, Chee Wei; Yatim, AHM

2017-07-01

Conventionally, electricity in hospital building are supplied by the utility grid which uses mix fuel including coal and gas. Due to enhancement in renewable technology, many building shall moving forward to install their own PV panel along with the grid to employ the advantages of the renewable energy. This paper present an analysis of grid connected photovoltaic (GCPV) system for hospital building in Malaysia. A discussion is emphasized on the economic analysis based on Levelized Cost of Energy (LCOE) and total Net Present Post (TNPC) in regards with the annual interest rate. The analysis is performed using Hybrid Optimization Model for Electric Renewables (HOMER) software which give optimization and sensitivity analysis result. An optimization result followed by the sensitivity analysis also being discuss in this article thus the impact of the grid connected PV system has be evaluated. In addition, the benefit from Net Metering (NeM) mechanism also discussed.

High Quality Model Predictive Control for Single Phase Grid Connected Photovoltaic Inverters

DEFF Research Database (Denmark)

Zangeneh Bighash, Esmaeil; Sadeghzadeh, Seyed Mohammad; Ebrahimzadeh, Esmaeil

2018-01-01

Single phase grid-connected inverters with LCL filter are widely used to connect the photovoltaic systems to the utility grid. Among the presented control schemes, predictive control methods are faster and more accurate but are more complex to implement. Recently, the model-predictive control...... algorithm for single-phase inverter has been presented, where the algorithm implementation is straightforward. In the proposed approach, all switching states are tested in each switching period to achieve the control objectives. However, since the number of the switching states in single-phase inverter...... is low, the inverter output current has a high total harmonic distortions. In order to reduce the total harmonic distortions of the injected current, this paper presents a high-quality model-predictive control for one of the newest structure of the grid connected photovoltaic inverter, i.e., HERIC...

DISTRIBUTED GRID-CONNECTED PHOTOVOLTAIC POWER SYSTEM EMISSION OFFSET ASSESSMENT: STATISTICAL TEST OF SIMULATED- AND MEASURED-BASED DATA

Science.gov (United States)

This study assessed the pollutant emission offset potential of distributed grid-connected photovoltaic (PV) power systems. Computer-simulated performance results were utilized for 211 PV systems located across the U.S. The PV systems' monthly electrical energy outputs were based ...

Benchmarking of Grid Fault Modes in Single-Phase Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

2013-01-01

Pushed by the booming installations of singlephase photovoltaic (PV) systems, the grid demands regarding the integration of PV systems are expected to be modified. Hence, the future PV systems should become more active with functionalities of Low Voltage Ride-Through (LVRT) and grid support...... phase systems under grid faults. The intent of this paper is to present a benchmarking of grid fault modes that might come in future single-phase PV systems. In order to map future challenges, the relevant synchronization and control strategies are discussed. Some faulty modes are studied experimentally...... and provided at the end of this paper. It is concluded that there are extensive control possibilities in single-phase PV systems under grid faults. The Second Order General Integral based PLL technique might be the most promising candidate for future single-phase PV systems because of its fast adaptive...

Fault Ride-Through of a Grid-connected Photovoltaic System with Quasi Z Source Inverter

DEFF Research Database (Denmark)

Al-Durra, Ahmed; Fayyad, Yara; Muyeen, S.M.

2016-01-01

This article presents fault ride-through schemes for a three-phase quasi Z source single-stage photovoltaic (PV) inverter that is connected to the grid after the distribution network. The quasi Z source inverter employs a unique LC network to couple the inverter main circuit to the input of the PV...... the grid side so that the grid fault ride-through requirements can be fulfilled. Scheme A involves control modification in the system; Schemes B and C involve hardware modification in the circuit topology by adding a chopper circuit across the DC link in Scheme B and across the quasi Z source inverter...

Optimising the economic viability of grid-connected photovoltaic systems

International Nuclear Information System (INIS)

Mondol, Jayanta Deb; Yohanis, Yigzaw G; Norton, Brian

2009-01-01

The impact of photovoltaic (PV) array size, orientation, inclination, load profile, electricity buying price, feed-in tariffs, PV/inverter sizing ratio ('sizing ratio') and PV/inverter cost ratio ('cost ratio') on the economic viability of a grid-connected PV system was investigated using a validated TRNSYS simulation model. The results showed that the fractional load met directly by a PV system depends on matching between PV supply and building load profile, sizing ratio and PV inclination. The profitability of a grid-connected PV system increases if the PV system is sized to reduce excess PV electrical energy fed to the grid when the feed-in tariff is lower than electricity buying price. The effect of feed-in tariffs on PV saving for selected European countries has been shown. The cost of the PV electricity depends on sizing ratio, PV and inverter lifetimes, cost ratio, PV inclination and financial parameters. The effect of cost ratio on the optimum PV/inverter sizing ratio is less significant when the cost ratio lies within 7-11. The minimum PV electricity cost at low and high insolation conditions were obtained for sizing ratios of 1.6 and 1.2, respectively. The lowest PV electricity cost was found for surface slopes within 30-40 for the selected European locations. The PV electricity cost for cost ratio of 5 and 13 varied from 0.44-0.85 EURkWh -1 to 0.38-0.76 EURkWh -1 , respectively within high to low insolation conditions when the PV module unit cost, market discount rate, PV size, PV lifetime and inverter lifetime were assumed to be 6.5 EURW p -1 , 3%, 13 kW p , 20 years and 10 years, respectively. (author)

Real Time Photovoltaic Array Simulator for Testing Grid-Connected PV Inverters

DEFF Research Database (Denmark)

Sera, Dezso; Valentini, Massimo; Raducu, Alin

2008-01-01

In this paper a real time flexible PV array simulator is presented. It is a system that can simulate different PV panel arrays in specific environmental conditions. To evaluate performance of the Maximum Power Point Tracking (MPPT) of grid-connected Photovoltaic (PV) inverters only measurements...... undertaken with an appropriate PV array simulator provide accurate and reproducible results. Thus the PV array simulator has been developed and implemented. MPPT efficiency tests on a commercial grid-connected PV inverter have been performed to validate the PV array simulator....

Grid-connected photovoltaic power systems. Technical and potential problems. A review

International Nuclear Information System (INIS)

Eltawil, Mohamed A.; Zhao, Zhengming

2010-01-01

Traditional electric power systems are designed in large part to utilize large baseload power plants, with limited ability to rapidly ramp output or reduce output below a certain level. The increase in demand variability created by intermittent sources such as photovoltaic (PV) presents new challenges to increase system flexibility. This paper aims to investigate and emphasize the importance of the grid-connected PV system regarding the intermittent nature of renewable generation, and the characterization of PV generation with regard to grid code compliance. The investigation was conducted to critically review the literature on expected potential problems associated with high penetration levels and islanding prevention methods of grid tied PV. According to the survey, PV grid connection inverters have fairly good performance. They have high conversion efficiency and power factor exceeding 90% for wide operating range, while maintaining current harmonics THD less than 5%. Numerous large-scale projects are currently being commissioned, with more planned for the near future. Prices of both PV and balance of system components (BOS) are decreasing which will lead to further increase in use. The technical requirements from the utility power system side need to be satisfied to ensure the safety of the PV installer and the reliability of the utility grid. Identifying the technical requirements for grid interconnection and solving the interconnect problems such as islanding detection, harmonic distortion requirements and electromagnetic interference are therefore very important issues for widespread application of PV systems. The control circuit also provides sufficient control and protection functions like maximum power tracking, inverter current control and power factor control. Reliability, life span and maintenance needs should be certified through the long-term operation of PV system. Further reduction of cost, size and weight is required for more utilization of PV

Control scheme towards enhancing power quality and operational efficiency of single-phase two-stage grid-connected photovoltaic systems

Directory of Open Access Journals (Sweden)

Mahmoud Salem

2015-12-01

Full Text Available Achieving high reliable grid-connected photovoltaic (PV systems with high power quality and high operation efficiency is highly required for distributed generation units. A double grid-frequency voltage ripple is found on the dc-link voltage in single-phase photovoltaic grid-connected systems due to the unbalance of the instantaneous dc input and ac output powers. This voltage ripple has undesirable effects on the power quality and operational efficiency of the whole system. Harmonic distortion in the injected current to the grid is one of the problems caused by this double grid-frequency voltage ripple. The double grid frequency ripple propagates to the PV voltage and current which disturb the extracted maximum power from the PV array. This paper introduces intelligent solutions towards mitigate the side effects of the double grid-frequency voltage ripple on the transferred power quality and the operational efficiency of single-phase two-stage grid-connected PV system. The proposed system has three control loops: MPPT control loop, dc-link voltage control loop and inverter current control loop. Solutions are introduced for all the three control loops in the system. The current controller cancels the dc-link voltage effect on the total harmonic distortion of the output current. The dc-link voltage controller is designed to generate a ripple free reference current signal that leads to enhance the quality of the output power. Also a modified MPPT controller is proposed to optimize the extracted power from the PV array. Simulation results show that higher injected power quality is achieved and higher efficiency of the overall system is realized.

Low Voltage Ride-Through Capability of a Single-Stage Single-Phase Photovoltaic System Connected to the Low-Voltage Grid

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede

2013-01-01

The progressively growing of single-phase photovoltaic (PV) systems makes the Distribution System Operators (DSO) to update or revise the existing grid codes in order to guarantee the availability, quality and reliability of the electrical system. It is expected that the future PV systems connected...... to the low-voltage grid will be more active with functionalities of low voltage ride-through (LVRT) and the grid support capability, which is not the case today. In this paper, the operation principle is demonstrated for a single-phase grid-connected PV system in low voltage ride through operation in order...... to map future challenges. The system is verified by simulations and experiments. Test results show that the proposed power control method is effective and the single-phase PV inverters connected to low-voltage networks are ready to provide grid support and ride-through voltage fault capability...

Fiscal 2000 achievement report. International demonstrative development of photovoltaic power generation system (Demonstrative study on grid-connected photovoltaic power generation system in Thailand); 2000 nendo seika hokokusho. Taiyoko hatsuden system kokusai kyodo jissho kaihatsu - Taiyoko hatsuden keitou renkei system jissho kenkyu (Tai)

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-09-01

A demonstrative study was conducted in Thailand for grasping the effect on small electricity grids when several photovoltaic power generation systems, including AC modules, are connected to the grid. In fiscal 2000, surveys and studies were conducted about the data of the local power system, where to install the demonstrative system, and how to install the same, which were necessary for working out a basic design for Libong Island newly designated as the site for the demonstrative system. It was then concluded that the demonstrative system be a grid-connected 100 kW-level photovoltaic system comprising one main photovoltaic power station (85 kW), photovoltaic power systems for school buildings (3-6 kW, three schools), and AC modules (110 W, 10 locations). The manufacture of solar cell modules, grid-connected power conditioners, and measuring devices were completed. Civil engineering work and construction were under way on the site, including the construction of a management building, installation of concrete bases for solar cell arrays, construction of fences surrounding the site, and so forth. (NEDO)

RMS Current of a Photovoltaic Generator in Grid-Connected PV Systems: Definition and Application

Directory of Open Access Journals (Sweden)

P. J. Pérez

2008-01-01

Full Text Available This paper includes a definition of a new and original concept in the photovoltaic field, RMS current of a photovoltaic generator for grid-connected systems. The RMS current is very useful for calculating energy losses in cables used in a PV generator. As well, a current factor has been defined in order to simplify RMS current calculation. This factor provides an immediate (quick and easy calculation method for the RMS current that does not depend on the case particular conditions (orientation, location, etc.. RMS current and current factor values have been calculated for different locations and modules.

Modeling of Step-up Grid-Connected Photovoltaic Systems for Control Purposes

Directory of Open Access Journals (Sweden)

Daniel Gonzalez

2012-06-01

Full Text Available This paper presents modeling approaches for step-up grid-connected photovoltaic systems intended to provide analytical tools for control design. The first approach is based on a voltage source representation of the bulk capacitor interacting with the grid-connected inverter, which is a common model for large DC buses and closed-loop inverters. The second approach considers the inverter of a double-stage PV system as a Norton equivalent, which is widely accepted for open-loop inverters. In addition, the paper considers both ideal and realistic models for the DC/DC converter that interacts with the PV module, providing four mathematical models to cover a wide range of applications. The models are expressed in state space representation to simplify its use in analysis and control design, and also to be easily implemented in simulation software, e.g., Matlab. The PV system was analyzed to demonstrate the non-minimum phase condition for all the models, which is an important aspect to select the control technique. Moreover, the system observability and controllability were studied to define design criteria. Finally, the analytical results are illustrated by means of detailed simulations, and the paper results are validated in an experimental test bench.

Overview of Grid Codes for Photovoltaic Integration

DEFF Research Database (Denmark)

Zheng, Qianwei; Li, Jiaming; Ai, Xiaomeng

2017-01-01

The increasing grid-connected photovoltaic (PV) power stations might threaten the safety and stability of power system. Therefore, the grid code is developed for PV power stations to ensure the security of PV integrated power systems. In this paper, requirements for PV power integration in differ......The increasing grid-connected photovoltaic (PV) power stations might threaten the safety and stability of power system. Therefore, the grid code is developed for PV power stations to ensure the security of PV integrated power systems. In this paper, requirements for PV power integration...

Sliding-Mode Controller for Maximum Power Point Tracking in Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Paula Andrea Ortiz Valencia

2015-11-01

Full Text Available The maximum power point tracking (MPPT of photovoltaic systems must be as fast and accurate as possible to increase the power production, which eventually increases the PV system profitability. This paper proposes and mathematically analyses a sliding-mode controller to provide a fast and accurate maximum power point tracking in grid-connected photovoltaic systems using a single control stage. This approach avoids the circular dependency in the design of classical cascade controllers used to optimize the photovoltaic system operation, and at the same time, it reduces the number of controllers and avoids the use of linearized models to provide global stability in all the operation range. Such a compact solution also reduces the system cost and implementation complexity. To ensure the stability of the proposed solution, detailed mathematical analyses are performed to demonstrate the fulfillment of the transversality, reachability and equivalent control conditions. Finally, the performance of the proposed solution is validated using detailed simulations, executed in the power electronics simulator PSIM, accounting for both environmental and load perturbations.

Inrush Transient Current Analysis and Suppression of Photovoltaic Grid-Connected Inverters During Voltage Sag

DEFF Research Database (Denmark)

Li, Zhongyu; Zhao, Rende; Xin, Zhen

2016-01-01

The Inrush Transient Current (ITC) in the output of the photovoltaic grid-connected inverters is usually generated when grid voltage sag occurs, which can trigger the protection of the grid-connected inverters, and even destroy the semiconductor switches. Then, the grid-connected inverters...

Economic performance and policies for grid-connected residential solar photovoltaic systems in Brazil

International Nuclear Information System (INIS)

Mitscher, Martin; Rüther, Ricardo

2012-01-01

We analyze the economic competitiveness of grid-connected, distributed solar photovoltaic generation through small-scale rooftop installations in five Brazilian state-capitals. The locations represent a comprehensive set of the two essential parameters for the economic viability of PV—solar irradiation and local electricity tariffs. Levelized electricity costs (LEC) for PV generation and net present values (NPV) for a specific PV system are presented. The analysis comprises three different interest rate scenarios reflecting different conditions for capital acquisition to finance the generators; subsidized, mature market and country-specific risk-adjusted interest. In the NPV analysis, revenue flow is modeled by the sale of PV electricity at current residential tariffs assuming net metering. Using subsidized interest rates, the analysis shows that solar PV electricity is already competitive in Brazil, while in the country-specific risk-adjusted rate, the declining, but still high capital costs of PV make it economically unfeasible. At a mature market interest rate, PV competitiveness is largely dependent on the residential tariff. Economic competitiveness in this scenario is given for locations with high residential tariffs. We demonstrate the high potential of distributed generation with photovoltaic installations in Brazil, and show that under certain conditions, grid-connected PV can be economically competitive in a developing country. - Highlights: ► Debt financed grid-connected PV on Brazilian rooftops can be economically feasible since 2011. ► The cost of capital in Brazil is the decisive parameter in PV competitiveness with conventional generation sources. ► Low-cost, long-term financing is an essential requirement for PV to become an economically justifiable generation alternative. ► The Brazilian market holds huge potential for distributed, residential rooftop PV systems of small size.

Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results.

Science.gov (United States)

Humada, Ali M; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M; Ahmed, Mushtaq N

2016-01-01

A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions.

Model Predictive Control of Grid Connected Modular Multilevel Converter for Integration of Photovoltaic Power Systems

DEFF Research Database (Denmark)

Hajizadeh, Amin; Shahirinia, Amir

2017-01-01

Investigation of an advanced control structure for integration of Photovoltaic Power Systems through Grid Connected-Modular Multilevel Converter (GC-MMC) is proposed in this paper. To achieve this goal, a non-linear model of MMC regarding considering of negative and positive sequence components has...... been presented. Then, due to existence of unbalance voltage faults in distribution grid, non-linarites and uncertainties in model, model predictive controller which is developed for GC-MMC. They are implemented based upon positive and negative components of voltage and current to mitigate the power...

Grid-connected photovoltaic systems for Malaysian residential sector: Effects of component costs, feed-in tariffs, and carbon taxes

International Nuclear Information System (INIS)

Lau, K.Y.; Muhamad, N.A.; Arief, Y.Z.; Tan, C.W.; Yatim, A.H.M.

2016-01-01

Blessed with abundant solar radiation, Malaysia has a huge potential for grid-connected PV (photovoltaic) installations, particularly for its fast-growing residential sector. Nevertheless, Malaysia's PV installation capacity is relatively small compared with the global PV capacity. Significantly, the pricing mechanisms for grid-connected PV projects need to be appropriately assessed to build up the public's confidence to invest in PV projects. In this paper, we analyze the effects of component costs, FiTs (feed-in tariffs), and carbon taxes on grid-connected PV systems in Malaysian residential sector using the HOMER (Hybrid Optimization of Multiple Energy Resources) software. Results demonstrate that the implementation of grid-connected PV systems is highly feasible with PV array costs of $ 1120/kW or lower. For higher PV array costs up to $ 2320/kW, introducing an FiT rate three times higher ($ 0.30/kWh) than the grid tariff for a 100 kW grid sale capacity will, NPC-wise, prioritize grid-connected PV systems over the utility grid. By implementing the FiT ($ 0.50/kWh) and the carbon tax ($ 36/metric ton) schemes simultaneously, grid-connected PV systems will remain as the optimal systems even for costly PV arrays (up to $ 4000/kW). The findings are of paramount importance as far as PV pricing variability is concerned. - Highlights: • Grid-connected PV for Malaysian residential sector has been analyzed using HOMER. • Component costs, feed-in tariffs, and carbon taxes affect optimal system types. • Grid-connected PV projects are feasible for low PV array costs ($ 1120/kW or lower). • For higher PV array and inverter costs, feed-in tariffs should be implemented. • Combining feed-in tariffs with carbon taxes are effective for further lowering NPCs.

Predicting the behavior of a grid-connected photovoltaic system from measurements of solar radiation and ambient temperature

International Nuclear Information System (INIS)

Hernandez, J.; Gordillo, G.; Vallejo, W.

2013-01-01

Highlights: ► A model to predict in a reliable way the behavior of a GCPV system is presented. ► Radiation and temperature behavior were shaped with probability density functions. ► This probability density functions were made from real measurements. ► This model was verified for comparing their behavior with real measurements. ► It can be used in any electrical systems language which have programming routines. - Abstract: This paper presents a methodology to predict in a statistically reliable way the behavior of a grid-connected photovoltaic system. The methodology developed can be implemented either in common programming software or through an off-the-shelf simulation of electrical systems. Initially, the atmospheric parameters that influence the behavior of PV generators (radiation and temperature) are characterized in a probabilistic manner. In parallel, a model compound by various PV generator components is defined: the modules (and their electrical and physical characteristics), their connection to form the generator, and the inverter type. This model was verified for comparing their behavior with output measured on a real installed system of 3.6 kWp. The solar resource characterized and the photovoltaic system model are integrated in a non-deterministic approach using the stochastic Monte Carlo method, developed in the programming language DPL of the electrical-systems simulation software DIGSILENT®. It is done to estimate the steady-state electrical parameters describing the influence of the grid-connected photovoltaic system. Specifically, we estimated the nominal peak power of the PV generator to minimize network losses, subject to constraints on nodes voltages and conductor currents

A Combined Two-Method MPPT Control Scheme for Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Dorofte, Christinel; Borup, Uffe; Blaabjerg, Frede

2005-01-01

In order to increase the output efficiency of a grid-connected photovoltaic (PV) system it is important to have an efficient Maximum Power Point Tracker (MPPT). In the case of low irradiation, the Perturb and Observe (PO) and Incremental Conductance (IC) methods have a poor efficiency, because...... of the poor resolution in the acquired signals, when a fixed point implementation is done. A cost-effective two-method MPPT control scheme is proposed in this paper to track the maximum power point (MPP) at both low and high irradiation, by combining a Constant Voltage (CV) method and modified PO algorithm...

Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results

Science.gov (United States)

Humada, Ali M.; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M.; Ahmed, Mushtaq N.

2016-01-01

A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions. PMID:27035575

Improvement of the grid-connect current quality using novel proportional-integral controller for photovoltaic inverters.

Science.gov (United States)

Cheng, Yuhua; Chen, Kai; Bai, Libing; Yang, Jing

2014-02-01

Precise control of the grid-connected current is a challenge in photovoltaic inverter research. Traditional Proportional-Integral (PI) control technology cannot eliminate steady-state error when tracking the sinusoidal signal from the grid, which results in a very high total harmonic distortion in the grid-connected current. A novel PI controller has been developed in this paper, in which the sinusoidal wave is discretized into an N-step input signal that is decided by the control frequency to eliminate the steady state error of the system. The effect of periodical error caused by the dead zone of the power switch and conduction voltage drop can be avoided; the current tracking accuracy and current harmonic content can also be improved. Based on the proposed PI controller, a 700 W photovoltaic grid-connected inverter is developed and validated. The improvement has been demonstrated through experimental results.

Implementation of fuzzy-sliding mode based control of a grid connected photovoltaic system.

Science.gov (United States)

Menadi, Abdelkrim; Abdeddaim, Sabrina; Ghamri, Ahmed; Betka, Achour

2015-09-01

The present work describes an optimal operation of a small scale photovoltaic system connected to a micro-grid, based on both sliding mode and fuzzy logic control. Real time implementation is done through a dSPACE 1104 single board, controlling a boost chopper on the PV array side and a voltage source inverter (VSI) on the grid side. The sliding mode controller tracks permanently the maximum power of the PV array regardless of atmospheric condition variations, while The fuzzy logic controller (FLC) regulates the DC-link voltage, and ensures via current control of the VSI a quasi-total transit of the extracted PV power to the grid under a unity power factor operation. Simulation results, carried out via Matlab-Simulink package were approved through experiment, showing the effectiveness of the proposed control techniques. Copyright © 2015. Published by Elsevier Ltd.

Comparative Analysis of Inversors for Small PV Systems Grid Connected

International Nuclear Information System (INIS)

Sidrach de Cardona, M.; Ramirez, L.

2001-01-01

The energy produced by a grid connected photovoltaic system is a function of weather conditions, mainly available radiation and temperature, photovoltaic array efficiency and inverter characteristics. The results obtained in experimental measurements with four small grid-connected inverters are described in this work. The main goal is to know the inverter performance in real operation conditions. For this purpose a 2 kW photovoltaic system has been used. These results allow us to know both the inverter efficiency and its output power quality. The following parameters have been evaluated as a function of output inverter power: efficiency, point of maximum power tracking, intensity and voltage waveform, total harmonic distortion and harmonic values to 31 order, frequency, power factor and reactive power. Other interesting parameters like stand-by energy consumption and daily losses due to the inverter threshold have also been analyzed. The results allow us to know the inverter features as a function of its real work point. In our comparative study it is possible to observe remarkable differences between the inverters; these results show how important it is to have a unique standard for inverters to photovoltaic grid-connected systems. (Author) 10 refs

Task 5. Grid interconnection of building integrated and other dispersed photovoltaic power systems. Grid-connected photovoltaic power systems: power value and capacity value of PV systems

Energy Technology Data Exchange (ETDEWEB)

Groppi, F.

2002-02-15

This report for the International Energy Agency (IEA) made by Task 5 of the Photovoltaic Power Systems (PVPS) programme takes a look at the power value and capacity value of photovoltaic power systems. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. Task 5 deals with issues concerning grid-interconnection and dispersed PV power systems. This report summarises the results of a study aimed to assess the benefits that may be obtained when distributed PV production systems are present in a low-voltage grid. The basic aspects concerning the power-value and those related to the capacity-value are discussed. Data obtained from simulations are presented and discussed. A simple concept shows that great variation occurs if varying load patterns are taken into account. The power-value of PV generation in the grid varies instant by instant depending on the current level of power production and on the surrounding load conditions. Although the three case-studies considered do not cover all the possibilities of coupling between PV and loads, the results obtained show a good differentiation among users with PV production which leads to interesting conclusions.

A technical, economic, and environmental performance of grid-connected hybrid (photovoltaic-wind) power system in Algeria.

Science.gov (United States)

Saheb-Koussa, Djohra; Koussa, Mustapha; Said, Nourredine

2013-01-01

This paper studies the technical, economic, and environmental analysis of wind and photovoltaic power systems connected to a conventional grid. The main interest in such systems is on-site consumption of the produced energy, system hybridization, pooling of resources, and contribution to the environment protection. To ensure a better management of system energy, models have been used for determining the power that the constituting subsystems can deliver under specific weather conditions. Simulation is performed using MATLAB-SIMULINK. While, the economic and environmental study is performed using HOMER software. From an economic point of view, this allows to compare the financial constraints on each part of the system for the case of Adrar site which is located to the northern part of the south of Algeria. It also permits to optimally size and select the system presenting the best features on the basis of two parameters, that is, cost and effectiveness. From an environmental point of view, this study allows highlighting the role of renewable energy in reducing gas emissions related to greenhouse effects. In addition, through a set of sensitivity analysis, it is found that the wind speed has more effects on the environmental and economic performances of grid-connected hybrid (photovoltaic-wind) power systems.

A Technical, Economic, and Environmental Performance of Grid-Connected Hybrid (Photovoltaic-Wind Power System in Algeria

Directory of Open Access Journals (Sweden)

Djohra Saheb-Koussa

2013-01-01

Full Text Available This paper studies the technical, economic, and environmental analysis of wind and photovoltaic power systems connected to a conventional grid. The main interest in such systems is on-site consumption of the produced energy, system hybridization, pooling of resources, and contribution to the environment protection. To ensure a better management of system energy, models have been used for determining the power that the constituting subsystems can deliver under specific weather conditions. Simulation is performed using MATLAB-SIMULINK. While, the economic and environmental study is performed using HOMER software. From an economic point of view, this allows to compare the financial constraints on each part of the system for the case of Adrar site which is located to the northern part of the south of Algeria. It also permits to optimally size and select the system presenting the best features on the basis of two parameters, that is, cost and effectiveness. From an environmental point of view, this study allows highlighting the role of renewable energy in reducing gas emissions related to greenhouse effects. In addition, through a set of sensitivity analysis, it is found that the wind speed has more effects on the environmental and economic performances of grid-connected hybrid (photovoltaic-wind power systems.

Optimal system sizing in grid-connected photovoltaic applications

Science.gov (United States)

Simoens, H. M.; Baert, D. H.; de Mey, G.

A costs/benefits analysis for optimizing the combination of photovoltaic (PV) panels, batteries and an inverter for grid interconnected systems at a 500 W/day Belgian residence is presented. It is assumed that some power purchases from the grid will always be necessary, and that excess PV power can be fed into the grid. A minimal value for the cost divided by the performance is defined for economic optimization. Shortages and excesses are calculated for PV panels of 0.5-10 kWp output, with consideration given to the advantages of a battery back-up. The minimal economic value is found to increase with the magnitude of PV output, and an inverter should never be rated at more than half the array maximum output. A maximum panel size for the Belgian residence is projected to be 6 kWp.

A Technical, Economic, and Environmental Performance of Grid-Connected Hybrid (Photovoltaic-Wind) Power System in Algeria

OpenAIRE

Saheb-Koussa, Djohra; Koussa, Mustapha; Said, Nourredine

2013-01-01

This paper studies the technical, economic, and environmental analysis of wind and photovoltaic power systems connected to a conventional grid. The main interest in such systems is on-site consumption of the produced energy, system hybridization, pooling of resources, and contribution to the environment protection. To ensure a better management of system energy, models have been used for determining the power that the constituting subsystems can deliver under specific weather conditions. Simu...

Grid-Tied Photovoltaic Power System

Science.gov (United States)

Eichenberg, Dennis J.

2011-01-01

A grid-tied photovoltaic (PV) power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. Operating costs of a PV power system are low compared to conventional power technologies. This method can displace the highest-cost electricity during times of peak demand in most climatic regions, and thus reduce grid loading. Net metering is often used, in which independent power producers such as PV power systems are connected to the utility grid via the customers main service panels and meters. When the PV power system is generating more power than required at that location, the excess power is provided to the utility grid. The customer pays the net of the power purchased when the on-site power demand is greater than the onsite power production, and the excess power is returned to the utility grid. Power generated by the PV system reduces utility demand, and the surplus power aids the community. Modern PV panels are readily available, reliable, efficient, and economical, with a life expectancy of at least 25 years. Modern electronics have been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy equal to the modern PV panels. The grid-tied PV power system was successfully designed and developed, and this served to validate the basic principles developed, and the theoretical work that was performed. Grid-tied PV power systems are reliable, maintenance- free, long-life power systems, and are of significant value to NASA and the community. Of particular value are the analytical tools and capabilities that have been successfully developed. Performance predictions can be made confidently for grid-tied PV systems of various scales. The work was done under the NASA Hybrid Power Management (HPM

Grid Converters for Photovoltaic and Wind Power Systems

DEFF Research Database (Denmark)

Teodorescu, Remus; Liserre, Marco; Rodriguez, Pedro

power, operation within a wide range of voltage and frequency, voltage ride-through capability, reactive current injection during faults, grid services support. This book explains the topologies, modulation and control of grid converters for both photovoltaic and wind power applications. In addition...... to power electronics, this book focuses on the specific applications in photovoltaic wind power systems where grid condition is an essential factor. With a review of the most recent grid requirements for photovoltaic and wind power systems, the book discusses these other relevant issues: Modern grid...... inverter topologies for photovoltaic and wind turbines Islanding detection methods for photovoltaic systems Synchronization techniques based on second order generalized integrators (SOGI) Advanced synchronization techniques with robust operation under grid unbalance condition grid filter design and active...

Review international standards for grid connected photovoltaic systems in Malaysia

International Nuclear Information System (INIS)

Mekhilef, S.; Rahim, N.A.

2006-01-01

Grid connected PV is being applied on variety application including large centralised stations, commercial building and individual houses. There is a need for specific standard to address distinctive new issue created by grid connected PV power system. Internationally many countries are attempting to develop standards for building integration, Dc side issues and grid connection issues. This paper surveys the current development state of the major countries standards in this area, comparing and contrasting, standards and guideline under development, also addressing the need of standards for grid connected in Malaysia

Passive P-control of a grid-connected photovoltaic inverter

NARCIS (Netherlands)

Meza, C.; Jeltsema, D.; Scherpen, J. M. A.; Biel, D.

2008-01-01

A passive P-controller for a single-phase single-stage grid-connected photovoltaic inverter is presented. Explicit dependance of the PV array parameters on external unpredictable variables such as temperature and solar irradiance is avoided by extending the control scheme with a reference estimator.

Output-Feedback Nonlinear Adaptive Control Strategy of the Single-Phase Grid-Connected Photovoltaic System

Directory of Open Access Journals (Sweden)

Abdelmajid Abouloifa

2018-01-01

Full Text Available This paper addresses the problem of controlling the single-phase grid connected to the photovoltaic system through a full bridge inverter with LCL-filter. The control aims are threefold: (i imposing the voltage in the output of PV panel to track a reference provided by the MPPT block; (ii regulating the DC-link voltage to guarantee the power exchange between the source and AC grid; (iii ensuring a satisfactory power factor correction (PFC. The problem is dealt with using a cascade nonlinear adaptive controller that is developed making use of sliding-mode technique and observers in order to estimate the state variables and grid parameters, by measuring only the grid current, PV voltage, and the DC bus voltage. The control problem addressed by this work involves several difficulties, including the uncertainty of some parameters of the system and the numerous state variables are inaccessible to measurements. The results are confirmed by simulation under MATLAB∖Simulink∖SimPowerSystems, which show that the proposed regulator is robust with respect to climate changes.

Hybrid system power generation'wind-photovoltaic' connected to the ...

African Journals Online (AJOL)

Hybrid system power generation'wind-photovoltaic' connected to the ... from Hybrid System, power delivered to or from grid and phase voltage of the inverter leg. ... Renewable Energy, Electrical Network 220 kV, Hybrid System, Solar, MPPT.

Considerations on the modeling of photovoltaic systems for grid impact studies

NARCIS (Netherlands)

Cuk, V.; Ribeiro, P.F.; Cobben, J.F.G.; Kling, W.L.; Isleifsson, F.R.; Bindner, H.W.; Martensen, N.; Samadi, A.; Söder, L.

2011-01-01

Photovoltaic systems continue to be deployed at increasing levels and their impact on the electric grid needs to be evaluated more accurately. This includes the impact both in the local grid where they are connected and the impact on the operation of the whole system. As a consequence, adequate

Energy efficiency design strategies for buildings with grid-connected photovoltaic systems

Science.gov (United States)

Yimprayoon, Chanikarn

The building sector in the United States represents more than 40% of the nation's energy consumption. Energy efficiency design strategies and renewable energy are keys to reduce building energy demand. Grid-connected photovoltaic (PV) systems installed on buildings have been the fastest growing market in the PV industry. This growth poses challenges for buildings qualified to serve in this market sector. Electricity produced from solar energy is intermittent. Matching building electricity demand with PV output can increase PV system efficiency. Through experimental methods and case studies, computer simulations were used to investigate the priorities of energy efficiency design strategies that decreased electricity demand while producing load profiles matching with unique output profiles from PV. Three building types (residential, commercial, and industrial) of varying sizes and use patterns located in 16 climate zones were modeled according to ASHRAE 90.1 requirements. Buildings were analyzed individually and as a group. Complying with ASHRAE energy standards can reduce annual electricity consumption at least 13%. With energy efficiency design strategies, the reduction could reach up to 65%, making it possible for PV systems to meet reduced demands in residential and industrial buildings. The peak electricity demand reduction could be up to 71% with integration of strategies and PV. Reducing lighting power density was the best single strategy with high overall performances. Combined strategies such as zero energy building are also recommended. Electricity consumption reductions are the sum of the reductions from strategies and PV output. However, peak electricity reductions were less than their sum because they reduced peak at different times. The potential of grid stress reduction is significant. Investment incentives from government and utilities are necessary. The PV system sizes on net metering interconnection should not be limited by legislation existing in

Factors that can influence the economic feasibility of stand-alone and grid-connected photovoltaic systems: case studies using the software AVES-F

International Nuclear Information System (INIS)

Blasques, L.C.M.; Pinho, J.T.

2004-01-01

This paper presents case studies of economic feasibility of solar photovoltaic systems using the software AVES-F (Analysis of Economic Feasibility of Photovoltaic Systems), developed by the authors, considering cases of stand-alone and grid-connected systems. The software takes into account several factors that can influence the economic feasibility of these kind of systems, like load to be supplied, distance to the grid, the use regime of the system, applied subsidies and others. The main goal of this paper is to analyze some of these factors and to observe how they can affect the economics of PV systems for electricity generation. (authors)

Values and potentials of grid-connected solar photovoltaic applications in Malaysia

International Nuclear Information System (INIS)

Ahmad Hadri Haris; Iszuan Shah Syed Ismail

2006-01-01

Since early 1998, TNB Research Sdn Bhd has been conducting a pilot project to evaluate the performance and economics of grid-connected solar photovoltaic (PV) applications in Malaysia. The project is co-funded by Tenaga Nasional Berhad (TNB) and Malaysia Electricity Supply Industry Trust Account (MESITA). Currently, research project is being concluded with many valuable findings that would be able to provide the direction for the next solar PV development in Malaysia. In total, six pilot grid-connected solar PV systems were installed, where five are located within Klang Valley area and one in Port Dickson. The systems installation and commissioning were staggered between August 1998 to November 2001. A variety of building type was also selected for the system installation. In addition, various PV systems technologies and configurations were applied with average PV power capacity of 3 kW. These variances provide a good opportunity to assess the actual performances and economics of the solar PV applications under the Malaysian environment. This paper would discuss some of the findings, but with a focus on the values and potentials of the grid-connected solar PV applications in Malaysia

A Single-Phase Voltage-Controlled Grid-Connected Photovoltaic System With Power Quality Conditioner Functionality

DEFF Research Database (Denmark)

Kerekes, Tamas; Liserre, Marco; Mastromauro, R. A.

2009-01-01

Future ancillary services provided by photovoltaic (PV) systems could facilitate their penetration in power systems. Also low power PV systems can be designed to improve the power quality. This paper presents a single-phase photovoltaic system that provides grid voltage support and compensation o...

Three-level grid-connected photovoltaic inverter with maximum power point tracking

International Nuclear Information System (INIS)

Tsang, K.M.; Chan, W.L.

2013-01-01

Highlight: ► This paper reports a novel 3-level grid connected photovoltaic inverter. ► The inverter features maximum power point tracking and grid current shaping. ► The inverter can be acted as an active filter and a renewable power source. - Abstract: This paper presents a systematic way of designing control scheme for a grid-connected photovoltaic (PV) inverter featuring maximum power point tracking (MPPT) and grid current shaping. Unlike conventional design, only four power switches are required to achieve three output levels and it is not necessary to use any phase-locked-loop circuitry. For the proposed scheme, a simple integral controller has been designed for the tracking of the maximum power point of a PV array based on an improved extremum seeking control method. For the grid-connected inverter, a current loop controller and a voltage loop controller have been designed. The current loop controller is designed to shape the inverter output current while the voltage loop controller can maintain the capacitor voltage at a certain level and provide a reference inverter output current for the PV inverter without affecting the maximum power point of the PV array. Experimental results are included to demonstrate the effectiveness of the tracking and control scheme.

A Novel Model Predictive Control for Single-Phase Grid-Connected Photovoltaic Inverters

DEFF Research Database (Denmark)

Zangeneh Bighash, Esmaeil; Sadeghzadeh, Seyed Mohammad; Ebrahimzadeh, Esmaeil

2017-01-01

Single-phase grid-connected inverters with LCL filter are widely used to connect photovoltaic systems to the utility grid. Among the existing control schemes, predictive control methods are faster and more accurate but also more complicated to implement. Recently, the Model Predictive Control (MPC......) algorithm for single-phase inverter has been presented, where the algorithm implementation is straightforward. In the MPC approach, all switching states are considered in each switching period to achieve the control objectives. However, since the number of switching states in single-phase inverters is small......, the inverter output current has a high Total Harmonic Distortions (THD). In order to reduce this, this paper presents an improved MPC for single-phase grid-connected inverters. In the proposed approach, the switching algorithm is changed and the number of the switching states is increased by means of virtual...

A review of single-phase grid-connected inverters for photovoltaic modules

DEFF Research Database (Denmark)

Kjaer, Soren Baekhoej; Pedersen, John Kim; Blaabjerg, Frede

2005-01-01

-phase grid; 3) whether they utilizes a transformer (either line or high frequency) or not; and 4) the type of grid-connected power stage. Various inverter topologies are presented, compared, and evaluated against demands, lifetime, component ratings, and cost. Finally, some of the topologies are pointed out......This review focuses on inverter technologies for connecting photovoltaic (PV) modules to a single-phase grid. The inverters are categorized into four classifications: 1) the number of power processing stages in cascade; 2) the type of power decoupling between the PV module(s) and the single...

Study of electrical and thermal characteristics of inverters for grid-connected photovoltaic systems; Estudo de caracteristicas eletricas e termicas de inversores para sistemas fotovoltaicos conectados a rede

Energy Technology Data Exchange (ETDEWEB)

Rampinelli, Giuliano Arns

2010-12-15

Grid-connected photovoltaic systems directly convert solar energy into electrical energy delivering to the distribution grid a clean and renewable energy. These systems are basically formed by an array of photovoltaic modules and inverters. The inverters are responsible for converting direct current to alternating current. A study of electrical and thermal characteristics of inverters used in grid-connected photovoltaic systems from a theoretical and experimental analysis. The inverters tests were carried out in two stages: the first stage was performed at Solar Energy Lab. of the Federal University of Rio Grande do Sul (UFRGS), Brazil, where it was used a 4,8 kW{sub p} grid-connected photovoltaic system and ten inverters of different manufacturers. The inverters electrical characteristics measured and analyzed were: direct current to alternating current conversion efficiency, maximum power point tracker efficiency, power factor and harmonic distortion in current and voltage. Inverters thermal testing was also conducted and its results are presented ana analyzed. The second stage of the experimental tests was performed at Photovoltaic Solar Energy Lab. at CIEMAT in Spain. It was used 3 kW{sub p} photovoltaic system and seven inverters of different manufacturers. The inverters are single-phase, up to 5 kW and different topologies (high frequency transformer, low frequency transformer and transformerless). The influence of DC voltage input in the behavior of DC to AC conversion efficiency and power factor was analyzed. The results of the tests allowed the development of mathematical models that describe the electrical and thermal behavior of the inverters. The proposed mathematical models were inserted into computer simulation software developed at UFRGS named FVConect. The evolution of the simulation results compared to the experimental results validates the proposed models. The analysis of the behavior of the inverters improves the understanding of the operating os

Regulatory potential for increasing small scale grid connected photovoltaic (PV) deployment in Australia

International Nuclear Information System (INIS)

Sivaraman, Deepak; Horne, Ralph E.

2011-01-01

The last decade has seen significant innovation and change in regulatory incentives to support photovoltaic deployment globally. With high fossil fuel dependency and abundant solar resource availability in Australia, grid connected photovoltaics are a viable low carbon technology option in existing electricity grids. Drawing on international examples, the potential to increase grid PV deployment through government response and regulation is explored. For each renewable energy certificate (REC) earned by small scale photovoltaics until 2012, the market provides four additional certificates under the current banded renewable targets. Our analysis indicates that REC eligibility is not accurately estimated currently, and an energy model is developed to calculate the variance. The energy model estimates as much as 26% additional REC's to be obtained by a 3 kWp PV system, when compared to the currently used regulatory method. Moreover, the provision of REC's increases benefits to PV technologies, in the process distorting CO 2 abatement (0.21 tonne/REC) by 68%, when PV displaces peaking natural gas plants. Consideration of the secondary effects of a banded structure on emissions trading market is important in the context of designing a range of initiatives intended to support a transition to a low carbon electricity sector. - Research Highlights: →Grid connected photovoltaics hedge spikes in peak demand summer electricity prices. →Nationwide feed in tariff and new building regulations needed to increase PV deployment. →Australia has transitioned from a solar rebate to a banded solar credit structure. →The currently used regulatory deeming method underestimates REC eligibility by 27%. →The banded structure can potentially distort CO 2 abatement by as much as 68%.

Lightning Surge Analysis on a Large Scale Grid-Connected Solar Photovoltaic System

Directory of Open Access Journals (Sweden)

Nur Hazirah Zaini

2017-12-01

Full Text Available Solar photovoltaic (PV farms currently play a vital role in the generation of electrical power in different countries, such as Malaysia, which is moving toward the use of renewable energy. Malaysia is one of the countries with abundant sunlight and thus can use solar PV farms as alternative sources for electricity generation. However, lightning strikes frequently occur in the country. Being installed in open and flat areas, solar PV farms, especially their electronic components, are at great risk of damage caused by lightning. In this paper, the effects of lightning currents with different peak currents and waveshapes on grid-connected solar PV farms were determined to approximate the level of transient effect that can damage solar PV modules, inverters and transformers. Depending on the location of the solar PV farm, engineer can obtain information on the peak current and median current of the site from the lightning location system (LLS and utilise the results obtained in this study to appropriately assign an SPD to protect the solar panel, inverter and the main panel that connected to the grid. Therefore, the simulation results serve as the basis for controlling the effects of lightning strikes on electrical equipment and power grids where it provides proper justification on the ‘where to be installed’ and ‘what is the rating’ of the SPD. This judgment and decision will surely reduce the expensive cost of repair and replacement of electrical equipment damages due to the lightning.

Benchmarking of Phase Locked Loop based Synchronization Techniques for Grid-Connected Inverter Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Hadjidemetriou, Lenos; Blaabjerg, Frede

2015-01-01

Grid-connected renewables are increasingly developed in recent years, e.g. wind turbine systems and photovoltaic systems. Synchronization of the injected current with the grid is mandatory. However, grid disturbances like voltage sags, harmonics, and frequency deviations may occur during operatio...

Profitability analysis of grid-connected photovoltaic facilities for household electricity self-sufficiency

International Nuclear Information System (INIS)

Colmenar-Santos, Antonio; Campíñez-Romero, Severo; Pérez-Molina, Clara; Castro-Gil, Manuel

2012-01-01

Spain exhibits a high level of energy dependence and has significant solar energy resources. These two facts have given rise to the prominence that renewable energy, particularly solar photovoltaic technology, has enjoyed in recent years, supported by a favorable regulatory framework. Currently, the Spanish Government is providing new ways in energy policy to enhance and accelerate the development of low-power photovoltaic generation facilities for self-consumption by introducing energy policies for feed-in payments of surplus electricity. Such facilities are an example of distributed electrical generation with important benefits for the environment and the rest of the electrical system because, when properly managed, they can help improve the system’s stability and reduce overall losses. By analyzing household demand and solar photovoltaic energy resources, the profitability of such facilities is considered in this article, taking into account the technical and economic impact of storage systems and proposing models for feed-in payments of surplus electricity, in an attempt to assess whether this method of electricity generation versus the method of conventionally supplied power from a grid at a regulated tariff can rival each other economically, in terms of parity. - Highlight: ► The use of grid-connected photovoltaic facilities for household electricity self-sufficiency is presented. ► The need for legal frameworks that include retributive mechanisms for the surplus energy is pointed out. ► Two models are proposed for the remuneration of surplus energy generated. ► Models show economic profitability without feed-in-tariff or compensations. ► Facilities described offer ancillary services for grid stability and smart-grid integration.

Policy incentives and grid-connected photovoltaics system development in China

Energy Technology Data Exchange (ETDEWEB)

Wang Jing; Xu Yugao

2007-07-01

China has made considerable progress in solar PV generation technology. However, compared with conventional generation technologies or even other renewables such as wind and biomass, grid-connected PV technology is in its early stage and has not reached an adequate level of economic performance. Therefore, policy incentives will play important roles in attracting more social investments to facilitate the development of grid-connected PV generation. This paper is focused on analyzing the role of incentive policies in enhancing the market competitiveness of grid-connected solar PV systems in the context of China with an economic model and some policy suggestions are given based on simulation modeling efforts. (auth)

Evaluation of a Distributed Photovoltaic System in Grid-Connected and Standalone Applications by Different MPPT Algorithms

Directory of Open Access Journals (Sweden)

Ru-Min Chao

2018-06-01

Full Text Available Due to the shortage of fossil fuel and the environmental pollution problem, solar energy applications have drawn a lot of attention worldwide. This paper reports the use of the latest patented distributed photovoltaic (PV power system design, including the two possible maximum power point tracking (MPPT algorithms, a power optimizer, and a PV power controller, in grid-connected and standalone applications. A distributed PV system with four amorphous silicon thin-film solar panels is used to evaluate both the quadratic maximization (QM and the Steepest descent (SD MPPT algorithms. The system’s design is different for the QM or the SD MPPT algorithm being used. The test result for the grid-connected silicon-based PV panels will also be reported. Considering the settling time for the power optimizer to be 20 ms, the test result shows that the tracking time for the QM method is close to 200 ms, which is faster when compared with the SD method whose tracking time is 500 ms. Besides this, the use of the QM method provides a more stable power output since the tracking is restricted by a local power optimizer rather than the global tracking the SD method uses. For a standalone PV application, a solar-powered boat design with 18 PV panels using a cascaded MPPT controller is introduced, and it provides flexibility in system design and the effective use of photovoltaic energy.

The research of SSR which can be restrained by photovoltaic grid connected

Science.gov (United States)

Li, Kuan; Liu, Meng; Zheng, Wei; Li, Yudun; Wang, Xin

2018-02-01

Utilization of photovoltaic power generation has attracted considerable attention, and it is growing rapidly due to its environmental benefits. The series capacitive compensation is needed to be introduced into the lines which could improve the transmission capacity. However, the series capacitive compensation may lead to sub-synchronous resonance(SSR). This paper proposes a method to restrain the SSR based on photovoltaic grid connected which is caused by series capacitive compensation. Sub-synchronous oscillation damping controller (SSDC) is designed based on complex torque coefficient approach, and the SSDC is added to the PV power station’s main controller to damp SSR. IEEE Second benchmark model is used as simulation model based on PSCAD/EMTDC. The results show that the designed SSDC could restrain SSR and improve stability in PV grid connected effectively.

Optimal sizing of a hybrid grid-connected photovoltaic and wind power system

International Nuclear Information System (INIS)

González, Arnau; Riba, Jordi-Roger; Rius, Antoni; Puig, Rita

2015-01-01

Highlights: • Hybrid renewable energy systems are efficient mechanisms to generate electrical power. • This work optimally sizes hybrid grid-connected photovoltaic–wind power systems. • It deals with hourly wind, solar irradiation and electricity demand data. • The system cost is minimized while matching the electricity supply with the demand. • A sensitivity analysis to detect the most critical design variables has been done. - Abstract: Hybrid renewable energy systems (HRES) have been widely identified as an efficient mechanism to generate electrical power based on renewable energy sources (RES). This kind of energy generation systems are based on the combination of one or more RES allowing to complement the weaknesses of one with strengths of another and, therefore, reducing installation costs with an optimized installation. To do so, optimization methodologies are a trendy mechanism because they allow attaining optimal solutions given a certain set of input parameters and variables. This work is focused on the optimal sizing of hybrid grid-connected photovoltaic–wind power systems from real hourly wind and solar irradiation data and electricity demand from a certain location. The proposed methodology is capable of finding the sizing that leads to a minimum life cycle cost of the system while matching the electricity supply with the local demand. In the present article, the methodology is tested by means of a case study in which the actual hourly electricity retail and market prices have been implemented to obtain realistic estimations of life cycle costs and benefits. A sensitivity analysis that allows detecting to which variables the system is more sensitive has also been performed. Results presented show that the model responds well to changes in the input parameters and variables while providing trustworthy sizing solutions. According to these results, a grid-connected HRES consisting of photovoltaic (PV) and wind power technologies would be

Development of a software application to evaluate the performance and energy losses of grid-connected photovoltaic systems

International Nuclear Information System (INIS)

Trillo-Montero, D.; Santiago, I.; Luna-Rodriguez, J.J.; Real-Calvo, R.

2014-01-01

Highlights: • Software application to perform an automated analysis of grid-connected PV systems. • It integrates data from all devices registering data on typical PV installations. • Flexible to analyze installations with different configurations and components. • An analysis of two grid-connected PV systems located in Andalusia, was performed. • Temperature losses in summer months varying between 15% and 25% of energy production. - Abstract: The aim of this paper was to design and develop a software application that enables users to perform an automated analysis of data from the monitoring of grid-connected photovoltaic (PV) systems. This application integrates data from all devices already in operation such as environmental sensors, inverters and meters, which record information on typical PV installations. This required the development of a Relational Database Management System (RDBMS), consisting of a series of linked databases, enabling all PV system information to be stored; and a software, called S·lar, which enables all information from the monitoring to be automatically migrated to the database as well as determining some standard magnitudes related to performances and losses of PV installation components at different time scales. A visualization tool, which is both graphical and numerical, makes access to all of the information be a simple task. Moreover, the application enables relationships between parameters and/or magnitudes to be easily established. Furthermore, it can perform a preliminary analysis of the influence of PV installations on the distribution grids where the produced electricity is injected. The operation of such a software application was implemented by performing the analysis of two grid-connected PV installations located in Andalusia, Spain, via data monitoring therein. The monitoring took place from January 2011 to May 2012

Storage systems for improved grid integration of photovoltaic systems; Speichersysteme fuer eine verbesserte Netzintegration von Photovoltaikanlagen

Energy Technology Data Exchange (ETDEWEB)

Ying, Shaoqing [Brandenburgische Technische Univ. Cottbus (Germany). CEBra-Research

2013-07-15

Since the enactment of the Renewable Energy Law in the year 2000 Germany has seen a massive increase in capacity for energy production from renewable resources. Of these, wind power and photovoltaics show heavily fluctuating supply profiles, with significant impact on energy supply grids. One approach to lessening the load on power grids, aside from their expansion, is to install energy storage systems. Recent studies on the use of such storage systems for improved grid integration of photovoltaic systems have shown the viability of this approach for ground-mounted plants connected to the medium or high voltage level as well as for roof-mounted plants for the low-voltage level.

PWM Regulation of Grid-Tied PV System on the Base of Photovoltaic-Fed Diode-Clamped Inverters

Directory of Open Access Journals (Sweden)

Oleschuk V.I.

2015-12-01

Full Text Available Investigation of grid-tied photovoltaic system on the base of two diode-clamped inverters, controlled by specific algorithms of pulse-width modulation (PWM, has been done. This system includes two strings of photovoltaic panels feeding two diode-clamped inverters. The outputs of inverters are connected with the corresponding windings on the primary side of three-phase transformer, connected with a grid. In order to reduce phase voltage distortion and to increase efficiency of operation of the system, special scheme of control and modulation of inverters has been used, providing minimization of common-mode voltages and voltage waveforms symmetries under different operating conditions. Detailed simulation of processes in this photovoltaic-fed power conversion system has been executed. The results of simulations verify good performance of photovoltaic system regulated in accordance with specific strategy of control and modulation.

A Sensorless Power Reserve Control Strategy for Two-Stage Grid-Connected PV Systems

OpenAIRE

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2017-01-01

Due to the still increasing penetration of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A power reserve control, where namely the active power from the PV panels is reserved during operation, is required for grid support. In this paper, a cost-effective solution to realize the power reserve for two-stage grid-connected PV systems is proposed. The proposed solution routinely employs a Maximum Power Point Track...

Decentralized electricity generation by using photovoltaic grid-connected solar system

International Nuclear Information System (INIS)

Tyutyundziev, N.; Vitanov, P.; Radkov, R.; Grottke, M.

2006-01-01

AcadPV is the first demonstration installation connected permanently to LV grid in Sofia, Bulgaria aiming at assessment of PV efficiencies and cost-effectiveness. A thorough analysis has been carried out in order to select PV system site, supporting construction design and orientation. The PV generator is divided to 3 PV subfields equipped by 3 SUNPOWER inverters connected to 3 separated phases of the grid. The performance of 10kWp PV system has been evaluated during the first year of operation and compared to PV simulation software results

Long term performance analysis of a grid connected photovoltaic system in Northern Ireland

International Nuclear Information System (INIS)

Mondol, Jayanta Deb; Yohanis, Yigzaw; Smyth, Mervyn; Norton, Brian

2006-01-01

The performance of a 13 kW p roof mounted, grid connected photovoltaic system in Northern Ireland over a period of three years has been analysed on hourly, daily and monthly bases. The derived parameters included reference yield, array yield, final yield, array capture losses, system losses, PV and inverter efficiencies and performance ratio. The effects of insolation and inverter operation on the system performance were investigated. The monthly average daily PV, system and inverter efficiencies varied from 4.5% to 9.2%, 3.6% to 7.8% and 50% to 87%, respectively. The annual average PV, system and inverter efficiencies were 7.6%, 6.4% and 75%, respectively. The monthly average daily DC and AC performance ratios ranged from 0.35 to 0.74 and 0.29 to 0.66, respectively. The annual average monthly AC performance ratios for the three years were 0.60, 0.61 and 0.62, respectively. The performance of this system is compared with that of other representative systems internationally

Performance evaluation of 10 MW grid connected solar photovoltaic power plant in India

Directory of Open Access Journals (Sweden)

B. Shiva Kumar

2015-11-01

Full Text Available The growing energy demand in developing nations has triggered the issue of energy security. This has made essential to utilize the untapped potential of renewable resources. Grid connected PV systems have become the best alternatives in renewable energy at large scale. Performance analysis of these grid connected plants could help in designing, operating and maintenance of new grid connected systems. A 10 MW photovoltaic grid connected power plant commissioned at Ramagundam is one of the largest solar power plants with the site receiving a good average solar radiation of 4.97 kW h/m2/day and annual average temperature of about 27.3 degrees centigrade. The plant is designed to operate with a seasonal tilt. In this study the solar PV plant design aspects along with its annual performance is elaborated. The various types of power losses (temperature, internal network, power electronics, grid connected etc. and performance ratio are also calculated. The performance results of the plant are also compared with the simulation values obtained from PV syst and PV-GIS software. The final yield (Y F of plant ranged from 1.96 to 5.07 h/d, and annual performance ratio (PR of 86.12%. It has 17.68% CUF with annual energy generation of 15798.192 MW h/Annum.

Control of Grid Connected Photovoltaic System Using Three-Level T-Type Inverter

Science.gov (United States)

Zorig, Abdelmalik; Belkeiri, Mohammed; Barkat, Said; Rabhi, Abdelhamid

2016-08-01

Three-level T-Type inverter (3LT2I) topology has numerous advantageous compared to three-level neutral-point-clamped (NPC) inverter. The main benefits of 3LT2I inverter are the efficiency, inverter cost, switching losses, and the quality of output voltage waveforms. In this paper, a photovoltaic distributed generation system based on dual-stage topology of DC-DC boost converter and 3LT2I is introduced. To that end, a decoupling control strategy of 3LT2I is proposed to control the current injected into the grid, reactive power compensation, and DC-link voltage. The resulting system is able to extract the maximum power from photovoltaic generator, to achieve sinusoidal grid currents, and to ensure reactive power compensation. The voltage-balancing control of two split DC capacitors of the 3LT2I is achieved using three-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The proposed system performance is investigated at different operating conditions.

A Sensorless Power Reserve Control Strategy for Two-Stage Grid-Connected PV Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2017-01-01

Due to the still increasing penetration of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A power reserve control, where namely the active power from the PV panels is reserved during operation, is required for grid...... support. In this paper, a cost-effective solution to realize the power reserve for two-stage grid-connected PV systems is proposed. The proposed solution routinely employs a Maximum Power Point Tracking (MPPT) control to estimate the available PV power and a Constant Power Generation (CPG) control...... performed on a 3-kW two-stage single-phase grid-connected PV system, where the power reserve control is achieved upon demands....

Modeling, control, and simulation of grid connected intelligent hybrid battery/photovoltaic system using new hybrid fuzzy-neural method.

Science.gov (United States)

Rezvani, Alireza; Khalili, Abbas; Mazareie, Alireza; Gandomkar, Majid

2016-07-01

Nowadays, photovoltaic (PV) generation is growing increasingly fast as a renewable energy source. Nevertheless, the drawback of the PV system is its dependence on weather conditions. Therefore, battery energy storage (BES) can be considered to assist for a stable and reliable output from PV generation system for loads and improve the dynamic performance of the whole generation system in grid connected mode. In this paper, a novel topology of intelligent hybrid generation systems with PV and BES in a DC-coupled structure is presented. Each photovoltaic cell has a specific point named maximum power point on its operational curve (i.e. current-voltage or power-voltage curve) in which it can generate maximum power. Irradiance and temperature changes affect these operational curves. Therefore, the nonlinear characteristic of maximum power point to environment has caused to development of different maximum power point tracking techniques. In order to capture the maximum power point (MPP), a hybrid fuzzy-neural maximum power point tracking (MPPT) method is applied in the PV system. Obtained results represent the effectiveness and superiority of the proposed method, and the average tracking efficiency of the hybrid fuzzy-neural is incremented by approximately two percentage points in comparison to the conventional methods. It has the advantages of robustness, fast response and good performance. A detailed mathematical model and a control approach of a three-phase grid-connected intelligent hybrid system have been proposed using Matlab/Simulink. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Economic and Environmental Study of Wineries Powered by Grid-Connected Photovoltaic Systems in Spain

Directory of Open Access Journals (Sweden)

Daniel Gómez-Lorente

2017-02-01

Full Text Available This research developed a system that can make factories more independent from the grid. The system enhances efficiency since factory operation is powered by the renewable energy generated during the production process. Winemaking is a key sector that can profit from such a system because wineries can recycle much of the waste from the raw materials employed in wine production. Moreover, the solar energy collected at winemaking facilities can also be used to reduce electricity consumption and thus increase energy efficiency. This study investigated the feasibility of using renewable energy sources, such as solar energy, in wineries in Spain, given the quantity of renewable energy produced in the country. For this purpose, cost-effectiveness, power generation, CO2 emissions and the renewable energy fraction were taken into account. The assumption was that the photovoltaic system was grid-connected. Research results showed a reduction in electrical power costs ranging from 4% to 36%. This reduction was accompanied by an increase in the use of renewable energy of up to 57%. The results obtained are based on self-consumption or net metering policy as well as the production capacity of the winery.

Interharmonics from Grid-Connected PV Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

2017-01-01

As the penetration level of grid-connected Photovoltaic (PV) systems increases, the power quality is one of the major concerns for system operators and the demands are becoming even stricter. The impact of interharmonics on the grid has been acknowledged in recent research when considering a large......-scale adoption of PV inverters. However, the origins of interharmonics remain unclear. Thus, this paper performs tests on a commercial PV inverter to explore interharmonic generation and more important investigates the mechanism of interharmonic emission. The investigation reveals that the perturbation...... of the solutions. Simulation results indicate that the constant-voltage MPPT method is the most suitable solution to the mitigation of interharmonics introduced by the MPPT operation, as it avoids the perturbation in the PV voltage during operation....

Performance Parameters for Grid-Connected PV Systems

Energy Technology Data Exchange (ETDEWEB)

Marion, B.; Adelstein, J.; Boyle, K.; Hayden, H.; Hammond, B.; Fletcher, T.; Canada, B.; Narang, D.; Shugar, D.; Wenger, H.; Kimber, A.; Mitchell, L.; Rich, G.; Townsend, T.

2005-02-01

The use of appropriate performance parameters facilitates the comparison of grid-connected photovoltaic (PV) systems that may differ with respect to design, technology, or geographic location. Four performance parameters that define the overall system performance with respect to the energy production, solar resource, and overall effect of system losses are the following: final PV system yield, reference yield, performance ratio, and PVUSA rating. These performance parameters are discussed for their suitability in providing desired information for PV system design and performance evaluation and are demonstrated for a variety of technologies, designs, and geographic locations. Also discussed are methodologies for determining system a.c. power ratings in the design phase using multipliers developed from measured performance parameters.The use of appropriate performance parameters facilitates the comparison of grid-connected photovoltaic (PV) systems that may differ with respect to design, technology, or geographic location. Four performance parameters that define the overall system performance with respect to the energy production, solar resource, and overall effect of system losses are the following: final PV system yield, reference yield, performance ratio, and PVUSA rating. These performance parameters are discussed for their suitability in providing desired information for PV system design and performance evaluation and are demonstrated for a variety of technologies, designs, and geographic locations. Also discussed are methodologies for determining system a.c. power ratings in the design phase using multipliers developed from measured performance parameters.

Mission Profile Translation to Capacitor Stresses in Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Ma, Ke; Wang, Huai

2014-01-01

DC capacitors are widely adopted in grid-connected PhotoVoltaic(PV) systems for power stabilization and control decoupling. They have become one of the critical components in grid-connected PV inverters in terms of cost, reliability and volume. The electrical and thermal stresses of the DC...... stresses of the DC capacitors under both normal and abnormal grid conditions. As a consequence, this investigation provides new insights into the sizing and reliability prediction of those capacitors with respect to priorart studies. Two study cases on a single-stage PV inverter and a two-stage PV inverter...

Performance analysis of a grid connected photovoltaic park on the island of Crete

International Nuclear Information System (INIS)

Kymakis, Emmanuel; Kalykakis, Sofoklis; Papazoglou, Thales M.

2009-01-01

The favorable climate conditions of the island of Crete and the recent legislation for utilization of renewable energy sources provide a substantial incentive for installation of photovoltaic power plants. In this paper, the grid connected photovoltaic park of C. Rokas SA in Sitia, Crete, is presented, and its performance is evaluated. The photovoltaic park has a peak power of 171.36 kW p and has been in operation since 2002. The park is suitably monitored during 1 year, and the performance ratio and the various power losses (temperature, soiling, internal, network, power electronics, grid availability and interconnection) are calculated. The PV park supplied 229 MW h to the grid during 2007, ranging from 335.48 to 869.68 kW h. The final yield (Y F ) ranged from 1.96 to 5.07 h/d, and the performance ratio (PR) ranged from 58 to 73%, giving an annual PR of 67.36%

Promotional drivers for grid-connected PV

Energy Technology Data Exchange (ETDEWEB)

Lopez Polo, A.; Hass, R.; Suna, D.

2009-03-15

This report for the International Energy Agency (IEA) made by Task 10 of the Photovoltaic Power Systems (PVPS) programme takes a look at promotional measures for grid-connected photovoltaic systems. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. The objective of Task 10 is stated as being to enhance the opportunities for wide-scale, solution-oriented application of photovoltaics in the urban environment. The paper discusses the core objective of this study which was to analyse the success of various governmental regulatory programs and governmental and non-governmental marketing programs for grid-connected PV systems. To meet this objective, a review of the most important past and current programs around the world was conducted. The theoretical bases of supply and demand are explained and the types of existing strategies are documented in a second Section. In Chapter 3, various programs around the world are described. Chapter 4 focuses on defining success criteria which will be used for the analysis of the programs. Finally, the major conclusions drawn complete this analysis.

Overview of Grid Codes for Photovoltaic Integration

DEFF Research Database (Denmark)

Zheng, Qianwei; Li, Jiaming; Ai, Xiaomeng

2017-01-01

The increasing grid-connected photovoltaic (PV) power stations might threaten the safety and stability of power system. Therefore, the grid code is developed for PV power stations to ensure the security of PV integrated power systems. In this paper, requirements for PV power integration in differ...... in different grid codes are first investigated. On this basis, the future advocacy is concluded. Finally, several evaluation indices are proposed to quantify the grid code compliance so that the system operators can validate all these requirements by simulation....

Distributed Power System Virtual Inertia Implemented by Grid-Connected Power Converters

DEFF Research Database (Denmark)

Fang, Jingyang; Li, Hongchang; Tang, Yi

2018-01-01

Renewable energy sources (RESs), e.g. wind and solar photovoltaics, have been increasingly used to meet worldwide growing energy demands and reduce greenhouse gas emissions. However, RESs are normally coupled to the power grid through fast-response power converters without any inertia, leading...... to decreased power system inertia. As a result, the grid frequency may easily go beyond the acceptable range under severe frequency events, resulting in undesirable load-shedding, cascading failures, or even large-scale blackouts. To address the ever-decreasing inertia issue, this paper proposes the concept...... of distributed power system virtual inertia, which can be implemented by grid-connected power converters. Without modifications of system hardware, power system inertia can be emulated by the energy stored in the dc-link capacitors of grid-connected power converters. By regulating the dc-link voltages...

Dynamic voltage stability of a distribution system with high penetration of grid-connected photovoltaic type solar generators

Directory of Open Access Journals (Sweden)

Zetty Adibah Kamaruzzaman

2016-06-01

Full Text Available This paper presents the impact of grid-connected photovoltaic (PV generator on dynamic voltage stability of a power distribution system by considering solar intermittency, PV penetration level, and contingencies such as line outage and load increase. The IEEE 13 node test feeder is used as a test system, and a solar PV of 0.48 kV/0.5 MVA is integrated into the test system. Test results show that system voltage is stable at high PV penetration levels. Increase in load causes voltage instability, in which voltage drops below its allowable operating limit. Thus, increase in PV penetration level does not improve system voltage stability because the system experiences voltage collapse during line outage.

High-Efficiency High Step-Up DC-DC Converter with Dual Coupled Inductors for Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Forouzesh, Mojtaba; Shen, Yanfeng; Siwakoti, Yam Prasad

2018-01-01

with a common ground connection of the input and output make the proposed topology a proper candidate for a transformer-less grid connected photovoltaic systems. The operating performance, analysis and mathematical derivations of the proposed dc-dc converter have been demonstrated in the paper. Moreover......This paper introduces a non-isolated high step-up dc-dc converter with dual coupled inductors suitable for distributed generation applications. By implementing an input parallel connection, the proposed dc-dc structure inherits shared input current with low ripple, which also requires small...... capacitive filter at its input. Moreover, this topology can reach high voltage gain by using dual coupled inductors in series connection at the output stage. The proposed converter uses active clamp circuits with a shared clamp capacitor for the main switches. In addition to the active clamp circuit...

Grid-connected photovoltaic systems. Projecting, construction, sales - hints for expert technicians. 3. new rev. ed.; Netzgekoppelte Photovoltaikanlangen. Planung, Errichtung und Verkauf fuer den Handwerksprofi

Energy Technology Data Exchange (ETDEWEB)

Sandner, Thomas

2013-02-01

Photovoltaic conversion is one of the most efficient and also one of the fastest-growing sustainable technologies. The book starts by presenting the fundamentals of photovoltaic conversion and solar radiation and then proceeds to describe the components of grid-connected PV systems. Other issues of this book consider: On-site visit and selection of a suitable generator array; The Renewable Energy Law and the development of photovoltaic conversion in Germany; Business topics such as costs and prices, marketing, quality assurance; Internal use of solar power.

Distribution Grid Integration of Photovoltaic Systems in Germany – Implications on Grid Planning and Grid Operation

International Nuclear Information System (INIS)

Stetz, Thomas

2017-01-01

Photovoltaic is the most dispersed renewable energy source in Germany, typically interconnected to low and medium voltage systems. In recent years, cost-intensive grid reinforcements had to be undertaken all across Germany’s distribution grids in order to increase their hosting capacity for these photovoltaic installations. This paper presents an overview on research results which show that photovoltaic itself can provide ancillary services to reduce its cost of interconnection. Especially the provision of reactive power turned out to be a technically effective and economically efficient method to increase a grid’s hosting capacity for photovoltaic capacity. Different reactive power control methods were investigated, revealing significant differences with regards to their grid operation implications. Business cases for residential-scale photovoltaic applications have shifted from feed-in-tariff based active power feed-in to self-consumption. However, increasing the photovoltaic self-consumption by additional battery-storage systems is still not economically reliable in Germany. (author)

Controllable Photovoltaic Grid Power Injection with an Assistance of Energy Storage System

DEFF Research Database (Denmark)

Morvaj, Boran; Dragicevic, Tomislav; Krajcar, Slavko

2013-01-01

This paper focuses on modeling and simulation of controllable Photovoltaic Battery Power System (PV BPS) interconnected to the electrical utility. After elaboration of modeling principles for different components appearing in the system, simulations of two types of PV plants connected to one branch...... of distribution network have been carried out. First one is connected through a three-phase inverter with battery string connected to a DC-link and the second string is connected to the grid in single phase configuration. In this proposed configuration unpredictable variations of irradiation and temperature...

Statistical Analysis of the Grid Connected Photovoltaic System Performance Ratio

Directory of Open Access Journals (Sweden)

Javier Vilariño-García

2017-05-01

Full Text Available A methodology based on the application of variance analysis and Tukey's method to a data set of solar radiation in the plane of the photovoltaic modules and the corresponding values of power delivered to the grid at intervals of 10 minutes presents from sunrise to sunset during the 52 weeks of the year 2013. These data were obtained through a monitoring system located in a photovoltaic plant of 10 MW of rated power located in Cordoba, consisting of 16 transformers and 98 investors. The application of the comparative method among the middle of the performance index of the processing centers to detect with an analysis of variance if there is significant difference in average at least the rest at a level of significance of 5% and then by testing Tukey which one or more processing centers that are below average due to a fault to be detected and corrected are.

Control of Power and Voltage of Solar Grid Connected

OpenAIRE

Allah, Boucetta Abd; Djamel, Labed

2016-01-01

Renewable energy is high on International agendas. Currently, grid-connected photovoltaic systems are a popular technology to convert solar energy into electricity. Control of power injected into the grid, maximum power point, high efficiency, and low total harmonic distortion of the currents injected into the grid are the requirements for inverter connection into the grid. Consequently, the performance of the inverters connected to the grid depends largely on the control strategy applied. In...

Three-phase Photovoltaic Systems

DEFF Research Database (Denmark)

Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

2015-01-01

, detailing the different photovoltaic inverter structures and topologies as well as discussing the different control layers within a grid-connected photovoltaic plant. Modulation schemes for various photovoltaic inverter topologies, grid synchronization, current control, active and reactive power control......Photovoltaic technology has experienced unprecedented growth in the last two decades, transforming from mainly off-grid niche generation to a major renewable energy technology, reaching approximately 180 GW of capacity worldwide at the end of 2014. Large photovoltaic power plants interfacing...... the grid through a three-phase power electronic converter are now well on the way to becoming a major player in the power system in many countries. Therefore, this article gives an overview of photovoltaic systems with a focus on three-phase applications, presenting these both from a hardware point of view...

Supervision and control of grid connected PV-Storage systems with the five level diode clamped inverter

International Nuclear Information System (INIS)

Himour, Kamal; Ghedamsi, Kaci; Berkouk, El Madjid

2014-01-01

Highlights: • Use of battery bank in grid connection photovoltaic system to ensure the energetic autonomy of the system. • Improve the quality of energy by the use of five-level inverter in a grid connection PV generation system. • Control of inverter by fast and simplified space vector pulse width modulation. • Control and supervision of active and reactive power in the grid. - Abstract: This paper aimed to evaluate the use of photovoltaic-battery storage systems to supply electric power in the distribution grid through a multilevel inverter. The proposed system is composed by four PV generators with MPPT (P and O) control, four battery storage systems connected to each capacitor of the DC link and a five level diode clamped inverter connected to the grid by a traditional three phase transformer. The proposed control has a hierarchical structure with both a grid side control level to regulate the power and the current injected to the grid and four input side regulation units. The system operator controls the power production of the four PV generators by sending out reference power signals to each input side regulation unit, the input side regulation units regulate the voltage of each capacitor of the DC link, regulate the voltage and the state of charge of each battery storage system

Case study of a grid connected with a battery photovoltaic system: V-trough concentration vs. single-axis tracking

International Nuclear Information System (INIS)

Tina, G.M.; Scandura, P.F.

2012-01-01

Highlights: ► PV systems with sun tracking and concentrators (CPVS) can reduce the cost of energy per kWh produced. ► The V-trough low-concentration system solution is compatible with flat PV module technologies. ► Optical, thermal and electrical models are needed to forecast real power production. ► The description of a PV grid connected system with batteries, a one-axis tracker and CPV photovoltaic system is presented. ► Outdoor measurements of the generating system are provided and discussed. - Abstract: Photovoltaic systems (PVSs) combined with either some form of storage, such as a battery energy storage system (BESS), or direct load control, can play a crucial role in achieving a more economical operation of the electric utility system while enhancing its reliability with additional energy sources. At the same time, it is also important to use cost-effective PV solutions. In this context, a low-concentration PVS (CPVS) is analysed as a feasible alternative. This paper, present a case study of a complex PVS, composed of two PVSs, a storage system (BEES) and an inverter that allows the system to operate in both the island and grid-connected modes. The first PVS, is a 2.76-kWp single-axis tracking system (azimuth) with modules facing south and tilted 30°, while the second PVS is a dual-axis tracking system, rated 860 Wp, consisting of a concentrator at the flat mirrors (DoubleSun® Four). The system is installed on the roof of the main building of the “ITIS Marconi” school (Italy). A detailed description of the system is provided, and preliminary operating data are presented and discussed. The efficiencies of the PV systems are calculated and measured to evaluate the cost effectiveness of a low-concentration system.

Performance Analysis of a Grid-Connected Upgraded Metallurgical Grade Silicon Photovoltaic System

Directory of Open Access Journals (Sweden)

Chao Huang

2016-05-01

Full Text Available Because of their low cost, photovoltaic (PV cells made from upgraded metallurgical grade silicon (UMG-Si are a promising alternative to conventional solar grade silicon-based PV cells. This study investigates the outdoor performance of a 1.26 kW grid-connected UMG-Si PV system over five years, reporting the energy yields and performance ratio and estimating the long-term performance degradation rate. To make this investigation more meaningful, the performance of a mono-Si PV system installed at the same place and studied during the same period of time is presented for reference. Furthermore, this study systematizes and rationalizes the necessity of a data selection and filtering process to improve the accuracy of degradation rate estimation. The impact of plane-of-array irradiation threshold for data filtering on performance ratio and degradation rate is also studied. The UMG-Si PV system’s monthly performance ratio after data filtering ranged from 84% to 93% over the observation period. The annual degradation rate was 0.44% derived from time series of monthly performance ratio using the classical decomposition method. A comparison of performance ratio and degradation rate to conventional crystalline silicon-based PV systems suggests that performance of the UMG-Si PV system is comparable to that of conventional systems.

A Simulation of Energy Storage System for Improving the Power System Stability with Grid-Connected PV using MCA Analysis and LabVIEW Tool

Directory of Open Access Journals (Sweden)

Jindrich Stuchly

2015-01-01

Full Text Available The large-scale penetration of distributed, Renewable power plants require transfers of large amounts of energy. This, in turn, puts a high strain on the energy delivery infrastructure. In particular, photovoltaic power plants supply energy with high intermittency, possibly affecting the stability of the grid by changing the voltage at the plant connection point. In this contribution, we summarize the main negative effects of selected and real-operated grid connected photovoltaic plant. Thereafter a review of suitable Energy storage systems to mitigate the negative effects has been carried out, compared and evaluated using Multi-criterion analysis. Based on this analysis, data collected at the plant and the grid, are used to design the energy storage systems to support connection of the plant to the grid. The cooperation of these systems is then analysed and evaluated using simulation tools created in LabVIEW for this purpose. The simulation results demonstrate the capability of energy storage system solutions to significantly reduce the negative feedback effects of Photovoltaic Power Plan to the low voltage grid.

Robust maximum power point tracker using sliding mode controller for the three-phase grid-connected photovoltaic system

Energy Technology Data Exchange (ETDEWEB)

Kim, Il-Song [LG Chem. Ltd./Research park, Mobile Energy R and D, 104-1 Moonji-Dong, Yuseong-Gu, Daejeon 305-380 (Korea)

2007-03-15

A robust maximum power point tracker (MPPT) using sliding mode controller for the three-phase grid-connected photovoltaic system has been proposed in this paper. Contrary to the previous controller, the proposed system consists of MPPT controller and current controller for tight regulation of the current. The proposed MPPT controller generates current reference directly from the solar array power information and the current controller uses the integral sliding mode for the tight control of current. The proposed system can prevent the current overshoot and provide optimal design for the system components. The structure of the proposed system is simple, and it shows robust tracking property against modeling uncertainties and parameter variations. Mathematical modeling is developed and the experimental results verify the validity of the proposed controller. (author)

Large scale rooftop photovoltaics grid connected system at Charoenphol-Rama I green building

Energy Technology Data Exchange (ETDEWEB)

Ketjoy, N.; Rakwichian, W. [School of Renewable Energy Technology (SERT) (Thailand); Wongchupan, V. [Panya Consultants Co., Ltd (Thailand); Sankarat, T. [Tesco Lotus, Ek-Chai Distribution System Co., Ltd. (Thailand)

2004-07-01

This paper presents a technical feasibility study project for the large scale rooftop photovoltaics (PV) grid connected system at Charoenphol-Rama I green building super store of TESCO LOTUS (TL) in Thailand. The objective of this project is (i) to study the technical feasibility of installation 350 kWp PV systems on the top of the roof in this site (ii) and to determine the energy produce from this system. The technical factors are examined using a computerized PVS 2000 simulation and assessment tool. This super store building located in Bangkok, with latitude 14 N, longitude 100 E and the building direction is 16 from North direction. The building roof area is 14,000 m2; with 3 degree face East and 3 degree face West pitch. Average daily solar energy in this area is approximately 5.0 kWh. The study team for this project consists of educational institution as School of Renewable Energy Technology (SERT) and private institution as Panya Consultants (PC). TL is the project owner, PC is responsible for project management, and SERT is a third party and responsible for PV system study, conceptual design and all technical process. In this feasibility studies SERT will identify the most attractive scenarios of photovoltaic cell technology (mono, poly-crystalline or thin film amorphous), system design concepts for owners (TL) and determine possibility of the energy yield of the system from different module orientation and tilt angle. The result of this study is a guide to help TL to make decision to select proper rooftop PV system option for this store with proper technology view. The economic view will not be considered in this study. (orig.)

A grid-connected single-phase photovoltaic micro inverter

Science.gov (United States)

Wen, X. Y.; Lin, P. J.; Chen, Z. C.; Wu, L. J.; Cheng, S. Y.

2017-11-01

In this paper, the topology of a single-phase grid-connected photovoltaic (PV) micro-inverter is proposed. The PV micro-inverter consists of DC-DC stage with high voltage gain boost and DC-AC conversion stage. In the first stage, we apply the active clamp circuit and two voltage multipliers to achieve soft switching technology and high voltage gain. In addition, the flower pollination algorithm (FPA) is employed for the maximum power point tracking (MPPT) in the PV module in this stage. The second stage cascades a H-bridge inverter and LCL filter. To feed high quality sinusoidal power into the grid, the software phase lock, outer voltage loop and inner current loop control method are adopted as the control strategy. The performance of the proposed topology is tested by Matlab/Simulink. A PV module with maximum power 300W and maximum power point voltage 40V is applied as the input source. The simulation results indicate that the proposed topology and the control strategy are feasible.

Low Voltage Ride-Through of Two-Stage Grid-Connected Photovoltaic Systems Through the Inherent Linear Power-Voltage Characteristic

DEFF Research Database (Denmark)

Yang, Yongheng; Sangwongwanich, Ariya; Liu, Hongpeng

2017-01-01

In this paper, a cost-effective control scheme for two-stage grid-connected PhotoVoltaic (PV) systems in Low Voltage Ride-Through (LVRT) operation is proposed. In the case of LVRT, the active power injection by PV panels should be limited to prevent from inverter over-current and also energy...... aggregation at the dc-link, which will challenge the dc-link capacitor lifetime if remains uncontrolled. At the same time, reactive currents should be injected upon any demand imposed by the system operators. In the proposed scheme, the two objectives can be feasibly achieved. The active power is regulated...... point tracking controller without significant hardware or software modifications. In this way, the PV system will not operate at the maximum power point, whereas the inverter will not face any over-current challenge but can provide reactive power support in response to the grid voltage fault...

Performance of a grid connected PV system used as active filter

International Nuclear Information System (INIS)

Calleja, Hugo; Jimenez, Humberto

2004-01-01

In this paper, the performance of a grid connected photovoltaic (PV) system used as an active filter is presented. Its main feature is the capability to compensate the reactive and harmonic currents drawn by nonlinear loads while simultaneously injecting into the grid the maximum power available from the cells. The system can also operate as a stand alone active filter. The system was connected to a 1 kW PV array and tested with the loads typically found in households: small motors, personal computers and electronic ballasts. The results show that the system can correct the power factor to values close to unity for all the cases tested, thereby improving the efficiency of the electric energy supply

Performance analysis of the Single-Phase Grid-Connected Inverter of a photovoltaic system in water and wind applications

Directory of Open Access Journals (Sweden)

Borkowski Dariusz

2016-01-01

Full Text Available Single-phase grid connected inverters are nowadays broadly developed and tested in various types of applications especially in photovoltaic systems. The main aim of the inverter control strategy is to extract the maximum energy from the PV system which corresponds to the maximum power at certain conditions. However, the MPPT methods are also important in other renewable energy conversion systems. This paper analyses the performance of a commercially available photovoltaic inverter in water and wind systems. Presented models are implemented in a laboratory test bench in the form of torque characteristics realised by an induction motor fed by the inverter with vector control. The parameters are scaled into relative variables to provide a proper performance comparison. Presented tests include step response to assess the performance of a system dynamic. The dynamic tests showed a fast response of the investigated systems. The MPPT tracking accuracy tested under realistic profiles is similar for both cases: 98% and 96% respectively for the wind and water systems. These results prove the satisfactory performance of the MPPT of the PV microinverter in these applications.

MODELING SIMULATION AND PERFORMANCE STUDY OF GRIDCONNECTED PHOTOVOLTAIC ENERGY SYSTEM

OpenAIRE

Nagendra K; Karthik J; Keerthi Rao C; Kumar Raja Pemmadi

2017-01-01

This paper presents Modeling Simulation of grid connected Photovoltaic Energy System and performance study using MATLAB/Simulink. The Photovoltaic energy system is considered in three main parts PV Model, Power conditioning System and Grid interface. The Photovoltaic Model is inter-connected with grid through full scale power electronic devices. The simulation is conducted on the PV energy system at normal temperature and at constant load by using MATLAB.

River Debris Management System using Off-Grid Photovoltaic Module

Directory of Open Access Journals (Sweden)

Saadon Intan Mastura

2017-01-01

Full Text Available In Malaysia, Malacca River has long been the tourism attraction in Malacca. However, due to negligence, the river has been polluted by the litters thrown by tourists and even local residents, thus reflects a negative perception on Malacca. Therefore, this paper discusses about a fully automated river debris management system development using a stand-alone photovoltaic system. The concept design is to be stand alone in the river and automatically pull debris towards it for disposal. An off-grid stand-alone photovoltaic solar panel is used as renewable energy source connected to water pump and Arduino Uno microcontroller. The water pump rotates a water wheel and at the same time moves a conveyor belt; which is connected to the water wheel by a gear for debris collection. The solar system sizing suitable for the whole system is shown in this paper. The dumpster barge is equipped with an infrared sensor to monitor maximum height for debris, and instruct Arduino Uno to turn off the water pump. This system is able to power up using solar energy on sunny days and using battery otherwise.

Power Quality Improvement Utilizing Photovoltaic Generation Connected to a Weak Grid

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tumbelaka, Hanny H. [Petra Christian University; Gao, Wenzhong [UNiversity of Denver

2017-11-07

Microgrid research and development in the past decades have been one of the most popular topics. Similarly, the photovoltaic generation has been surging among renewable generation in the past few years, thanks to the availability, affordability, technology maturity of the PV panels and the PV inverter in the general market. Unfortunately, quite often, the PV installations are connected to weak grids and may have been considered as the culprit of poor power quality affecting other loads in particular sensitive loads connected to the same point of common coupling (PCC). This paper is intended to demystify the renewable generation, and turns the negative perception into positive revelation of the superiority of PV generation to the power quality improvement in a microgrid system. The main objective of this work is to develop a control method for the PV inverter so that the power quality at the PCC will be improved under various disturbances. The method is to control the reactive current based on utilizing the grid current to counteract the negative impact of the disturbances. The proposed control method is verified in PSIM platform. Promising results have been obtained.

Grid converters for photovoltaic and wind power systems

CERN Document Server

Teodorescu, Remus; Rodríguez, Pedro

2011-01-01

"Grid Converters for Photovoltaic and Wind Power Systems provides a comprehensive description of the control of grid converters for photovoltaic and wind power systems. The authors present a range of control methods for meeting the latest application, power quality and power conversion requirements and standards, as well as looking towards potential future control functions. Practical examples, exercises, and an accompanying website with simulation models using Matlab and Simulink environments, and PSIM software make this text a pragmatic resource for electrical engineers as well as students taking related courses"--

Fuzzy comprehensive evaluation for grid-connected performance of integrated distributed PV-ES systems

Science.gov (United States)

Lv, Z. H.; Li, Q.; Huang, R. W.; Liu, H. M.; Liu, D.

2016-08-01

Based on the discussion about topology structure of integrated distributed photovoltaic (PV) power generation system and energy storage (ES) in single or mixed type, this paper focuses on analyzing grid-connected performance of integrated distributed photovoltaic and energy storage (PV-ES) systems, and proposes a comprehensive evaluation index system. Then a multi-level fuzzy comprehensive evaluation method based on grey correlation degree is proposed, and the calculations for weight matrix and fuzzy matrix are presented step by step. Finally, a distributed integrated PV-ES power generation system connected to a 380 V low voltage distribution network is taken as the example, and some suggestions are made based on the evaluation results.

Technical and economic analysis of a 1mw grid-connected solar photovoltaic power system at KNUST-Kumasi

International Nuclear Information System (INIS)

Nyarko Kumi, Ebenezer

2012-09-01

Grid-connected solar PV systems, though the fastest growing renewable energy technology in the world, have not been fully exploited in Africa; one of the reasons being the very high initial investment. Prices of solar PV systems have however been on a decline for the past few years due to technological innovations which have led to improvements in cell efficiencies and the economies of scale resulting from increase in production. The main purpose of this thesis is to present a technical and economic analysis of a 1MW grid-connected solar photovoltaic power system for the Kwame Nkrumah University of Science and Technology (KNUST), Kumasi using rooftops of buildings on the campus. A solar resource assessment done to know the amount of solar radiation available at KNUST showed that KNUST receives about 4.30kWh/m 2 /day. A roof assessment which considered parameters such as the surface orientation and pitch of roofs, roof area and the possibility of shading of the roof, also revealed there is about 43,697m 2 of roof space available for grid-connected solar PV installations. In technical analysis of the 1MWp solar PV system, the three (3) commonest solar PV module technologies were selected and their performance simulated using PVsyst software. Amorphous silicon modules were found to perform better than monocrystalline and polycrystalline modules over the one (1) year simulation period. The financial analysis carried out using RETScreen revealed that at a solar PV market price of US$4.45/Wp and a tariff of US$0.11/kWh (tariff paid for Asogli Power Plant which happens to be the most expensive generation source in the country), the project is not viable unless feed-in tariffs greater than US$0.43/kWh are paid. (au)

Modeling and Coordinated Control Strategy of Large Scale Grid-Connected Wind/Photovoltaic/Energy Storage Hybrid Energy Conversion System

Directory of Open Access Journals (Sweden)

Lingguo Kong

2015-01-01

Full Text Available An AC-linked large scale wind/photovoltaic (PV/energy storage (ES hybrid energy conversion system for grid-connected application was proposed in this paper. Wind energy conversion system (WECS and PV generation system are the primary power sources of the hybrid system. The ES system, including battery and fuel cell (FC, is used as a backup and a power regulation unit to ensure continuous power supply and to take care of the intermittent nature of wind and photovoltaic resources. Static synchronous compensator (STATCOM is employed to support the AC-linked bus voltage and improve low voltage ride through (LVRT capability of the proposed system. An overall power coordinated control strategy is designed to manage real-power and reactive-power flows among the different energy sources, the storage unit, and the STATCOM system in the hybrid system. A simulation case study carried out on Western System Coordinating Council (WSCC 3-machine 9-bus test system for the large scale hybrid energy conversion system has been developed using the DIgSILENT/Power Factory software platform. The hybrid system performance under different scenarios has been verified by simulation studies using practical load demand profiles and real weather data.

Actual performance and characteristic of a grid connected photovoltaic power system in the tropics: A short term evaluation

International Nuclear Information System (INIS)

Khatib, Tamer; Sopian, Kamaruzzaman; Kazem, Hussein A.

2013-01-01

Highlights: • We analyzed an actual performance of grid connected PV system. • We derived accurate models for the system based on the actual performance. • We assist the electricity productively of the proposed system. - Abstract: This paper presents a field operation experience for a grid connected PV system under tropical climate. The system is consisted of a 5 kWp photovoltaic (PV) array and a 6 kW DC/AC inverter. The operation performance data are recorded in order to develop accurate mathematical models for the system as well as to evaluate the productivity of the system. The experiment results show that, the average PV performance (the ratio of the theoretical performance to the actual performance) is 73.12% while the average inverter performance (the ratio of the theoretical inverter efficiency to the actual inverter efficiency) is 98.56%. Moreover, it is found that the daily yield factor of the PV system is 2.51 kW h/kWp day while, the capacity factor is 10.47%. However, it is concluded that the productivity of the system is below the prospected rate and thus, an inspection of the system must be done in order to diagnose the problem of the system’s low productivity. This paper presents worthwhile information for those who are interested in PV system installation in Malaysia and nearby country

Grid Connected Solar PV System with SEPIC Converter Compared with Parallel Boost Converter Based MPPT

OpenAIRE

Bosco Raj, T. Ajith; Ramesh, R.; Maglin, J. R.; Vaigundamoorthi, M.; William Christopher, I.; Gopinath, C.; Yaashuwanth, C.

2014-01-01

The main objective of this work is to study the behaviour of the solar PV systems and model the efficient Grid-connected solar power system. The DC-DC MPPT circuit using chaotic pulse width modulation has been designed to track maximum power from solar PV module. The conversion efficiency of the proposed MPPT system is increased when CPWM is used as a control scheme. This paper also proposes a simplified multilevel (seven level) inverter for a grid-connected photovoltaic system. The primary g...

A dynamic power management strategy of a grid connected hybrid generation system using wind, photovoltaic and Flywheel Energy Storage System in residential applications

International Nuclear Information System (INIS)

Boukettaya, Ghada; Krichen, Lotfi

2014-01-01

A global supervisory strategy for a micro-grid power generation system that comprises wind and photovoltaic generation subsystems, a flywheel storage system, and domestic loads connected both to the hybrid power generators and to the grid, is developed in this paper. The objectives of the supervisor control are, firstly, to satisfy in most cases the load power demand and, secondly, to check storage and grid constraints to prevent blackout, to reduce energy costs and greenhouse gas emissions, and to extend the life of the flywheel. For these purposes, the supervisor determines online the operation mode of the different generation subsystems, switching from maximum power conversion to power regulation. Decision criteria for the supervisor based on actual variables are presented. Finally, the performance of the supervisor is extensively assessed through computer simulation using a comprehensive nonlinear model of the studied system. - Highlights: • We supervise a micro-grid power generation system with an objective to produce clipping grid consumption. • The supervisor switch online from maximum power conversion to power regulation. • We provide services both for domestic users and for the distribution network manager. • The developed algorithm is tested and validated for different scenarios

Techno-economic feasibility analysis of 1 MW photovoltaic grid connected system in Oman

Directory of Open Access Journals (Sweden)

Hussein A. Kazem

2017-09-01

Full Text Available Solar photovoltaic panels (PV face many challenges in the Sultanate of Oman. These challenges include costs, policy and technical development. With the growing needs of the Sultanate in the energy sector, Grid Connected PV (GCPV system could help in reducing peak load demand and offer an alternative energy source. This study aims to numerically discover the optimal configuration for a 1 MW GCPV plant in Adam city. Real time data, on hour-by-hour basis, from the location are used to ensure highest accuracy. The simulation not only is set for technical evaluation but economic as well. Investment in GCPV technology needs a bigger push both by research, development and policy. The assessment results show that the PV technology investment is very promising in this site whereas the annual yield factor of the system is 1875.1 kW h/kW p. Meanwhile, the capacity factor of the proposed system is 21.7%. The cost of energy found for the plant is around 0.2258 USD/kW h which is economically feasible and shows great promise.

Control and performance analysis of grid connected photovoltaic systems of two different technologies in a desert environment

Directory of Open Access Journals (Sweden)

Layachi ZAGHBA

2017-12-01

Full Text Available In this study, is to investigate the effect of real climatic conditions on the performance parameters of a 9 kWp grid connected photovoltaic plant during one-year using typical days installed in the desert environment in south of Algeria (Ghardaia site. The PV plant contain the following components: solar PV array, with a DC/DC boost converter, neural MPPT, that allow maximal power conversion into the grid, have been included. These methods can extract maximum power from each of the independent PV arrays connected to DC link voltage level, a DC/AC inverter and a PI current control system. The PV array is divides in two parallel PV technology types; the first includes 100 PV modules mono-crystalline silicon (mc-Si arranged in 20 parallel groups of 5 modules in series, and the second of composed of 24 amorphous modules (Inventux X series, arranged in 6 parallel groups of 4 modules in series. The proposed system tested using MATLAB/SIMULINK platform in which a maximum power tracked under constant and real varying solar irradiance. The study concluded that output power and energy from two PV technology types (mc-Si and Amorphous-Si increases linearly with increase of solar irradiance.

Real-time prediction models for output power and efficiency of grid-connected solar photovoltaic systems

International Nuclear Information System (INIS)

Su, Yan; Chan, Lai-Cheong; Shu, Lianjie; Tsui, Kwok-Leung

2012-01-01

Highlights: ► We develop online prediction models for solar photovoltaic system performance. ► The proposed prediction models are simple but with reasonable accuracy. ► The maximum monthly average minutely efficiency varies 10.81–12.63%. ► The average efficiency tends to be slightly higher in winter months. - Abstract: This paper develops new real time prediction models for output power and energy efficiency of solar photovoltaic (PV) systems. These models were validated using measured data of a grid-connected solar PV system in Macau. Both time frames based on yearly average and monthly average are considered. It is shown that the prediction model for the yearly/monthly average of the minutely output power fits the measured data very well with high value of R 2 . The online prediction model for system efficiency is based on the ratio of the predicted output power to the predicted solar irradiance. This ratio model is shown to be able to fit the intermediate phase (9 am to 4 pm) very well but not accurate for the growth and decay phases where the system efficiency is near zero. However, it can still serve as a useful purpose for practitioners as most PV systems work in the most efficient manner over this period. It is shown that the maximum monthly average minutely efficiency varies over a small range of 10.81% to 12.63% in different months with slightly higher efficiency in winter months.

Study on unitized inverter with photovoltaic grid-connected and stand-alone functions

Energy Technology Data Exchange (ETDEWEB)

Wang, Haining; Su, Jianhui; Ding, Ming [Hefei University of Technology, Hefei (China)

2008-07-01

The main circuit and algorithm of unitized single phase inverter are presented, in which photovoltaic (PV) grid-connected algorithm, independency sine inverter algorithm and storage battery charge administer are all integrated basing on DSP (Digital Signal Processor). The control system identifies utility failure initiatively and then switches to independency power supply automatically. The methods of charging battery are multiform. Basing on material term to use utility or solar array to charge can optimize charge efficiency, assure the capacitance of battery and prolong life-span of battery. In addition, some results are offered basing on the prototype of a 2.5kW single phase inverter. (orig.)

A Novel Neutral Point Clamped Full-Bridge Topology for Transformerless Photovoltaic Grid-Connected Inverters

Directory of Open Access Journals (Sweden)

M. Pakdel

2017-04-01

Full Text Available This paper presents a novel neutral point clamped full-bridge topology for transformerless photovoltaic grid-tied inverters. Transformerless grid-connected inverters have been used widely in recent years since they offer higher efficiency and lower costs. Ground leakage current suppression is the main issue which should be considered carefully in transformerless photovoltaic grid-connected inverters. Among different methods used to decline ground leakage current, neutral point clamped (NPC topologies are considered more useful and effective. In NPC topologies, the short-circuited output voltage at the freewheeling period is clamped to the middle of the DC bus voltage. Therefore, the common-mode voltage (CM will be constant at the whole switching period. Various NPC topologies such as H6 [1], HB-ZVR [2], oH5 [3], and PN-NPC [4] have been proposed. In this paper, a novel NPC topology is proposed which has lower power losses and higher efficiency over previous topologies. Furthermore, the proposed NPC topology exhibits a similar ground leakage current with the PN-NPC topology. The proposed NPC topology is analyzed theoretically using simulation studies and an experimental prototype is provided to verify theoretical analysis and simulation studies.

Control of a battery energy storage system connected to a low voltage grid

NARCIS (Netherlands)

van Dun, J.J.C.M.; de Groot, Robert; Morren, Johan; Slootweg, Han

2015-01-01

This paper describes the development of a control algorithm for a battery energy storage system, which is connected to a residential low voltage grid. By predicting future load demand and photovoltaic production within the neighbourhood concerned, flattening of the aggregated neighbourhood

The German experience with grid-connected PV-systems

International Nuclear Information System (INIS)

Erge, T.; Hoffmann, V.U.; Kiefer, K.

2001-01-01

Grid-connected photovoltaics experienced increasing attention in Germany in recent years and are expected to face a major boost at the beginning of the new millennium. Highlights like the German 100,000-Roofs-Solar-Programme, PV programmes at schools financed by utilities and governments (e.g. 'SONNEonline' by PreussenElektra, 'Sonne in der Schule' by BMWi and 'Sonne in der Schule' by Bayernwerk) and large centralised installations of MW size ('Neue Messe Munchen' by Bayernwerk and 'Energiepark Mont-Cenis' by state Nordrhein-Westfalen, Stadtwerke Herne and European Union) count for the potential of grid-connected PV. Today in Germany a typical grid-connected PV installation of 1 kW nominal power produces average annual energy yields of 700 kWh (dependent on location and system components) and shows a high operating availability. The price per kWh from PV installations is still significantly higher than the price for conventional energy, but new funding schemes and cost models (like the large increase of feed-in tariff in Germany due to the Act on Granting Priority to Renewable Energy Sources in 2000) give optimism about the future. (Author)

Three-phase electronic power converter for photovoltaic system connected to power line; Conversor eletronico de potencia trifasico para sistema fotovoltaico conectado a rede eletrica

Energy Technology Data Exchange (ETDEWEB)

Villalva, Marcelo Gradella

2010-10-15

This work is a contribution to the study of power converters for photovoltaic distributed generation systems. The main objective is to present the development and results of a three phase power converter for a grid-connected photovoltaic plant. The work presents experimental results and theoretical studies on the modeling and simulation of photovoltaic devices, regulation of the photovoltaic voltage, maximum power point tracking, and the modeling and control of a two-stage grid-connected power converter. (author)

Battery sizing and rule-based operation of grid-connected photovoltaic-battery system: A case study in Sweden

International Nuclear Information System (INIS)

Zhang, Yang; Lundblad, Anders; Campana, Pietro Elia; Benavente, F.; Yan, Jinyue

2017-01-01

Highlights: • Battery sizing and rule-based operation are achieved concurrently. • Hybrid operation strategy that combines different strategies is proposed. • Three operation strategies are compared through multi-objective optimization. • High Net Present Value and Self Sufficiency Ratio are achieved at the same time. - Abstract: The optimal components design for grid-connected photovoltaic-battery systems should be determined with consideration of system operation. This study proposes a method to simultaneously optimize the battery capacity and rule-based operation strategy. The investigated photovoltaic-battery system is modeled using single diode photovoltaic model and Improved Shepherd battery model. Three rule-based operation strategies—including the conventional operation strategy, the dynamic price load shifting strategy, and the hybrid operation strategy—are designed and evaluated. The rule-based operation strategies introduce different operation parameters to run the system operation. multi-objective Genetic Algorithm is employed to optimize the decisional variables, including battery capacity and operation parameters, towards maximizing the system’s Self Sufficiency Ratio and Net Present Value. The results indicate that employing battery with the conventional operation strategy is not profitable, although it increases Self Sufficiency Ratio. The dynamic price load shifting strategy has similar performance with the conventional operation strategy because the electricity price variation is not large enough. The proposed hybrid operation strategy outperforms other investigated strategies. When the battery capacity is lower than 72 kW h, Self Sufficiency Ratio and Net Present Value increase simultaneously with the battery capacity.

Design for Reliability of Power Electronics for Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Sangwongwanich, Ariya; Blaabjerg, Frede

2016-01-01

Power electronics is the enabling technology for optimizing energy harvesting from renewable systems like Photovoltaic (PV) and wind power systems, and also for interfacing grid-friendly energy systems. Advancements in the power semiconductor technology (e.g., wide band-gap devices) have pushed...... the conversion efficiency of power electronics to above 98%, where however te reliability of power electronics is becoming of high concern. Therefore, it is important to design for reliable power electronic systems to lower the risks of many failures during operation; otherwise will increase the cost...... for maintenance and reputation, thus affecting the cost of PV energy. Today's PV power conversion applications require the power electronic systems with low failure rates during a service life of 20 years or even more. To achieve so, it is vital to know the main life-limiting factors of power electronic systems...

grid-connected photovoltaic system design for local government

African Journals Online (AJOL)

user

wind power and has durability of more than twenty five years with a very minimal .... enhance energy yield of grid connected PV power plant by naturally catching .... cause it to operate at maximum power point irrespective of changing weather ...

Review of the French photovoltaic facilities connected to the grid at the end of March 2012

International Nuclear Information System (INIS)

2012-01-01

This newsletter takes stock of the evolution of the photovoltaic power plants connected and waiting to be connected to the French national grid (mainland France and overseas territories), at the national and regional scale, and sorted by power categories. This issue takes stock of the situation at the end of March 2012

Review of the French photovoltaic facilities connected to the grid at the end of June 2012

International Nuclear Information System (INIS)

2012-01-01

This newsletter takes stock of the evolution of the photovoltaic power plants connected and waiting to be connected to the French national grid (mainland France and overseas territories), at the national and regional scale, and sorted by power categories. This issue takes stock of the situation at the end of June 2012

Are small-scale grid-connected photovoltaic systems a cost-effective policy for lowering electricity bills and reducing carbon emissions? A technical, economic, and carbon emission analysis

International Nuclear Information System (INIS)

McHenry, Mark P.

2012-01-01

This research discusses findings from technical simulations and economic models of 1 kW p and 3 kW p grid-connected photovoltaic (PV) systems supplying a rural home electricity load in parallel with the electricity network in Western Australia (WA). The technical simulations are based on electricity billing, consumption monitoring, an energy audit data, combined with 15 min interval load and PV system performance for commercially available technologies and balance of system components, using long-term meteorological input data. The economic modelling uses 2010 market prices for capital costs, operational costs, electricity tariffs, subsidies, and is based on discounted cash flow analyses which generate a final net present value (NPV) for each system against network electricity costs (in Australian dollars, AUD) over a 15 year investment horizon. The results suggest that current market prices generate a negative NPV (a net private loss), even with the current government subsidies, which lead to higher home electricity costs than conventional network electricity use. Additionally, the private costs of carbon emission mitigation (AUD tCO 2 -e −1 ) for the grid-connected PV system simulations and models were around AUD 600-700 tCO 2 -e −1 , a particularly expensive option when compared to existing large-scale renewable energy mitigation activities. - Highlights: ► Subsidised small-scale grid-connected PV systems can increase home electricity costs. ► Subsidies for private PV systems are provided by those who do not receive a benefit. ► Small-scale grid-connected PV systems result in very high costs of mitigation. ► Verifying actual mitigation from grid-connected small-scale systems is problematic. ► Maintain medium/large-scale grid-connected or small-scale off-grid system subsidies.

Experimental grid connected PV system power analysis

Science.gov (United States)

Semaoui, Smail; Abdeladim, Kamel; Arab, Amar Hadj; Boulahchich, Saliha; Amrouche, Said Ould; Yassaa, Noureddine

2018-05-01

Almost 80 % of Algerian territory is appropriate for the exploitation of solar energy. The Algerian energetic strategy provides a substantial injection of PV electricity to the national grid. Currently, about 344 MWp of PV arrays which corresponds approximately to 2,34 km2 of module surfaces, are connected on electricity grid over the national territory. The Algerian Northern regions are characterized by strong pollution and high humidity. These phenomena affect the energetic productivity of PV generator. The objective of our study is to analyze experimental grid connected PV system power in coastal locations. Hence, experiments have been conducted on three identical PV systems to determine the electrical performances. Transformer-less inverters are the most attractive for the ground-based photovoltaic (PV) system due to their efficiencies, reduced cost and weight. Besides, the absence of the galvanic isolation generates problems of capacitive leakage current on the AC side and the degradation of the insulation resistance on the DC side of the inverter. In this work, experimental study of the behavior of single-phase inverters without transformers is presented. The main objective of this work is to study the degradation of the insulation resistance at the input of the inverter, and the capacitive leakage current at the output of the inverter. This study was achieved at the CDER on a rainy day of 15/03/2017, on the first PV plant connected to the low voltage network in Algeria. This investigation can help forecasting the PV array energetic production by taking into account natural conditions.

Development and Testing of a Prototype Grid-Tied Photovoltaic Power System

Science.gov (United States)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) has developed and tested a prototype 2 kW DC grid-tied photovoltaic (PV) power system at the Center. The PV system has generated in excess of 6700 kWh since operation commenced in July 2006. The PV system is providing power to the GRC grid for use by all. Operation of the prototype PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the prototype PV system, additional PV power system expansion at GRC is under consideration. The prototype grid-tied PV power system was successfully designed and developed which served to validate the basic principles described, and the theoretical work that was performed. The report concludes that grid-tied photovoltaic power systems are reliable, maintenance free, long life power systems, and are of significant value to NASA and the community.

Promotion of grid-connected photovoltaic systems in Spain: Performance analysis of the period 1998-2008

Energy Technology Data Exchange (ETDEWEB)

de la Hoz, Jordi; Boix, Oriol; Martin, Helena [Department of Electrical Engineering, Universitat Politecnica de Catalunya (UPC), Escola Tecnica d' Enginyeria Industrial de Barcelona (EUETIB), Carrer del Comte d' Urgell, 187, 08036 Barcelona (Spain); Martins, Blanca [Department of Business Management, Universitat Politecnica de Catalunya (UPC), Escola Tecnica d' Enginyeria Industrial de Barcelona (EUETIB), Carrer del Comte d' Urgell, 187, 08036 Barcelona (Spain); Graells, Moises [Department of Chemical Engineering, Universitat Politecnica de Catalunya (UPC), Escola Tecnica d' Enginyeria Industrial de Barcelona (EUETIB), Carrer del Comte d' Urgell, 187, 08036 Barcelona (Spain)

2010-12-15

This paper contributes a critical view of the development of grid-connected photovoltaic systems (GCPVS) in Spain during the period 1998-2008 by looking into the different actions that were intended to promote this technology. The Spanish photovoltaic (PV) sector has undergone bullish development in the recent years, but its underlying factors still lack systematic identification and analysis. Accordingly, this paper collects and presents detailed data for describing this evolution. It also makes a special case of the particular promotion of PV systems on roof and goes further to analyze how these actions have affected GCPVS evolution as well as the magnitude of their impact on its performance. The exponential growth of installed cumulative PV power at the end of this period, which largely exceeded the target set for 2008, is canvassed by building an analogy with feedback control systems. In this approach, market response or the PV power attained is considered as the system output, while the different regulation changes are regarded as control actions aimed at enabling GCPVS to hit the energy target. Such an analysis allows determining the most significant delays and control actions that explain the system's performance. Hence, this study suggests an alternative framework to support the formulation and assessment of energy policy as it puts the emphasis not only on the evolution of the system per se but rather on the performance of the system against the energy target. In this regard, it might contribute to enhance the promotion mechanisms of green technologies. (author)

Current Harmonics from Single-Phase Grid-Connected Inverters

DEFF Research Database (Denmark)

Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

2016-01-01

Environmental conditions and operational modes may significantly impact the distortion level of the injected current from single-phase grid-connected inverter systems, such as photovoltaic (PV) inverters, which may operate in cloudy days with a maximum power point tracking, in a non-unity power...... factor, or in the low voltage ride through mode with reactive current injection. In this paper, the mechanism of the harmonic current injection from grid-connected single-phase inverter systems is thus explored, and the analysis is conducted on single-phase PV systems. In particular, the analysis...... is focused on the impacts of the power factor and the feed-in grid current level on the quality of the feed-in grid current from single-phase inverters. As a consequence, an internal model principle based high performance current control solution is tailor-made and developed for single-phase grid-connected...

FY 2000 report on the demonstrative research for photovoltaic power generation system in Thailand. Demonstrative study on photovoltaic power generation grid-connected system

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-09-01

In relation to the demonstrative study of the photovoltaic power system that is planned in Libong island, Thailand, the FY 2000 results were reported. In this R and D, construction/demonstrative operation were planned for a photovoltaic power station with a generation output of 100kW, photovoltaic power system in school facilities, and system for transmitting/distributing power to houses by connecting the power station and power system. In this fiscal year, the field survey was conducted together with the alteration from Yao Yai island, for which the demonstrative study was planned at first, to Libong island. The electric equipment was selected which met the requests from Thailand and the results of the field survey, and the basic design of the photovoltaic power generation/transmission/distribution system was completed. Based on this, the design/manufacture of photovoltaic power generation modules, power control equipment, measuring equipment, etc. were made. At the construction site of photovoltaic power station, construction work such as land formation was conducted. Further, Thai engineers who visited Japan did the following: discussions about power system, presence at test/inspection of photovoltaic power generation modules, visits to photovoltaic power stations, wind power stations, etc. (NEDO)

Performance analysis and investigation of a grid-connected photovoltaic installation in Morocco

Directory of Open Access Journals (Sweden)

Kamal Attari

2016-11-01

Full Text Available The paper present an evaluation of a grid-connected photovoltaic (PV system installed on the roof of a government building located in Tangier, Morocco. The experimental data was recorded from 1st January 2015 to December 2015 based on real time observation. The aim is to encourage the use of solar PV system for government, commercial and residence building in Morocco based on the obtained results. The system is made up of 20 modules of 250 Wp and one inverter of 5 kW. The assessed parameters of the PV installation includes energy output, final yield, modules temperature, efficiency module, performance ratio (PR and others. The PV park supplied the grid with 6411.3 kWh during the year 2015. The final yield (Yf ranged from 1.96 to 6.42 kWh/kWp, the performance ratio (PR ranged from 58% to 98% and the annual capacity factor was found to be 14.84%. The final yield of PV installation is compared with other final yields of solar PV systems located at other places. Finally various power losses are given through a diagram loss.

Overview of the metropolitan France photovoltaic park connected to the grid at the end of June 2016

International Nuclear Information System (INIS)

2016-01-01

In this newsletter, Enerplan, the French association of solar energy professionals, analyses the recently published data from RTE, the French transmission system operator, and ERDF/Enedis, the French power grid manager, and makes a monthly review of the French photovoltaic park situation: evolution of the connected power, of the pending power and of new demands. Data are presented for metropolitan France only, both globally and at the regional scale

Challenges to Grid Synchronization of Single-Phase Grid-Connected Inverters in Zero-Voltage Ride-Through Operation

DEFF Research Database (Denmark)

Zhang, Zhen; Yang, Yongheng; Blaabjerg, Frede

2016-01-01

With the fast development in Photovoltaic (PV) technology, the relevant grid-connection requirements/standards are continuously being updated, and more challenges have been imposed on both single-phase and three-phase grid-connected PV systems. For instance, PV systems are currently required...... to remain connected under grid voltage sags (even zero voltage condition). In this case, much attention should be paid to the grid synchronization in such a way to properly ride-through grid faults. Thus, in this paper, the most commonly-used and recently-developed Phase Locked Loop (PLL) synchronization...... methods have been evaluated for single-phase grid-connected PV systems in the case of Zero-Voltage Ride-Through (ZVRT) operation. The performances of the prior-art PLL methods in response to zero voltage faults in terms of detection precision and dynamic response are assessed in this paper. Simulation...

A New Power Calculation Method for Single-Phase Grid-Connected Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede

2013-01-01

A new method to calculate average active power and reactive power for single-phase systems is proposed in this paper. It can be used in different applications where the output active power and reactive power need to be calculated accurately and fast. For example, a grid-connected photovoltaic...... system in low voltage ride through operation mode requires a power feedback for the power control loop. Commonly, a Discrete Fourier Transform (DFT) based power calculation method can be adopted in such systems. However, the DFT method introduces at least a one-cycle time delay. The new power calculation...... method, which is based on the adaptive filtering technique, can achieve a faster response. The performance of the proposed method is verified by experiments and demonstrated in a 1 kW single-phase grid-connected system operating under different conditions.Experimental results show the effectiveness...

Overview of the French photovoltaic park connected to the grid at the end of December 2015

International Nuclear Information System (INIS)

2016-01-01

In this newsletter, Enerplan, the French association of solar energy professionals, analyses the recently published data from RTE, the French transmission system operator, and ERDF/Enedis, the French power grid manager, and makes a monthly review of the French photovoltaic park situation: evolution of the connected power, of the pending power and of new demands. Data are presented for overall France as well as separately for metropolitan France and overseas territories, and also at the regional scale

Overview of the French photovoltaic park connected to the grid at the end of March 2016

International Nuclear Information System (INIS)

2016-01-01

In this newsletter, Enerplan, the French association of solar energy professionals, analyses the recently published data from RTE, the French transmission system operator, and ERDF/Enedis, the French power grid manager, and makes a monthly review of the French photovoltaic park situation: evolution of the connected power, of the pending power and of new demands. Data are presented for overall France as well as separately for metropolitan France and overseas territories, and also at the regional scale

Overview of the French photovoltaic park connected to the grid at the end of June 2015

International Nuclear Information System (INIS)

2015-01-01

In this newsletter, Enerplan, the French association of solar energy professionals, analyses the recently published data from RTE, the French transmission system operator, and ERDF/Enedis, the French power grid manager, and makes a monthly review of the French photovoltaic park situation: evolution of the connected power, of the pending power and of new demands. Data are presented for overall France as well as separately for metropolitan France and overseas territories, and also at the regional scale

A new procedure for estimating the cell temperature of a high concentrator photovoltaic grid connected system based on atmospheric parameters

International Nuclear Information System (INIS)

Fernández, Eduardo F.; Almonacid, Florencia

2015-01-01

Highlights: • Concentrating grid-connected systems are working at maximum power point. • The operating cell temperature is inherently lower than at open circuit. • Two novel methods for estimating the cell temperature are proposed. • Both predict the operating cell temperature from atmospheric parameters. • Experimental results show that both methods perform effectively. - Abstract: The working cell temperature of high concentrator photovoltaic systems is a crucial parameter when analysing their performance and reliability. At the same time, due to the special features of this technology, the direct measurement of the cell temperature is very complex and is usually obtained by using different indirect methods. High concentrator photovoltaic modules in a system are operating at maximum power since they are connected to an inverter. So that, their cell temperature is lower than the cell temperature of a module at open-circuit voltage since an important part of the light power density is converted into electricity. In this paper, a procedure for indirectly estimating the cell temperature of a high concentrator photovoltaic system from atmospheric parameters is addressed. Therefore, this new procedure has the advantage that is valid for estimating the cell temperature of a system at any location of interest if the atmospheric parameters are available. To achieve this goal, two different methods are proposed: one based on simple mathematical relationships and another based on artificial intelligent techniques. Results show that both methods predicts the cell temperature of a module connected to an inverter with a low margin of error with a normalised root mean square error lower or equal than 3.3%, an absolute root mean square error lower or equal than 2 °C, a mean absolute error lower or equal then 1.5 °C, and a mean bias error and a mean relative error almost equal to 0%

Simulation and performance analysis of 110 kWp grid-connected photovoltaic system for residential building in India: A comparative analysis of various PV technology

Directory of Open Access Journals (Sweden)

Akash Kumar Shukla

2016-11-01

Full Text Available System simulation is necessary to investigate the feasibility of Solar PV system at a given location. This study is done to evaluate the feasibility of grid connected rooftop solar photovoltaic system for a residential Hostel building at MANIT, Bhopal, India (Latitude: 23° 16′ N, Longitude: 77° 36′ E. The study focuses on the use of Solargis PV Planner software as a tool to analyze the performance a 110 kWp solar photovoltaic rooftop plant and also compares the performances of different PV technologies based on simulated energy yield and performance ratio. Solargis proves to easy, fast, accurate and reliable software tool for the simulation of solar PV system.

Regional Analysis of Aids and Prices for Small-scale Grid-connected Solar Photovoltaic Systems in Spain

International Nuclear Information System (INIS)

Varela, M.; Ramirez, L.; Mora, L.; Sidrach de Cardona, M.

2002-01-01

Electricity production from small solar photovoltaic systems in Spain obtains a premium pnce of 0,36 ε/kWh over the electricity market price or a fix price of 0,40 ε/kWh. The development of these small systems in Spain clearly demonstrates that the established prime is not sufficient in the majority of locations. On the other hand, the prime revision set up by the RD 2818/98, considering the profitability of the renewable installations, demand a regional analysis of small PV systems profitability necessary in Spain. The accomplished results permit to conclude that the amount of the current prime is by itself insufficient to make profitable the small grid-connected PV systems in anywhere of the national geography. To guarantee the profitability of these systems it should be necessary to place the fix price at around 0,93 ε/kWh. However, if the duplication of the current price obtained by these installations was considered, this could ensure the profitability of these small systems in at least the 77% of the land. (Author) 12 refs

A novel multi-model neuro-fuzzy-based MPPT for three-phase grid-connected photovoltaic system

Energy Technology Data Exchange (ETDEWEB)

Chaouachi, Aymen; Kamel, Rashad M.; Nagasaka, Ken [Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, Nakamachi (Japan)

2010-12-15

This paper presents a novel methodology for Maximum Power Point Tracking (MPPT) of a grid-connected 20 kW photovoltaic (PV) system using neuro-fuzzy network. The proposed method predicts the reference PV voltage guarantying optimal power transfer between the PV generator and the main utility grid. The neuro-fuzzy network is composed of a fuzzy rule-based classifier and three multi-layered feed forwarded Artificial Neural Networks (ANN). Inputs of the network (irradiance and temperature) are classified before they are fed into the appropriated ANN for either training or estimation process while the output is the reference voltage. The main advantage of the proposed methodology, comparing to a conventional single neural network-based approach, is the distinct generalization ability regarding to the nonlinear and dynamic behavior of a PV generator. In fact, the neuro-fuzzy network is a neural network based multi-model machine learning that defines a set of local models emulating the complex and nonlinear behavior of a PV generator under a wide range of operating conditions. Simulation results under several rapid irradiance variations proved that the proposed MPPT method fulfilled the highest efficiency comparing to a conventional single neural network and the Perturb and Observe (P and O) algorithm dispositive. (author)

Development of an Advanced Grid-Connected PV-ECS System Considering Solar Energy Estimation

Science.gov (United States)

Rahman, Md. Habibur; Yamashiro, Susumu; Nakamura, Koichi

In this paper, the development and the performance of a viable distributed grid-connected power generation system of Photovoltaic-Energy Capacitor System (PV-ECS) considering solar energy estimation have been described. Instead of conventional battery Electric Double Layer Capacitors (EDLC) are used as storage device and Photovoltaic (PV) panel to generate power from solar energy. The system can generate power by PV, store energy when the demand of load is low and finally supply the stored energy to load during the period of peak demand. To realize the load leveling function properly the system will also buy power from grid line when load demand is high. Since, the power taken from grid line depends on the PV output power, a procedure has been suggested to estimate the PV output power by calculating solar radiation. In order to set the optimum value of the buy power, a simulation program has also been developed. Performance of the system has been studied for different load patterns in different weather conditions by using the estimated PV output power with the help of the simulation program.

Design issues for grid-connected photovoltaic systems

Science.gov (United States)

Ropp, Michael Eugene

1998-08-01

Photovoltaics (PV) is the direct conversion of sunlight to electrical energy. In areas without centralized utility grids, the benefits of PV easily overshadow the present shortcomings of the technology. However, in locations with centralized utility systems, significant technical challenges remain before utility-interactive PV (UIPV) systems can be integrated into the mix of electricity sources. One challenge is that the needed computer design tools for optimal design of PV systems with curved PV arrays are not available, and even those that are available do not facilitate monitoring of the system once it is built. Another arises from the issue of islanding. Islanding occurs when a UIPV system continues to energize a section of a utility system after that section has been isolated from the utility voltage source. Islanding, which is potentially dangerous to both personnel and equipment, is difficult to prevent completely. The work contained within this thesis targets both of these technical challenges. In Task 1, a method for modeling a PV system with a curved PV array using only existing computer software is developed. This methodology also facilitates comparison of measured and modeled data for use in system monitoring. The procedure is applied to the Georgia Tech Aquatic Center (GTAC) FV system. In the work contained under Task 2, islanding prevention is considered. The existing state-of-the- art is thoroughly reviewed. In Subtask 2.1, an analysis is performed which suggests that standard protective relays are in fact insufficient to guarantee protection against islanding. In Subtask 2.2. several existing islanding prevention methods are compared in a novel way. The superiority of this new comparison over those used previously is demonstrated. A new islanding prevention method is the subject under Subtask 2.3. It is shown that it does not compare favorably with other existing techniques. However, in Subtask 2.4, a novel method for dramatically improving this new

Resonance Damping and Parameter Design Method for LCL-LC Filter Interfaced Grid-Connected Photovoltaic Inverters

DEFF Research Database (Denmark)

Li, Zipeng; Jiang, Aiting; Shen, Pan

2016-01-01

, this paper presents a systematic design method for the LCL-LC filtered grid-connected photovoltaic (PV) system. With this method, controller parameters and the active damping feedback coefficient are easily obtained by specifying the system stability and dynamic performance indices, and it is more convenient......-frequency harmonics attenuation ability, but the resonant problem affects the system stability remarkably. In this paper, active damping based on the capacitor voltage feedback is proposed using the concept of the equivalent virtual impedance in parallel with the capacitor. With the consideration of system delay...... to optimize the system performance according to the predefined satisfactory region. Finally, the simulation results are presented to validate the proposed design method and control scheme....

Integration of plug-in hybrid electric vehicles (PHEV) with grid connected residential photovoltaic energy systems

Science.gov (United States)

Nagarajan, Adarsh; Shireen, Wajiha

2013-06-01

This paper proposes an approach for integrating Plug-In Hybrid Electric Vehicles (PHEV) to an existing residential photovoltaic system, to control and optimize the power consumption of residential load. Control involves determining the source from which residential load will be catered, where as optimization of power flow reduces the stress on the grid. The system built to achieve the goal is a combination of the existing residential photovoltaic system, PHEV, Power Conditioning Unit (PCU), and a controller. The PCU involves two DC-DC Boost Converters and an inverter. This paper emphasizes on developing the controller logic and its implementation in order to accommodate the flexibility and benefits of the proposed integrated system. The proposed controller logic has been simulated using MATLAB SIMULINK and further implemented using Digital Signal Processor (DSP) microcontroller, TMS320F28035, from Texas Instruments

Research on a New Control Scheme of Photovoltaic Grid Power Generation System

Directory of Open Access Journals (Sweden)

Dong-Hui Li

2014-01-01

Full Text Available A new type of photovoltaic grid power generation system control scheme to solve the problems of the conventional photovoltaic grid power generation systems is presented. To aim at the oscillation and misjudgment of traditional perturbation observation method, an improved perturbation observation method comparing to the next moment power is proposed, combining with BOOST step-up circuit to realize the maximum power tracking. To counter the harmonic pollution problem in photovoltaic grid power generation system, the deadbeat control scheme in fundamental wave synchronous frequency rotating coordinate system of power grid is presented. A parameter optimization scheme based on positive feedback of active frequency shift island detection to solve the problems like the nondetection zone due to the import of disturbance in traditional island detection method is proposed. Finally, the results in simulation environment by MATLAB/Simulink simulation and experiment environment verify the validity and superiority of the proposed scheme.

Integration of electric vehicles with optimum sized storage for grid connected photo-voltaic system

OpenAIRE

Sulabh Sachan

2017-01-01

The necessity of energy storage by means of battery/EV is exceedingly expected in event of energy blackouts. Different advantages incorporate sparing the cash in purchasing top time power and support the grid when grid power is deficit against the load demand. In this paper, ideal size of energy storage in a grid associated photovoltaic (PV) framework is proposed. The methodology of energy flow choice is produced with the appraisal on accessibility of PV yield control and the load demand. The...

Optimum Design Of Grid Connected Photovoltaic System Using Concentrators

Directory of Open Access Journals (Sweden)

Eng. Mohammed Fawzy

2015-08-01

Full Text Available Abstract Due to the increasing demand of electrical energy in Egypt and also in many neighboring countries around the world the main problem facing electrical energy production using classical methods such steam power stations is the depletion of fossil fuels. The gap between the electrical energy demand and the continuous increase on the fossil fuel cost make the problem of electricity generation more sophisticated. With the continuous decrease of the photovoltaic PV technologies cost it doesnt make sense neglecting the importance of electricity production using solar photovoltaic PV especially that the annual average daily energy received is about 6 kamp12310whmamp123112day in Cairo Egypt 30N.In this work a detailed simulation model including photovoltaic PV module characteristics and climatic conditions of Cairo Egypt is developed. The model compares fixed PV systems electrical energy output with photovoltaic PV system using concentrators and double axis tracker systems. The comparison includes the energy generated area required as well as the cost per kwh generated. The optimality criterion is the cost per kwh generated. The system that gives the minimum cost per kwh is the optimum system. To verify the developed model the simulation results of fixed PV modules and CPV using tracking system obtained by the model are compared with practical measurements of 40KW peak station erected in Cairo Egypt 30N.Very good agreement between measured values and results obtained from detailed simulation model. For fixed PV system the detailed economic analysis showed that it gives minimum cost perkwh generated Comparisons among these systems are presented. For Cairo results showed that a cost of about 6 to 9 US centskwh is attainable.

Delta-Connected Cascaded H-Bridge Multilevel Converters for Large-Scale Photovoltaic Grid Integration

DEFF Research Database (Denmark)

Yu, Yifan; Konstantinou, Georgios; Townsend, Christopher D.

2017-01-01

The cascaded H-bridge (CHB) converter is becoming a promising candidate for use in next generation large-scale photovoltaic (PV) power plants. However, solar power generation in the three converter phase-legs can be significantly unbalanced, especially in a large geographically-dispersed plant....... The power imbalance between the three phases defines a limit for the injection of balanced three-phase currents to the grid. This paper quantifies the performance of, and experimentally confirms, the recently proposed delta-connected CHB converter for PV applications as an alternative configuration...... for large-scale PV power plants. The required voltage and current overrating for the converter is analytically developed and compared against the star-connected counterpart. It is shown that the delta-connected CHB converter extends the balancing capabilities of the star-connected CHB and can accommodate...

Techno-Economic Performance Evaluation for Olive Mills Powered by Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Ovidio Rabaza

2015-10-01

Full Text Available In recent years, due to the rise in petroleum prices and greenhouse gas emissions, renewable energy has been recommended as a power source for different types of facilities. For the period 2010 to 2020 the European Commission has established three key objectives related to climatic change and energy sustainability, such as reductions of CO2 emissions, increases in the use of renewable energy, and improvements in energy efficiency. A key industry is olive oil production in olive mills, where there is a great opportunity to reduce electricity consumption, increase additional profits related to the reduction of technologies that are harmful to the environment, and to cut back maintenance costs. For this reason, a feasibility study of grid-connected photovoltaics (PV systems has been carried out for different types of olive mills in Andalusia (southern Spain. This region is highly energy dependent, but has an abundance of “green” resources to be exploited. The results of this study contemplate a reduction in spending on electrical power of between 2% and 37%, and an increase in the use of renewable energy of between 2% and 26%. These results are according to the self-consumption or net metering policy and the production capacity of olive oil.

Harmonics Suppression for Single-Phase Grid-Connected Photovoltaic Systems in Different Operation Modes

DEFF Research Database (Denmark)

Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

2013-01-01

-connected PV inverters may be severely affected in different operation modes. In this paper, a detailed analysis is conducted to reveal the relationship between the harmonics level with the power factor and the current level in the PV systems. A current control solution which employs an Internal Model...... Principle (IMP) is proposed to suppress the harmonic currents injected into the grid. Experiments are carried out to verify the analysis and the performance of the proposed control method. It is demonstrated that the proposed method presents an effective solution to harmonics suppression for single......-phase grid-connected PV systems in different operation modes. Especially, it can remove higher order harmonics effectively leading to a better power quality compared to the Proportional plus Multi-Resonant Controller, and it has less computational burden....

The internal rate of return of photovoltaic grid-connected systems. A comprehensive sensitivity analysis

International Nuclear Information System (INIS)

Talavera, D.L.; Nofuentes, G.; Aguilera, J.

2010-01-01

At present, photovoltaic grid-connected systems (PVGCS) are experiencing a formidable market growth. This is mainly due to a continuous downward trend in PV cost together with some government support programmes launched by many developed countries. However, government bodies and prospective owners/investors are concerned with how changes in existing economic factors - financial incentives and main economic parameters of the PVGCS - that configure a given scenario may affect the profitability of the investment in these systems. Consequently, not only is a mere estimate of the economic profitability in a specific moment required, but also how this profitability may vary according to changes in the existing scenario. In order to enlighten decision-makers and prospective owners/investors of PVGCS, a sensitivity analysis of the internal rate of return (IRR) to some economic factors has been carried out. Three different scenarios have been assumed to represent the three top geographical markets for PV: the Euro area, the USA and Japan. The results obtained in this analysis provide clear evidence that annual loan interest, normalised initial investment subsidy, normalised annual PV electricity yield, PV electricity unitary price and normalised initial investment are ordered from the lowest to the highest impact on the IRR. A short and broad analysis concerning the taxation impact is also provided. (author)

Suggested Grid Code Modifications to Ensure Wide-Scale Adoption of Photovoltaic Energy in Distributed Power Generation Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Enjeti, Prasad; Blaabjerg, Frede

2013-01-01

Current grid standards seem to largely require low power (e.g. several kilowatts) single-phase photovoltaic (PV) systems to operate at unity power factor with maximum power point tracking, and disconnect from the grid under grid faults. However, in case of a wide-scale penetration of single......-phase PV systems in the distributed grid, the disconnection under grid faults can contribute to: a) voltage flickers, b) power outages, and c) system instability. In this paper, grid code modifications are explored for wide-scale adoption of PV systems in the distribution grid. More recently, Italy...... and Japan, have undertaken a major review of standards for PV power conversion systems connected to low voltage networks. In view of this, the importance of low voltage ride-through for single-phase PV power systems under grid faults along with reactive power injection is studied in this paper. Three...

Comparative Analysis of Inversors for Small PV Systems Grid Connected; Analisis Comparativo de inversores para la conexion a Red de Pequnos Sistemas Fotovoltaicos

Energy Technology Data Exchange (ETDEWEB)

Sidrach de Cardona, M.; Ramirez, L.

2001-07-01

The energy produced by a grid connected photovoltaic system is a function of weather conditions, mainly available radiation and temperature, photovoltaic array efficiency and inverter characteristics. The results obtained in experimental measurements with four small grid-connected inverters are described in this work. The main goal is to know the inverter performance in real operation conditions. For this purpose a 2 kW{sub p} photovoltaic system has been used. These results allow us to know both the inverter efficiency and its output power quality. The following parameters have been evaluated as a function of but put inverter power efficiency, point of maximum power tracking, intensity and voltage waveform, total harmonic distortion and harmonic values to 31 order, frequency, power factor and reactive power. Other interesting parameters like stand-by energy consumption and daily losses due to the inverter threshold have also been analyzed. the results allow us to know the inverter features as a function of its real work point. In our comparative study it is possible to observe remarkable differences between the inverters; these results show how important it is to have a unique standard for inverters to photovoltaic grid-connected systems. (Author)

An economic evaluation of photovoltaic grid connected systems (PVGCS) in Flanders for companies: A generic model

International Nuclear Information System (INIS)

Audenaert, Amaryllis; De Boeck, Liesje; De Cleyn, Sven; Lizin, Sebastien; Adam, Jean-Francois

2010-01-01

In this paper an economic evaluation of photovoltaic grid connected systems (PVGCS) for companies situated in Flanders (Belgium) is conducted by using a generic Excel model. The model is unique in that it includes the dimension of taxation. This inclusion is required, otherwise the fiscal benefit of using solar panels is not accounted for. The model uses the cash flow projection method. This technique allows the calculation of the following classical evaluation criteria: net present value, internal rate of return, payback period, discounted payback period, profitability index, yield unit cost, yield unit revenue and break-even turnkey cost. Their outcome makes it possible to answer the question whether installing a PVGCS in Flanders is a responsible financial investment for companies. Furthermore, the paper estimates whether the corporate environment is ready for a subsidy legislation change. This change has recently been announced and as such it is possible to gauge whether the current market situation is profitable given future legislation. (author)

Dynamics of voltage source converter in a grid connected solar photovoltaic system

DEFF Research Database (Denmark)

Haribabu, Divyanagalakshmi; Vangari, Adithya; Sakamuri, Jayachandra N.

2015-01-01

This paper emphasises the modelling and control of a voltage source converter (VSC) for three phase grid connected PV system. The transfer functions for inner current control and outer DC link voltage control for VSC are derived. The controllers for VSC are designed based on PI and K factor contr...

Islanding detection technique using wavelet energy in grid-connected PV system

Science.gov (United States)

Kim, Il Song

2016-08-01

This paper proposes a new islanding detection method using wavelet energy in a grid-connected photovoltaic system. The method detects spectral changes in the higher-frequency components of the point of common coupling voltage and obtains wavelet coefficients by multilevel wavelet analysis. The autocorrelation of the wavelet coefficients can clearly identify islanding detection, even in the variations of the grid voltage harmonics during normal operating conditions. The advantage of the proposed method is that it can detect islanding condition the conventional under voltage/over voltage/under frequency/over frequency methods fail to detect. The theoretical method to obtain wavelet energies is evolved and verified by the experimental result.

Modelling and Simulation of Grid Connected SPV System with Active Power Filtering Features

Science.gov (United States)

Saroha, Jaipal; Pandove, Gitanjali; Singh, Mukhtiar

2017-09-01

In this paper, the detailed simulation studies for a grid connected solar photovoltaic system (SPV) have been presented. The power electronics devices like DC-DC boost converter and grid interfacing inverter are most important components of proposed system. Here, the DC-DC boost converter is controlled to extract maximum power out of SPV under different irradiation levels, while the grid interfacing inverter is utilized to evacuate the active power and feed it into grid at synchronized voltage and frequency. Moreover, the grid interfacing inverter is also controlled to sort out the issues related to power quality by compensating the reactive power and harmonics current component of nearby load at point of common coupling. Besides, detailed modeling of various component utilized in proposed system is also presented. Finally, extensive simulations have been performed under different irradiation levels with various kinds of load to validate the aforementioned claims. The overall system design and simulation have been performed by using Sim Power System toolbox available in the library of MATLAB.

Grid-tied photovoltaic and battery storage systems with Malaysian electricity tariff

DEFF Research Database (Denmark)

Subramani, Gopinath; Ramachandaramurthy, Vigna K.; Padmanaban, Sanjeevikumar

2017-01-01

Under the current energy sector framework of electricity tariff in Malaysia, commercial and industrial customers are required to pay the maximum demand (MD) charge apart from the net consumption charges every month. The maximum demand charge will contribute up to 20% of the electricity bill......, and will hence result in commercial and industrial customers focussing on alternative energy supply to minimize the billing cost. This paper aims to review the technical assessment methods of a grid-connected solar photovoltaic (PV)-battery storage system-with respect to maximum demand shaving. An effective......, technical, and economic aspects of the solar PV-battery system and the Malaysian electricity tariff for commercial and industrial customers....

Development and Testing of the Glenn Research Center Visitor's Center Grid-Tied Photovoltaic Power System

Science.gov (United States)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) has developed, installed, and tested a 12 kW DC grid-tied photovoltaic (PV) power system at the GRC Visitor s Center. This system utilizes a unique ballast type roof mount for installing the photovoltaic panels on the roof of the Visitor s Center with no alterations or penetrations to the roof. The PV system has generated in excess of 15000 kWh since operation commenced in August 2008. The PV system is providing power to the GRC grid for use by all. Operation of the GRC Visitor s Center PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provides valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the GRC Visitor s Center PV system, additional PV power system expansion at GRC is under consideration. The GRC Visitor s Center grid-tied PV power system was successfully designed and developed which served to validate the basic principles

S4 Grid-Connected Single-Phase Transformerless Inverter for PV Application

DEFF Research Database (Denmark)

Ardashir, Jaber Fallah; Siwakoti, Yam Prasad; Sabahi, Mehran

2016-01-01

This paper introduces a new single-phase transformerless inverter for grid-connected photovoltaic systems with low leakage current. It consists of four power switches, two diodes, two capacitors and a filter at the output stage. The neutral of the grid is directly connected to the negative terminal...... size, low cost, flexible grounding configuration and higher efficiency. The operating principle and analysis of the proposed circuit are presented in details. Experimental results of a 500 W prototype are demonstrated to validate the proposed topology and the overall concept. The results obtained...... clearly verify the performance of the proposed inverter and its practical application for grid-connected PV systems....

Flexible Power Control of Photovoltaic Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Sangwongwanich, Ariya; Yang, Yongheng

2018-01-01

With a still increasing penetration level of grid-connected photovoltaic (PV) systems, more advanced and flexible control functionalities are demanded. To ensure a smooth and friendly integration between the PV systems and the grid, the power generated by the PV system needs to be flexible...

A novel off-grid hybrid power system comprised of solar photovoltaic, wind, and hydro energy sources

International Nuclear Information System (INIS)

Bhandari, Binayak; Lee, Kyung-Tae; Lee, Caroline Sunyong; Song, Chul-Ki; Maskey, Ramesh K.; Ahn, Sung-Hoon

2014-01-01

Highlights: • We propose two hybridization methods for small off-grid power systems consisting solar (PV), wind, and micro-hydro sources. • One of the methods was implemented in a mini-grid connecting Thingan and Kolkhop villages in Makawanpur District, Nepal. • The results can be applied to help achieve Millennium Development Goal 7: Ensuring environmental sustainability. • This is the first implementation anywhere comprising of three renewable energy power, in a single off-grid power system. • This research may be applied as a practical guide for implementing similar systems in various locations. - Abstract: Several factors must be considered before adopting a full-phase power generation system based on renewable energy sources. Long-term necessary data (for one year if possible) should be collected before making any decisions concerning implementation of such a systems. To accurately assess the potential of available resources, we measured solar irradiation, wind speed, and ambient temperature at two high-altitude locations in Nepal: the Lama Hotel in Rasuwa District and Thingan in Makawanpur District. Here, we propose two practical, economical hybridization methods for small off-grid systems consisting entirely of renewable energy sources—specifically solar photovoltaic (PV), wind, and micro-hydro sources. One of the methods was tested experimentally, and the results can be applied to help achieve Millennium Development Goal 7: Ensuring environmental sustainability. Hydro, wind, and solar photovoltaic energy are the top renewable energy sources in terms of globally installed capacity. However, no reports have been published about off-grid hybrid systems comprised of all three sources, making this implementation the first of its kind anywhere. This research may be applied as a practical guide for implementing similar systems in various locations. Of the four off-grid PV systems installed by the authors for village electrification in Nepal, one was

GRS - Guarantee of results for grid-connected solar photovoltaic systems; GRS - Garantierte Resultate von Solarstromanlagen

Energy Technology Data Exchange (ETDEWEB)

Meier, Ch.; Frei, R.

2001-07-01

This final report for the Swiss Federal Office of Energy describes the development of a performance guarantee for the power delivered by grid-connected photovoltaic (PV) power plant. This is important for investors, who need to be able to calculate the price of the energy produced by the PV plant. The report examines the results of various case studies and experience gained with GRS contracts developed in different countries including Switzerland, the Netherlands, France and Germany. The problems encountered, which provided feedback for the further development of the contract presented in the report, are discussed. The model contract, which proposes a framework which provides many possible variations and adaptations, is presented in detail. Various problem areas such as guaranteed energy yield, meteorological references, correction methods, failure detection, dispute settlement and many other points are covered.

A practical technique for on-line monitoring of a photovoltaic plant connected to a single-phase grid

International Nuclear Information System (INIS)

Yahyaoui, Imene; Segatto, Marcelo E.V.

2017-01-01

Highlights: • Automatic detection of main faults in PV systems is presented and tested. • Specific indicators detect bypass module, open-circuit string and partial shading. • The strategy efficiency is validated by experiments for two days. • The strategy allows the number of faulty PV modules and strings to be determined. • The method is effective and minimizes the use of sensors in the monitoring system. - Abstract: Improving the reliability and enhancing the performance of photovoltaic (PV) plants are important objectives that increase the competitiveness of the PV systems, especially for grid connected PV plants, for which, every kilowatt-hour is crucial, since only kilowatt-hours that are fed into the grid are remunerated. Therefore, monitoring and automatic faults detection during the PV panels operation are necessary to ensure the optimal use of the energy generated by the PV plant, and to provide a reliable power supply. In this research paper, two current and voltage indicators are used to analyze and to distinguish, in real-time, the faults related to bypassed PV modules, open-circuits strings and partial shading for a PV plant connected to a single-phase grid. Moreover, the presented strategy allows determining the total number of faulty PV modules and/or strings. The efficiencies of these indicators are tested by experiments, using a Control and Data Acquisition System, which proved the effectiveness of the proposed approach.

High-Speed Monitoring of Multiple Grid-Connected Photovoltaic Array Configurations and Supplementary Weather Station.

Science.gov (United States)

Boyd, Matthew T

2017-06-01

Three grid-connected monocrystalline silicon photovoltaic arrays have been instrumented with research-grade sensors on the Gaithersburg, MD campus of the National Institute of Standards and Technology (NIST). These arrays range from 73 kW to 271 kW and have different tilts, orientations, and configurations. Irradiance, temperature, wind, and electrical measurements at the arrays are recorded, and images are taken of the arrays to monitor shading and capture any anomalies. A weather station has also been constructed that includes research-grade instrumentation to measure all standard meteorological quantities plus additional solar irradiance spectral bands, full spectrum curves, and directional components using multiple irradiance sensor technologies. Reference photovoltaic (PV) modules are also monitored to provide comprehensive baseline measurements for the PV arrays. Images of the whole sky are captured, along with images of the instrumentation and reference modules to document any obstructions or anomalies. Nearly, all measurements at the arrays and weather station are sampled and saved every 1s, with monitoring having started on Aug. 1, 2014. This report describes the instrumentation approach used to monitor the performance of these photovoltaic systems, measure the meteorological quantities, and acquire the images for use in PV performance and weather monitoring and computer model validation.

Cost and Performance Model for Photovoltaic Systems

Science.gov (United States)

Borden, C. S.; Smith, J. H.; Davisson, M. C.; Reiter, L. J.

1986-01-01

Lifetime cost and performance (LCP) model assists in assessment of design options for photovoltaic systems. LCP is simulation of performance, cost, and revenue streams associated with photovoltaic power systems connected to electric-utility grid. LCP provides user with substantial flexibility in specifying technical and economic environment of application.

Integration of electric vehicles with optimum sized storage for grid connected photo-voltaic system

Directory of Open Access Journals (Sweden)

Sulabh Sachan

2017-12-01

Full Text Available The necessity of energy storage by means of battery/EV is exceedingly expected in event of energy blackouts. Different advantages incorporate sparing the cash in purchasing top time power and support the grid when grid power is deficit against the load demand. In this paper, ideal size of energy storage in a grid associated photovoltaic (PV framework is proposed. The methodology of energy flow choice is produced with the appraisal on accessibility of PV yield control and the load demand. The energy flow decision is changed by peak and off peak hours to shorten the functional cost of the grid associated PV framework with storage. Naturally, the quantities of electric vehicles that can be associated are resolved.

A Review on Current Reference Calculation of Three-Phase Grid-Connected PV Converters under Grid Faults

DEFF Research Database (Denmark)

Afshari, Ehsan; Moradi, Gholam Reza; Yang, Yongheng

2017-01-01

Unbalanced grid voltage dips may lead to unbalanced non-sinusoidal current injections, dc-link voltage oscillations, and active and/or reactive power oscillations with twice the grid fundamental frequency in three-phase grid-connected Photovoltaic (PV) systems. Double grid frequency oscillations...... of the most important issues that should be coped with for a reliable operation of grid-connected converters under unbalanced grid faults. Accordingly, this paper reviews the existing CRC methods and presents a current reference generation method, which can have 16 unique modes. Issues are also investigated...... at the dc-link of the conventional two-stage PV inverters can further deteriorate the dc-link capacitor, which is one of the most life-limiting components in the system. Proper controls of these converters may efficiently address this problem. In those solutions, Current Reference Calculation (CRC) is one...

A Unified Current Loop Tuning Approach for Grid-Connected Photovoltaic Inverters

Directory of Open Access Journals (Sweden)

Weiyi Zhang

2016-09-01

Full Text Available High level penetration of renewable energy sources has reshaped modern electrical grids. For the future grid, distributed renewable power generation plants can be integrated in a larger scale. Control of grid-connected converters is required to achieve fast power reference tracking and further to present grid-supporting and fault ride-through performance. Among all of the aspects for converter control, the inner current loop for grid-connected converters characterizes the system performance considerably. This paper proposes a unified current loop tuning approach for grid-connected converters that is generally applicable in different cases. A direct discrete-time domain tuning procedure is used, and particularly, the selection of the phase margin and crossover frequency is analyzed, which acts as the main difference compared with the existing studies. As a general method, the approximation in the modeling of the controller and grid filter is avoided. The effectiveness of the tuning approach is validated in both simulation and experimental results with respect to power reference tracking, frequency and voltage supporting.

Comparison of measured and predicted long term performance of grid a connected photovoltaic system

International Nuclear Information System (INIS)

Mondol, Jayanta Deb; Yohanis, Yigzaw G.; Norton, Brian

2007-01-01

Predicted performance of a grid connected photovoltaic (PV) system using TRNSYS was compared with measured data. A site specific global-diffuse correlation model was developed and used to calculate the beam and diffuse components of global horizontal insolation. A PV module temperature equation and a correlation relating input and output power of an inverter were developed using measured data and used in TRNSYS to perform PV array and inverter outputs simulation. Different combinations of the tilted surface radiation model, global-diffuse correlation model and PV module temperature equation were used in the simulations. Statistical error analysis was performed to compare the results for each combination. The simulation accuracy was improved by using the new global-diffuse correlation and module temperature equation in the TRNSYS simulation. For an isotropic sky tilted surface radiation model, the average monthly difference between measured and predicted PV output before and after modification of the TRNSYS component were 10.2% and 3.3%, respectively, and, for an anisotropic sky model, 15.4% and 10.7%, respectively. For inverter output, the corresponding errors were 10.4% and 3.3% and 15.8% and 8.6%, respectively. Measured PV efficiency, overall system efficiency, inverter efficiency and performance ratio of the system were compared with the predicted results. The predicted PV performance parameters agreed more closely with the measured parameters in summer than in winter. The difference between predicted performances using an isotropic and an anisotropic sky tilted surface models is between 1% and 2%

A Wavelet-Based Unified Power Quality Conditioner to Eliminate Wind Turbine Non-Ideality Consequences on Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Bijan Rahmani

2016-05-01

Full Text Available The integration of renewable power sources with power grids presents many challenges, such as synchronization with the grid, power quality problems and so on. The shunt active power filter (SAPF can be a solution to address the issue while suppressing the grid-end current harmonics and distortions. Nonetheless, available SAPFs work somewhat unpredictably in practice. This is attributed to the dependency of the SAPF controller on nonlinear complicated equations and two distorted variables, such as load current and voltage, to produce the current reference. This condition will worsen when the plant includes wind turbines which inherently produce 3rd, 5th, 7th and 11th voltage harmonics. Moreover, the inability of the typical phase locked loop (PLL used to synchronize the SAPF reference with the power grid also disrupts SAPF operation. This paper proposes an improved synchronous reference frame (SRF which is equipped with a wavelet-based PLL to control the SAPF, using one variable such as load current. Firstly the fundamental positive sequence of the source voltage, obtained using a wavelet, is used as the input signal of the PLL through an orthogonal signal generator process. Then, the generated orthogonal signals are applied through the SRF-based compensation algorithm to synchronize the SAPF’s reference with power grid. To further force the remained uncompensated grid current harmonics to pass through the SAPF, an improved series filter (SF equipped with a current harmonic suppression loop is proposed. Concurrent operation of the improved SAPF and SF is coordinated through a unified power quality conditioner (UPQC. The DC-link capacitor of the proposed UPQC, used to interconnect a photovoltaic (PV system to the power grid, is regulated by an adaptive controller. Matlab/Simulink results confirm that the proposed wavelet-based UPQC results in purely sinusoidal grid-end currents with total harmonic distortion (THD = 1.29%, which leads to high

Stability analysis of grid inverter LCL-filter resonance in wind or photovoltaic parks

DEFF Research Database (Denmark)

Arcuri, S.; Liserre, M.; Ricchiuto, D.

2011-01-01

Typically the resonance problems related to the use of LCL-filters in grid connected inverters are analyzed assuming the operation of a single inverter. Wind and photovoltaic parks may experience propagation of resonance from a poorly damped inverter to other systems connected in parallel....... The paper focuses on the study of the resonance at a park system level with simulations and experimental results....

The photovoltaic energy market after 2000. Market survey and segmentation of and stimulation tools for the grid-connected photovoltaic energy market in the Netherlands after the year 2000

International Nuclear Information System (INIS)

Koot, E.J.; Middelkoop, D.J.

2000-01-01

As a preparation to a new photovoltaic covenant for the period 2001-2007 the Photovoltaic (PV) Steering Group ordered Ekomation to map the market potential (in Megawatt) for grid-connected PV systems of the most important market segments in the Netherlands. Two workshops were organized in which the most important parties (both supply-side and demand-side of the market) were involved in the discussion on the desired market strategy up to the year 2007, the most important market segments and the tools, required for market development. Results of the quantitative and qualitative market survey and the workshops are presented and discussed in this report. 20 refs

Feasibility Study of Grid Connected PV-Biomass Integrated Energy System in Egypt

Science.gov (United States)

Barakat, Shimaa; Samy, M. M.; Eteiba, Magdy B.; Wahba, Wael Ismael

2016-10-01

The aim of this paper is to present a feasibility study of a grid connected photovoltaic (PV) and biomass Integrated renewable energy (IRE) system providing electricity to rural areas in the Beni Suef governorate, Egypt. The system load of the village is analyzed through the environmental and economic aspects. The model has been designed to provide an optimal system configuration based on daily data for energy availability and demands. A case study area, Monshaet Taher village (29° 1' 17.0718"N, 30° 52' 17.04"E) is identified for economic feasibility in this paper. HOMER optimization model plan imputed from total daily load demand, 2,340 kWh/day for current energy consuming of 223 households with Annual Average Insolation Incident on a Horizontal Surface of 5.79 (kWh/m2/day) and average biomass supplying 25 tons / day. It is found that a grid connected PV-biomass IRE system is an effective way of emissions reduction and it does not increase the investment of the energy system.

Reactive Power Injection Strategies for Single-Phase Photovoltaic Systems Considering Grid Requirements

DEFF Research Database (Denmark)

Yang, Yongheng; Wang, Huai; Blaabjerg, Frede

2014-01-01

As the development and installation of photovoltaic (PV) systems are still growing at an exceptionally rapid pace, relevant grid integration policies are going to change consequently in order to accept more PV systems in the grid. The next generation PV systems will play an even more active role...

Simulation of Photovoltaic generator Connected To a Grid

Directory of Open Access Journals (Sweden)

F. Slama

2014-03-01

Full Text Available This paper presents the mathematical and the total Matlab-simulink model of the various components, of the photovoltaic power station connected to a network, (PSCN, namely the model of the photovoltaic generator. It is a comprehensive behavioural study which performed according to varying conditions of solar insulation and temperature. The photovoltaic generator and the inverter of single-phase current are modeled. The former by using a mathematical model that gives the values of maximum power according to the variation of the weather conditions, and the latter by a source of voltage controlled by voltage in order to inject a sinusoidal current and to estimate or predict the energy injected monthly or annually into the network.

LVRT Capability of Single-Phase Grid-Connected HERIC Inverter in PV Systems by a Look-up Table Based Predictive Control

DEFF Research Database (Denmark)

Zangeneh Bighash, Esmaeil; Sadeghzadeh, Seyed Mohammad; Ebrahimzadeh, Esmaeil

2017-01-01

Nowadays capacity of the photovoltaic systems in the grid is remarkable and provides a major part of energy in the grid. Therefore, an abruption of these systems from the grid can create a damage to the grid. Unlike in the past that PV systems disconnected from the grid when a voltage drop occurred......, nowadays these systems should have Low Voltage Ride-Through (LVRT) capability. The PV system should stay connected to the grid at fault time and help to recover the grid voltage by injecting the reactive power like in a power plant or a custom power device. There are two important factors for single phase...... grid connected PV inverters. The first one is the structure of the inverter and the second one is the control part. In this regard, the HERIC inverter can be a good selection among the transformerless inverters for a PV system due to its high efficiency. For the control part, this paper presents a look...

Application of Fuzzy Control in a Photovoltaic Grid-Connected Inverter

Directory of Open Access Journals (Sweden)

Zhaohong Zheng

2018-01-01

Full Text Available To realize the maximum power output of a grid-connected inverter, the MPPT (maximum power point tracking control method is needed. The perturbation and observation (P&O method can cause the inverter operating point to oscillate near the maximum power. In this paper, the fuzzy control P&O method is proposed, and the fuzzy control algorithm is applied to the disturbance observation method. The simulation results of the P&O method with fuzzy control and the traditional P&O method prove that not only can the new method reduce the power loss caused by inverter oscillation during maximum power point tracking, but also it has the advantage of speed. Inductive loads in the post-grid-connected stage cause grid-connected current distortion. A fuzzy control algorithm is added to the traditional deadbeat grid-connected control method to improve the quality of the system’s grid-connected operation. The fuzzy deadbeat control method is verified by experiments, and the harmonic current of the grid-connected current is less than 3%.

Multiple low frequency dual reference PWM control of a grid connected photovoltaic three phase NPC inverter with DC/DC boost converter

Directory of Open Access Journals (Sweden)

Mechouma Rabiaa

2014-01-01

Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.

A Grid Connected Photovoltaic Inverter with Battery-Supercapacitor Hybrid Energy Storage.

Science.gov (United States)

Miñambres-Marcos, Víctor Manuel; Guerrero-Martínez, Miguel Ángel; Barrero-González, Fermín; Milanés-Montero, María Isabel

2017-08-11

The power generation from renewable power sources is variable in nature, and may contain unacceptable fluctuations, which can be alleviated by using energy storage systems. However, the cost of batteries and their limited lifetime are serious disadvantages. To solve these problems, an improvement consisting in the collaborative association of batteries and supercapacitors has been studied. Nevertheless, these studies don't address in detail the case of residential and large-scale photovoltaic systems. In this paper, a selected combined topology and a new control scheme are proposed to control the power sharing between batteries and supercapacitors. Also, a method for sizing the energy storage system together with the hybrid distribution based on the photovoltaic power curves is introduced. This innovative contribution not only reduces the stress levels on the battery, and hence increases its life span, but also provides constant power injection to the grid during a defined time interval. The proposed scheme is validated through detailed simulation and experimental tests.

A Grid Connected Photovoltaic Inverter with Battery-Supercapacitor Hybrid Energy Storage

Science.gov (United States)

Guerrero-Martínez, Miguel Ángel; Barrero-González, Fermín

2017-01-01

The power generation from renewable power sources is variable in nature, and may contain unacceptable fluctuations, which can be alleviated by using energy storage systems. However, the cost of batteries and their limited lifetime are serious disadvantages. To solve these problems, an improvement consisting in the collaborative association of batteries and supercapacitors has been studied. Nevertheless, these studies don’t address in detail the case of residential and large-scale photovoltaic systems. In this paper, a selected combined topology and a new control scheme are proposed to control the power sharing between batteries and supercapacitors. Also, a method for sizing the energy storage system together with the hybrid distribution based on the photovoltaic power curves is introduced. This innovative contribution not only reduces the stress levels on the battery, and hence increases its life span, but also provides constant power injection to the grid during a defined time interval. The proposed scheme is validated through detailed simulation and experimental tests. PMID:28800102

On the design of product integrated photovoltaic systems

NARCIS (Netherlands)

Reich, N.H.

2010-01-01

With photovoltaic (PV) systems it is possible to create electricity generation systems for a wide range of purposes, of literally any size (microwatts to gigawatts). Solar cells deployed in large scale, grid-connected PV systems may energize millions of electric appliances connected by a utility

Adaptive fuzzy sliding control of single-phase PV grid-connected inverter.

Science.gov (United States)

Fei, Juntao; Zhu, Yunkai

2017-01-01

In this paper, an adaptive fuzzy sliding mode controller is proposed to control a two-stage single-phase photovoltaic (PV) grid-connected inverter. Two key technologies are discussed in the presented PV system. An incremental conductance method with adaptive step is adopted to track the maximum power point (MPP) by controlling the duty cycle of the controllable power switch of the boost DC-DC converter. An adaptive fuzzy sliding mode controller with an integral sliding surface is developed for the grid-connected inverter where a fuzzy system is used to approach the upper bound of the system nonlinearities. The proposed strategy has strong robustness for the sliding mode control can be designed independently and disturbances can be adaptively compensated. Simulation results of a PV grid-connected system verify the effectiveness of the proposed method, demonstrating the satisfactory robustness and performance.

Hosting Capacity of Solar Photovoltaics in Distribution Grids under Different Pricing Schemes

DEFF Research Database (Denmark)

Carollo, Riccardo; Chaudhary, Sanjay Kumar; Pillai, Jayakrishnan Radhakrishna

2015-01-01

Most of the solar photovoltaic (SPV) installations are connected to distribution networks. The majority of these systems are represented by single-phase rooftop SPVs connected to residential low voltage (LV) grids. The large SPV shares lead to grid integration issues such as voltage rise....... The results show that with the present TOU tariffs the EV integration in LV networks does not ease the grid bottlenecks for large PV penetration. Under the Net metering and DLMP the EV integration in LV grids tend to increase the PV hosting capacity......., overloading of the network components, voltage phase unbalance etc. A rapid expansion of Electric Vehicles (EVs) technology is estimated, whose connection is also expected to take place in the LV networks. EVs might represent a possible solution to the SPV integration issues as they can be used as fast...

EMISSIONS REDUCTION DATA FOR GRID-CONNECTED PHOTOVOLTAIC POWER SYSTEMS

Science.gov (United States)

This study measured the pollutant emission reduction potential of 29 photovoltaic (PV) systems installed on residential and commercial building rooftops across the U.S. from 1993 through 1997. The U.S. Environmental Protection Agency (EPA) and 21 electric power companies sponsor...

Fuzzy logic, PSO based fuzzy logic algorithm and current controls comparative for grid-connected hybrid system

Science.gov (United States)

Borni, A.; Abdelkrim, T.; Zaghba, L.; Bouchakour, A.; Lakhdari, A.; Zarour, L.

2017-02-01

In this paper the model of a grid connected hybrid system is presented. The hybrid system includes a variable speed wind turbine controlled by aFuzzy MPPT control, and a photovoltaic generator controlled with PSO Fuzzy MPPT control to compensate the power fluctuations caused by the wind in a short and long term, the inverter currents injected to the grid is controlled by a decoupled PI current control. In the first phase, we start by modeling of the conversion system components; the wind system is consisted of a turbine coupled to a gearless permanent magnet generator (PMG), the AC/DC and DC-DC (Boost) converter are responsible to feed the electric energy produced by the PMG to the DC-link. The solar system consists of a photovoltaic generator (GPV) connected to a DC/DC boost converter controlled by a PSO fuzzy MPPT control to extract at any moment the maximum available power at the GPV terminals, the system is based on maximum utilization of both of sources because of their complementary. At the end. The active power reached to the DC-link is injected to the grid through a DC/AC inverter, this function is achieved by controlling the DC bus voltage to keep it constant and close to its reference value, The simulation studies have been performed using Matlab/Simulink. It can be concluded that a good control system performance can be achieved.

The performance and economical analysis of grid-connected photovoltaic systems in Daegu, Korea

International Nuclear Information System (INIS)

Kim, Ju-Young; Jeon, Gyu-Yeob; Hong, Won-Hwa

2009-01-01

The distribution of the photovoltaic systems is faced with technological and economic problems, and the businesses and corporations feel burdened by the photovoltaic system's dubious economic value and high construction costs. Thus, not too many enterprises or private citizens have been participating in the business of installing photovoltaic systems. Moreover, because of lack of skills in integrating engineering and architectural design, they are experiencing difficulties even in using the technologies that have already been developed and available for application. To provide the basic information and specific data required for making the guidelines for developing photovoltaic technologies, this paper evaluates the system types, the actual state of operation, and performance of the two photovoltaic systems that are installed in Kiemyung University's Osan Building and Dongho Elementary School in Daegu Metropolitan City

Conditions and costs for renewables electricity grid connection: Examples in Europe

International Nuclear Information System (INIS)

Swider, Derk J.; Beurskens, Luuk; Davidson, Sarah; Twidell, John; Pyrko, Jurek; Prueggler, Wolfgang; Auer, Hans; Vertin, Katarina; Skema, Romualdas

2008-01-01

This paper compares conditions and costs for RES-E grid connection in selected European countries. These are Germany, the Netherlands, the United Kingdom, Sweden, Austria, Lithuania and Slovenia. Country specific case studies are presented for wind onshore and offshore, biomass and photovoltaic power systems, as based on literature reviews and stakeholder interviews. It is shown that, especially for wind offshore, the allocation of grid connection costs can form a significant barrier for the installation of new RES-E generation if the developer has to bear all such costs. If energy policy makers want to reduce the barriers for new large-scale RES-E deployment, then it is concluded that the grid connection costs should be covered by the respective grid operator. These costs may then be recouped by increasing consumer tariffs for the use of the grid. (author)

Stability of Grid-Connected PV Inverters with Large Grid Impedance Variation

DEFF Research Database (Denmark)

Liserre, Marco; Teodorescu, Remus; Blaabjerg, Frede

2004-01-01

Photovoltaic (PV) inverters used in dispersed power generation of houses in the range of 1-5 kW are currently available from several manufactures. However, large grid impedance variation is challenging the control and the grid filter design in terms of stability. In fact the PV systems are well...... suited for loads connected in a great distance to the transformer (long wires) and the situation becomes even more difficult in low-developed remote areas characterized by low power transformers and long distribution wires with high grid impedance. Hence a theoretical analysis is needed because the grid...... impedance variation leads to dynamic and stability problems both in the low frequency range (around the current controller bandwidth frequency) as well as in the high frequency range (around the LCL-filter resonance frequency). In the low frequency range the possible variation of the impedance challenges...

Lyapunov-Based Control Scheme for Single-Phase Grid-Connected PV Central Inverters

NARCIS (Netherlands)

Meza, C.; Biel, D.; Jeltsema, D.; Scherpen, J. M. A.

A Lyapunov-based control scheme for single-phase single-stage grid-connected photovoltaic central inverters is presented. Besides rendering the closed-loop system globally stable, the designed controller is able to deal with the system uncertainty that depends on the solar irradiance. A laboratory

Control strategy of grid-connected photovoltaic generation system based on GMPPT method

Science.gov (United States)

Wang, Zhongfeng; Zhang, Xuyang; Hu, Bo; Liu, Jun; Li, Ligang; Gu, Yongqiang; Zhou, Bowen

2018-02-01

There are multiple local maximum power points when photovoltaic (PV) array runs under partial shading condition (PSC).However, the traditional maximum power point tracking (MPPT) algorithm might be easily trapped in local maximum power points (MPPs) and cannot find the global maximum power point (GMPP). To solve such problem, a global maximum power point tracking method (GMPPT) is improved, combined with traditional MPPT method and particle swarm optimization (PSO) algorithm. Under different operating conditions of PV cells, different tracking algorithms are used. When the environment changes, the improved PSO algorithm is adopted to realize the global optimal search, and the variable step incremental conductance (INC) method is adopted to achieve MPPT in optimal local location. Based on the simulation model of the PV grid system built in Matlab/Simulink, comparative analysis of the tracking effect of MPPT by the proposed control algorithm and the traditional MPPT method under the uniform solar condition and PSC, validate the correctness, feasibility and effectiveness of the proposed control strategy.

The performance of Dutch photovoltaic inverters in areas with low grid voltage. A preliminary study

International Nuclear Information System (INIS)

Van Twisk, J.; Van der Borg, N.J.C.M.; Groeman, J.F.

2000-08-01

An important component of grid-connected photovoltaic (PV) systems is the inverter. The inverter must be suitable for the expected characteristics of the input of the photovoltaic panels and for the expected characteristics of the output of the electricity network. The characteristics of the electric grid in potential markets for Dutch inverter manufacturers can differ from the characteristics of Dutch electric grids. A preliminary study has been carried out to determine the characteristics of relevant power distribution systems and the expected effects of those networks on PV-inverters. It is concluded that the following characteristics need further study: voltage level (nominal voltage and long-lasting deviations of that level); transient overvoltages, harmonic components in the voltage, and direct current component. 5 refs

A feasibility study of stationary and dual-axis tracking grid-connected photovoltaic systems in the Upper Midwest

Science.gov (United States)

Warren, Ryan Duwain

Three primary objectives were defined for this work. The first objective was to determine, assess, and compare the performance, heat transfer characteristics, economics, and feasibility of real-world stationary and dual-axis tracking grid-connected photovoltaic (PV) systems in the Upper Midwest. This objective was achieved by installing two grid-connected PV systems with different mounting schemes in central Iowa, implementing extensive data acquisition systems, monitoring operation of the PV systems for one full year, and performing detailed experimental performance and economic studies. The two PV systems that were installed, monitored, and analyzed included a 4.59 kWp roof-mounted stationary system oriented for maximum annual energy production, and a 1.02 kWp pole-mounted actively controlled dual-axis tracking system. The second objective was to demonstrate the actual use and performance of real-world stationary and dual-axis tracking grid-connected PV systems used for building energy generation applications. This objective was achieved by offering the installed PV systems to the public for demonstration purposes and through the development of three computer-based tools: a software interface that has the ability to display real-time and historical performance and meteorological data of both systems side-by-side, a software interface that shows real-time and historical video and photographs of each system, and a calculator that can predict performance and economics of stationary and dual-axis tracking grid-connected PV systems at various locations in the United States. The final objective was to disseminate this work to social, professional, scientific, and academic communities in a way that is applicable, objective, accurate, accessible, and comprehensible. This final objective will be addressed by publishing the results of this work and making the computer-based tools available on a public website (www.energy.iastate.edu/Renewable/solar). Detailed experimental

Rapid Active Power Control of Photovoltaic Systems for Grid Frequency Support

Energy Technology Data Exchange (ETDEWEB)

Hoke, Anderson; Shirazi, Mariko; Chakraborty, Sudipta; Muljadi, Eduard; Maksimovic, Dragan

2017-01-01

As deployment of power electronic coupled generation such as photovoltaic (PV) systems increases, grid operators have shown increasing interest in calling on inverter-coupled generation to help mitigate frequency contingency events by rapidly surging active power into the grid. When responding to contingency events, the faster the active power is provided, the more effective it may be for arresting the frequency event. This paper proposes a predictive PV inverter control method for very fast and accurate control of active power. This rapid active power control method will increase the effectiveness of various higher-level controls designed to mitigate grid frequency contingency events, including fast power-frequency droop, inertia emulation, and fast frequency response, without the need for energy storage. The rapid active power control method, coupled with a maximum power point estimation method, is implemented in a prototype PV inverter connected to a PV array. The prototype inverter's response to various frequency events is experimentally confirmed to be fast (beginning within 2 line cycles and completing within 4.5 line cycles of a severe test event) and accurate (below 2% steady-state error).

Augmented Nonlinear Controller for Maximum Power-Point Tracking with Artificial Neural Network in Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Suliang Ma

2016-11-01

Full Text Available Photovoltaic (PV systems have non-linear characteristics that generate maximum power at one particular operating point. Environmental factors such as irradiance and temperature variations greatly affect the maximum power point (MPP. Diverse offline and online techniques have been introduced for tracking the MPP. Here, to track the MPP, an augmented-state feedback linearized (AFL non-linear controller combined with an artificial neural network (ANN is proposed. This approach linearizes the non-linear characteristics in PV systems and DC/DC converters, for tracking and optimizing the PV system operation. It also reduces the dependency of the designed controller on linearized models, to provide global stability. A complete model of the PV system is simulated. The existing maximum power-point tracking (MPPT and DC/DC boost-converter controller techniques are compared with the proposed ANN method. Two case studies, which simulate realistic circumstances, are presented to demonstrate the effectiveness and superiority of the proposed method. The AFL with ANN controller can provide good dynamic operation, faster convergence speed, and fewer operating-point oscillations around the MPP. It also tracks the global maxima under different conditions, especially irradiance-mutating situations, more effectively than the conventional methods. Detailed mathematical models and a control approach for a three-phase grid-connected intelligent hybrid system are proposed using MATLAB/Simulink.

Voltage Quality Improvement Using Solar Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Denisa Galzina

2015-06-01

This paper briefly shows the methods of power quality improvement, and then the results of on-site power quality measurements in the grid before and after the connection of the solar photovoltaic system.

Analysis of grid connected solar PV system in the Southeastern Part of Bangladesh

International Nuclear Information System (INIS)

Ariful Islam; Fatema Akther Shima; Akhera Khanam

2013-01-01

Bangladesh is a potential site of implementing renewable energy system to reduce the severe power crisis throughout the year. According to this, Chittagong is the southeastern part of Bangladesh is also a potential site for implementing renewable energy system such as grid-connected photovoltaic (PV) system. Financial viability and green-house gas emission reduction of solar PV as an electricity generation source are assessed for 500 kW grid connected solar PV system at University of Chittagong, Chittagong. Homer simulation soft-ware and monthly average solar radiation data from NASA is used for this task. In the proposed system monthly electricity generation varies between 82.65 MW h and 60.3 MW h throughout the year with a mean value of 68.25 MW h depending on the monthly highest and lowest solar radiation data. It is found that per unit electricity production cost is US$ 0.20 based on project lifetime 25 years. The IRR, equity payback and benefit-cost ratio shows favorable condition for development of the proposed solar PV system in this site. A minimum 664 tones of green-house gas emissions can be reduced annually utilizing the proposed system. (authors)

A GRID-CONNECTED HYBRID WIND-SOLAR POWER SYSTEM

Directory of Open Access Journals (Sweden)

MAAMAR TALEB

2017-06-01

Full Text Available A hybrid renewable energy system consisting of a photovoltaic generator and a wind driven DC machine is interconnected with the power utilities grid. The interconnection is done through the use of two separate single phase full wave controlled bridge converters. The bridge converters are operated in the “inverter mode of operation”. That is to guaranty the extraction of the real powers from the wind driven generator as well as from the photovoltaic generator and inject them into the power utilities grid. At any pretended surrounding weather conditions, maximum extraction of powers from both renewable energy sources is targeted. This is done through the realization of self-adjusted firing angle controllers responsible of triggering the semiconductor elements of the controlled converters. An active power filter is shunted with the proposed setup to guaranty the sinusoid quality of the power utilities line current. The overall performance of the proposed system has been simulated in MATLAB/SIMULINK environment. Quite satisfactory and encouraging results have been obtained.

Adaptive control paradigm for photovoltaic and solid oxide fuel cell in a grid-integrated hybrid renewable energy system.

Science.gov (United States)

Mumtaz, Sidra; Khan, Laiq

2017-01-01

The hybrid power system (HPS) is an emerging power generation scheme due to the plentiful availability of renewable energy sources. Renewable energy sources are characterized as highly intermittent in nature due to meteorological conditions, while the domestic load also behaves in a quite uncertain manner. In this scenario, to maintain the balance between generation and load, the development of an intelligent and adaptive control algorithm has preoccupied power engineers and researchers. This paper proposes a Hermite wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control of photovoltaic (PV) systems to extract maximum power and a Hermite wavelet incorporated NeuroFuzzy indirect adaptive control of Solid Oxide Fuel Cells (SOFC) to obtain a swift response in a grid-connected hybrid power system. A comprehensive simulation testbed for a grid-connected hybrid power system (wind turbine, PV cells, SOFC, electrolyzer, battery storage system, supercapacitor (SC), micro-turbine (MT) and domestic load) is developed in Matlab/Simulink. The robustness and superiority of the proposed indirect adaptive control paradigm are evaluated through simulation results in a grid-connected hybrid power system testbed by comparison with a conventional PI (proportional and integral) control system. The simulation results verify the effectiveness of the proposed control paradigm.

Adaptive control paradigm for photovoltaic and solid oxide fuel cell in a grid-integrated hybrid renewable energy system

Science.gov (United States)

Khan, Laiq

2017-01-01

The hybrid power system (HPS) is an emerging power generation scheme due to the plentiful availability of renewable energy sources. Renewable energy sources are characterized as highly intermittent in nature due to meteorological conditions, while the domestic load also behaves in a quite uncertain manner. In this scenario, to maintain the balance between generation and load, the development of an intelligent and adaptive control algorithm has preoccupied power engineers and researchers. This paper proposes a Hermite wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control of photovoltaic (PV) systems to extract maximum power and a Hermite wavelet incorporated NeuroFuzzy indirect adaptive control of Solid Oxide Fuel Cells (SOFC) to obtain a swift response in a grid-connected hybrid power system. A comprehensive simulation testbed for a grid-connected hybrid power system (wind turbine, PV cells, SOFC, electrolyzer, battery storage system, supercapacitor (SC), micro-turbine (MT) and domestic load) is developed in Matlab/Simulink. The robustness and superiority of the proposed indirect adaptive control paradigm are evaluated through simulation results in a grid-connected hybrid power system testbed by comparison with a conventional PI (proportional and integral) control system. The simulation results verify the effectiveness of the proposed control paradigm. PMID:28329015

Two-loop controller for maximizing performance of a grid-connected photovoltaic - fuel cell hybrid power plant

Science.gov (United States)

Ro, Kyoungsoo

The study started with the requirement that a photovoltaic (PV) power source should be integrated with other supplementary power sources whether it operates in a stand-alone or grid-connected mode. First, fuel cells for a backup of varying PV power were compared in detail with batteries and were found to have more operational benefits. Next, maximizing performance of a grid-connected PV-fuel cell hybrid system by use of a two-loop controller was discussed. One loop is a neural network controller for maximum power point tracking, which extracts maximum available solar power from PV arrays under varying conditions of insolation, temperature, and system load. A real/reactive power controller (RRPC) is the other loop. The RRPC meets the system's requirement for real and reactive powers by controlling incoming fuel to fuel cell stacks as well as switching control signals to a power conditioning subsystem. The RRPC is able to achieve more versatile control of real/reactive powers than the conventional power sources since the hybrid power plant does not contain any rotating mass. Results of time-domain simulations prove not only effectiveness of the proposed computer models of the two-loop controller, but also their applicability for use in transient stability analysis of the hybrid power plant. Finally, environmental evaluation of the proposed hybrid plant was made in terms of plant's land requirement and lifetime COsb2 emissions, and then compared with that of the conventional fossil-fuel power generating forms.

Proposing Wavelet-Based Low-Pass Filter and Input Filter to Improve Transient Response of Grid-Connected Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Bijan Rahmani

2016-08-01

Full Text Available Available photovoltaic (PV systems show a prolonged transient response, when integrated into the power grid via active filters. On one hand, the conventional low-pass filter, employed within the integrated PV system, works with a large delay, particularly in the presence of system’s low-order harmonics. On the other hand, the switching of the DC (direct current–DC converters within PV units also prolongs the transient response of an integrated system, injecting harmonics and distortion through the PV-end current. This paper initially develops a wavelet-based low-pass filter to improve the transient response of the interconnected PV systems to grid lines. Further, a damped input filter is proposed within the PV system to address the raised converter’s switching issue. Finally, Matlab/Simulink simulations validate the effectiveness of the proposed wavelet-based low-pass filter and damped input filter within an integrated PV system.

Photovoltaic systems engineering

CERN Document Server

Messenger, Roger A

2010-01-01

BackgroundPopulation and Energy DemandEnergy UnitsCurrent World Energy Use PatternsExponential GrowthHubbert's Gaussian ModelNet Energy, Btu Economics, and the Test for SustainabilityDirect Conversion of Sunlight to Electricity with PhotovoltaicsThe SunThe Solar SpectrumThe Effect of Atmosphere on SunlightSunlight SpecificsCapturing SunlightIntroduction to PV SystemsThe PV CellThe PV ModuleThe PV ArrayEnergy StoragePV System LoadsPV System AvailabilityAssociated System Electronic ComponentsGeneratorsBalance of System (BOS) ComponentsGrid-Connected Utility-Interactive PV SystemsApplicable Codes and StandardsDesign Considerations for Straight Grid-Connected PV SystemsDesign of a System Based on Desired Annual System PerformanceDesign of a System Based on Available Roof SpaceDesign of a Microinverter-Based SystemDesign of a Nominal 21 kW System that Feeds a Three-Phase Distribution PanelDesign of a Nominal 250 kW SystemSystem Performance MonitoringMechanical ConsiderationsImportant Properties of MaterialsEstabli...

Optimizing Grid Patterns on Photovoltaic Cells

Science.gov (United States)

Burger, D. R.

1984-01-01

CELCAL computer program helps in optimizing grid patterns for different photovoltaic cell geometries and metalization processes. Five different powerloss phenomena associated with front-surface metal grid pattern on photovoltaic cells.

Photovoltaic system connected to electric grid in Brazil; Sistemas fotovoltaicos conectados a rede eletrica no Brasil

Energy Technology Data Exchange (ETDEWEB)

Varella, Fabiana Karla de Oliveira Martins [Universidade Federal Rural do Semi-Arido (UFERSA), Mossoro, RN (Brazil)], email: fkv@ufersa.edu.br; Gomes, Rodolfo Dourado Maia; Jannuzzi, Gilberto De Martino [International Energy Initiative (IEI), Campinas, SP (Brazil)], email: rodolfo@iei-la.org

2010-07-01

Brazil has in the next decades the big challenge of seeking for solutions to meet its growing energy service needs and, at the same time, satisfy criteria of economics, security of supply, public health, secure universal energy access and environmental sustainability. The growing environmental pressures over the hydropower potential exploitation at the Amazon region and the energy sources even more distant from the customer load center are some of the aspects which are posed in order to seek for solutions. Several countries are betting on grid-connected PV systems. In Brazil, the initiatives to promote the use of PV energy are still a few. Even though the country is endowed with a great solar energy potential, the initiatives to create and consolidate a market for the use of such technology and to develop the national industry for equipment and services are still incipient. The lack of legislation and regulation is one of the barriers pointed out. Thus, the objective of this report is to assess the reasons why the country does not have a specific legislation to promote the use of grid-connected PV systems. For such, grid-connected PV systems installed in Brazil and the existent incentives are identified. The methodology used was based on literature review and conduction of specific questionnaires. The latter was sent to the Ministry of Mines and Energy, researchers and one power distribution company. (author)

Performance analysis of a 11.2 kWp roof top grid-connected PV system in Eastern India

Directory of Open Access Journals (Sweden)

Renu Sharma

2017-11-01

Full Text Available Barren land and roof tops of buildings are being increasingly used worldwide to install solar panels for generating electricity. One such step has been taken by Siksha ‘O’Anusandhan University, Bhubaneswar (Latitude 20.24° N and Longitude 80.85° E by installing a 11.2 kWp grid connected solar power system during February, 2014. This PV system is tilted at an angle of 21° on the top floor of a 25 metre height building. This system was installed This paper presents the results of this grid connected photovoltaic system which was monitored between September 2014 to August 2015. The entire electricity generated by the system was fed into the state grid. The different parameters of the system studied include PV module efficiency, array yield, final yield, inverter efficiency and performance ratio of the system. The total energy generated during this period was found to be 14.960 MWh and the PV module efficiency, inverter efficiency and performance ratio were found to be 13.42%, 89.83% and 0.78 respectively.

Factors Associated with Photovoltaic System Costs (Topical Issues Brief)

Energy Technology Data Exchange (ETDEWEB)

Mortensen, J.

2001-06-12

A variety of factors can affect the cost of photovoltaic systems. This report analyses the relationship among such factors by using information entered into a voluntary registry of PV systems and performing regression analyses. The results showed statistically significant relationships between photovoltaic system cost and (a) grid connection, (b) installation year, (c) areas where the utility had entered into volume purchasing agreements.

Power control based on particle swarm optimization of grid-connected inverter for hybrid renewable energy system

International Nuclear Information System (INIS)

García-Triviño, Pablo; Gil-Mena, Antonio José; Llorens-Iborra, Francisco; García-Vázquez, Carlos Andrés; Fernández-Ramírez, Luis M.; Jurado, Francisco

2015-01-01

Highlights: • Three PSO-based PI controllers for a grid-connected inverter were presented. • Two online PSO-based PI controllers were compared with an offline PSO-tuned PI. • The HRES and the inverter were evaluated under power changes and grid voltage sags. • Online ITAE-based PSO reduced ITAE (current THD) by 15.24% (5.32%) versus offline one. - Abstract: This paper is focused on the study of particle swarm optimization (PSO)-based PI controllers for the power control of a grid-connected inverter supplied from a hybrid renewable energy system. It is composed of two renewable energy sources (wind turbine and photovoltaic – PV – solar panels) and two energy storage systems (battery and hydrogen system, integrated by fuel cell and electrolyzer). Three PSO-based PI controllers are implemented: (1) conventional PI controller with offline tuning by PSO algorithm based on the integral time absolute error (ITAE) index; (2) PI controllers with online self-tuning by PSO algorithm based on the error; and (3) PI controllers with online self-tuning by PSO algorithm based on the ITAE index. To evaluate and compare the three controllers, the hybrid renewable energy system and the grid-connected inverter are simulated under changes in the active and reactive power values, as well as under a grid voltage sag. The results show that the online PSO-based PI controllers that optimize the ITAE index achieves the best response

Design, testing, and economics of a 430 W sub p photovoltaic concentrator array for non grid-connected applications

Science.gov (United States)

Maish, A. B.; Rios, M., Jr.; Togami, H.

A stand-alone 430 W/sub p/ photovoltaic (PV) concentrating system for low power, non grid-connected applications has been designed, fabricated, and tested at Sandia National Laboratories. The array consists of four passively cooled Fresnel lens concentrating modules on a newly developed polar axis tracking structure. Two axis tracking is provided using a self powered clock drive unit mounted on a single post foundation. Test results of tracking accuracy, array output power, parasitic power, performance in winds and array reliability are discussed. using a range of estimated production costs for small production volumes, the life-cycle energy costs have been calculated and compared to the equivalent energy costs of a 3 kW diesel electric generator set and of an equivalent flat panel PV system.

Analysis of Photovoltaic Self-Consumption Systems

Directory of Open Access Journals (Sweden)

Carlos J. Sarasa-Maestro

2016-08-01

Full Text Available Components and installation prices could make the self-consumption of solar photovoltaic (PV systems competitive. In this paper, we explore different self-consumption options, off-grid PV systems (with back-up generator and/or batteries, and grid-connected PV systems under net-metering policies. The calculation of the net present cost (NPC reveals that the grid-connected PV-only case (for the net-metering scheme is the most attractive from the technical and financial points of view, with a levelised cost of energy less than 0.1 €/kWh. Off-grid PV + Diesel + Batteries has a higher cost, around two or three times the grid-connected PV-only under net metering. Additionally, the off-grid PV + Diesel is less attractive from a financial point of view, which has a cost of around 10 times the PV-only under net metering. In addition, the values of life cycle CO2 emissions in each of the cases studied have been compared, and we have concluded that although the off-grid PV + Diesel + Batteries system presents lower CO2 emissions than the PV-only system, the existence of batteries does not allow one to affirm that the PV + Diesel + Batteries system is the best from an environmental point of view.

An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions

Science.gov (United States)

Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M.

2017-01-01

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method. PMID:28192436

An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions.

Science.gov (United States)

Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M

2017-01-01

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method.

A proposal for off-grid photovoltaic systems with non-controllable loads using fuzzy logic

International Nuclear Information System (INIS)

Yahyaoui, Imene; Sallem, Souhir; Kamoun, M.B.A.; Tadeo, Fernando

2014-01-01

Highlights: • An energy management system is proposed for off-grid PV systems, based on fuzzy logic. • The proposal guarantees the energy balance and battery protection. • The approach is demonstrated using data measured at the target location. - Abstract: A fuzzy-logic based methodology is proposed and evaluated for energy management in off-grid installations with photovoltaic panels as the source of energy and a limited storage capacity in batteries. The decision on the connection or disconnection of components is based on fuzzy rules on the basis of the Photovoltaic Panel Generation measurement, the measured power required by the load, and the estimation of the stored energy in the batteries (this last is obtained from the estimation of the Depth-of-Discharge). The algorithm aims to ensure the system’s autonomy by controlling the switches linking the system components with respect to a multi-objective management criterion developed from the requirements (supply of the load, protection of the battery, etc.). Detailed tests of the proposed system are carried out using data (irradiation, temperature, power consumption, etc.) measured in a household at the target area at several days of the year. The results demonstrate that the proposed approach achieves the objectives of system autonomy, battery protection and power supply stability. Compared with a basic algorithm, the proposed algorithm is not sensitive to sudden changes in atmospheric parameters and avoids overcharging the battery

New current control based MPPT technique for single stage grid connected PV systems

International Nuclear Information System (INIS)

Jain, Sachin; Agarwal, Vivek

2007-01-01

This paper presents a new maximum power point tracking algorithm based on current control for a single stage grid connected photovoltaic system. The main advantage of this algorithm comes from its ability to predict the approximate amplitude of the reference current waveform or power that can be derived from the PV array with the help of an intermediate variable β. A variable step size for the change in reference amplitude during initial tracking helps in fast tracking. It is observed that if the reference current amplitude is greater than the array capacity, the system gets unstable (i.e. moves into the positive slope region of the p-v characteristics of the array). The proposed algorithm prevents the PV system from entering the positive slope region of the p-v characteristics. It is also capable of restoring stability if the system goes unstable due to a sudden environmental change. The proposed algorithm has been tested on a new single stage grid connected PV configuration recently developed by the authors to feed sinusoidal current into the grid. The system is operated in a continuous conduction mode to realize advantages such as low device current stress, high efficiency and low EMI. A fast MPPT tracker with single stage inverter topology operating in CCM makes the overall system highly efficient. Specific cases of the system, operating in just discontinuous current mode and discontinuous current mode and their relative merits and demerits are also discussed

Grid Connected Solar PV System with SEPIC Converter Compared with Parallel Boost Converter Based MPPT

Directory of Open Access Journals (Sweden)

T. Ajith Bosco Raj

2014-01-01

Full Text Available The main objective of this work is to study the behaviour of the solar PV systems and model the efficient Grid-connected solar power system. The DC-DC MPPT circuit using chaotic pulse width modulation has been designed to track maximum power from solar PV module. The conversion efficiency of the proposed MPPT system is increased when CPWM is used as a control scheme. This paper also proposes a simplified multilevel (seven level inverter for a grid-connected photovoltaic system. The primary goal of these systems is to increase the energy injected to the grid by keeping track of the maximum power point of the panel, by reducing the switching frequency, and by providing high reliability. The maximum power has been tracked experimentally. It is compared with parallel boost converter. Also this model is based on mathematical equations and is described through an equivalent circuit including a PV source with MPPT, a diode, a series resistor, a shunt resistor, and dual boost converter with active snubber circuit. This model can extract PV power and boost by using dual boost converter with active snubber. By using this method the overall system efficiency is improved thereby reducing the switching losses and cost.

A Novel Method for Fast Configuration of Energy Storage Capacity in Stand-Alone and Grid-Connected Wind Energy Systems

Directory of Open Access Journals (Sweden)

Haixiang Zang

2016-12-01

Full Text Available In this paper, a novel method is proposed and applied to quickly calculate the capacity of energy storage for stand-alone and grid-connected wind energy systems, according to the discrete Fourier transform theory. Based on practical wind resource data and power data, which are derived from the American Wind Energy Technology Center and HOMER software separately, the energy storage capacity of a stand-alone wind energy system is investigated and calculated. Moreover, by applying the practical wind power data from a wind farm in Fujian Province, the energy storage capacity for a grid-connected wind system is discussed in this paper. This method can also be applied to determine the storage capacity of a stand-alone solar energy system with practical photovoltaic power data.

Optimum Design Of On Grid Pv System Using Tracking System

Directory of Open Access Journals (Sweden)

Saeed Mansour

2015-05-01

Full Text Available Abstract The fossil fuel is a main issue in the world due to the increase of fossil fuel cost and the depletion of the fossil fuel with continuous increasing demand on electricity. With continuous decrease of PV panels cost it is interesting to consider generation of electricity from PV system. To provide electric energy to a load in a remote area where electric grid utility is not available or connection with grid utility is available there are two approaches of photovoltaic system PV without tracking system Fixed System and PV with tracking systems. The result shows that the energy production by using PV with tracking system generates more energy in comparison with fixed panels system. However the cost per produced KWH is less in case of using fixed panels. This is the backbone in choice between two approaches of photovoltaic system. In this work a system design and cost analysis for two approaches of photovoltaic system are considered.

Benchmarking of Constant Power Generation Strategies for Single-Phase Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2018-01-01

strategies based on: 1) a power control method (P-CPG), 2) a current limit method (I-CPG) and 3) the Perturb and Observe algorithm (P&O-CPG). However, the operational mode changes (e.g., from the maximum power point tracking to a CPG operation) will affect the entire system performance. Thus, a benchmarking...... of the presented CPG strategies is also conducted on a 3-kW single-phase grid-connected PV system. Comparisons reveal that either the P-CPG or I-CPG strategies can achieve fast dynamics and satisfactory steady-state performance. In contrast, the P&O-CPG algorithm is the most suitable solution in terms of high...

Performance simulation of a grid connected photovoltaic power system using TRNSYS 17

Science.gov (United States)

Raja Sekhar, Y.; Ganesh, D.; Kumar, A. Suresh; Abraham, Raju; Padmanathan, P.

2017-11-01

Energy plays an important role in a country’s economic growth in the current energy scenario, the major problem is depletion of energy sources (non-renewable) are more than being formed. One of the prominent solutions is minimizing the use of fossil fuels by utilization of renewable energy resources. A photovoltaic system is an efficient option in terms of utilizing the solar energy resource. The electricity output produced by the photovoltaic systems depends upon the incident solar radiation. This paper examines the performance simulation of 200KW photovoltaic power system at VIT University, Vellore. The main objective of this paper is to correlate the results between the predicted simulation data and the experimental data. The simulation tool used here is TRNSYS. Using TRNSYS modelling prediction of electricity produced throughout the year can be calculated with the help of TRNSYS weather station. The deviation of the simulated results with the experimented results varies due to the choice of weather station. Results from the field test and simulation results are to be correlated to attain the maximum performance of the system.

Distributed photovoltaic grid transformers

CERN Document Server

Shertukde, Hemchandra Madhusudan

2014-01-01

The demand for alternative energy sources fuels the need for electric power and controls engineers to possess a practical understanding of transformers suitable for solar energy. Meeting that need, Distributed Photovoltaic Grid Transformers begins by explaining the basic theory behind transformers in the solar power arena, and then progresses to describe the development, manufacture, and sale of distributed photovoltaic (PV) grid transformers, which help boost the electric DC voltage (generally at 30 volts) harnessed by a PV panel to a higher level (generally at 115 volts or higher) once it is

Optimal Design of MPPT Controllers for Grid Connected Photovoltaic Array System

Science.gov (United States)

Ebrahim, M. A.; AbdelHadi, H. A.; Mahmoud, H. M.; Saied, E. M.; Salama, M. M.

2016-10-01

Integrating photovoltaic (PV) plants into electric power system exhibits challenges to power system dynamic performance. These challenges stem primarily from the natural characteristics of PV plants, which differ in some respects from the conventional plants. The most significant challenge is how to extract and regulate the maximum power from the sun. This paper presents the optimal design for the most commonly used Maximum Power Point Tracking (MPPT) techniques based on Proportional Integral tuned by Particle Swarm Optimization (PI-PSO). These suggested techniques are, (1) the incremental conductance, (2) perturb and observe, (3) fractional short circuit current and (4) fractional open circuit voltage techniques. This research work provides a comprehensive comparative study with the energy availability ratio from photovoltaic panels. The simulation results proved that the proposed controllers have an impressive tracking response. The system dynamic performance improved greatly using the proposed controllers.

Design Optimization of Transformerless Grid-Connected PV Inverters Including Reliability

OpenAIRE

Koutroulis, Eftichios; Blaabjerg, Frede

2013-01-01

This paper presents a new methodology for optimal design of transformerless photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal switching frequency as well as the optimal values and types of the PV inverter components is calculated such that the PV inverter LCOE generated during the PV system lifetime period is minimized. The LCOE is also calculated considering the failure rates of the components, which affect the reliability performance...

Forecasting the daily power output of a grid-connected photovoltaic system based on multivariate adaptive regression splines

International Nuclear Information System (INIS)

Li, Yanting; He, Yong; Su, Yan; Shu, Lianjie

2016-01-01

Highlights: • Suggests a nonparametric model based on MARS for output power prediction. • Compare the MARS model with a wide variety of prediction models. • Show that the MARS model is able to provide an overall good performance in both the training and testing stages. - Abstract: Both linear and nonlinear models have been proposed for forecasting the power output of photovoltaic systems. Linear models are simple to implement but less flexible. Due to the stochastic nature of the power output of PV systems, nonlinear models tend to provide better forecast than linear models. Motivated by this, this paper suggests a fairly simple nonlinear regression model known as multivariate adaptive regression splines (MARS), as an alternative to forecasting of solar power output. The MARS model is a data-driven modeling approach without any assumption about the relationship between the power output and predictors. It maintains simplicity of the classical multiple linear regression (MLR) model while possessing the capability of handling nonlinearity. It is simpler in format than other nonlinear models such as ANN, k-nearest neighbors (KNN), classification and regression tree (CART), and support vector machine (SVM). The MARS model was applied on the daily output of a grid-connected 2.1 kW PV system to provide the 1-day-ahead mean daily forecast of the power output. The comparisons with a wide variety of forecast models show that the MARS model is able to provide reliable forecast performance.

Presentations given at the Enerplan Conference: facilitating photovoltaic energy integration in the grid

International Nuclear Information System (INIS)

Mueth, Thierry; Thomas, Christophe; Loyen, Richard; Masson, Gaetan; Najdawi, Celine; Dubus, Jean-Michel; Carre, Olivier; Resseguier, Stephane de; Alazard, Raymond; Prest, Ignace de; Humez, Herve; Kaiser, Martin; Cassagne, Valerick; Dauphin, Francois; Merley, Jacques; Laffaille, Didier; Gossement, Arnaud; Belon, Daniel; Blanquet, Francois; Bonnet, Jean-Philippe; Sanchez, Louis; Vienot, Raphaelle; Lambert, Karine; Berly, Frederic

2013-07-01

Large-scale integration of photovoltaic energy in power grids are present day topics of strategical stakes for the development of the photovoltaic industry and for the success of the energy transition. This conference provided some answers to three main subjects which were the main themes of the 3 round-tables: 1 - Identifying the context elements leading to a large integration of solar energy in Europe and in France; 2 - Identifying the technical solutions facilitating the technical integration of photovoltaic energy in power grids; 3 - Analysing the expected regional schemes for connecting renewable energies to the network, in order to shift from an administrative planning to a dynamical and practical approach profitable to the photovoltaic industry. This document brings together the available presentations (slides) given at the colloquium

An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions

DEFF Research Database (Denmark)

Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz

2017-01-01

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions....... It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method...... is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed...

Dynamic of small photovoltaic systems

Science.gov (United States)

Mehrmann, A.; Kleinkauf, W.; Pigorsch, W.; Steeb, H.

The results of 1.5 yr of field-testing of two photovoltaic (PV) power plants, one equipped with an electrolyzer and H2 storage, are reported. Both systems were interconnected with the grid and featured the PV module, a power conditioning unit, ac and dc load connections, and control units. The rated power of both units was 100 Wp. The system with electrolysis was governed by control laws which maximized the electrolyzer current. The tests underscored the preference for a power conditioning unit, rather than direct output to load connections. A 1 kWp system was developed in a follow-up program and will be tested in concert with electrolysis and interconnection with several grid customers. The program is geared to eventual development of larger units for utility-size applications.

Control Strategies for Trap Filter Interfaced Three-Phase Grid Connected Converters

DEFF Research Database (Denmark)

Min, Huang

In order to utilize renewable energy systems power electronics are needed to convert the energy to grid. The AC-DC and DC-AC power conversion are dominant in wind power system and photovoltaic system. However, the use of PWM scheme introduces undesirable harmonics. In order to enhance the grid...... damping in order to stabilize the whole system with resonance issue. LC trap filter application for current source converters to reduce the size of the filter and get a higher power factor....... integration of the renewable energy systems, the filter plays an important role. Even though this topic has already been widely studied, there are many optimizations and problems should be solved. How to design a filter for grid-connected converters in distributed generation system to get a lower loss...

Energy Storage Management in Grid Connected Solar Photovoltaic System

OpenAIRE

Vidhya M.E

2015-01-01

The penetration of renewable sources in the power system network in the power system has been increasing in the recent years. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage device into the power system network. This paper discusses the modeling of photo voltaic and status of the storage device such as lead acid battery for better energy management in the system. The energy management for the grid conne...

Development of Flexible Active Power Control Strategies for Grid-Connected Photovoltaic Inverters by Modifying MPPT Algorithms

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2017-01-01

As the penetration level of grid-connected PV systems increases, more advanced control functionality is demanded. In order to ensure smooth and friendly grid integration as well as enable more PV installations, the power generated by PV systems needs to be flexible and capable of: 1) limiting...... strategies for grid-connected PV inverters by modifying maximum power point tracking algorithms, where the PV power is regulated by changing the operating point of the PV system. In this way, no extra equipment is needed, being a cost-effective solution. Experiments on a 3-kW grid-connected PV system have...... the maximum feed-in power, 2) ensuring a smooth change rate, and 3) providing a power reserve. Besides, such flexible power control functionalities have to be achieved in a cost-effective way in order to ensure the competitiveness of solar energy. Therefore, this paper explores flexible active power control...

Grid-connected inverter for wind power generation system

Institute of Scientific and Technical Information of China (English)

YANG Yong; RUAN Yi; SHEN Huan-qing; TANG Yan-yan; YANG Ying

2009-01-01

In wind power generation system the grid-connected inverter is an important section for energy conversion and transmission, of which the performance has a direct influence on the entire wind power generation system. The mathematical model of the grid-connected inverter is deduced firstly. Then, the space vector pulse width modulation (SVPWM) is analyzed. The power factor can be controlled close to unity, leading or lagging, which is realized based on PI-type current controller and grid voltage vector-oriented control. The control strategy is verified by the simulation and experimental results with a good sinusoidal current, a small harmonic component and a fast dynamic response.

Online Grid Measurement and ENS Detection for PV Inverter Running on Highly Inductive Grid

DEFF Research Database (Denmark)

Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

2004-01-01

Photovoltaic (PV) and other sources of renewable energy are being used increasingly in grid-connected systems, for which stronger power quality requirements are being issued. Continuous grid monitoring should be considered so as to provide safe connections and disconnections from the grid...

光伏并网式家用空调系统性能的实验研究%Experimental Investigation on the Performance of Household Air Conditioning System with Grid-connected Photovoltaic Generation

Institute of Scientific and Technical Information of China (English)

金听祥; 徐笑锋

2015-01-01

With the base of traditional air conditioning system, the grid-connected photovoltaic household air conditioning sys-tem based on the solar photovoltaic power generation technology is designed in this paper. The power with the solar photovoltaic power generation technology is transformed into the household power of 220 V and 50 Hz by inverter. The household air condi-tioning system is then driven by the transformed power and national grid. The performance of the photovoltaic grid-connected household air conditioning system was tested by Enthalpy Difference Lab under the different power ( 100 W, 135 W and 185 W) of solar panels. The experimental results show that under normal cooling conditions, the average power consumption of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 52 W, 78 W and 104 W lower than that of the traditional air conditioning system respectively. Similarly, energy efficiency ratios of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 4. 2%, 5. 5% and 10. 2% lower than that of the tra-ditional air conditioning system respectively. Under heating mode, the average power consumption of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 68 W, 84 W and 116 W lower than that of the tradi-tional air conditioning system, and the coefficients of performances are 6. 4%, 8% and 11% lower than that of the traditional air conditioning system. It can be concluded that the photovoltaic grid-connected household air conditioning system is feasible.%针对目前的家用空调系统,本文设计了一种以太阳能光伏发电技术为基础,与国家电网并网,共同驱动空调工作的系统,称为光伏并网式家用空调系统。利用光伏发电技术,通过逆变器将太阳能提供的电力转变为220 V、50 Hz�

Three-Phase Grid-Connected of Photovoltaic Generator Using Nonlinear Control

DEFF Research Database (Denmark)

Yahya, A.; El Fadil, H.; Guerrero, Josep M.

2014-01-01

This paper proposes a nonlinear control methodology for three phase grid connected of PV generator. It consists of a PV arrays; a voltage source inverter, a grid filter and an electric grid. The controller objectives are threefold: i) ensuring the Maximum power point tracking (MPPT) in the side...... stability analysis and simulation results that the proposed controller meets all the objectives....

Grid-connected solar electricity going mainstream

International Nuclear Information System (INIS)

MacLellan, I.

2004-01-01

In 20 days, the sun provides the equivalent amount of energy found in all known fossil fuel reserves. This paper provides an outline of solar energy industry activities from the perspective of Arise Technologies, a Canadian-based solar energy company. An overview of the company's vision and marketing strategy was presented, including annual sales. Details of the company's commercial projects were reviewed, with specific reference to the first Canadian grid-connected solar electric subdivision. An introduction to photovoltaic electricity (PV) as an environmentally positive energy source was presented. Statistics included information on the current solar market worldwide as well as government and industry investment. Portable solar energy applications were provided, as well as grid-tied products in relation to private dwelling and commercial, industrial and institutional buildings. Details of an Arise solar home were presented. An outline of the Technology Early Action Measures (TEAM) was presented, with reference to the federal government's Climate Change Action Plan. The benefits of solar economics were given. PV factory production was overviewed, with a presentation of the experience curve and the number of grid-connected solar electric homes globally. Top global PV manufacturers were listed as well as a chart of world energy transitions underlining the emergence of renewable energy programs and systems. A summary of solar energy in Japan was provided, along with details of mid and long term solar energy planning, as well as other projects around the world. Canadian investment in PV was compared with other countries and details of past government spending on other energy sources were also presented. It was concluded that Canada was far behind other G-8 countries with reference to grid-connected PV, but that off-grid PV was a real business in Canada. It was also concluded that Japan would represent the first real mainstream grid-connected market, followed by Europe

Grid-connected solar electricity going mainstream

Energy Technology Data Exchange (ETDEWEB)

MacLellan, I. [Arise Technologies Corp., Kitchener, ON (Canada)

2004-06-01

In 20 days, the sun provides the equivalent amount of energy found in all known fossil fuel reserves. This paper provides an outline of solar energy industry activities from the perspective of Arise Technologies, a Canadian-based solar energy company. An overview of the company's vision and marketing strategy was presented, including annual sales. Details of the company's commercial projects were reviewed, with specific reference to the first Canadian grid-connected solar electric subdivision. An introduction to photovoltaic electricity (PV) as an environmentally positive energy source was presented. Statistics included information on the current solar market worldwide as well as government and industry investment. Portable solar energy applications were provided, as well as grid-tied products in relation to private dwelling and commercial, industrial and institutional buildings. Details of an Arise solar home were presented. An outline of the Technology Early Action Measures (TEAM) was presented, with reference to the federal government's Climate Change Action Plan. The benefits of solar economics were given. PV factory production was overviewed, with a presentation of the experience curve and the number of grid-connected solar electric homes globally. Top global PV manufacturers were listed as well as a chart of world energy transitions underlining the emergence of renewable energy programs and systems. A summary of solar energy in Japan was provided, along with details of mid and long term solar energy planning, as well as other projects around the world. Canadian investment in PV was compared with other countries and details of past government spending on other energy sources were also presented. It was concluded that Canada was far behind other G-8 countries with reference to grid-connected PV, but that off-grid PV was a real business in Canada. It was also concluded that Japan would represent the first real mainstream grid-connected market

Optimization of Renewable Energy Hybrid System for Grid Connected Application

Directory of Open Access Journals (Sweden)

Mustaqimah Mustaqimah

2012-10-01

Full Text Available ABSTRACT. Hybrid energy systems are pollution free, takes low cost and less gestation period, user and social friendly. Such systems are important sources of energy for shops, schools, and clinics in village communities especially in remote areas. Hybrid systems can provide electricity at a comparatively economic price in many remote areas. This paper presents a method to jointly determine the sizing and operation control of hybrid energy systems. The model, PV wind hydro and biomass hybrid system connects to grid. The system configuration of the hybrid is derived based on a theoretical domestic load at a typical location and local solar radiation, wind and water flow rate data and biomass availability. The hybrid energy system is proposed for 10 of teacher’s houses of Industrial Training Institute, Mersing. It is predicted 10 kW load consumption per house. The hybrid energy system consists of wind, solar, biomass, hydro, and grid power. Approximately energy consumption is 860 kWh/day with a 105 kW peak demand load. The proposed hybrid renewable consists of solar photovoltaic (PV panels, wind turbine, hydro turbine and biomass. Battery and inverter are included as part of back-up and storage system. It provides the economic sensitivity of hybridization and the economic and environmental benefits of using a blend of technologies. It also presents the trade off that is involved in optimizing a hybrid energy system to harness and utilize the available renewable energy resources efficiently.

Aspects of a generic photovoltaic model examined under the German grid code for medium voltage

Energy Technology Data Exchange (ETDEWEB)

Theologitis, Ioannis-Thomas; Troester, Eckehard; Ackermann, Thomas [Energynautics GmbH, Langen (Germany)

2011-07-01

The increasing peneration of photovoltaic power systems into the power grid has attached attention to the issue of ensuring the smooth absorbance of the solar energy, while securing the normal and steady operation of the grid as well. Nowadays, the PV systems must meet a number of technical requirements to address this issue. This paper investigates a generic grid-connected photovoltaic model that was developed by DIgSILENT and is part of the library in the new version of PowerFactory v.14.1 software that is used in this study. The model has a nominal rated peak power of 0.5 MVA and a designed power factor cos{phi}0.95. The study focuses on the description of the model, its control system and its ability to reflect important requirements that a grid-connected PV system should have by January 2011 according to the German grid code for medium voltage. The model undergoes various simulations. Static voltage support, active power control and dynamic voltage support - Fault Ride Through (FRT) is examined. The results show that the generic model is capable for active power reduction under over-frequency occasions and FRT behavior in cases of voltage dips. The reactive power control that is added in the model improves the control system and makes the model capable for static voltage support in sudden active power injection changes at the point of common coupling. Beside the simplifications and shortcomings of this generic model, basic requirements of the modern PV systems can be addressed. Further improvements could make it more complete and applicable for more detailed studies. (orig.)

UPVG efforts to commercialize photovoltaics

International Nuclear Information System (INIS)

Serfass, J.A.; Wills, B.N.

1995-01-01

The Utility PhotoVoltaic Group (UPVG) was formed in October of 1992 with a mission to accelerate the use of cost-effective small-scale and emerging grid-connected applications of photovoltaics for the benefit of electric utilities and their customers. The UPVG is now implementing a program to install up to 50 megawatts of photovoltaics in small-scale and grid-connected applications. This program, called TEAM-UP, is a partnership of the US electric utility industry and the US Department of Energy to help develop utility PV markets. TEAM-UP is a utility-directed program to significantly increase utility PV experience by promoting installations of utility PV systems. Two primary program areas are proposed for TEAM-UP: (1) Small-Scale Applications (SSA)--an initiative to aggregate utility purchases of small-scale, grid-independent applications; and (2) Grid-Connected Applications (GCA)--an initiative to identify and competitively award cost-sharing contracts for grid-connected PV systems with high market growth potential, or collective purchase programs involving multiple buyers. This paper describes these programs and outlines the schedule, the procurement status, and the results of the TEAM-UP process

Adaptive super-twisting sliding mode control for a three-phase single-stage grid-connected differential boost inverter based photovoltaic system.

Science.gov (United States)

Pati, Akshaya K; Sahoo, N C

2017-07-01

This paper presents an adaptive super-twisting sliding mode control (STC) along with double-loop control for voltage tracking performance of three-phase differential boost inverter and DC-link capacitor voltage regulation in grid-connected PV system. The effectiveness of the proposed control strategies are demonstrated under realistic scenarios such as variations in solar insolation, load power demand, grid voltage, and transition from grid-connected to standalone mode etc. Additional supplementary power quality control functions such as harmonic compensation, and reactive power management are also investigated with the proposed control strategy. The results are compared with conventional proportional-integral controller, and PWM sliding mode controller. The system performance is evaluated in simulation and in real-time. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

The value of residential photovoltaic systems: A comprehensive assessment

Science.gov (United States)

Borden, C. S.

1983-01-01

Utility-interactive photovoltaic (PV) arrays on residential rooftops appear to be a potentially attractive, large-scale application of PV technology. Results of a comprehensive assessment of the value (i.e., break-even cost) of utility-grid connected residential photovoltaic power systems under a variety of technological and economic assumptions are presented. A wide range of allowable PV system costs are calculated for small (4.34 kW (p) sub ac) residential PV systems in various locales across the United States. Primary factor in this variation are differences in local weather conditions, utility-specific electric generation capacity, fuel types, and customer-load profiles that effect purchase and sell-back rates, and non-uniform state tax considerations. Additional results from this analysis are: locations having the highest insolation values are not necessary the most economically attractive sites; residential PV systems connected in parallel to the utility demonstrate high percentages of energy sold back to the grid, and owner financial and tax assumptions cause large variations in break-even costs. Significant cost reduction and aggressive resolution of potential institutional impediments (e.g., liability, standards, metering, and technical integration) are required for a residential PV marker to become a major electric-grid-connected energy-generation source.

Frequency scanning-based stability analysis method for grid-connected inverter system

DEFF Research Database (Denmark)

Wang, Yanbo; Wang, Xiongfei; Blaabjerg, Frede

2017-01-01

This paper proposes a frequency scanning-based impedance analysis for stability assessment of grid-connected inverter system, which is able to perform stability assessment without using system mathematical models and inherit the superior feature of impedance-based stability criterion with conside......This paper proposes a frequency scanning-based impedance analysis for stability assessment of grid-connected inverter system, which is able to perform stability assessment without using system mathematical models and inherit the superior feature of impedance-based stability criterion...... with consideration of the inverter nonlinearities. Small current disturbance is injected into grid-connected inverter system in a particular frequency range, and the impedance is computed according to the harmonic-frequency response using Fourier analysis, and then the stability is predicted on the basis...... of the impedance stability criterion. The stability issues of grid-connected inverters with grid-current feedback and the converter-current feedback are addressed using the proposed method. The results obtained from simulation and experiments validate the effectiveness of the method. The frequency scanning...

Photovoltaic power, lithium batteries and network connection; Energia fotovoltaica, baterias de litio e conexao a rede

Energy Technology Data Exchange (ETDEWEB)

Schmiegel, A.U.; Koch, K.; Meissner, A.; Knaup, P. [Voltwerk Electronics (Germany); Jehoulet, C.; Schuh, H. [Saft Batteries (France); Landau, M.; Braun, M.; Bundenbender, K.; Geipel, R.; Vachette, C. [Fraunhofer IWES (Germany); Sauer, D.-U.; Magnor, D. [RWTH Aachen University (Germany). Institute for Solar Energy Systems - ISEA; Marcel, J.-C. [Tenosol (France)

2011-11-15

The Sun-ion, the system described in this article, combines storage technology based on the lithium ions with the high efficiency photovoltaic inverters, and supports two philosophies for personal use: off-grid, where the loads are directly connected to the inverter; and connected to the network, which makes up their own consumption when the load balancing in the network connection is zero. Performance measurements demonstrate the feasibility of the concept.

Economic evaluation of photovoltaic electric power generation connected to the grid in deregulated electric power markets; Avaliacao economica da geracao de energia eletrica fotovoltaica conectada a rede em mercados eletricos desregulados

Energy Technology Data Exchange (ETDEWEB)

Zumaran, David Richard Orosco

2000-12-01

This work presents an analysis of economic, tariff and regulating issues related to the introduction of Grid Connected Photovoltaic Systems in a deregulated electric market context; a case study for the peruvian electric market is realized. Based on the pricing system of the electric market, it is developed an economic assessment model that can be used by institutions interested in promoting this technology for generating electricity. (author)

Design of a Glenn Research Center Solar Field Grid-Tied Photovoltaic Power System

Science.gov (United States)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) designed, developed, and installed, a 37.5 kW DC photovoltaic (PV) Solar Field in the GRC West Area in the 1970s for the purpose of testing PV panels for various space and terrestrial applications. The PV panels are arranged to provide a nominal 120 VDC. The GRC Solar Field has been extremely successful in meeting its mission. The PV panels and the supporting electrical systems are all near their end of life. GRC has designed a 72 kW DC grid-tied PV power system to replace the existing GRC West Area Solar Field. The 72 kW DC grid-tied PV power system will provide DC solar power for GRC PV testing applications, and provide AC facility power for all times that research power is not required. A grid-tied system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility for use by all. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. The report concludes that the GRC West Area grid-tied PV power system design is viable for a reliable

Online model-based fault detection for grid connected PV systems monitoring

KAUST Repository

Harrou, Fouzi; Sun, Ying; Saidi, Ahmed

2017-01-01

This paper presents an efficient fault detection approach to monitor the direct current (DC) side of photovoltaic (PV) systems. The key contribution of this work is combining both single diode model (SDM) flexibility and the cumulative sum (CUSUM) chart efficiency to detect incipient faults. In fact, unknown electrical parameters of SDM are firstly identified using an efficient heuristic algorithm, named Artificial Bee Colony algorithm. Then, based on the identified parameters, a simulation model is built and validated using a co-simulation between Matlab/Simulink and PSIM. Next, the peak power (Pmpp) residuals of the entire PV array are generated based on both real measured and simulated Pmpp values. Residuals are used as the input for the CUSUM scheme to detect potential faults. We validate the effectiveness of this approach using practical data from an actual 20 MWp grid-connected PV system located in the province of Adrar, Algeria.

Online model-based fault detection for grid connected PV systems monitoring

KAUST Repository

Harrou, Fouzi

2017-12-14

This paper presents an efficient fault detection approach to monitor the direct current (DC) side of photovoltaic (PV) systems. The key contribution of this work is combining both single diode model (SDM) flexibility and the cumulative sum (CUSUM) chart efficiency to detect incipient faults. In fact, unknown electrical parameters of SDM are firstly identified using an efficient heuristic algorithm, named Artificial Bee Colony algorithm. Then, based on the identified parameters, a simulation model is built and validated using a co-simulation between Matlab/Simulink and PSIM. Next, the peak power (Pmpp) residuals of the entire PV array are generated based on both real measured and simulated Pmpp values. Residuals are used as the input for the CUSUM scheme to detect potential faults. We validate the effectiveness of this approach using practical data from an actual 20 MWp grid-connected PV system located in the province of Adrar, Algeria.

EFFECTIVE USE OF PHOTOVOLTAIC SYSTEMS IN POLISH CONDITIONS

Directory of Open Access Journals (Sweden)

Marek Niechaj

2016-11-01

Full Text Available Photovoltaic (PV systems form two groups: grid-connected ones and stand-alone ones. The first group can be divided into: centralised systems with large power (PV farms, and decentralised systems with low-power (especially prosumer ones. The second group includes systems with electric buffer sources (especially with electrochemical batteries, and those without electric buffer sources (possibly with non-electric buffer sources. Due to significant decline in price of PV modules, both of these groups are becoming increasingly common in Poland, especially grid-connected ones. Additional factor for prosumer systems is economic and legal support in a form of exemption from fees for connection to grid, lack of additional required licenses for such connection, and possible support in a form of guaranteed sale prices to grid (feed-in tariffs of electrical energy generated in system. However, in case of systems not covered by economic benefits, increasing, or even ensuring, their cost-effectiveness, requires the number of ventures regarding areas of proper installation and operation rules of PV generator from installer/user/owner of system, as well as selection of suitable tariff and rational restructuring of energy demands. Detailed analysis and conclusions of these ventures, especially for prosumer systems, is discussed in paper.

Power electronics and control techniques for maximum energy harvesting in photovoltaic systems

CERN Document Server

Femia, Nicola

2012-01-01

Incentives provided by European governments have resulted in the rapid growth of the photovoltaic (PV) market. Many PV modules are now commercially available, and there are a number of power electronic systems for processing the electrical power produced by PV systems, especially for grid-connected applications. Filling a gap in the literature, Power Electronics and Control Techniques for Maximum Energy Harvesting in Photovoltaic Systems brings together research on control circuits, systems, and techniques dedicated to the maximization of the electrical power produced by a photovoltaic (PV) so

Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System: Preprint

Energy Technology Data Exchange (ETDEWEB)

Smith, Kandler A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Saxon, Aron R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Keyser, Matthew A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lundstrom, Blake R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cao, Ziwei [SunPower Corporation; Roc, Albert [SunPower Corp.

2017-08-25

Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System: Preprint Lithium-ion (Li-ion) batteries are being deployed on the electrical grid for a variety of purposes, such as to smooth fluctuations in solar renewable power generation. The lifetime of these batteries will vary depending on their thermal environment and how they are charged and discharged. To optimal utilization of a battery over its lifetime requires characterization of its performance degradation under different storage and cycling conditions. Aging tests were conducted on commercial graphite/nickel-manganese-cobalt (NMC) Li-ion cells. A general lifetime prognostic model framework is applied to model changes in capacity and resistance as the battery degrades. Across 9 aging test conditions from 0oC to 55oC, the model predicts capacity fade with 1.4 percent RMS error and resistance growth with 15 percent RMS error. The model, recast in state variable form with 8 states representing separate fade mechanisms, is used to extrapolate lifetime for example applications of the energy storage system integrated with renewable photovoltaic (PV) power generation.

Design optimization of transformerless grid-connected PV inverters including reliability

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2012-01-01

Of the Electricity (LCOE) generated during the PV system lifetime period is minimized. The LCOE is calculated also considering the failure rates of the components, which affect the reliability performance and lifetime maintenance cost of the PV inverter. A design example is presented, demonstrating that compared...... to the non-optimized PV inverter structures, the PV inverters designed using the proposed optimization methodology exhibit lower total manufacturing and lifetime maintenance cost and inject more energy into the electric-grid and by that minimizing LCOE.......This paper presents a new methodology for optimal design of transformerless Photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal values and types of the PV inverter components are calculated such that the PV inverter Levelized Cost...

Design Optimization of Transformerless Grid-Connected PV Inverters Including Reliability

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2013-01-01

such that the PV inverter LCOE generated during the PV system lifetime period is minimized. The LCOE is also calculated considering the failure rates of the components, which affect the reliability performance and lifetime maintenance cost of the PV inverter. A design example is presented, demonstrating...... that compared to the nonoptimized PV inverter structures, the PV inverters designed using the proposed optimization methodology exhibit lower total manufacturing and lifetime maintenance cost and inject more energy into the electric-grid and by that minimizing LCOE.......This paper presents a new methodology for optimal design of transformerless photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal switching frequency as well as the optimal values and types of the PV inverter components is calculated...

Grid-connected solar electricity in France : the example of Martinique, a French overseas department

Energy Technology Data Exchange (ETDEWEB)

Melle, Y. [Tenesol (France)

2006-07-01

Tenesol has specialized in photovoltaic (PV) solar energy since 1983 with experience in grid connections, professional applications, decentralized rural electrification and solar pumping. The company's operations include the manufacture of solar panels, system design and turnkey installations backed by a comprehensive after sales service through a global network of subsidiaries. Half of Tenesol's group shareholdings belong to Electricite de France and half belong to Total. The 2 specialized subsidiaries of Tenesol are Tenesa Manufacturing and Tenesol Technologies. This presentation focused Tenesol's operations in Martinique and its financial environment of grid-connected photovoltaics. It presented Tenesol's approach for technical and economic validation of roof suitability in terms of the disc orientation of PV panels. The key figures of installing a 300 square metre 40 kWp PV system were presented along with photographs of installations in Martinique. The installations have a total installed capacity of 2.5 MWp and an annual solar electricity production of 3,375,000 kWhs, resulting in a reduction of 3,000 tons of carbon dioxide annually. figs.

Distributed photovoltaic systems - Addressing the utility interface issues

Science.gov (United States)

Firstman, S. I.; Vachtsevanos, G. J.

This paper reviews work conducted in the United States on the impact of dispersed photovoltaic sources upon utility operations. The photovoltaic (PV) arrays are roof-mounted on residential houses and connected, via appropriate power conditioning equipment, to the utility grid. The presence of such small (4-6 Kw) dispersed generators on the distribution network raises questions of a technical, economic and institutional nature. After a brief identification of utility interface issues, the paper addresses such technical concerns as protection of equipment and personnel safety, power quality and utility operational stability. A combination of experimental and analytical approaches has been adopted to arrive at solutions to these problems. Problem areas, under various PV system penetration scenarios, are identified and conceptual designs of protection and control equipment and operating policies are developed so that system reliability is maintained while minimizing capital costs. It is hoped that the resolution of balance-of-system and grid interface questions will ascertain the economic viability of photovoltaic systems and assist in their widespread utilization in the future.

大型并网光伏发电系统方案设计探讨%Discussion on the Design of Large-scale Grid-connected Photovoltaic Power Generation System

Institute of Scientific and Technical Information of China (English)

马春兰

2015-01-01

As a non-exhausted and clean energy source, the solar energy attracts worldwide attention nowadays.A grid-connected photovoltaic power generation project located in the Ruoqiang Industry Park is presented, including the design of photovoltaic power generation system and the optimization scheme, which could be a useful reference for similar pro-jects.%太阳能作为一种永不枯竭、无污染的清洁能源，已经越来越受到科技工作者们的重视，各国也在努力开发和利用太阳能。以若羌产业园区光伏并网项目为依托，介绍了光伏发电站的发电系统方案设计及其优化设计，可供类似工程参考。

Analytical Assessment of the Relationship between 100MWp Large-scale Grid-connected Photovoltaic Plant Performance and Meteorological Parameters

Science.gov (United States)

Sheng, Jie; Zhu, Qiaoming; Cao, Shijie; You, Yang

2017-05-01

This paper helps in study of the relationship between the photovoltaic power generation of large scale “fishing and PV complementary” grid-tied photovoltaic system and meteorological parameters, with multi-time scale power data from the photovoltaic power station and meteorological data over the same period of a whole year. The result indicates that, the PV power generation has the most significant correlation with global solar irradiation, followed by diurnal temperature range, sunshine hours, daily maximum temperature and daily average temperature. In different months, the maximum monthly average power generation appears in August, which related to the more global solar irradiation and longer sunshine hours in this month. However, the maximum daily average power generation appears in October, this is due to the drop in temperature brings about the improvement of the efficiency of PV panels. Through the contrast of monthly average performance ratio (PR) and monthly average temperature, it is shown that, the larger values of monthly average PR appears in April and October, while it is smaller in summer with higher temperature. The results concluded that temperature has a great influence on the performance ratio of large scale grid-tied PV power system, and it is important to adopt effective measures to decrease the temperature of PV plant properly.

Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

Directory of Open Access Journals (Sweden)

Bhavna Jain

2015-01-01

Full Text Available Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding and grid connected mode as well. In particular, a proper monitoring and control algorithm is required for transition between the modes. A wavelet based energy function is used for detection of grid disturbances as well as recovery of grid so that transition between the modes is made. To obtain good power quality LCL filter is used to reduce ripples. PLL is used for synchronization whenever mode changes from stand-alone to grid connected. Simulation results from a 10 kW wind energy conversion system are included to show the usefulness of the proposed methods. The control method is tested by generated gate pulses for single phase bridge inverter using field programmable gate array (FPGA.

Control and Modulation Techniques for a Centralized PV Generation System Grid Connected via an Interleaved Inverter

Directory of Open Access Journals (Sweden)

Gianluca Brando

2016-09-01

Full Text Available In the context of grid connected photovoitaic (PV generation systems, there are two paramount aspects regarding the Maximum Power Point Tracking (MPPT of the photovoltaic units and the continuity of the service. The most diffused MPPT algorithms are based on either perturb and observe, or on an incremental conductance approach and need both PV current and voltage measurements. Several topology reconfigurable converters are also associated with the PV plants, guaranteeing fault-tolerant features. The generation continuity can also be assured by interleaved inverters, which keep the system operating at reduced maximum power in case of failure. In this paper, an evolution of a hysteresis based MPPT algorithm is presented, based on the measurement of only one voltage, together with a novel space vector modulation suitable for a two-channel three-phase grid connected interleaved inverter. The proposed MMPT algorithm and modulation technique are tested by means of several numerical analyses on a PV generation system of about 200 kW maximum power. The results testify the validity of the proposed strategies, showing good performance, even during a fault occurrence and in the presence of deep shading conditions.

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

Directory of Open Access Journals (Sweden)

Sidra Mumtaz

Full Text Available This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG. A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms.

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

Science.gov (United States)

Mumtaz, Sidra; Khan, Laiq; Ahmed, Saghir; Bader, Rabiah

2017-01-01

This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms.

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system

Science.gov (United States)

Khan, Laiq; Ahmed, Saghir; Bader, Rabiah

2017-01-01

This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms. PMID:28877191

An algorithm for reduction of extracted power from photovoltaic strings in grid-tied photovoltaic power plants during voltage sags

DEFF Research Database (Denmark)

Tafti, Hossein Dehghani; Maswood, Ali Iftekhar; Pou, Josep

2016-01-01

strings should be reduced during voltage sags. In this paper, an algorithm is proposed for determining the reference voltage of the PV string which results in a reduction of the output power to a certain amount. The proposed algorithm calculates the reference voltage for the dc/dc converter controller......, based on the characteristics of the power-voltage curve of the PV string and therefore, no modification is required in the the controller of the dc/dc converter. Simulation results on a 50-kW PV string verified the effectiveness of the proposed algorithm in reducing the power from PV strings under......Due to the high penetration of the installed distributed generation units in the power system, the injection of reactive power is required for the medium-scale and large-scale grid-connected photovoltaic power plants (PVPPs). Because of the current limitation of the grid-connected inverter...

Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

OpenAIRE

Jain, Bhavna; Singh, Sameer; Jain, Shailendra; Nema, R. K.

2015-01-01

Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL) and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding...

Life cycle assessment of grid-connected photovoltaic power generation from crystalline silicon solar modules in China

International Nuclear Information System (INIS)

Hou, Guofu; Sun, Honghang; Jiang, Ziying; Pan, Ziqiang; Wang, Yibo; Zhang, Xiaodan; Zhao, Ying; Yao, Qiang

2016-01-01

Graphical abstract: Comparison of life cycle GHG emissions of various power sources. - Highlights: • The LCA study of grid-connected PV generation with silicon solar modules in China has been performed. • The energy payback times range from 1.6 to 2.3 years. • The GHG emissions are in the range of 60.1–87.3 g-CO_2,eq/kW h. • The PV manufacturing process occupied about 85% or higher of total energy usage and total GHG emission. • The SoG-Si production process accounted for more than 35% of total energy consumption and GHG emissions. - Abstract: The environmental impacts of grid-connected photovoltaic (PV) power generation from crystalline silicon (c-Si) solar modules in China have been investigated using life cycle assessment (LCA). The life cycle inventory was first analyzed. Then the energy consumption and greenhouse gas (GHG) emission during every process were estimated in detail, and finally the life-cycle value was calculated. The results showed that the energy payback time (T_E_P_B_T) of grid-connected PV power with crystalline silicon solar modules ranges from 1.6 to 2.3 years, while the GHG emissions now range from 60.1 to 87.3 g-CO_2,eq/kW h depending on the installation methods. About 84% or even more of the total energy consumption and total GHG emission occupied during the PV manufacturing process. The solar grade silicon (SoG-Si) production is the most energy-consuming and GHG-emitting process, which accounts for more than 35% of the total energy consumption and the total GHG emission. The results presented in this study are expected to provide useful information to enact reasonable policies, development targets, as well as subsidies for PV technology in China.

Distributed photovoltaic generation in Brazil: An economic viability analysis of small-scale photovoltaic systems in the residential and commercial sectors

International Nuclear Information System (INIS)

Holdermann, Claudius; Kissel, Johannes; Beigel, Jürgen

2014-01-01

This paper examines the economic viability of small-scale, grid-connected photovoltaics in the Brazilian residential and commercial sectors after the introduction of the net metering regulation in April 2012. This study uses the discounted cash flow method to calculate the specific investment costs that are necessary for photovoltaic systems to be economically viable for each of the 63 distribution networks in Brazil. We compare these values to the system costs that are estimated in the comprehensive study on photovoltaics that was developed by the Brazilian Association of Electric and Electronic Industries (ABINEE). In our calculation, we utilize the current electricity tariffs, including fees and taxes, which we obtained through telephone interviews and publicly available information. We obtained a second important parameter by simulating PV-systems with the program PV ⁎ Sol at the distribution company headquarters' locations. In our base case scenario that reflects the current situation, in none of the distribution networks photovoltaics is economically viable in either the commercial or residential sectors. We improved the environment for grid-connected photovoltaics in our scenarios by assuming both lower PV-system costs and a lower discount rate to determine the effect on photovoltaics viability. - Highlights: • We calculate the economic viability of photovoltaics in the residential and commercial sectors in Brazil. • The PV ⁎ Sol simulations are carried out at the headquarter locations for the 63 distribution companies. • Currently in none of the distribution networks, photovoltaics is economically viable in either the commercial or residential sectors. • We analyze how the variation of the specific investment costs and of the discount rate affects the economic viability

Solar photovoltaic (PV) energy; latest developments in the building integrated and hybrid PV systems

International Nuclear Information System (INIS)

Zahedi, A.

2006-01-01

Environmental concerns are growing and interest in environmental issues is increasing and the idea of generating electricity with less pollution is becoming more and more attractive. Unlike conventional generation systems, fuel of the solar photovoltaic energy is available at no cost. And solar photovoltaic energy systems generate electricity pollution-free and can easily be installed on the roof of residential as well as on the wall of commercial buildings as grid-connected PV application. In addition to grid-connected rooftop PV systems, solar photovoltaic energy offers a solution for supplying electricity to remote located communities and facilities, those not accessible by electricity companies. The interest in solar photovoltaic energy is growing worldwide. Today, more than 3500MW of photovoltaic systems have been installed all over the world. Since 1970, the PV price has continuously dropped [8]. This price drop has encouraged worldwide application of small-scale residential PV systems. These recent developments have led researchers concerned with the environment to undertake extensive research projects for harnessing renewable energy sources including solar energy. The usage of solar photovoltaic as a source of energy is considered more seriously making future of this technology looks promising. The objective of this contribution is to present the latest developments in the area of solar photovoltaic energy systems. A further objective of this contribution is to discuss the long-term prospect of the solar photovoltaic energy as a sustainable energy supply. [Author

Global distribution of grid connected electrical energy storage systems

Directory of Open Access Journals (Sweden)

Katja Buss

2016-06-01

Full Text Available This article gives an overview of grid connected electrical energy storage systems worldwide, based on public available data. Technologies considered in this study are pumped hydroelectric energy storage (PHES, compressed air energy storage (CAES, sodium-sulfur batteries (NaS, lead-acid batteries, redox-flow batteries, nickel-cadmium batteries (NiCd and lithium-ion batteries. As the research indicates, the worldwide installed capacity of grid connected electrical energy storage systems is approximately 154 GW. This corresponds to a share of 5.5 % of the worldwide installed generation capacity. Furthermore, the article gives an overview of the historical development of installed and used storage systems worldwide. Subsequently, the focus is on each considered technology concerning the current storage size, number of plants and location. In summary it can be stated, PHES is the most commonly used technology worldwide, whereas electrochemical technologies are increasingly gaining in importance. Regarding the distribution of grid connected storage systems reveals the share of installed storage capacity is in Europe and Eastern Asia twice as high as in North America.

Operational characteristic analysis of PV generation system for grid connection by using a senseless MPPT control

Energy Technology Data Exchange (ETDEWEB)

Lee, S.-J.; Kim, K.-H.; Park, H.-Y.; Seo, H.-R.; Park, M.; Yu, I.-K. [Changwon National Univ., SarimDong (Korea, Republic of). Dept. of Electrical Engineering

2007-07-01

In photovoltaics, the sun's light energy is captured to create electricity. One of the key issues about a photovoltaic (PV) generation system is to keep the output power of photovoltaic cells maximized under any weather conditions. In a conventional maximum power point tracking (MPPT) control method, both voltage and current coming out from PV array require feedback. The system may fail to track the MPP of a PV array when unexpected weather conditions happen. This paper proposed a novel PV output senseless (POS) control method to solve the problem. The proposed POS MPPT control method only had one factor to consider, the load current. To verify this theory, a POS MPPT control was applied to a manufactured PV generation system, and the results of the the simulated and experimental data under real weather conditions were compared and analyzed. Several tables and diagrams were presented, including the circuit diagram of a manufactured PV generation system connected to grid as well as the the specifications of the PV array and PCS used for the experiment. Reasonable results were obtained in this study. In addition, the scheme was found to be very useful in maximizing power from PV array to load with feedback of only the load current. 8 refs., 3 tabs., 15 figs.

A General Constant Power Generation Algorithm for Photovoltaic Systems

DEFF Research Database (Denmark)

Tafti, Hossein Dehghani; Maswood, Ali Iftekhar; Konstantinou, Georgios

2018-01-01

Photovoltaic power plants (PVPPs) typically operate by tracking the maximum power point in order to maximize conversion efficiency. However, with the continuous increase of installed grid-connected PVPPs, power system operators have been experiencing new challenges, like overloading, overvoltages...... on a hysteresis band controller in order to obtain fast dynamic response under transients and low power oscillation during steady-state operation. The performance of the proposed algorithm for both single- and two-stage PVPPs is examined on a 50-kVA simulation setup of these topologies. Moreover, experimental...... and operation during grid voltage disturbances. Consequently, constant power generation (CPG) is imposed by grid codes. An algorithm for the calculation of the photovoltaic panel voltage reference, which generates a constant power from the PVPP, is introduced in this paper. The key novelty of the proposed...

Grid-Optimization Program for Photovoltaic Cells

Science.gov (United States)

Daniel, R. E.; Lee, T. S.

1986-01-01

CELLOPT program developed to assist in designing grid pattern of current-conducting material on photovoltaic cell. Analyzes parasitic resistance losses and shadow loss associated with metallized grid pattern on both round and rectangular solar cells. Though performs sensitivity studies, used primarily to optimize grid design in terms of bus bar and grid lines by minimizing power loss. CELLOPT written in APL.

Three-Phase Photovoltaic Systems

DEFF Research Database (Denmark)

Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

2017-01-01

Photovoltaic (PV) technology has experienced an unprecedented growth in the last two decades, transforming from mainly an off-grid niche generation to a major renewable energy technology, reaching approximately 227 GW of capacity worldwide at the end of 2015 with a predicted extra 50 GW of new...... a hardware point of view, detailing the different PV inverter structures and topologies and discussing the different control layers within a grid-connected PV plant. Modulation schemes for various PV inverter topologies, grid synchronization, current control, active and reactive power control, maximum power...

Photovoltaic conversion in Austria: Inventory 1994

International Nuclear Information System (INIS)

Faninger, G.

1995-05-01

On January 1, 1995 photovoltaic systems with a maxiumum capacity of about 1063 kW (peak) were installed in Austria. 48% of the photovoltaic systems are connected with the grid, 24% are stand-alone systems and about 28% are small systems (<200 W) for different applications. (author)

Photovoltaic module mounting system

Science.gov (United States)

Miros, Robert H. J. [Fairfax, CA; Mittan, Margaret Birmingham [Oakland, CA; Seery, Martin N [San Rafael, CA; Holland, Rodney H [Novato, CA

2012-04-17

A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

Artificial Bee Colony Algorithm for Transient Performance Augmentation of Grid Connected Distributed Generation

Science.gov (United States)

Chatterjee, A.; Ghoshal, S. P.; Mukherjee, V.

In this paper, a conventional thermal power system equipped with automatic voltage regulator, IEEE type dual input power system stabilizer (PSS) PSS3B and integral controlled automatic generation control loop is considered. A distributed generation (DG) system consisting of aqua electrolyzer, photovoltaic cells, diesel engine generator, and some other energy storage devices like flywheel energy storage system and battery energy storage system is modeled. This hybrid distributed system is connected to the grid. While integrating this DG with the onventional thermal power system, improved transient performance is noticed. Further improvement in the transient performance of this grid connected DG is observed with the usage of superconducting magnetic energy storage device. The different tunable parameters of the proposed hybrid power system model are optimized by artificial bee colony (ABC) algorithm. The optimal solutions offered by the ABC algorithm are compared with those offered by genetic algorithm (GA). It is also revealed that the optimizing performance of the ABC is better than the GA for this specific application.

A Grid Connected Transformerless Inverter and its Model Predictive Control Strategy with Leakage Current Elimination Capability

Directory of Open Access Journals (Sweden)

J. Fallah Ardashir

2017-06-01

Full Text Available This paper proposes a new single phase transformerless Photovoltaic (PV inverter for grid connected systems. It consists of six power switches, two diodes, one capacitor and filter at the output stage. The neutral of the grid is directly connected to the negative terminal of the source. This results in constant common mode voltage and zero leakage current. Model Predictive Controller (MPC technique is used to modulate the converter to reduce the output current ripple and filter requirements. The main advantages of this inverter are compact size, low cost, flexible grounding configuration. Due to brevity, the operating principle and analysis of the proposed circuit are presented in brief. Simulation and experimental results of 200W prototype are shown at the end to validate the proposed topology and concept. The results obtained clearly verifies the performance of the proposed inverter and its practical application for grid connected PV systems.

New Markets for Solar Photovoltaic Power Systems

Science.gov (United States)

Thomas, Chacko; Jennings, Philip; Singh, Dilawar

2007-10-01

Over the past five years solar photovoltaic (PV) power supply systems have matured and are now being deployed on a much larger scale. The traditional small-scale remote area power supply systems are still important and village electrification is also a large and growing market but large scale, grid-connected systems and building integrated systems are now being deployed in many countries. This growth has been aided by imaginative government policies in several countries and the overall result is a growth rate of over 40% per annum in the sales of PV systems. Optimistic forecasts are being made about the future of PV power as a major source of sustainable energy. Plans are now being formulated by the IEA for very large-scale PV installations of more than 100 MW peak output. The Australian Government has announced a subsidy for a large solar photovoltaic power station of 154 MW in Victoria, based on the concentrator technology developed in Australia. In Western Australia a proposal has been submitted to the State Government for a 2 MW photovoltaic power system to provide fringe of grid support at Perenjori. This paper outlines the technologies, designs, management and policies that underpin these exciting developments in solar PV power.

Analysis and Design of Solar Photo voltaic Grid Connected Inverter

Directory of Open Access Journals (Sweden)

Muddasani Satyanarayana

2015-08-01

Full Text Available This paper presents common mode voltage analysis of single phase grid connected photovoltaic inverter. Many researchers proposed different grid tie inverters for applications like domestic powering, street lighting, water pumping, cooling and heating applications, however traditional grid tie PV inverter uses either a line frequency or a high frequency transformer between the inverter and grid but losses will increase in the network leading to reduced efficiency of the system. In order to increase the efficiency, with reduced size and cost of the system, the effective solution is to remove the isolation transformer. But common mode (CM ground leakage current due to parasitic capacitance between the PV panels and the ground making the system unreliable. The common mode current reduces the efficiency of power conversion stage, affects the quality of grid current, deteriorate the electric magnetic compatibility and give rise to the safety threats. In order to eliminate the common mode leakage current in Transformerless PV systm two control algorithms of multi-carrier pwm are implemented and compared for performance analysis.The shoot-through issue that is encountered by traditional voltage source inverter is analyzed for enhanced system reliability. These control algorithms are compared for common mode voltage and THD comparisons. The proposed system is designed using MATLAB/SIMULINK software for analysis.

New grid-planning and certification approaches for the large-scale offshore-wind farm grid-connection systems

Energy Technology Data Exchange (ETDEWEB)

Heising, C.; Bartelt, R. [Avasition GmbH, Dortmund (Germany); Zadeh, M. Koochack; Lebioda, T.J.; Jung, J. [TenneT Offshore GmbH, Bayreuth (Germany)

2012-07-01

Stable operation of the offshore-wind farms (OWF) and stable grid connection under stationary and dynamic conditions are essential to achieve a stable public power supply. To reach this aim, adequate grid-planning and certification approaches are a major advantage. Within this paper, the fundamental characteristics of the offshore-wind farms and their grid-connection systems are given. The main goal of this research project is to study the stability of the offshore grid especially in terms of subharmonic stability for the likely future extension stage of the offshore grids i.e. having parallel connection of two or more HVDC links and for certain operating scenarios e.g. overload scenario. The current requirements according to the grid code are not the focus of this research project. The goal is to study and define potential additional grid code requirements, simulations, tests and grid planning methods for the future. (orig.)

Task 5. Grid interconnection of building integrated and other dispersed photovoltaic power systems. Risk analysis of islanding of photovoltaic power systems within low voltage distribution networks

Energy Technology Data Exchange (ETDEWEB)

Cullen, N. [Freelance Consultant, Hillside House, Swindon SN1 3QA (United Kingdom); Thornycroft, J. [Halcrow Group Ltd, Burderop Park, Swindon SN4 0QD (United Kingdom); Collinson, A. [EA Technology, Capenhurst Technology Park, Chester CH1 6ES (United Kingdom)

2002-03-15

This report for the International Energy Agency (IEA) made by Task 5 of the Photovoltaic Power Systems (PVPS) programme presents the results of a risk analysis concerning photovoltaic power systems islanding in low-voltage distribution networks. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. Task 5 deals with issues concerning grid-interconnection and distributed PV power systems. The purpose of this study was to apply formal risk analysis techniques to the issue of islanding of photovoltaic power systems within low voltage distribution networks. The aim was to determine the additional level of risk that islanding could present to the safety of customers and network maintenance staff. The study identified the reliability required for islanding detection and control systems based on standard procedures for developing a safety assurance strategy. The main conclusions are presented and discussed and recommendations are made. The report is concluded with an appendix that lists the relative risks involved.

Study on model current predictive control method of PV grid- connected inverters systems with voltage sag

Science.gov (United States)

Jin, N.; Yang, F.; Shang, S. Y.; Tao, T.; Liu, J. S.

2016-08-01

According to the limitations of the LVRT technology of traditional photovoltaic inverter existed, this paper proposes a low voltage ride through (LVRT) control method based on model current predictive control (MCPC). This method can effectively improve the photovoltaic inverter output characteristics and response speed. The MCPC method of photovoltaic grid-connected inverter designed, the sum of the absolute value of the predictive current and the given current error is adopted as the cost function with the model predictive control method. According to the MCPC, the optimal space voltage vector is selected. Photovoltaic inverter has achieved automatically switches of priority active or reactive power control of two control modes according to the different operating states, which effectively improve the inverter capability of LVRT. The simulation and experimental results proves that the proposed method is correct and effective.

Study of Micro Grid Hybrid System of Photovoltaic and Diesel Engine

Directory of Open Access Journals (Sweden)

Novitasari Dwi

2016-01-01

Full Text Available Indonesia has abundant potentials of new and renewable energy that can be used for electricity generation, especially in rural areas which have no access for grid electricity yet. The energy resources can be from solar, water, biomass or biofuel. Many villagers still use diesel generators to produce electricity in their villages. It is considered expensive because fuel price in rural areas increases 2-3 times than the normal price due to transportation cost. Hybrid system using renewable energy resources is one of the solutions to produce electricity in affordable cost for rural area. The idea is to combine diesel generators and photovoltaic toproduce electricity. Moreover, the diesel engine fuel can be replaced with biofuel. This study will analyze the hybrid system in a small scale which consists of 1kWp photovoltaic and 3 kW diesel engine. Electric load power will vary. The system is controlled by a single bidirectional inverter whichconverts power from DC to AC and vice versa

A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

DEFF Research Database (Denmark)

Sun, Kai; Zhang, Li; Xing, Yan

2011-01-01

on improved dc bus signaling is proposed for a modular photovoltaic (PV) generation system with battery energy storage elements. In this paper, the modular PV generation system is composed of three modular dc/dc converters for PV arrays, two grid-connected dc/ac converters, and one dc/dc converter for battery......, grid-connected inversion, and islanding with constant voltage (CV) generation.The power balance of the system under extreme conditions such as the islanding operation with a full-charged battery is taken into account in this control strategy. The dc bus voltage level is employed as an information......Modular generation system, which consists of modular power conditioning converters, is an effective solution to integrate renewable energy sources with conventional utility grid to improve reliability and efficiency, especially for photovoltaic generation. A distributed control strategy based...

Performance evaluation and validation of 5 MWp grid connected solar photovoltaic plant in South India

International Nuclear Information System (INIS)

Sundaram, Sivasankari; Babu, Jakka Sarat Chandra

2015-01-01

Highlights: • A real time performance analysis with validation of the system is carried out for 5 MW p plant. • Dependence or interactions of input factors over performance responses are identified. • The topology of the PV system and the inverter technology is suggested for improved realization. • The average PV module, inverter and system efficiency are found to be 6.08%, 88.2% and 5.08%. • Average energy and exergy efficiency of the system is found to be 6.08% and 3.54%. - Abstract: The main objective of this paper is to present the validated annual performance analysis with the monitored results from a 5 MW p grid connected photovoltaic plant located in India at Sivagangai district in Tamilnadu. The total annual energy generated was 8495296.4 kW h which averages around 707941.4 kW h/month. In addition to the above, real time performance of the plant is validated through system software called RETscreen plus which employs regression analysis for validation. The measured annual average energy generated by the 5 MW p system is 24116.61 kW h/day which is appropriately close to the predicted annual average which was found to be 24055.25 kW h/day by RETscreen. The predicted responses are further justified by the value of statistical indicators such as mean bias error, root mean square error and mean percentage error. The annual average daily array yield, corrected reference yield, final yield, module efficiency, inverter efficiency and system efficiency were found to be 5.46 h/day, 5.128 h/day 4.810 h/day, 6.08%, 88.20% and 5.08% respectively. The overall absolute average daily capture loss and system loss of the particular system under study is 0.384 h/day and 0.65 h/day respectively. A comparison is also made between the performance indices of solar photovoltaic system situated at other locations from the literature’s published. Furthermore the effect of input factors over the output of the system is emphasized by regression coefficients obtained

System performance of a three-phase PV-grid-connected system installed in Thailand. Data monitored analysis

International Nuclear Information System (INIS)

Boonmee, Chaiyant; Watjanatepin, Napat; Plangklang, Boonyang

2009-01-01

PV-grid-connected systems are worldwide installed because it allows consumer to reduce energy consumption from the electricity grid and to feed the surplus energy back into the grid. The system needs no battery so therefore the system price is very cheap comparing to other PV systems. PV-grid-connected systems are used in buildings that already hooked up to the electrical grid. Finding efficiency of the PV-grid-connected system can be done by using a standard instrument which needs to disconnect the PV arrays from the grid before measurement. The measurement is also difficult and we lose energy during the measurement. This paper will present the system performance of a PV-grid-connected system installed in Thailand by using a monitoring system. The monitored data are installed by acquisition software into a computer. Analysis of monitored data will be done to find out the system performance without disconnecting the PV arrays from the system. The monitored data include solar radiation, PV voltage, PV current, and PV power which has been recorded from a 5 kWp system installed of amorphous silicon PV at Rajamangala University of Technology Suvarnabhumi, Nonthaburi, Thailand. The system performance of the system by using the data monitored is compared to the standard instrument measurement. The paper will give all details about system components, monitoring system, and monitored data. The result of data analysis will be fully given. (author)

Does Your Domestic Photovoltaic Energy System Survive Grid Outages?

Directory of Open Access Journals (Sweden)

Marijn R. Jongerden

2016-09-01

Full Text Available Domestic renewable energy systems, including photovoltaic energy generation, as well as local storage, are becoming increasingly popular and economically feasible, but do come with a wide range of options. Hence, it can be difficult to match their specification to specific customer’s needs. Next to the usage-specific demand profiles and location-specific production profiles, local energy storage through the use of batteries is becoming increasingly important, since it allows one to balance variations in production and demand, either locally or via the grid. Moreover, local storage can also help to ensure a continuous energy supply in the presence of grid outages, at least for a while. Hybrid Petri net (HPN models allow one to analyze the effect of different battery management strategies on the continuity of such energy systems in the case of grid outages. The current paper focuses on one of these strategies, the so-called smart strategy, that reserves a certain percentage of the battery capacity to be only used in case of grid outages. Additionally, we introduce a new strategy that makes better use of the reserved backup capacity, by reducing the demand in the presence of a grid outage through a prioritization mechanism. This new strategy, called power-save, only allows the essential (high-priority demand to draw from the battery during power outages. We show that this new strategy outperforms previously-proposed strategies through a careful analysis of a number of scenarios and for a selection of survivability measures, such as minimum survivability per day, number of survivable hours per day, minimum survivability per year and various survivability quantiles.

Photovoltaics fundamentals, technology and practice

CERN Document Server

Mertens, Konrad

2013-01-01

Concise introduction to the basic principles of solar energy, photovoltaic systems, photovoltaic cells, photovoltaic measurement techniques, and grid connected systems, overviewing the potential of photovoltaic electricity for students and engineers new to the topic After a brief introduction to the topic of photovoltaics' history and the most important facts, Chapter 1 presents the subject of radiation, covering properties of solar radiation, radiation offer, and world energy consumption. Chapter 2 looks at the fundamentals of semiconductor physics. It discusses the build-up of semiconducto

Integration of Hybrid PV/Wind Generation System Using Fuzzy MPPT in Grid Connected System for Remote Area

Directory of Open Access Journals (Sweden)

Soedibyo

2016-01-01

Full Text Available Photovoltaic and wind are renewable energy resources that widely used and grow rapidly in fulfilling electricity demand. Powers from both technologies depend on sunlight intensity and wind speed. For small scale power generation, DC voltage from both technologies is low and requires step-up converter to raise DC voltage ratio before converted into AC voltage. To optimize this system, step-up converter must have high ratio and efficiency to a distance of wide voltage input. This paper proposed an operation simulation and arrangement of DC-DC converter along with DC-AC from hybrid source PV-Wind which integrated to grid utilities without using storage device. High Gain Integrated Cascade Boost (HGICB is DC-DC converter that has quadratic voltage ratio and used in this research. Then DC link connected to Voltage Source Inverter (VSI which interconnected with utility grid and controlled by current control method. The total installed capacity of hybrid source is 4.4 kW. Wind turbine uses PMSG along with full bridge rectifier. To maximize and stabilize the generated power, MPPT fuzzy is used. Result from the simulation shows that converter capable to maintain maximum power whether from PV and wind turbine which canalized to utility grid in various irradiation condition, wind speed, and grid load alteration.

The rural areas electrification with a hybrid photovoltaic systems

International Nuclear Information System (INIS)

Kocev, Kiril I.; Dimitrov, Dimitar; Tudzharov, Gjorgji

2001-01-01

Depending on a daily load demand, distance from the utility grid and the available solar energy, the rural villages electrification with a hybrid photovoltaic (PV) system can be a cheaper solution than the classic electrification, by connecting them to the utility grid. Besides PV generator, the considered hybrid system is consisted of a battery and a diesel gen set. For the concrete case - rural village with estimated daily load demand of 15.5 kWh/day, with the computer program PVFORM, which is modified for such hybrid system, were simulated a few hundreds PV systems, with different sizes of the PV generator and of the battery capacity. Analyzing the obtained results, it can be foreseen the influence of the component size on the system functionality. From the mass of possible system combinations, it is chosen one that has 42 % lower initial investment, than the initial investment for connection of the village to the utility grid. (Original)

Comprehensive synchronous reference frame discrete-time modelling of a grid-connected PV for fast DC-side voltage control

NARCIS (Netherlands)

Almeida, P.M.; Barbosa, P.G.; Duarte, J.L.; Ribeiro, P.F.

2017-01-01

This paper presents a novel comprehensive discrete-time model of a three-phase single stage grid-connected photovoltaic generation system. The detailed model is carried out on synchronous reference frame. It is shown that both converter's AC and DC-side discrete time model differs from the

High-Efficiency Photovoltaic System Using Partially-Connected DC-DC Converter

Science.gov (United States)

Uno, Masatoshi; Kukita, Akio; Tanaka, Koji

Power conversion electronics for photovoltaic (PV) systems are desired to operate as efficiently as possible to exploit the power generated by PV modules. This paper proposes a novel PV system in which a dc-dc converter is partially connected to series-connected PV modules. The proposed system achieves high power-conversion efficiency by reducing the passing power and input/output voltages of the converter. The theoretical operating principle was experimentally validated. Resultant efficiency performances of the proposed and conventional systems demonstrated that the proposed system was more efficient in terms of power conversion though the identical converter was used for the both systems.

Harmonic resonance assessment of multiple paralleled grid-connected inverters system

DEFF Research Database (Denmark)

Wang, Yanbo; Wang, Xiongfei; Blaabjerg, Frede

2017-01-01

This paper presents an eigenvalue-based impedance stability analytical method of multiple paralleled grid-connected inverter system. Different from the conventional impedance-based stability criterion, this work first built the state-space model of paralleled grid-connected inverters. On the basis...... of this, a bridge between the state-space-based modelling and impedance-based stability criterion is presented. The proposed method is able to perform stability assessment locally at the connection points of the component. Meanwhile, the eigenvalue-based sensitivity analysis is adopted to identify...

Power supply for pumping systems in northern Chile: Photovoltaics as alternative to grid extension and diesel engines

International Nuclear Information System (INIS)

Chueco-Fernandez, Francisco J.; Bayod-Rujula, Angel A.

2010-01-01

This paper examines and compares the cost-effectiveness to energize pumping systems in remote areas on northern Chile by means of photovoltaic systems, diesel engines and grid extension. Variables such as the distance to the power grid, the voltage grid, the prices of electricity and fuel, and the required investments, are taken into account. The comparison is made for wide range of variable values, distances and pumping requirements. The results obtained are useful for choosing the best alternative for the power supply of pumping systems in wells in Northern Chile. (author)

Look-Ahead Energy Management of a Grid-Connected Residential PV System with Energy Storage under Time-Based Rate Programs

Directory of Open Access Journals (Sweden)

Kyeon Hur

2012-04-01

Full Text Available This paper presents look-ahead energy management system for a grid-connected residential photovoltaic (PV system with battery under critical peak pricing for electricity, enabling effective and proactive participation of consumers in the Smart Grid’s demand response. In the proposed system, the PV is the primary energy source with the battery for storing (or retrieving excessive (or stored energy to pursue the lowest possible electricity bill but it is grid-tied to secure electric power delivery. Premise energy management scheme with an accurate yet practical load forecasting capability based on a Kalman filter is designed to increase the predictability in controlling the power flows among these power system components and the controllable electric appliances in the premise. The case studies with various operating scenarios demonstrate the validity of the proposed system and significant cost savings through operating the energy management scheme.

Determining Maximum Photovoltaic Penetration in a Distribution Grid considering Grid Operation Limits

DEFF Research Database (Denmark)

Kordheili, Reza Ahmadi; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

2014-01-01

High penetration of photovoltaic panels in distribution grid can bring the grid to its operation limits. The main focus of the paper is to determine maximum photovoltaic penetration level in the grid. Three main criteria were investigated for determining maximum penetration level of PV panels...... for this grid: even distribution of PV panels, aggregation of panels at the beginning of each feeder, and aggregation of panels at the end of each feeder. Load modeling is done using Velander formula. Since PV generation is highest in the summer due to irradiation, a summer day was chosen to determine maximum......; maximum voltage deviation of customers, cables current limits, and transformer nominal value. Voltage deviation of different buses was investigated for different penetration levels. The proposed model was simulated on a Danish distribution grid. Three different PV location scenarios were investigated...

Seawater pumping as an electricity storage solution for photovoltaic energy systems

International Nuclear Information System (INIS)

Manfrida, Giampaolo; Secchi, Riccardo

2014-01-01

The stochastic nature of several renewable energy sources has raised the problem of designing and building storage facilities, which can help the electricity grid to sustain larger and larger contribution of renewable energy. Seawater pumped electricity storage is proposed as a good option for PV (Photovoltaic) or solar thermal power plants, located in suitable places close to the coast line. Solar radiation has a natural daily cycle, and storage reservoirs of limited capacity can substantially reduce the load to the electricity grid. Different modes of pump operation (fixed or variable speed) are considered, the preliminary sizing of the PV field and seawater reservoir is performed, and the results are comparatively assessed over a year-long simulated operation. The results show that PV pumped storage, even if not profitable in the present situation of the renewable energy Italian electricity market, is effective in decreasing the load on the transmission grid, and would possibly be attractive in the future, also in the light of developing off-grid applications. - Highlights: • A grid-connected seawater pumping system using photovoltaic power is proposed and its performance analyzed. • Year-round simulations are run with different sizes of photovoltaic field and reservoir. • An analysis is run about the profitability of the storage system, examining performance indexes and the cost of plant. • The system proposed appears near to attract the interest of the market

Nonlinear adaptive control of grid-connected three-phase inverters for renewable energy applications

Science.gov (United States)

Mahdian-Dehkordi, N.; Namvar, M.; Karimi, H.; Piya, P.; Karimi-Ghartemani, M.

2017-01-01

Distributed generation (DG) units are often interfaced to the main grid using power electronic converters including voltage-source converters (VSCs). A VSC offers dc/ac power conversion, high controllability, and fast dynamic response. Because of nonlinearities, uncertainties, and system parameters' changes involved in the nature of a grid-connected renewable DG system, conventional linear control methods cannot completely and efficiently address all control objectives. In this paper, a nonlinear adaptive control scheme based on adaptive backstepping strategy is presented to control the operation of a grid-connected renewable DG unit. As compared to the popular vector control technique, the proposed controller offers smoother transient responses, and lower level of current distortions. The Lyapunov approach is used to establish global asymptotic stability of the proposed control system. Linearisation technique is employed to develop guidelines for parameters tuning of the controller. Extensive time-domain digital simulations are performed and presented to verify the performance of the proposed controller when employed in a VSC to control the operation of a two-stage DG unit and also that of a single-stage solar photovoltaic system. Desirable and superior performance of the proposed controller is observed.

Photovoltaic power generation system with photovoltaic cells as bypass diodes

Science.gov (United States)

Lentine, Anthony L.; Nielson, Gregory N.; Tauke-Pedretti, Anna; Cruz-Campa, Jose Luis; Okandan, Murat

2017-11-28

A photovoltaic power generation system that includes a solar panel is described herein. The solar panel includes a photovoltaic sub-module, which includes a group of microsystem enabled photovoltaic cells. The group includes a first string of photovoltaic cells, a second string of photovoltaic cells, and a differing photovoltaic cell. Photovoltaic cells in the first string are electrically connected in series, and photovoltaic cells in the second string are electrically connected in series. Further, the first string of photovoltaic cells, the second string of photovoltaic cells, and the differing photovoltaic cell are electrically connected in parallel. Moreover, the differing photovoltaic cell is used as a bypass diode for the first string of photovoltaic cells and the second string of photovoltaic cells.

Optimal Power Scheduling for a Grid-Connected Hybrid PV-Wind-Battery Microgrid System

DEFF Research Database (Denmark)

Hernández, Adriana Carolina Luna; Aldana, Nelson Leonardo Diaz; Savaghebi, Mehdi

2016-01-01

mathematical model, wherein the cost of energy purchased from the main grid is minimized and profits for selling energy generated by photovoltaic arrays are maximized by considering both physical constraints and requirements for a feasible deployment in the real system. The optimization model is tested...

Photovoltaic technologies for commercial power generation

International Nuclear Information System (INIS)

Carlson, D.E.

1990-01-01

Photovoltaic power generation is an attractive source of energy since it involves the direct conversion of sunlight into electricity with no moving parts and no pollution. Following the demonstration of the first solar cell 35 years ago at Bell Laboratories, a steady stream of scientific and commercial progress has led to a rapid increase in applications in recent years. The first commercial application of solar cells occurred more than 20 years ago when they were used to supply power for space satellites, and even today photovoltaic arrays are used to supply electricity for most satellites and space probes. This paper reviews the status of the various photovoltaic technologies as well as present applications. The prospects for both distributed and central station grid-connected systems are discussed. The paper concludes with a discussion of the institutional and political factors that will affect the introduction of grid-connected photovoltaic power systems

Eliminating Ground Current in a Transformerless Photovoltaic Application

DEFF Research Database (Denmark)

Lopez, Ocar; Freijedo, Francisco D.; Yepes, Alejandro G.

2010-01-01

For low-power grid-connected applications, a singlephase converter can be used. In photovoltaic (PV) applications, it is possible to remove the transformer in the inverter to reduce losses, costs, and size. Galvanic connection of the grid and the dc sources in transformerless systems can introduce...

Technology fundamentals: photovoltaic systems

International Nuclear Information System (INIS)

Quaschning, V.

2006-01-01

The generation of electric power from photovoltaic systems is described in detail. The mechanism of operation of solar cells is described in terms of photons, electrons, charge carriers and charge separation. The various cells, modules, technical terms and related technology are discussed. The chemical elements used in solar cells are mentioned and the manufacturing processes described. The technical advantages of the newer thin-film modules over the traditional silicon cells are given but at present manufacturing cost is limiting their production. Both stand-alone and grid-connected PV systems are described. The potential market for PV systems is discussed. It is suggested that PV could eventually meet the total global electric power demand. (author)

Off-grid photovoltaic vehicle charge using second life lithium batteries: An experimental and numerical investigation

International Nuclear Information System (INIS)

Tong, Shi Jie; Same, Adam; Kootstra, Mark A.; Park, Jae Wan

2013-01-01

Highlights: ► We have examined the feasibility of a second life battery pack for an off-grid photovoltaic vehicle charging system. ► The second life battery successfully achieved the desired function using simple control methods. ► The system has been modeled using equivalent circuit techniques. ► The model can simulate the system’s performance under different application scenarios. - Abstract: Partially degraded lithium batteries from automotive applications, also known as second life batteries, are becoming more available for secondary applications due to the increasing market share of plug-in hybrid and electric vehicles. This study examines the feasibility of installing a second life battery pack in an off-grid photovoltaic vehicle charging system. The system was constructed using a photovoltaic array to charge a battery pack via a maximum power point tracking controller and later charge a vehicle via an inverter. The battery pack was configured using 135 second life LiFePO 4 based battery cells, selected based on remaining capacity, connected to form a nine parallel by 15 serial battery pack with accessible storage capacity of 13.9 kW h. Experimental results show that the proposed second life battery system successfully achieves the desired function with a simple system structure and control methods. A numerical simulation was performed by constructing an equivalent system model, where the photovoltaic array and battery pack were modeled using equivalent circuit techniques. The model was parameterized and validated via testing of the system. Coupled with weather data, the model can simulate the system’s performance under different application scenarios. The numerical investigation reveals that the proposed system, using second life batteries, can achieve similar performance to systems using new lithium batteries, but at a reduced cost

PVUSA: The value of photovoltaics in the distribution system. The Kerman Grid-Support Project

Energy Technology Data Exchange (ETDEWEB)

Wenger, H.J.; Hoff, T.E. [Pacific Energy Group, Walnut Creek, CA (United States)

1995-05-01

As part of the Photovoltaics for Utility Scale Applications Applications (PVUSA) Project Pacific Gas Electric Company (PG&E) built the Kerman 500-kW photovoltaic power plant. Located near the end of a distribution feeder in a rural section of Fresno County, the plant was not built so much to demonstrate PV technology, but to evaluate its interaction with the local distribution grid and quantify available nontraditional grid-support benefits (those other than energy and capacity). As demand for new generation began to languish in the 1980s, and siting and permitting of power plants and transmission lines became more involved, utilities began considering smaller, distributed power sources. Potential benefits include shorter construction lead time, less capital outlay, and better utilization of existing assets. The results of a PG&E study in 1990/1991 of the benefits from a PV system to the distribution grid prompted the PVUSA Project to construct a plant at Kerman. Completed in 1993, the plant is believed to be the first one specifically built to evaluate the multiple benefits to the grid of a strategically sited plant. Each of nine discrete benefits were evaluated in detail by first establishing the technical impact, then translating the results into present economic value. Benefits span the entire system from distribution feeder to the generation fleet. This work breaks new ground in evaluation of distributed resources, and suggests that resource planning practices be expanded to account for these non-traditional benefits.