Solar Photovoltaic Energy Conversion System Research Articles

A Survey on the Integration of Solar Photovoltaic Energy Conversion Systems into Commercial and Industrial Electrical Energy Usage

A Survey on the Integration of Solar Photovoltaic Energy Conversion Systems into Commercial and Industrial Electrical Energy Usage

Simulation based study of Maximum Power Point Tracking and Frequency Regulation for Stand-alone Solar Photovoltaic Systems

The main objective of this paper is to develop a simulation model of stand-alone solar photovoltaic (PV) system based on mathematical models. A maximum power point tracking (MPPT) algorithm based on incremental conductance method is applied to extract the maximum power from solar PV energy conversion system. A DC/DC boost converter allows the MPPT to control the intermediate voltage. To regulate to voltage at load side a voltage source converter (VSC) based controller is applied to generate the pulse signal for three-phase inverter. The frequency regulation controller is developed based on conventional phase locked loop (PLL) system along with resistive dumping loads. A simulation model based on mathematical model Matlab®/Simulink®/SimPower® is constructed interface. Results using from simulation are stated to demonstrate the behaviour of stand alone solar PV energy conversion system.

Recent developments in the design of Hybrid Photovoltaic–Thermoelectric Generators: A Review

Photovoltaic cells do not convert sufficient amount of solar irradiation into electrical energy. A big amount of solar irradiation is unexploited in the form of thermal energy in case of solar photovoltaic energy conversion system. To make this conversion more efficient and effective, Hybrid photovoltaic and thermoelectric system (PV-TEG) can be used. In this system, there are two types of energy conversion involved. First is converting energy of solar irradiation into electricity by means of photovoltaic system and other is the conversion of waste heat of PV system into electricity via Thermoelectric Generator (TEG). Moreover, hybrid PV-TEG system is environmentally responsive and has no harmful impacts on environment. Hybrid PV-TEG system upturns the total dependability without degrading the quality of power produced. In this manuscript, summary of the prior works regarding progress of technological innovation in the hybrid PV-TEG structures is discussed. The scope for future work in utilizing this technology is also discussed.

SCHEMING OF CONTROLLER FOR SINGLE STAGE SOLAR PV FED BLDC MOTOR-DRIVEN WATER PUMP

To optimize the solar photovoltaic (PV) generated power using a maximum power point tracking (MPPT) technique, a DC-DC conversion stage is usually required in solar PV-fed water pumping which is driven by a brushless DC (BLDC) motor. This power reformation stage leads to an increased cost, size, difficulty, and decreased efficiency. As a unique solution, this work addresses a single-stage solar PV energy conversion system feeding a BLDC motor pump, which eliminates the DC-DC conversion stage. A simple control technique capable of operating the solar PV array at its peak power using a common voltage source inverter (VSI), is proposed for BLDC motor control. The proposed control eliminates the BLDC motor phase current sensors. No supplementary control is associated with the speed control of the motor pump and its soft start. The speed is controlled through the optimum power of the solar PV array. The suitability of the proposed system is exhibited through its performance evaluation using MATLAB/Simulink-based simulated results. keywords: MPPT, solar PV array, BLDC motor, Water pump, Voltage source inverter (VSI)

Small scale wind & solar photovoltaic energy conversion system for DC microgrid applications

The rise in demand for electrical energy throughout the globe gives a significant rise in new power generating sources. The Wind and Solar Photovoltaic energy sources are the most propitious power generating sources among them. Nowadays, these sources play an important role to form a Micro Grid with the incorporation of conventional grid and energy storage facilities. This article comprises of the simulations analysis for Wind Energy Conversion System and Photovoltaic Energy System incorporated with DC load for the applications of DC Microgrid. The mathematical model of the WECS and PVES are incorporated and proposed with the Gain Scheduled Proportional Integral controller is proposed in the paper. The WECS and PVES are simulated with interfacing units for the DC load. The results are obtained for Ahmedabad, Gujarat, India for the input solar insolation and wind speed data. The materials used in small wind energy conversion systems and photovoltaic energy systems are discussed for microgrid applications. The performance for the WECS and PVES is analyzed for change in wind speed and change in solar insolation. The incorporation of GSPI controller provides stable results to maintain the voltage regulation. The results are stable over an extensive range under the unpredictable atmospheric conditions the dynamic scheduling is proposed.

Control and Automation of Hybrid Renewable Energy Harvesting System

The hybrid renewable energy harvesting and grid integration system has been proposed and validated in this work. The proposed system uses a Wind Energy Conversion System (WECS) and a Solar Photo Voltaic Energy Conversion System (SPVECS). The WECS uses Permanent Magnet Synchronous Generator (PMSG) driven by a wind turbine. The variable frequency and variable voltage output of PMSG is rectified by Diode Bridge Rectifier (DBR) and stepped up by Super Lift Luo Converter (SLLC 1), and finally, the harvested wind energy is delivered to the Direct Current (DC) link of a Distributed Static Synchronous Compensator (DSTATCOM). Further, SPV energy is harvested by using PV modules and voltage is stepped up by another SLLC (SSLC 2), and the harvested PV energy is brought to the DC link of DSTATCOM. The DSTATCOM extends real and reactive power support to the load. The various subsystems of the proposed system have been modelled in Matrix Laboratory (MATLAB) Simulink environment and analyzed their performance.

Design and development of a low-cost system to convert solar thermal energy into electricity for households in South Africa using solar concentrators

South Africa is, due its specific latitude location in the southern hemisphere, exposed to high solar irradiation levels. Black thermal absorbers have a high absorbance for solar incident radiation, while commercial photovoltaic technology only converts about 10% of energy available in the solar spectrum. In this article, low-cost Peltier conversion cells, that are normally used for cooling purposes, and that are freely available in supply stores in South Africa, were identified as suitable conversion cells for converting thermal energy into electricity. Two prototypes of thermal-to-electricity energy conversion systems were subsequently designed and developed. Particularly, advanced pulse mode DC- to- DC conversion technology, a special electronic control system, was developed, that could extract high amounts of electrical energy from the cells and could store the energy in standard storage batteries. A 3 W and a 30 W output continuous conversion capacity system were developed. A power conversion of up to 2 W capacity per individual cell was achieved. The systems used no movable parts, and the lifespan of the systems is projected to be at least twenty years. Cost and viability analyses of the systems were performed and the results were compared to existing solar photovoltaic energy conversion systems. Combining the 30 W capacity system with a black body and reflector plate absorber system revealed a cost structure of only ZAR 0.8 per kWh, as compared with a derived ZAR 3 per kWh for a combined photovoltaic and solar geyser combination, as calculated for a ten-year term. The technology as developed is suitable to be incorporated in South African households and rural Africa applications.

A Spontaneous Control for Grid Integrated Solar Photovoltaic Energy Conversion Systems With Voltage Profile Considerations

This work introduces an anti-windup feedback second order generalized integrator (AWFSOGI) based direct power control for voltage source converter (VSC) in the grid integrated solar photovoltaic energy conversion system, for dynamic control of active and reactive powers fed into the grid. The primary aim of the control is to extract fundamental component from distorted grid conditions and to feed the power to the grid at UPF in the course of normal conditions. The control can also work towards maintaining the voltage profile by regulating the phase voltage with the help of reactive power injection and functioning a ride through operation. During all these operations, no trade-off occurs with the system power quality. The efficacy of the technique is shown in simulation and exemplified experimentally under adverse grid conditions. Under all these situations, the harmonics are well within limits according to the IEEE standard-519.

Grid tied solar PV system with power quality enhancement using adaptive generalized maximum Versoria criterion

A three phase grid tied solar photovoltaic (PV) system with power quality compensation features is presented in this paper. This system is operated to transfer power generated from solar PV array to feed linear and nonlinear loads along with compensation of several power quality (PQ) issues such as harmonics, redundant reactive power and load unbalancing. The generated DC power from PV array is converted into AC by implementing a three phase voltage source converter (VSC). In order to transfer active power and mitigate PQ problems, an efficient control technique is required for grid tied solar PV system. This work presents the use of adaptive generalized maximum Versoria criterion (AGMVC) controller for VSC used in solar PV energy conversion system. Efficient utilization of solar PV array is accomplished by using Perturb and Observe based maximum power point tracking (MPPT) algorithm. The experimental setup of grid integrated PV system is implemented in the laboratory using IGBT based VSC and DSP (dSPACE DS-1202). Performance of AGMVC control technique is verified experimentally using laboratory prototype. This control technique is compared with different conventional controllers such as synchronous reference frame theory (SRFT) and instantaneous reactive power theory (IRPT) along with recently developed weight based controllers viz. least mean square (LMS), least mean mixed norm (LMMN) and normalized kernel least mean fourth-neural network (NKLMF-NN). Numerous terms such as fundamental weight convergence, steady state error, computational complexity, phase lock loop (PLL) requirement and harmonic compensation capability are considered for comparison purpose of AGMVC with the above listed control techniques. The system performance is verified according to IEEE-519 standard.

Detailed Study of Solar Energy Conversion System using Boost Converter—a New MPPT Technique

Recent expansions in the emerging technologies have enlarged the consumption of electric power enormously which, conventionally, leads to the installation of power plants of huge capacity. So, to meet the electric power demand, the usage of renewable energy resources has become predominant in the present scenario. Solar photovoltaic energy conversion system that converts solar irradiance directly into electrical energy is a great opportunity among the available renewable energy resources as it is very abundant. In this paper, the key objective is to elucidate the detailed procedure of the maximum power-point tracking process for the solar panel with both stand-alone and grid-connected solar energy conversion system using a boost converter. The proposed system is simulated using MATLAB/Simulink, and comparative analysis shows the better performance of the proposed scheme.

CONVENTIONAL MAXIMUM POWER POINT TRACKING TECHNIQUES FOR SOLAR PHOTO VOLTAIC SYSTEMS: A CONCISE REVIEW

Renewable energy systems in general, and particularly the Solar Photo Voltaic Energy Conversion Systems (SPVECS) have received worldwide attention in the recent decades. Among the various investigative thrusts carried out in respect of SPVECS the most recognized area of research is the ‘extraction of maximum power from the Solar Photo Voltaic (SPV) system. Research in the direction of Maximum Power Point Tracking (MPPT) for extracting maximum power, for the given environmental conditions is very much appreciated and is a key phenomenon in developing efficient SPV systems. In this paper a review on the various MPPT techniques for SPV systems which have been adopted since the inception of the SPV systems up to the latest soft computing algorithms is presented. To date, there has been no critical analysis carried out on the various techniques of MPPT in terms of (1) Tracking speed, (2) Algorithm complexity, (3) Dynamic tracking under partial shading and (4) Challenges in Hardware implementation. In this work the authors have attempted to compile a categorical and comprehensive review of the various conventional and non intelligent MPPT techniques available, based on the above criteria. Further, it is envisaged that the information presented in this review will be a valuable gathering of information for practicing engineers as well as for new researchers.

Unbiased Circular Leakage Centered Adaptive Filtering Control For Power Quality Improvement of Wind–Solar PV Energy Conversion System

The hybrid renewable energy conversion systems and their increased penetration into the utility grid are intensifying the power quality (PQ) issues especially in the form of increased total harmonic distortion of voltages and currents at point of common coupling. The objective of the proposed grid-tied wind–solar photovoltaic (PV) energy conversion system is to analyze PQ issues and to mitigate them by utilizing the unbiased circular leakage centered (UCLC) adaptive filtering control. An implementation of UCLC adaptive control improves the PQ indices and system performance by overcoming the intermittency issues associated with solar and wind energies. UCLC adaptive control effectively extracts the fundamental load current component and mitigates the grid current harmonics. It has simple structure, enhanced convergence rate, and better performance with noise corrupted input and output signals. It effectively resolves the weight drift problem depicted by the conventional least mean square (LMS) control and leaky LMS control algorithm by avoiding biased estimates. The averaging theory and the deterministic stability analysis provide the relying facts of the performance of UCLC adaptive control. The extraction of maximum power from solar PV array energy and wind generation is carried out by perturb and observe scheme. A prototype is made in the laboratory and verified for environmental variations of solar insolation level, wind speed, and perturbing load demand. The PQ issues are effectively alleviated. Test results confirm the effective performance of the proposed system.

Power Loss Model and Efficiency Analysis of Three-Phase Inverter Based on SiC MOSFETs for PV Applications

This paper presents the power loss model analysis and efficiency of three-level neutral-point-clamped (3L-NPC) inverter that is widely employed in solar photovoltaic energy conversion system. A silicon carbide (SiC) 3L-NPC inverter is developed in this paper by employing wide bandgap semiconductor power devices, such as SiC MOSFET and SiC diode (SiC D). These devices are used due to their superior characteristics over silicon (Si) semiconductor devices for the reduction of inverter power losses, and as a result, an improving efficiency at the high switching frequency. Accurate and detailed power loss calculation formula and power loss distribution over switching devices of the SiC 3L-NPC inverter are derived according to the modulation technique and inverter operation. The switching energy loss of SiC MOSFET is then measured and determined experimentally via inductive clamp double pulse test (DPT) at the real working condition of the circuit. Afterward, this experimental data is used in the thermal description file of the device’s library of PLECS simulation software to determine the total power loss of SiC 3L-NPC inverter. The developed simulation model replicates the real operating conditions of the 3L-NPC inverter. This method gives results close to the practical test. Finally, the power loss of SiC 3L-NPC inverter is measured and compared with the theoretical results. Furthermore, SiC MOSFET and SiC D are employed to achieve high system efficiency at the high switching frequency. The results verify the features of SiC 3L-NPC inverter, the corresponding modulation technique used and their effects on reducing and improving power loss in solar SiC photovoltaic inverters.

Dual‐function PV‐ECS integrated to 3P4W distribution grid using 3M‐PLL control for active power transfer and power quality improvement

This study proposes a single-stage solar photovoltaic energy conversion system (PV-ECS) integrated to a three-phase four-wire (3P4W) distribution grid with dual-function capabilities, i.e. active power transfer and power quality (PQ) enhancement at the point of interaction (PoI). The PV-ECS system comprises of a solar photovoltaic array and a voltage source inverter (VSI), supplying active power (during daytime) to the distribution grid and connected single-phase and three-phase loads. Apart from transfer of power, the system also improves the PQ at the PoI by compensating reactive power and neutral current, attenuating harmonics, correcting power factor and balancing grid currents. During night, the VSI acts as a shunt active power filter mitigating PQ issues, thereby increasing the device utilisation factor. A three-phase magnitude-phase locked loop (3M-PLL) method is utilised to extract and estimate fundamental term of load currents and an incremental conductance algorithm is applied for maximum power point tracking. To demonstrate its effectiveness, the system is modelled and its performance is simulated on MATLAB and experiments are performed on a developed prototype in the laboratory.

Integrating solar photovoltaic energy conversion systems into industrial and commercial electrical energy utilization—A survey

Exploration of energy technology market and the role of innovation in solar energy form the core research hypothesis in this paper. There is a phenomenal growth experienced in solar photovoltaic (PV) energy market. Technological advancements have reduced the cost of solar PV generation and brought policy changes from governments across the globe. Among the solar energy technologies, solar PV system is becoming increasingly popular. Thus, there is a need to assess the pro-poor technology solutions, including field performance, consumer adoption, grid interconnection, energy storage and environmental impact assessment. This paper examines the technical issues and challenges of components associated with the generation of energy in solar PV plants. Emphasis is also given to solar PV modelling. Finally, the paper analyzes the important studies from the perspective of fault analysis and the need for energy storage and compiles them in a cohesive manner to highlight the research gaps. There is a possibility that highly educated consumers may misinterpret the information regarding solar energy and electricity. Hence, this paper shall provide an insight thereby making an interaction between industry-information-integration-communication with the society about new solar PV energy technology and energy management system. Furthermore, the application of Information and Communication Technology (ICT) and its benefits together with the environmental impact assessment (EIA) will be elaborated.

Single Stage Solar PV Fed Brushless DC Motor Driven Water Pump

In order to optimize the solar photovoltaic (PV) generated power using a maximum power point tracking technique, a dc–dc conversion stage is usually required in solar PV fed water pumping which is driven by a brushless dc (BLDC) motor. This power conversion stage leads to an increased cost, size, complexity, and reduced efficiency. As a unique solution, this paper addresses a single stage solar PV energy conversion system feeding a BLDC motor-pump, which eliminates the dc–dc conversion stage. A simple control technique capable of operating the solar PV array at its peak power using a common voltage source inverter is proposed for BLDC motor control. The proposed control eliminates the BLDC motor phase current sensors. No supplementary control is associated for the speed control of motor-pump and its soft start. The speed is controlled through the optimum power of solar PV array. The suitability of proposed system is manifested through its performance evaluation using MATLAB/Simulink-based simulated results and experimental validation on a developed prototype, under the practical operating conditions.

Three‐phase single‐stage grid tied solar PV ECS using PLL‐less fast CTF control technique

The main intent of this study is to integrate a solar photovoltaic (SPV) generating system to three-phase grid and to provide a clean and uninterrupted flow of power at abnormal and peak load conditions. To establish such an interface, a reliable, secure and high-performance control algorithm is the necessity. This study presents a three-phase single-stage grid tied SPV energy conversion system (SPECS) using phase locked loop-less (PLL-less) fast character of triangle function (CTF) control technique. This system configures an SPV array, voltage-source inverter (VSI), ripple filters and three-phase grid with connected linear and non-linear loads. Apart from supplying active power to the grid and connected loads, SPECS also provides functionalities of an active shunt filter such as reactive power compensation, harmonics attenuation, power factor correction, load balancing and zero voltage regulation. This system uses a single-stage perturb & observe approach for maximum power point tracking. Moreover, the VSI control is based on PLL-less fast CTF technique which enhances the functioning of SPECS. The presented system is modelled, designed and simulated on MATLAB/Simulink platform as well as its functioning is validated experimentally on a developed laboratory prototype.

A Sustainable Solar Photovoltaic Energy System Interfaced with Grid-Tied Voltage Source Converter for Power Quality Improvement

This paper deals with the design, modeling, and implementation of a photovoltaic (PV) array interfaced with a DC–DC boost converter feeding three-phase grid-tied voltage source converter. The system uses an Instantaneous Reactive Power Theory-based control algorithm and is operated in unity power factor mode. This three-phase shunt-connected solar PV energy conversion system is also used for load currents harmonics elimination, power factor correction, reactive power compensation, and grid currents balancing in a three-phase distribution system. A Perturb and Observe-based maximum power point tracking algorithm is used to generate maximum power from the PV array. This system is designed and modeled, and its performance is verified through simulation in MATLAB/Simulink. A prototype of the proposed renewable energy system is developed in the laboratory using a digital signal processor to validate its design and control.

A Multifunctional Grid-Tied Solar Energy Conversion System With ANF-Based Control Approach

This paper presents a two stage three-phase grid-interfaced solar photovoltaic (SPV) energy conversion system with an adaptive notch filter (ANF)-based control algorithm. The proposed SPV system is a multifunction grid-interfaced SPV energy conversion system, which along with the conversion of dc-power from SPV to ac mains is capable of reactive power compensation, harmonics currents elimination, and load balancing in a three-phase ac distribution system. Compared with multiple devices with different functionalities, a multifunction grid-interfaced SPV energy conversion system is capable of saving substantially capital investment, space, and maintenance cost on behalf of multifunctional features. The ANF successfully extracts a single sinusoid of a possibly nonstationary nature from harmonics corrupted load currents at point of common coupling. The control algorithm is adaptive with respect to the fundamental frequency of the system as compared with other methods, and provides instantaneous values of the fundamental signals. Simulation and experimental results verify the validity of the presented algorithm and confirms its desirable transient and steady state performances. The total harmonics distortion of grid currents is found well under IEEE-519 standard, even under nonlinear loads.

Single-stage sine-wave inverter for an autonomous operation of solar photovoltaic energy conversion system

This paper proposes a high performance single-stage inverter topology for the autonomous operation of a solar photovoltaic system. The proposed configuration which can boost the low voltage of photovoltaic (PV) array, can also convert the solar dc power into high quality ac power for driving autonomous loads without any filter. An MPPT circuit with parallel connection is implemented so that the part of the energy generated is processed by the dc–dc converter to supply dc loads. The line current total harmonic distortion (THD) obtained using this configuration is quite reasonable. The proposed topology has several desirable features such as low cost and compact size as number of switches used, are limited to four as against six switches used in classical two-stage inverters. In this paper analysis, simulation and experimental results are presented.