Experimental Realization of a Single-Phase Five Level Inverter for PV Applications

voltage-controlled, single-phase, five-level inverter for photovoltaic systems using semiconductor power devices is proposed. Use of a unique, multilevel voltage source configuration allows the production of high voltage, low harmonic distortion AC outputs without using transformers or series-associated synchronized switching devices. The typical role of multi-level inverters is to generate the desired AC voltage from multiple DC voltage rails. Therefore multi-level inverters can provide high power AC outputs with good efficiency. The inverter design proposed here has superior voltage regulation, a low-distortion output and improved efficiency compared to existing multi-level inverters. Complete functionality has been verified using both MATLAB/SIMULINK simulation software and experimental trial

Contribution au Développement de Techniques de Recherche de la Topologie Optimale d’un Générateur Photovoltaïque

This thesis proposes a generalized technique to minimize power losses of PV arrays connected in Total Cross-Tied (TCT), under both current and voltage mismatch effects. The proposed method is based on the classification of the electrical data of the PV modules composing the photovoltaic array in order to identify the mismatch type, then applying an arrangement of the PV modules according to the mismatch type found. The design process of the proposed algorithm is detailed and its validity and performance are verified under different mismatch scenarios. The efficiency enhancement is verified for different mismaths cases and the computed results reveal that the proposed algorithm can achieve a great improvement in the PV array power. Furthermore, a comparative study with SuDoKu and genetic algorithms (GA) are performed. The obtained results under highlighted the superiority of the proposed method in comparison to the compared ones. The enhancement resides in the implementation simplicity as well as in the minimization of the number of infection points indicating smooth I-V and P-V characteristic curves

Experimental Validation of a Thirteen Level H-Bridge Photovoltaic Inverter Configuration

Highly efficient and compact multilevel inverters are desirable in many applications such as wind farms, solar energy harvesting and electric vehicles. The authors present a single-phase thirteen level inverter control method employing semiconductor power devices for photovoltaic applications. The unique configuration of source inverters with multilevel voltage capabilities enables large voltages together with minimal harmonic distortion without the employment of associated harmonized switching devices or transformers. A multilevel inverter is commonly used to create a desired voltage from several dc voltage levels. Therefore multilevel inverters can satisfy the large electric power requirements for high power devices. The proposed inverter system based on a simple Hbridge inverter structure provides accurate voltage control and excellent efficiency. The proposed inverter is demonstrated using MATLAB/SIMULINK simulation software and experimental validation is executed using high-efficiency ARM controlle

Improved dynamic reconfiguration strategy for power maximization of TCT interconnected PV arrays under partial shading conditions

In photovoltaic (PV) systems, partial shading is a major issue that may cause power losses, hot spots, and PV modules damage. Thus, PV array dynamic reconfiguration approaches based on irradiance equalization (IEq) between rows have been proposed to alleviate the shading effect thereby improving PV power production. However, the existing IEq-based reconfiguration techniques focus only on the minimization of row current error, without taking into consideration the voltage effect, which in turn, may result in power losses. In this regard, an improved reconfiguration strategy is proposed in the present paper to maximize the power production of a TCT interconnected PV array operating under partial shading conditions. The proposed strategy aims to achieve a PV array reconfiguration that mitigates the droop voltage issue by considering irradiance levels in both rows and columns. An in-depth investigation of a typical PV module and TCT module is provided, demonstrating that there are cases where the partial shading does not affect the PV module current but the operating voltage. In addition, an analysis highlighting the limitations of the IEq technique regarding the droop voltage issue is presented. Furthermore, mathematical development is established for deriving the objective function of the proposed strategy. The efficiency of the proposed reconfiguration strategy is assessed through experimental tests carried out on a 20 MWp PV station in Ain El-Melh, Algeria. The obtained results reveal that the proposed method overcomes the weaknesses of the existing IEq strategy and ensures power production higher than the TCT and IEq configurations by 17.25% and 19.34%, respectively

A novel single-phase thirteen level inverter for photovoltaic application

This paper proposed a Single-Phase 13-level inverter with voltage control method using semiconductor power devices for photovoltaic systems. The multilevel voltage source inverters unique configuration allows them to make high voltages with low harmonics without use of transformers or series associated synchronized switching devices. The general role of the multilevel inverter is to synthesize a desired voltage from several levels of dc voltages for these reason multilevel inverters can simply provide the high power required of a large electric drives. The proposed inverter system gives superior voltage regulation, smooth results and efficiency compared to multi-level inverters. The inverter is capable of producing thirteen levels of output voltage levels (Vpv, 5Vpv/6, 4Vpv/6, 3Vpv/6, 2Vpv/6, Vpv/6, 0, -Vpv/6, -2Vpv/6, -3Vpv/6, -4Vpv/6, -5Vpv/6, -Vpv). The proposed inverter was demonstrated by using simulation of MATLAB/SIMULINK software

Maximum Power Point tracking for a stand-alone photovoltaic system using Artificial Neural Network

This paper presents an intelligent method to extract the maximum power from the photovoltaic panel using artificial neural network (ANN). The inputs data required for training the ANN controller are obtained from real weather conditions and the desired output is obtained from perturb and observe (P&O) method. The proposed model is capable to improve the dynamic response and steady-state performance of the system, provides an accurate identification of the optimal operating point and an accurate estimation of the maximum power from the photovoltaic panels. The proposed ANN model is compared with conventional P&O model and shown that ANN controller could increase the power output by approximately 20%. The system is simulated and studied using MATLAB software

Experimental realization of a single-phase five level inverter for PV applications

A voltage-controlled, single-phase, five-level inverter for photovoltaic systems using semiconductor power devices is proposed. Use of a unique, multilevel voltage source configuration allows the production of high voltage, low harmonic distortion AC outputs without using transformers or series-associated synchronized switching devices. The typical role of multi-level inverters is to generate the desired AC voltage from multiple DC voltage rails. Therefore multi-level inverters can provide high power AC outputs with good efficiency. The inverter design proposed here has superior voltage regulation, a low-distortion output and improved efficiency compared to existing multi-level inverters. Complete functionality has been verified using both MATLAB/SIMULINK simulation software and experimental trials

Control of Grid Connected PMSG-Based Wind Turbine System with Back-To-Back Converter Topology Using Resonant Controller

This paper presents modeling and control strategy for the grid connected wind turbine system based on Permanent Magnet Synchronous Generator (PMSG). The considered system is based on back-to-back converter topology. The Grid Side Converter (GSC) achieves the DC bus voltage control and unity power factor. The Machine Side Converter (MSC) assures the PMSG speed control. The PMSG is used as a variable speed generator and connected directly to the turbine without gearbox. The pitch angle control is not either considered in this study. Further, Optimal Tip Speed Ratio (OTSR) based MPPT control strategy is used to ensure the most energy efficiency whatever the wind speed variations. A filter (L) is put between the GSC and the grid to reduce current ripple and to improve the injected power quality. The proposed grid connected wind system is built under MATLAB/Simulink environment. The simulation results show the feasibility of the proposed topology and performance of its control strategies