Design Of PV Grid-connected Simulation Device

With the gradual increase in the increasingly sharp increase in energy consumption today and the dwindling of traditional energy sources, and the use of a series of issues related to traditional energy sources, such as environmental pollution, the greenhouse effect and many other issues, the growing demand for the development of new energy big. Countries today are committed to the development of new energy such as atomic energy, wind energy, solar energy. In the recent decades of development, solar energy has been developing rapidly. As the infrastructure of the electric power industry is trying to use of solar power development to inject new vigor and vitality. The photovoltaic power generation has become the trend of the times and the key technologies for restricting the application of solar energy.Solar energy as a clean and pollution-free and large-scale development and utilization of renewable energy has broad application prospects, its application is to be a great development. Solar photovoltaic power generation is an effective means of utilization of solar energy by more and more attention. Research on solar photovoltaic power generation is a theoretical value of the practical significance of the subject. In addition, the emergence of a variety of high-performance digital signal processing chip (FPGA), a variety of advanced control strategies used in photovoltaic grid-connected inverter to become possible. Grid-connected PV solar photovoltaic use of key trends, and will certainly be a rapid development.The subject of solar photovoltaic power generation simulator development, focused on the AC inverter, including photovoltaic arrays maximum power point tracking (MPPT) control and grid current waveform control method has been studied.This article first analyzes the working principle and basic characteristics of solar photovoltaic cells, the establishment of the equivalent circuit and mathematical model of the photovoltaic cells. Describes the commonly used principle of MPPT Control Technology and its comparison argument.Focuses on the photovoltaic grid-connected inverter topology and the current control strategy, the establishment of a mathematical model of the photovoltaic grid-connected inverter, analysis and comparison of different control schemes. A number of research and analysis on the filtering of the grid-connected inverter, compared to L and LCL two filtering methods, given the design of the filter parameters.ALTERA Cyclone II EP2C35F672C6(FPGAs) as the control core of this design to the full-bridge inverter circuit for the power transform the main circuit, using sinusoidal pulse width modulation (SPWM) inverter circuit control signal, mainly in the hardware study the implementation of each module, and produced the hardware circuit of each module, combined with Protel DXP software to build debug software with the full realization of the design requirements. In this context, the core of the device of the papers on solar power generation system-grid-connected inverter, a more in-depth study, to maximize the use of solar energy as the main target, production ALTERA Cyclone II EP2C35F672C6the system control carried out theoretical and experimental study of solar power generation system, a very important practical significance.The design of photovoltaic power generation analog devices with maximum power point tracking (MPPT), the output phase and frequency to track the reference signal. The system uses a digital closed-loop feedback control, to ensure that the same frequency and phase between the transformer feedback signal and reference signal. DC-AC power conversion part of the efficiency of up to84%, the output voltage waveform distortion is less than5%, input under-voltage protection, output over-current protection, and troubleshooting automatic recovery function. Design of the L and LCL of the two filters, the experimental comparison of these two methods of filtering effect; integration of the main circuit and control circuit design experimental prototype PCB printed circuit board, PCB design process to fully consider the main circuit and control circuit integrated design of electromagnetic compatibility problems. Experiment with the load and grid experiment to prove the correctness of the control strategies and hardware design, the reliable operation of the system to security and stability.Study of each module to achieve this design, mainly in hardware, combined with Protel DXP software, the hardware circuit of each module is produced, to build and debug the software with the full realization of the design requirements. In this context, the core of the device of the papers on solar power generation system-grid-connected inverter, a more in-depth study, to maximize the use of solar energy as the main target, production ALTERA Cyclone II EP2C35F672C6the system control carried out theoretical and experimental study of solar power generation system, a very important practical significance.After nearly a year of theoretical study and painstaking research, the system can achieve the following functions:(1) has a maximum power point tracking (MPPT) function;(2) the frequency tracking function;(3) When RS=RL=30Ω when the DC-AC converter efficiency≥60%;(4) When RS=RL=30Ω, the output voltage uo distortion THD≤5%;(5) with input voltage protection function;(6) output over-current protection function;From various parts of the test results, the design of this system is entirely feasible. However, due to development time, design tasks, design standards and other reasons, there are still some deficiencies in urgent need of improvement.