Research And Design Of Novel PV-array Simulator

This thesis presents the principle of a novel photovoltaic array simulator.Firstly, the theme shows the exploitation and utilization of solar energy, then introduces the PV system and PV array, base on this ,this paper introduces the study background, significance and the research conducted home and abroad on.Secondly, this paper introduces the principle of solar cell, shows the equivalent circuit model of PV array, then analyzes the I-V, P-V output characteristics and the environment factor's affect on it. Then the mathematic model of the PV-array and the simulation model using the mathematic model is built. This work is the base of the PV array simulator.Thirdly, this thesis introduces the system configuration and its working principle. Grounding on the conventional solar array simulator, creates two improvements for it, and builds a new method for tracking the working point of the load. This method avoids using complicated arithmetic, gives attention to the performance and cost, and shows the outside environment factor's influence on the PV array.According to the requirement of the simulator, the half bridge converter is be selected as the topology of the main power circuit. The theme also analyses its working principle in detail and introduces its hardware design. Based on the two point improvement, designs a new circuit which can go through every point from zero to the maximum of the solar cell output voltage and current. Using the sample hold and compare module supports the reference point of the power circuit. Then, the theme gives the design of filter circuit, driving circuit and DC/DC converter. At last small-signal model of the power circuit has been built, and designs its control loop.At last, the thesis using a PV array simulator which its open circuit voltage is 200V, short circuit current is 7A and maximum power point output is 1kW acquires the validity of theory analysis and shows the different steady working point's experimental results of the simulator. The experimental results indicate that the PV-array's steady points tallies with the simulated I-V output curve of solar array and simulates their dynamic transformation when the load is changed.