| Photovoltaic inverter is a vital part of photovoltaic power generation system. Its work efficiency, output waves, reliability and other impact indicator will gradually become the key to the development of photovoltaic power generation technology. Currently, the quality of output waveform of the traditional non-pure sinusoidal inverter contains more odd harmonics interference that can easily affect the normal operation of electrical equipment. The output put in the pubic grid will cause pollution and other serious consequences.Due to solving non-pure inverter's shortcomings and deficiencies, the paper designed and made a kind of pure sinusoidal inverter, which used DSP (Digital Signal Processing)that is from PICCOLO series as inverting controller and adopted high-frequency inverting structure for realizing DC to AC. The DC booster adopted push-pull mode with controller by SG3525.The booster achieves the advantages of high energy conversing efficiency. And full-bridge inverter controlled by unipolar SPWM (Sinusoidal Pulse Width Modulation) algorithm, which had high precision and could reduce the harmonic interference. System controller adopted PI control strategy with proportion and feed-forward to reduce the harmonic components further, improve the quality of output waveform, ensure the stability and reliability.Simulation was carried out by using PSim6(Power Sim6),and then experimental prototype of inverter system was made out. Experimental waveforms and measured datas show that the designed inverter is simple, low cost, high power conversing efficiency, the quality of output waves is well, with high static and dynamic characteristics, reaching the requirements.
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