Three-phase photovoltaic grid-connected inverter with LCL based on current deadbeat control and PI control

Photovoltaic energy has been a hot spot of development in each country, while the inverter is a key component of photovoltaic power generation systems and networks. In order to improve the performance of the entire system, the paper proposes a three - phase photovoltaic grid-connected PWM inverter which is controlled by current deadbeat and PI algorithm. The simulation system is established by Matlab/Simulink and the PWM inverter is controlled by the combination of current deadbeat control and PI control. Compare the inverter voltage and current with the gird voltage when the three-phase symmetrical load is connected to the system. The harmonic of the three-phase inverter current is also analyzed. The results show that the combination of current deadbeat and PI algorithm gets some merits. The algorithm has a fast dynamic response. The algorithm also gets small overshoot, fast rise time, and steady static error. The system dynamics immunity is good. It tracks the grid voltage well and gets small waveform distortion.