Inverter Control Strategy Based on Improved Deadbeat Control and QPR Compound

Abstract

In the process of photovoltaic power generation, it is particularly important to choose a suitable inverter control strategy. Aiming at problems such as the poor dynamic response of the traditional controller in the three-phase LCL grid-connected inverter, the current harmonic disturbance caused by the grid voltage distortion and the inability to achieve the optimal tracking of the AC quantity, this paper presented a method to control voltage by fuzzy PI, control current by discrete QPR and improved DBC. In the voltage outer loop, the fuzzy control principle was used to adjust the P and I parameters in real time, and its output was used as the reference value for the current inner loop. In the current inner loop, the repeated control improved deadbeat and discretized form of QPR were used for compound control. The simulation results show that the control strategy greatly improves the distortion of the grid-connected current, which can optimally track the AC volume, and makes the entire system have good stability and dynamic response capabilities.