An Improved Fuzzy Voltage Compensation Control Strategy for Parallel Inverter

Abstract

With the rapid development of microgrids, voltage drop has become one of the focuses on the research of microgrid stability and grid-connected operation. In this article, an improved fuzzy voltage compensation control strategy (FVCC) is proposed to solve the bus voltage drop problem. This method takes the influence of feeder impedance into account, and there is no need to accurately measure the feeder impedance value. Since droop control and feeder impedance can lead to voltage drop and bus voltage instability, fuzzy control is applied to compensate bus voltage. Specifically, aiming at the voltage drop caused by droop control, an adaptive fuzzy controller is designed to automatically find suitable gain parameters to reduce the voltage difference. In addition, bus voltage gain module is added to compensate the voltage consumed by feeder impedance. The compensation only needs to measure the voltage at both ends of the line, without testing the line parameters. Finally, the simulation results show that the control strategy achieves the expected effect.