Single Phase VSI Behavior Improvement using Combined Feedback and Feedforward Controllers

Abstract

Nowadays, the demand for power electronics technology has increased due to the importance of its applications such as power inverters. The power inverter is required to modify the DC power from PV cells to AC power. One of the most common issues of on-grid PV systems is the high variations of the generated DC voltage. This will affect the stability of the generated AC voltage at the Point of Common Coupling (PCC) with the grid. This paper combines the Feed-Forward and Feedback (FFFB) controller in a novel way to reduce the variation of the PV cells DC voltage. This paper presents both mathematical and Simulink models of single-phase voltage source inverters VSI. Then, a case study of 15% disturbance of DC-generated voltage is considered. The static and dynamic behaviour of the single-phase H-bridge inverter is analysed under different loads. The new combination is used to reduce the effect of the disturbance on the performance of the system. Also, the proposed closed-loop controller (FFFB) can reduce the overshoot by 50% less than the feedback controller only. The settling time has been improved by 41%, 61% for RL and induction motor.