Modelling and output voltage distortion with capacitive current feedback control for single phase inverter powering non‐linear load

Abstract

The pulse width modulation inverter is widely applied in independent PV renewable generation applications and uninterruptible power supplies. Many control schemes are investigated for the inverter feeding non-linear loads, aiming to achieve the desired performance. However, the model currently proposed is mostly based on a linear load, which is not suitable for the condition with the non-linear load. In this paper, the uncontrolled diode rectifier load model based on the AC and DC link power balances is analysed in detail first. Then, the rectifier inverter control system mathematical model is presented. The mathematical model derivation considers the rectifier load, especially non-linear dead zone circuit performance that is closer to practical application conditions. Based on the proposed model, the output voltage control strategy with capacitor current feedback is further given. The operating principle of the proposed model and control scheme is analysed in detail. Additionally, the conclusions are validated by simulations and experimental results.