Hysteresis Based Fixed Switching Frequency Current Control of a Three Phase Grid Connected Voltage Source Inverter

Abstract

The traditional Fixed Band Hysteresis Current Control though being widely used for the current control of a grid connected system, it has the drawback of variable switching frequency. To overcome this drawback, Variable Band Hysteresis Current Control has been recommended in the literature. This paper proposes a Hysteresis based Current Control of Three Phase Grid Connected Voltage Source Inverter, wherein a single reference wave is used per phase instead of a hysteresis band. Here the upper and lower boundaries of the inductor current in each phase are either controlled by the comparator or by the switching logic based on the nature of its slope. Theoretical analysis and the MATLAB/Simulink results are included to validate the proposed method.