Novel Hysteresis Regulation Strategy for a Two-level Inverter Fed Induction Motor Drive to Achieve Nearly Constant Switching Frequency

Abstract

Constant switching frequency (CSF) is an important objective to be achieved by any control strategy deployed on a Voltage Source Inverter (VSI) so that the filter design will be easier. Though the invent of Multi-Level Inverters (MLI’s), the Two-Level Inverters (TLI’s) are widely used when it comes to current control strategies. In this paper, a new hysteresis current control strategy is proposed for a TLI in order to achieve nearly CSF. In this method, the constant switching frequency is achieved by creating a Variable Band (VB), which varies according to the switching frequency average of the pole voltage. The proposed control strategy creates VB’s such that it mimics the Continuous Space Vector Pulse Width Modulation (CSVPWM) and also the Bus-Clamping Pulse Width Modulation – 60° and 30° (BCPWM60 – BCPWM30). The paper also analyses the proposed control strategy under different criteria such as current THD, dynamic performance and parameter variation. This performance of the proposed strategy is simulated using MATLAB Simulink platform and experimentally validated on a 2.2 kW, three phase, Induction Motor (IM) using dSPACE-1103 kit.