Hysteresis based voltage mode control of three phase two level inverters with constant switching frequency

This paper proposes a hysteresis-based control strategy for the voltage mode control of three-phase voltage source inverters. While preserving the fundamental nature of the hysteresis control method, a constant switching frequency is guaranteed additionally by employing a counter-based frequency limiting switching algorithm. A predefined band in the conventional hysteresis control method does not exist here; instead, the switching logic decides the switching instants of the devices. The proposed method offers a fast transient response comparable with the hysteresis control method, a well-defined harmonic spectrum and good output voltage THD. Simulation results are included to validate the proposed concept.