The influence of inverter control algorithm and DC link voltage on the inverter switching loss

The losses of an inverter-fed induction motor drive at a given load are depending on the material and construction of the machine, the converter topology and the characteristics of semiconductor power switches, the drive control system, the inverter control (modulation) algorithm and DC link voltage. Significant component of overall drive losses are the switching losses (which are proportional to the switching frequency) of voltage source inverters. Based on simulation results the switching losses of different inverter control methods were compared in steady state at various rotor speeds and two different DC link voltages. The hysteresis and the predictive current control, furthermore the carrier based space vector and two-phase PWMs were examined and simulated. It is shown that the carrier based PWM control produces lower switching losses than other investigated control, but for higher speed the predictive control has the smallest switching losses.