Novel vector control system using deadbeat controlled PWM inverter with output LC filter. Part-2. Controller using strictly z-transformed equations

Vector controlled AC motor drives using voltage source PWM inverters have been widely used. However, since the output voltage of voltage source PWM inverters are pulse waveforms, corona deterioration of the motor winding insulation occurs. This is because of high dv/dt pulses impressed on the beginning of the turns of the stator windings. In addition, when the motor is installed distant from the inverter, the switching surge voltage at the motor terminal become high because of reflections between the inverter and the motor. This high surge voltage also contributes to the insulation deterioration. The above mentioned problems are especially severe in case of high power drives rated more than several thousands kilowatts. To overcome these problems, the authors have previously proposed a novel vector control system using a deadbeat controlled PWM inverter with an output LC filter M. Kojima et al., (2002). In this study, in order to improve characteristics, we design the deadbeat control by using the strict z-transformed state equation in which transient of the LC filter in a discretization time is considered. In addition, experimental results are given.