Some issues on stabilization of an induction machine drive

Stability problems due to interaction between the input filter and the voltage source inverter of an induction machine drive are revised. By incorporating properties of the input filter, previous work on stabilization is extended to increase the stability margins of the drive. The strategy is to assure a small phase shift of the inverter input admittance in a frequency region around the input filter resonance frequency. It is motivated why stabilization at zero torque is more critical with a low resonance frequency of the input filter compared to a high. This is a property known from practical experience. It is also shown how dynamic stabilization gains can be used to compensate for limited control bandwidth. This way the drive can be stabilized for very large powers.