Experimental evaluation of parameter variation effects in indirect rotor-flux oriented induction-motor drives

The paper investigates detuning effects, caused by parameter variations, in an indirect current-fed rotor-flux oriented induction motor drive aimed at operation in both the base speed region and the field-weakening region. Rotor resistance variation and magnetising inductance variation are elaborated. In contrast to the existing studies, where these detuning effects are analysed using appropriate induction machine models, the approach undertaken in this paper is purely experimental. Detuning is evaluated based on measured speed response in transient operation and measured stator current fundamental component in steady-state operation. Detuning during steady-state operation in the field-weakening region is additionally characterised with measured stator voltage fundamental component.