CURRENTS OF INDUCTION MOTOR UNDER VOLTAGE FLUCTUATIONS

Voltage fluctuations are a common occurrence in power systems. They can be regarded as a superposition of the fundamental voltage component, subharmonics and interharmonics – components at frequencies below the fundamental one or not being its integer multiple, respectively. This paper focuses on the effect of the moment of inertia of a driven unit on the subharmonics and interharmonics present in the supply current of a cage induction motor under rectangular voltage modulation. The results of a 2D finite element analysis are presented for a cage induction motor with a rated power of 3 kW.