New Approach to Improve Starting Performance of Induction Motor Based on Optimal Starting Frequency

The starting performance of induction motor (IM) has a prominent influence on the redundancy design and cost control of motor drivers. To make the starting torque as high as possible under the special setting of starting current, a new approach for improving the starting performance of three-phase IM is proposed in this paper. First, the frequency characteristic of the starting torque, which is different from the optimal starting torque per ampere (OSTPA) proposed by the author previously, is investigated based on the universal T-type equivalent model that considers the iron loss. The analysis results confirm the existence of an optimal starting frequency (OSF), which makes the starting torque much higher than that at rated frequency. Secondly, complete discussions of starting initial values are reported and discussed, including starting voltage and motor parameters. Then, the step-by-step starting algorithms based on OSF are provided. Finally, the OSF and its starting strategy are tested on a rapid control prototype system, and the comparison between computed and measured results confirms the feasibility and effectiveness of the proposed approach.