Comprehensive Efficiency Optimization of Linear Induction Motors for Urban Transit

摘要

Due to the large air gap length, severe end effects, and the light load operating conditions during cruising, the efficiency of linear induction motors (LIMs) applied in urban transit, i.e., linear metro, is usually quite low. In order to overcome this drawback, this manuscript makes a comprehensive efficiency optimization to LIM efficiency from both motor design and control aspects. On the one hand, by analyzing the effects of different parameters on LIM performance, eight main parameters are selected as the optimization variables to achieve the optimal design of LIM through genetic algorithm (GA), so as to realize higher efficiency at rated operation point. On the other hand, considering the LIM still with low efficiency under light load, an optimal efficiency control (OEC) based on an integrated loss model, which contains both motor and inverter losses, is presented to promote the operating efficiency of LIM drive system in the whole operation area. Finally, the comprehensive efficiency optimization results are validated by related experiments on basis of one 3 kW prototype.