Super premium efficiency Line Start Permanent Magnet Synchronous Motor: Design, test and comparison

Induction motors are widely used as the workhorses for the petroleum and chemical industry. As such, their efficiency is an important issue for both the users and manufacturers. As currently designated by IEC (International Electrotechnical Commission) [1], the efficiency of induction motors is classified by four levels: standard (IE1), high (IE2), premium (IE3), and super premium (IE4) efficiency. Line Start Permanent Magnet Synchronous Motor (LSPMSM) has been researched and designed to meet the IE4 standard. With the equivalent circuit analysis and Finite Element Analysis (FEA), the starting and steady-state running performance have been scrutinized. To verify the design model and the feasibility of reaching super premium efficiency level, two 4-pole LSPMSM prototypes were built and tested. Compared with Premium Efficiency Induction Motors (PEIM) with the same ratings, the prototypes yielded better performances including efficiency, power factor, temperature rise, etc., over a wide output power range. The design considerations, test results, and the comparison with the equivalent induction motors are presented in this paper.