volume | PIER Journals

Abstract

Rotor water friction loss is a critical determinant of the overall performance and efficiency of water-filled submersible permanent magnet synchronous motors (WSPMSMs) employed in mining applications. This study analyzes the electromagnetic performance and rotor water friction loss of a 500\,kW WSPMSM using the finite element method and computational fluid dynamics (CFD), respectively. From a structural optimization perspective, the effects of the air-gap length and stator slot shape on rotor water friction loss were examined. A multi-objective optimization method incorporating rotor water friction loss was proposed, featuring variable stratification and differentiated reduction of optimization ranges. Firstly, an orthogonal array was constructed using the Taguchi method, and both electromagnetic finite element and CFD simulations were performed. Secondly, analysis of variance (ANOVA) classified design variables as significant and insignificant. Based on the multiple performance characteristic index (MPCI) analysis, the optimization ranges of two types of variables were narrowed to different extents. Finally, for significant variables, the response surface method (RSM) coupled with the non-dominated sorting genetic algorithm III (NSGA-III) was applied for precise optimization. For insignificant variables, the Taguchi method or parameter scanning was used for rapid optimization, depending on their number. By comparing the optimization results of the proposed method with those of existing methods, the effectiveness and superiority of the proposed method were verified.

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Dr. Sili Zhou

Mr. Shuo Zhou

Dr. Tianxiang Zhu

Professor Zhonggen Wang

Professor Yuanyuan Jiang

Professor Qunjing Wang