Nondestructive Estimation of Permanent Magnet Magnetization Using Measured Value of Leakage Flux Originating from PMSM Rotor

Manufacturing mass-produced machines of the permanent magnet synchronous motors (PMSMs) include post-assembly magnetization process. Because the performance of PMSMs depends on the quality of permanent magnets (PMs), the estimation of PM magnetization is important process. Several magnetization estimation methods for pre-assembly magnetization have been proposed. However, no method for post-assembly magnetization had been proposed to estimate the magnetization distribution, which includes the magnetic nonlinearity of the magnetic circuit. In this paper, the magnetization estimation method using the Leakage flux derived from the magnetic circuit (MELF) is proposed. The performance of the proposed method (MELF) is verified using actual rotor of IEEJ D-model which is one of the benchmarks PMSMs.