Fast calculation of load conditions of permanent magnet synchronous machines using finite elements

This paper proposes a method of characteristics calculation for permanent magnet synchronous machines (PMSMs) using static finite element analysis (FEA) and steady-state dq-axis equations. The method calculates characteristics such as torque, voltage, current, inductances, etc. under any balanced steady-state load conditions. Various types of input condition can be selected to identify the load condition. For example, the characteristics are calculated at the load condition that has the smallest current amplitude and the inputted torque and frequency. The computing time of the method is small because the FEA is static. The calculated results of a 750-watt PMSM under minimum-current control and field-weakening control have agreed well with the measurements. The method is useful in PMSM development and design.