Effect of Static Eccentricity on the Mean Values of the Inductances of PMSMs

Permanent Magnet Synchronous Machines are receiving always wider adoption in several fields and, therefore, detection of mechanical faults for these machines, such as eccentricity, represents one of the main focuses of condition monitoring techniques. Although external sensors are typically used for this purpose, eccentricity has also a direct effect on the machine inductances that can be estimated by means of voltage and current measurements. In this work, the influence of static eccentricity on the mean values of the self-inductances of a PMSM is proposed by using an exact solution to the Modified Winding Function Approach typically used for mathematical modeling of inductances. After presenting a mathematical model of the inductance mean values, validation is proposed by means of both Finite Element Analysis and numerical evaluation on a concentrated winding machine.