Analysis for Impacts of Internal Impedance on the Load Characteristic of a Permanent Magnet Synchronous Generator

Abstract

The load characteristic analysis of permanent magnet synchronous generator is presented. An internal impedance mathematic model of the generator was built with phasor analysis method for analyzing the relationship between exterior voltage characteristic or voltage regulation rate, active power and armature reactance. The research results demonstrated that the internal impedance of generator has both current and power factor angle negative feedback characteristic, which makes the voltage regulation rate be improved to a certain extent and the improved effect lying on both the direct-axis armature reactance under condition of an inductive load and the quadrature-axis armature reactance under resistive load. Additionally, an optimal range of the armature reactance being of less voltage regulation rate was determined according to numerical calculation and analysis. An experimental result based on the experimental measurement and data analysis of exterior voltage characteristic corresponds to the theoretical calculation demonstrated the correctness of the research model based upon the armature reaction analysis. Those can provide the theoretically guidance to the electromagnetic design of permanent magnet generator.