Dynamic analysis and computer simulation of interior permanent magnet synchronous motor with intermittent loading

Abstract

This paper presents the dynamic analysis and computer simulation of interior permanent magnet synchronous motor (IPMSM) with intermittent loading. This objective was realized with the aid of MATLAB m.file function program, which is based on an explicit Runge-Kutta fourth order numerical method to solve a set of first order differential system of equations describing electrical and mechanical models of IPMSM. The IPMSM used in this research is of specifications 3-phase, 2 KW, 50 Hz, 4 poles, 240 V. The IPMSM differential equations are expressed in rotor reference frame with q- and d-axes stator currents, mechanical rotor speed, and rotor angular position as state variables. The analysis and simulation of the motor is initially done with no-load and with the parameters as given in Table 1. Subsequently, the motor was loaded and parameter variations were carried out. The result of a typical responses of the motor were obtained which showed that IPMSM has more ripples, overshoot, slower response but can carry load of up to 90 Nm. The effect of higher stator resistance shows that it minimizes the magnitude of ripple of the output characteristics (torque and power) but takes more time to attain the same steady state value. In the same vein, variation of moment of inertia has little or no effect on the output characteristics of the motor. The findings obtained in this research work as compared to other literatures showed that with the parameters recommended, an improved design and operation of IPMSM will be obtained for best performance and without unsynchronous operation due to overloading.