Design of a Linear Motor: An Optimization Approach Considering Motor and Inverter Losses With Different Voltage Waveforms

This article presents the design and testing of a brushless permanent magnet linear motor to be used in a compressor application. Usually, in the literature, the optimization process focuses on the motor or the inverter optimization. However, the voltage waveform generated by the inverter has direct influences on the motor and inverter losses. The methodology proposed here optimizes the motor taking into account motor and inverter losses models. In this sense, the process optimizes the efficiency of the motor and inverter set, resulting in a global optimum scenario. A two-step optimization process using a 3-D analytical MEC routine and 3-D finite element (FE) software was used to simulate the linear motor. The optimization was carried out with two different supply voltage waveforms. The first is the single pulse voltage (SPV) and the second is the sinusoidal PWM (SPWM) waveform. The designed motor was assembled and tested in a dynamometer to evaluate the motor, inverter, and set efficiencies, supplied with both voltage waveforms presenting good results.