Loss Minimization And Rapid Response Control For Permanent Magnet Synchronous Linear Motor System

With the development of AC motor control technology today, the traditional DC variable speed technology has been gradually replaced by AC variable speed technology. And it has taken important effect in all areas of the national economy. The permanent magnet synchronous linear motor (PMSLM) has been widely used in the field of AC variable speed based on its high efficiency, high accuracy and so on.In recent years, the minimum loss control issues of PMSLM have been proposed and researched. The technique in the United States,Japan,Britain and some other industrialized countries has already developed some research bases, however, it has never been carried weight in China. With the energy exhaustedness and the requirement of saving energy, the minimum loss control issues of PMSLM also attract some strong attentions.Theory and practice has proved that motor efficiency is closely related to load rate. In fact, most motors operate in a condition of light-load and large part of power has been wasted. The minimal loss of PMSLM drive system had been analyzed and studied in this thesis. Through a comprehensive analysis of the motor drive system, the mathematical model of the inverter and PMSLM was established, and the relationship between the stator flux and the system loss was derived and established in theory. Therefore, the expression of the stator flux was obtained at the minimum loss so that the minimum loss control of PMSLM drive system was achieved.The objective of system minimum loss control is to find a method which is fast, stable, simple, reliable and easy to implement. However, the minimum loss control is achieved without practical method, considering the current situation of analysis about the motor loss. In this thesis, the advantages of loss model method and search optimization method were effectively combined to form a new search method, namely mixing optimization, and the comprehensive mathematical model of the two kinds of loss analysis was established. In the environment of Matlab/Simulink, the comprehensive mathematical model and the appropriate variable were used to establish the driving system simulation model. Through detecting the DC voltage and current which were at the side of the inverter and ensuring constant output power, the purpose of rapidly reaching minimum loss and optimal efficiency could be achieved. The desired result had been achieved.