Research On Brushless DC Motor And Its Control Strategy In Wafer Cleaning Machine

Wafer cleaning machine have high demands on the dust-free working environment and cleaning equipment. Currently, wafer cleaning machine are drived by DC servo motor, but wearing and tearing of the carbon brush has polluted to the dust-free working environment, increasing the cost of maintenance. Rare-earth permanent magnet brushless DC motor, which takes the place of carbon brush and commutator, has high reliability, maintenance-free, and high efficiency. It is a perfect substitute of brush DC motor.The work of project includes four aspects. A) The concentrated winding brushless DC motors are researched such as the relationship between the width of surface-mount brushless motor rotor magnet and the air-gap flux density wave, and inductive method, which is a method that the brushless motor without position sensor detects the location of rotor; then the hollow-shaft brushless DC motor of wafer cleaning machine is trial-manufactured. B) The controller of BLDC motor will be developed. C) The control strategies and the improving dPID control strategy of brushless DC motor are studied, then the software is developed, simulinked and tested. D) The control strategies of torque ripple of square-wave brushless DC motor within the whole scope of speed, including low-speed, medium speed and high-speed, are studied, and the software is devloped and debugged.This paper is divided into six chapters. Chapter 1 summarizes the drive motor state of wafer cleaning machine, brushless DC motor controller, control strategy, and the requirements of the brushless DC motor control according to the production process of wafer cleaning machine. Chapter 2 analyzes the relationship between rotor magnet width of surface-mount-type brushless DC motor and air-gap flux density waveform, then researches the inductive method, and finally discusses the design and process of wafer cleaning machine brushless DC motors. Chapter 3 introduces the controller hardware structure, and presents details description of the functions of each module and the implementation method given in the design process problems and solutions, based on the DSP2407 and Mitsubishi IPM brushless motor controller. Chapter 4 studies the control strategy of wafer cleaning machine, select the improved dual-loop control strategy, then design the software of control strategy, and complement simulation and testing. Chapter 5 study how to keep down the speed torque ripple of other wave brushless motor within the scope, carry out control strategy corresponding low, medium and high-speed, and then carry out the control strategy of the software design and field commissioning and testing, give the test results. Chapter 6 summarizes Full-text.