Design And Research Of Permanent Magnet Ac Servo System Experiment Platform

In recent years,with the development of power electronic technology, DSP microprocessor technology, sensor technology, rare earth permanent magnet materials and motor control theory, AC servo system gradually replaces DC servo system and it has become the servo technology mainstream.As permanent magnet synchronous motor has the advantages of wide range of speed, high positioning accuracy and static speed precision, fast dynamic response, good running stability permanent magnet AC servo system is widely used in CNC machine tools, robots,engraving machines, aeronautics & astronautics, and other multi-axis motion control systems.Before the specific products are manufactured, designing an experiment platform is necessary to study the servo motor characteristics, the multi-axis control system, the control theory and Control Strategy, and so on. It can help us to verify whether it is appropriate to choose motors, control system structures are correct and the control strategy is reasonable.It is very significant for speeding up the product development process, cost savings and so on.Intelligent robot lab of mechanical electronics engineering Institute Northeastern University is developing a polished robot. Before processing the robot, we need a test-bed to experiment and research the robot selected AC servo motors,the robot control system, and the selected control strategy.In this paper a multi-function and versatility experiment platform is designed and its control system is established. To achieve a human-computer interactive operation expediently, the human-computer interface is designed with Visual Basic language, which makes it easy to modify the control parameters and display the running state of system.On the experiment platform, we can experiment and research the characteristics of motor when the motor is given different load.We can also use modern control theory and program advanced control algorithms to study 4-axis motion control.As PMSM control is much more complex than the DC control,and the motor drive of market sell is not open, so it has some difficulties to study the properties of the servo system. In order to make better use of AC servo motors and deeply understand the principle of servo drives,in the paper, the constitutions and control ways of AC servo system are introduced.Basing on coordinate transform,the mathematic model of permanent magnet synchronous motor is established. The two control ways,vector control based on rotor magnetic field orientated and direct torque control based on stator magnetic field orientated, are studied and analysed Current-tracked PWM (iPWM)vector control and space voltage vector pulse width modulation (SVPWM) vector control are analysed theoretically in detail. Their simulation modeles based on matlab/simulink are completed, which validates the feasibility of control theory and provides the theory basis for threalization and debugging of real system.