Research On The High Power AC Servo Control Of Electromechanical Actuator And The Communication System

Currently, a rapid progress has been made in the area of the small power missile electromechanical actuator. But in contrast, there are many problems with the research on the high power missile electromechanical actuator. The critical technology of the electromechanical actuator, especially the research on the PMSM(permanent- magnet synchronous motor) and its control method and the application of the electromechanical actuator on the large ballistic missile is less. The networked research of the servo drive system is not mature. To cure the above problems, this paper designed the PMSM for the high power missile actuator, developed the hardware circuit for the controller and studied the communication technology based on the protocol.Firstly, according to the miniaturization, high power density and other technical requirements of the missile actuator, this paper designed the PMSM for the high power missile actuator. The rotor of the PMSM was selected and optimized reasonably. The slots and poles number of the PMSM was determined. The material of the motor, especially the permanent magnet on the rotor was selected deliberately. Besides, The electromagnetic simulation analysis was carried out on the motor model using the JMAG software. The data such as torque ripple, flux density, iron loss and copper loss, were obtained from the simulation to improve the PMSM.In addition, the controller used to drive the high power servo system was designed particularly. In the aspect of hardware circuit of the controller, the power drive part, the current feedback part, the angular position information feedback part, the bus voltage signal detection and the temperature signal detection part were designed. Furthermore, to increase the system’s anti-jamming and security, the anti-jamming measures was carried in the bus input. Some protection measures were made in order to avoid the excessive impact on electrical power.Thirdly, in order to realize the control of the motor, based on the PID control method, this paper adopted three closed loop control strategy which include current loop, speed loop and position loop. Besides, the flux-weaking control method was introduced to optimize the control effect. In order to achieve the communication between the four chips and control the motor through Twin CAT, the hardware of the communication system based on the Ether CAT was optimized and the communication sequence and program was designed. Some experiments were did to verify the effect of the communication.Finally, the experiment platform was made to test the whole system. On the one hand, the basic properties of the hardware system such as motor counter electromotive force coefficient, coefficient and the delay of the power switch device IGBT switch were tested. On the basis of the normal system, the control parameters of the current loop and speed loop adjusted to make sure the system works with the optimal state based on the PID control method. In order to meet the high torque and high power requirements of the electromechanical actuator, the loading experiment was did to test the actual output torque and power of the motor. On the other hand, the program using to achieve the tracking property of the electromechanical actuator was did.