Research On Servo Motor Torque Test System Based On Load Simulator

Load simulator is used to simulate acctual working condition of motor in a lab environment.It is widely used in servo motor performance testing system,providing simulation load torque for motor to be tested.The eletrodynamic load simulator is a passive torque loading system,surplus torque caused by the motor active movement was an important factor that restricts the loading accuracy and the loading bandwidth.In order to enhance the load simulator,this paper improved from the aspects of system design and control strategy.In view of the limited operational capability of embedded system,while the high requirement of loading precision and real time for load simulator,put forward the hardware in the loop scheme for torque loading.This paper established servo prototype system based on the X86 lower computer,while RIO card board carrying FPGA module run servo driver current loop,and automatic test board relized power conversion and feedback signal cnonditioning.The signal of torque sensor was connected in card board by FPGA port,forming torque closed-loop control and promoting control precision.Based on the analysis of load torque and load inertia characteristics in synchronous belt movement,raised dynamical model for synchronous belt in Adams environment,and obtained load torque curve.Simulink model of eletrodynamic load simulator was established on basis of permanent magnet synchronous motor model,dynamic simulation model and load simulator model.According to the characteristics of the torque load signal of the simulated synchronous belt,repetitive control strategy was proposed.In order to improve the system response speed,a hybrid controller combining PI control and repetitive control was designed.Combining the advantages of repetitive control without dead time tracking signal and the real-time responsiveness of PI controller,the high performance tracking of load simulator was realized.Simulation and physical experiment of load simulator verified the supression performance of the loading system based on the composite controller.Finally,designed experiments comparing synchronous belt load with simulated synchronous load,and verified the prformance of the load simulation test system.