Hardware Design And Implementation Of PMSM Electro-hydraulic Servo System Based On XMC4500

Electro-hydraulic servo control system is a combination of electromechanical control system and hydraulic load system.It combines the advantages of two control systems,the system can greatly improve efficiency.Load of die-casting machine changes quickly,and electro-hydraulic servo system can meet the work requirements of die-casting machine.The main circuit of the system adopts classic AC-DC-AC topology,and power device is power integrated module(PIM).This paper proposes a novel interlock drive and protection circuit.The servo system has over current,over voltage,over temperature,under voltage lockout and other protection functions.Hardware over current protection circuit based on detection of IGBT saturation voltage drop has a quick response.The controller uses Infineon XMC4500 as the central processor.This paper builds the minimum system and peripheral processing circuitry.Peripheral circuits include five common communication circuits and three kinds of position detection interface circuit based on photoelectric,rotary and magnetic encoder.Off-chip EEPROM uses IIC communication to transmit data.An extra processor XMC1300 is used to deal with the process flow of industrial computer.XMC4500 and XMC1300 communicate with each other by RS485.The signal processing of the industrial computer and the servo control of PMSM are separated to ensure high response speed of servo system.Detection circuit includes DC bus voltage detection,output current detection,pressure detection of hydraulic system in die-casting machine,internal temperature detection of PIM module,position detection of motor rotor.Hardware design of electro-hydraulic servo system achieves four upgrade design.Interlock drive and protection circuit improves the safety of the system.Optimization of the blank time in over current protection circuit avoid the false over current fault alarm.It takes a variety of measures to prevent IGBT damage from the surge voltage during the process of IGBT switching.It solves the problem of Miller current triggering IGBT turning on during reverse recovery of inverse parallel diode.Snubber circuit is composed of CDE snubber capacitor.The purpose of using ACPL332 J and HCPL3120 optocoupler to design drive circuit is to improve the reliability and economy of the servo system and reduce the complexity of the system.The drive circuit can drive power devices up to 150 A.Modular designed power supply is not affected by the main circuit of power conversion module,the reliability of power supply is very high.