Research On Switched Reluctance Motor Speed Control System Based On AVR Control

Switched Reluctance Motor Drive System(SRD)is a new type of AC speed control system.Because of its simple structure and excellent electrical properties,it has been widely used in many fields.It has become one of the hot topics in the field of electrical drive.At present,a lot of switched reluctance motor speed control system is based on Digital Signal Processing(DSP)as the core control chip.In comparison,the overall performance of DSP is better than MCU.But the cost of DSP is greater than the cost of MCU.In addition,some of the conditions are relatively poor,the anti interference of DSP is weaker than the single chip.DSP requires complex external anti interference circuit,and the cost will increase.Under some conditions,the switched reluctance motor speed control system based on MCU can be used as a scheme to replace the switched reluctance motor speed control system based on DSP.This paper takes the engineering realization as the goal,takes the AVR monolithic integrated circuit as the core control chip,takes the analog circuit to participate in the analog digital mixed circuit to control the switched reluctance motor speed control system.The switched reluctance drive system of 22 kW three-phase 12/8 is studied and designed.Firstly,the working principle of switched reluctance motor is st udied.The linear mathematical model is used to analyze the torque and current of the motor.we study the control strategy and the process of starting and braking about the motor.Finally,the speed current double closed loop speed regulation system is con structed by using PWM control.Then,the hardware design and software design are carried out.hardware design include power circuit design and control circuit design.The part of power circuit studies include the rectifier circuit,the inverter circuit,the power semiconductor switch device's choice as well as the corresponding drive circuit design.In the control circuit part,because the circuit is relatively complex,so the circuit module decomposition,with a large number of circuit diagram to introduc e the design.Including: MCU minimum system,position sensor circuit,position signal channel,current detection circuit,speed current analog control circuit,logic signal processing circuit,current protection circuit and communication circuit.The speed current analog control circuit is the core of this paper.Compared with DSP,MCU has a slow speed,which is used to control the real-time performance.So the analog circuit is used to participate in the control to increase speed.Since there is a speed current analog control circuit design,so the complexity of the software is much simpler.Mainly based procedures,speed calculation procedures and the need to use the interrupt program.Finally,the test platform is set up to test the working current,torque output,power output and system efficiency.Under the conditions of low speed and high speed,in line with the theory and design expectations.The problem of noise interference is analyzed and the method of filtering noise is put forward.It provides direction for further optimization design.