The Design Of Multi Linear Switched Reluctance Motor Control System Based On ?C/OS-? And Dual DSP

Linear Switched Reluctance Motor(LSRM)is a direct-drive linear motor,with the advantages of simple and strong structure and high reliability.In this paper,a coordinated control system based on three LSRMs have been developed.The system applies a classic control system structure,including the controlled objects,feedback link,drive link,control link and other essential components.Firstly,the mechanical structure,electromagnetic characteristics and operation principle of LSRM are analyzed.In this paper,the control diagram is presented and its mathematical model is deduced.The static and dynamic electromagnetic characteristics of the motor are analyzed by finite element analysis software——Ansoft.It is important to analyze the commutation motion process of LSRM and the mathematical relationship between the electromagnetic force and current accurately,which is the starting point to design this control system and also the basis of the design of the control and drive links.The feedback link employs the RENISHAW linear displacement encoder and the encoder has a magnetic scale with the resolution of 250 lines.A conversion circuit transfers the output differential signal from encoder into single-ended signal which flows into controller,forming a single closed-loop feedback structure.The minimum clock frequency of pulse counter is 20 MHz.The drive link uses nine Copley drivers and three drives the three-phase windings of a single motor.The driver uses 48 V,500 W direct current(DC)power supply,and its characteristics of input and output mainly represent in the mathematical relationship between the input variable duty cycle of PWM signal and the output current level.This paper applies the software CME2 to carry out driver parameter debugging to meet the requirements of response speed and accuracy.The control link employs two TI F28335 digital signal processor(DSP)development boards,and peripheral resources QEP,PWM,CAN,SCI,GPIO are included.Program is developed and debugged in the integrated development environment CCStudio3.3,and the program design process has introduced Embedded real-time operating kernel ?C/OS-?.This paper introduces the operating principle of ?C/OS-? and transplant it into F28335 DSP board.On this basis,it realizes the development of system control program and communication program.In the personal computer(PC),C# windows platform is applied to develop interface software to monitor and control the system.Then the designed control system is tested and three motors can translate according to the command signals.In this paper,the real-time position error curves of three motors are provided,and it can be seen that the tracking accuracy and synchronization precision are both ±0.4 mm,which achieves the expected control target.Finally,the paper makes a summary of the work,and a further look is made from the control system structure,DSP software optimization and PC monitoring software functions in three aspects of the work.