Research Of Stepping Motor Vector Control Based On FPGA

In recent years,Chinese aerospace technology has developed rapidly.Due to its low cost,simple control mode,high control accuracy,stepping motor is widely used in the field of aerospace.However,with the development of modern science and technology,especially the development of modern control theory and the emergence of high-performance controllers,higher requirements are put forward for the stepper motor control system.The traditional stepping motor control system adopts the open-loop constant current control mode,which has some problems such as large step angle,large current and high energy consumption.Meanwhile,the traditional controller has poor real-time performance and can not meet the requirements of high-precision control.FPGA has the advantages of simple programming,rich I/O resources,fast calculation speed and so on.This design uses FPGA as the main control chip,to achieve closed-loop control of two-phase hybrid stepping motor.To provide a reference to solve these problems,a new method based on vector control technology and classical PID control theory,precise control of the stepper motor winding current is adopted.First of all,a mathematical model of stepping motor is constructed.By using vector control technology,the current of stepping motor A and B phase are decomposed into the rotating coordinate system,and the decoupling of current vector and the estimation of torque to current are completed.The current conditions that can be applied to the control system,give the final program of stepper motor closed-loop control system.Secondly,taking FPGA as the master chip,analyzing the functional requirements of the system,the hardware design of the stepper motor drive control system is completed and the detailed circuit schematics is provided,in the principle of simplifying the hardware system and reducing the cost as much as possible.Then,closed-loop control functions are all realized by FPGA software system.The overall design of FPGA software system is given,and the mutual coordination relationship among the various functional modules in the software system is clarified.Give full play to the characteristics of FPGA parallel computing,to achieve the optimization of software systems.In the premise of meeting the timing requirements,shorten the closed-loop control cycle and reduce FPGA resource consumption.Finally,the model of stepper motor and control system is built in Simulink,the vector control algorithm of the stepper motor and the closed-loop control system are simulated to verify the correctness of the algorithm and the performance of the closed-loop system.The experiment platform of upper computer,lower computer control system and stepping motor is set up,and the performance of closed-loop control system is tested comprehensively.Simulation and experimental results show that the system shows good running performance,realizes the speed control and position control function of the stepper motor,reduces the power consumption at the same time,and has great practical value.