Research On Motor Controller For Two-phase Hybrid Stepping Motor Based On DSP

Stepper motors have the advantages of high precision, no accumulated position error, small drive current, low power consumption, high efficiency, brushless etc, and are widely used in all fields. The main products of current market for stepper motors are two-phase hybrid stepping motors. This paper introduces a kind of digital control system of hybrid stepper motors based on two-phase DSP. The system uses TMS320F28035 microcontroller as the core control device, and the lower bridge arm resistance sampling and hybrid encoder, combined with the current, speed feedback circuit and coordinate transformation to realize the digital control of two-phase hybrid stepping motors.In the aspect of control strategy, this paper introduces two kinds of motor control-strategies of stepping motor subdivision control and stepper motor torque vector control, through the analysis of the mathematical model of two-phase hybrid stepper motor, and uses MATLAB toolbox of SIMULINK to carry out simulation of the subdivision control and torque vector control strategy. This paper applys the theory maximum torque-current ratio to the vector control of two-phase hybrid stepping motor through the deep research on the mathematical model of stepping motor, designs the corresponding strategy of two-phase SVPWM for two-phase inverter, and designs the strategy of current sampling depended on the lower bridge arm resistance and current reconstruction. The simulation results show that, the SVPWM control strategy, current reconstruction strategy and two kinds of control mode is feasible. Finally, in order to verify the results of simulation, develops the hardware system of two phase hybrid stepping motor digital driver, using the DSP chip TMS320F28035, which is developed for motor control, as the core controller, and designs the relevant software system, and the experimental results show the feasibility of the system.