Design And Research Of DC Servo Driver Based On DSP And EPA Technology

With the fast development of computer technology and micro-processor, servo system tends to be full digital controlled, and the related technologies have become more and more perfect. But currently, in our country, the research on DC servo driver is not so mature, imported products have always been the first choice for many applications. Taking the control of robot integration of joint as its background, this paper discussed the design and research of DC servo driver based on DSP and EPA technology.In the design of hardware, TMS320F2808, which is specially developed for motor control, was used as the core processor, and six MOSFET power tube were combined to be bridge circuit, which supply the driving power. There are three characteristics of this design:the first one is low voltage input but high power output; the second is that it can not only drive the brush motor but also the brushless motor, so it can be used in more field; and the last one is that it can communicate with PC through EPA which has high transfer rate and good certainty.In the design of software, Interrupts are emphasized. Main program takes responsibility of initialization and configuration of interrupt vectors. CANopen interrupt and EPA interrupt are used for data transaction between PC and DC servo driver. PWM interrupt is taken for execution of control algorithm under several control modes and regulation of duty circle. Above all, the transplantation of CANopen protocol on DSP is key point of design in software, including modeling of device, configuration and access of object dictionary.Finally, control algorithm is much more deeply discussed in this paper. The parameter regulation in traditional PID control has always been done by engineers according to their experience, which is time-wasting and full of uncertainty. So an improved single neuron PID control strategy was presented, which adopts nonlinear algorithm for proportional constant. By using this improved strategy on speed regulation of brushless DC motor, the experiments prove that it can not only speed up the convergence rate, but also effectively settle the instability caused by the load disturbance comparing with traditional PID controller and original single neuron PID controller. Particularly, the robustness and quality of this improved controller are well verified on condition of large load.