Speed Control of DC Servo Motors with Programmable Analog Devices

Speed Control of DC Servo Motors with Programmable Analog Devices

DC servo motor has the characteristics of fast response, good stability at low speed and wide speed range. It is often used in the follow-up system for precise speed control and position control. It is widely used in industrial, national defense and civil applications. It is in the artillery stabilization system, shipboard platform, radar antenna, robot control and other occasions. Although the development of AC servo motors is quite rapid, it is difficult to replace DC servo motors in these fields.

The traditional DC speed control system consists of two feedback loops, namely the speed loop and the current loop. The speed control is controlled by a speed measuring machine, a current sensor (Hall device) and an analog electronic circuit. Modern digital DC servo control uses a high-speed digital signal processor (DSP) to directly sample the speed and current signals, and implement various functions such as digital comparison, digital adjustment operation (digital filtering), digital pulse width modulation, etc. through software. Precise control of speed. Compared with the two, the analog speed control system has a simple structure, low cost and high reliability, but the debugging is more complicated, because the modification of the circuit parameters often requires hardware changes; and the digital speed control system has a complicated structure and high cost, but the adjustment The speed is very high and the debugging process is also easy. The performance of the speed control system can be controlled by software.

This paper introduces a method between the analog speed regulation and the digital speed regulation, that is, the programmable speed control system (ispPAC10) is used to realize the analog speed control system. The circuit parameters of the system can be adjusted by software and can be established. The system model is simulated. This method is used to improve the automatic zoom system of a CCD camera of the original DC governor, and has achieved good results.