Research On Dual-loop Control System Of Coreless DC Servo Electrical-mechanical Converter Based On DSP

Electrical-mechanical conversion module has been a bridge connected electrical components and mechanical components, which is the key to digital valve research, the improvement of their performance is a premise to improve the performance of a digital valve. As a digital servo motor actuator, its performance has a direct impact on the digital valve. In order to solve the problem when traditional stepper motor worked in a larger loading environment (including inertia loading and the spring force), speed response has been limited, replace the stepper motor with the servo motors of better performance.The dual-loop servo control method has been designed for the Coreless DC motors, the research on the control system and the mathematical model of control object, the software implementation of control strategies, the hardware design of controller based on TMS320LF2812(DSP).This design solve the earlier stage technical problem that Coreless DC servo motor control system applied to digital valve as a Electrical-mechanical conversion module.Research contents are as follows:1. With the unique characteristics of the Coreless DC servo motor, it has non-core structure, measured the resistance of the prototype motor, the torque coefficient, and other parameters constant. Based on the given voltage-torque relationship and torque-speed relationship of the prototype motor, established mathematical model of the DC motor, analyzed its steady-state and dynamic response characteristics, and make simulation in MATLAB.2. Describing the principles of the current/location double closed loop servo system and its main component aspects, has given the dynamical block diagram and transfer function of the control system, and make simulation in MATLAB.Add correction part in the current loop, study the characteristics of their compensation, and contrast compensation results in the experiment. It is proved this part can improve the tracking performance of the current loop.3. The software and hardware design and the implementation of the DC servo controller, the generation of the sinusoidal control signal, dual-loop control, the presentation of classic three algorithms have been introduced and hardware circuit blocks,DSP control module and software control strategies also been described.4. A DSP-based experimental research platform has been built to get the dynamic performance of closed-loop control system in experiments, to analyze the system’s step response curves. Position tracking control experiments validate the theory and design method of the location closed-loop DC motor servo system, the results is consistent with simulation. It shows that the double-loop control strategy is effective.5. The article summarizes the main research works and results, proposing research work and the direction of the prospect.