Servo-Control System Based On DSP And The Research Of Positioning Problem

With the development of modern industrial and information technology, the AC servo system is widely applicated to the servo driver field with high precision and good performance. In the industrial application, servo-control system is required to satisfy the measures of performance as fast response speed, wide range of velocity modulation, high accurate positioning and running stably. Key technology is the design of servo-motor and drive equipment, detection unit, controller and optimization of control strategy.For the purpose of advance performance of the AC servo system, the excellence brushless DC motor is selected as the actuator, position servo system with full closed-loop is designed in the paper. The configuration and the basic work principle of brushless DC motor are analyzed, its mathematical model is established, transfer functions and characteristics are introduced first. Sensorless Back-EMF zero crossing detection are discussed., the method of LMS adaptive noise counteraction is putforward to detect commutating signals of BLDCM is presented which uses the voltage to detect the commutating position signals thus the moter work effectively in low rotate speed. Motor positioning problem is the focus of this research. Motor positioning problem is the focus of this research, Its fast, high-precision servo system, as well as stability are the key performance indicators. Several aspects are discussed. first for fast bake, Comparison and analysis through simulation, Selection of regenerative braking and reverse brake combination of ways to deal with the rapid braking, This was followed by the establishment of rapid response, accurate target tracking the location of all-digital closed-loop servo system. To drive the motor, based on TMS320LF DSP , use of the Hall current and position sensors, optical encoder signal acquisition to current location and speed of calculation. PID control is used on conventional method, but in some occasions, can't satisfy with the access control results. Combining the characteristics of the system, intelligent control algorithm is introduced, the current regulator Ring PI algorithm, the speed loop variable structure control with sliding mode algorithm. There will be real-time speed regulation and ensure no overshoot response in the dynamic-state and no error in the steady-state. Take into account the speed and accuracy, increase Position Control Central to complete the precision positioning , the system uses Fuzzy-PI combination of methods, the position error in the stage with Fuzzy algorithm regulation, enabling the system to the fastest reduce errors ,in the case of small deviations by PI algorithm allows the system speed decreases slowly to create conditions for accurate parking.In the theoretical analysis and simulation on the basis of the paper, the hardware and software of the control system are on research and designed. For the first part of the overall design, then the main circuit design including the selection of the main module components and parameters, software is modular in design, the process of software is discussed and all the major functional modules of the flow chart is mapped.Finally, do some experiments on real system platform, the experimental results are presented.