Research On Multi-motor Synchronous Controller Based On DSP

As the social industrialization developed rapidly, in many areas of production, only by a single motor operation mode has been unable to meet the product of the production requirements, this needs good coordination control between multiple motors to complete. Therefore,motor synchronous control is a significant research direction with high application value.The article introduces the research background of multi-motor synchronous control, for the high performance of PMSM in the field of good-performance AC servo with good qualities: higher power density,faster response, larger output torque etc, this article selects them as the main control objects. Aiming at the major problems of the multi-motor synchronous control: 1, The synchronization algorithm is too complex, if disturbed, the speed will appear different degree of change, synchronous effect is poor. 2, There is a large deviation between the actual speed and given speed when the motor runs. 3, The structure design of control system is unreasonable, some key parts of the system are so complicated that make the bad power factor and poor stability; the other parts are too simplified to do precise control of motor, and are not suitable for high precision servo control. According to the above problem, this article studys from the aspects of the control strategies and system design.Control strategies: firstly introduce the structure of the permanent magnet synchronous motor and classification in detail, and then analyze common coordinate conversion and its corresponding mathematical model, for the selection of control strategy providing theory basis. In this article, the control of single motor selects FOC-SVPWM strategy, and then adopt the way of simulation to verify it, the simulation results show that by this strategy speed is controlled accurately with a strong ability to resist disturbance, and the performance of system dynamic and staticresponse is good. Then start synchronous control research, comparing and analysising of the advantages and disadvantages of different synchronous strategies, the deviation coupling synchronous strategy have a great advantage than other synchronous strategies, then improve the deviation coupling synchronous strategy: on the one hand expanding the number of the control motor, on the other hand using fuzzy PID algorithm in its front speed compensation part. Finally, make it compared with master-slave synchronous control in simulation, the results indicate that the speed of four motors controlled by the former strategy response quickly and effect of synchronous is good when disturbed; While the speed of four motors controlled by the latter strategy appeare different degree of delay and imbalance phenomenon. Finally, focus on the research and analysis of the synchronous effect of deviation coupling strategy under normal conditions, load disturbance and speed mutation.System design: according to the defects existing in the traditional analog controller, this article adopts the digital controller based on DSP,mainly study the key circuits in the system: As a key part of the whole system, motor power drive circuit uses smart power integrated circuit to replace the traditional discrete circuit component design, including the selection of power device parameters and interference isolation measures;Using single chip microcomputer auxiliary control circuit to assist the DSP processor to control the system and provide digital display function.Finally finish the design of whole system: the detailed design of the main circuits and system programs. Studying single motor control experiment in detail, the results show that when faced with the load disturbance, the speed fluctuation is small, response time is short and the motor runs stably. Then using CAN bus and RS-232 communication mode to build the multi-motor synchronous control experiments, the results show that each motor is running smoothly and the synchronous effect is good,verify the feasibility of this topic.