Research And Realization Of Coordinated Control For Multi-motor Drive System

Coorperated control of multi-motor drive system has always been one of the important topics in the field of motion control. It is widely applied in automatic control of wire-drawing, textiles, printing and dyeing, paper making, steel rolling and other manufactures and production processes. Thereforce, it has a great significance to study the coordinated control of multi-motor drive system.Firstly, this thesis analyzes the multi-motor drive system in detail, which can be divided into multiple DC motor drive system and multiple AC motor drive system for further research. Then, three kinds of operational relationships of motor drive units, namely front and rear relationship, proportional relationship and unrelated relationship, are analyzed. By analyzing the control strategy of different operational relationships of the multi-motor drive systems, research focus puts on the coordinated control strategy of the multiple DC motor drive system and multiple AC motor drive system which run by a certain percentage.In order to develop a good coordinated control strategy for the multi-motor drive system, characteristics of uncross-coupling coordinated control strategy and cross-coupling coordinated control strategy are analyzed in this thesis. Based on the two basic coordinated control strategies, a synthetical coordinated control strategy structure which combines the advantages of the two basic strategies and has a better performance is proposed. As the multi-motor drive system has the complex characteristics of non-linear, strong coupling and uncertainty, the fuzzy control is applied to the coordinated control strategy for error compensation. Thus, a coordinated control strategy for multi-motor drive system which uses the fuzzy control to compensate the error is obtained.In order to verify the actual performance of the proposed coordinated control strategy of multi-motor drive system, this thesis establishes a multiple AC motor drive system which is composed of four simplified models of vector control of the AC asynchronous motor. The proposed coordinated control strategy is programmed in Matlab. The simulation results verify that the proposed coordinated control strategy has good coordinated properties when it is used in the multiple AC motor drive system. Meanwhile, design a small car system which is driven by four DC motors by the DSP, and apply the proposed control strategy to the system. Then, according to the actual running effect of the car to further validate the proposed coordinated control strategy also has good coordinated properties when it is used in the multiple DC motor drive system.Results of the simulation experiment and the system operation verify the effectiveness of the coordinated control research for multi-motor drive system.