Research And Implementation On New Servo Control System Based On Multi-channel Iterative Structure

Precision is one of important index of the quality of servo system and how to improve the accuracy of servo control system is always a hot topic in the research of the theory and control engineering. In the present servo control strategy, the method of solving the problem is better and the general method is based on the compound control of the feedforward and the feedback mode. But the way realized high precision which the system can interfere and can be measured and the target system model can be concluded. Because of the limitation of the stability of the feedback system, the high precision and broadband of the system are hard to meet both of the two contradictions. Therefore, in order to improve the servo system accuracy and the system bandwidth, this paper presents a servo control method based on multi- channel iterative structure, Here is the research:(1)A servo control principle and algorithm based on multi-channel iterative structure is presented. Based on the idea of system deviation sum of the polynomial iteration approximation alternative, let polynomial in the number of iterative channel structure in each channel corresponds, systematic deviations in multiple channel compensation, ultimately enable iterative output value strictly approximation system to quantitative, realize high precision servo tracking;(2)Make comparative analysis and advantage assessment on forward-feedback control strategy and multi-channel iteration structure control strategy on A comparison of current servo tracking control strategy and control based on multi-channel iteration in Simulink simulation platform. For the same system model, we use the feedforward and feedback, double channel, three channel iterative structure method respectively to the step signal, sine signal do tracking simulation study and evaluate the effectiveness of multi channel iterative algorithm structure and comparative advantage. At the same time, the anti-interference ability of the servo system and the bandwidth of the system are analyzed;(3)The combination of DSP+FPGA and upper computer servo control system is designed in the paper which the DSP system has proposing servo control algorithm, receives the control instructions from the upper computer and then analyzes the instructions; The FPGA system analyzes the reference voltage that was given after the DSP system processes and treat it logically to emerge the PWM wave relatively, then control the electric motor after the area of the power driver. The upper computer system achieves the input of characteristic parameter, the output of the operation procedures and the delivery of the control order;Experimental results show that the servo control algorithm based on multi- channel iterative structure has the advantages of simple engineering implementation, large input bandwidth and high tracking accuracy compared with the traditional algorithm. Meanwhile, the DSP+FPGA+ upper computer can satisfy the design objective which has the perfect hardware function, high real-time, strong expansion capability and higher tracking precision.