Research On Induction Motor Vector Control System Adapting Multi-Bus Communication Mode

With the development of industry technology, the requirement of operation performance and long-distance control performance is improved greatly. Because of its good performance, the induction motor variable frequency drive system is applied widely in industrial control field. To make induction motor have better performance, the vector control system which uses rotor flux adaptive observer and the network control technology which contains many fieldbus protocols are deeply researched in this paper. The induction motor can have good operation performance in many fieldbus.Firstly, the induction motor mathematical model is provided in the three-phase static coordinate and two-phase rotating coordinate. Analyzing the vector control base on rotor flux orientation, this paper designs the double closed-loop system with the flux and torque as the inner-loop and the speed as the outer-loop, eliminating the coupling between torque and flux.Secondly, based on analyzing the tradition ways of rotor flux observer, this paper uses model reference adaptive system to observe rotor flux. In the rotor coordinate, this paper establishes the rotor flux observer, then proves the system stability and the parameters convergent by Lyapunov stabilization theoryПBased on the theoretical analysis, the simulation researches on the steady-state performance and dynamic characteristics of the induction motor vector control.Thirdly, the networked control system is introduced into induction motor variable frequency drive system. By the designing of a protocol converter which realizes the conversion from RS485, MODBUS and CAN fieldbus to RS232, induction motor can separately work in the three fieldbus.Finally, Using the TMS320F2812 digital signal process as the control unit, the experiment system is achieved. The experimental results prove the correctness and practicability of the induction motor vector control system designed based on multi-bus protocols.