Research And Implementation Of The Vector Control System For Induction Motor

Induction motor is an non-linear,multivaribale,high -order and close coupling System. It's torque is not controlled as the DC motor. With the appearance of the new power electron apparatus and microprocessor and the development of the control theory on Alternating current (AC) motor, the technology of variable frequency speed variation has improved rapidly. AC motor can be controlled according to DC motor control rules by vectory controlling which is one of the strategies for AC motro drive with high performance.Vector control is developed based on the idea that the controlling means of induction motor can be equivalent to the DC motor, The induction motor mathematic model that is high nonlinear and complex coupling can be separated by coordinate transformation theory, Stator current can be decomposed into excitation current component and the torque current component, Then the magnetic field and torque can be separately controlled by controlling the two current components like separately excited DC motor.This paper designs a hardware platform of vector control system based on the high performance DSP (TMS320F2812) and and unifies uses American Xilinx Corporation's CPLD chip. Finished the designing and debugging of the hardware system. The hardware's structure is clear by using modularization designing. In this paper, the protection circuit has done a study on the over-current, overvoltage, undervoltage, missing phase do hardware design, to improve the system response to the accident rate, and real-time security protection system as a whole.While realizing the digitization hardware system, programming the real-time control software system, and drawing the flow chat of vector control software system on DSP. The software system uses the sequence and it can be interrupted by a sub-routine at any moment. The programming uses a mixed method of C and Assembly so that it is can work effective. But the programming in CPLD chip with the hardware language verilog HDL, writing the double-loop softsystem of the current loop and speed loop.Finally does some routine experiments on the hardware and the whole system tu confirms the designing plan feasibility, the debugging result shows that double-loop control system running reliably, at low-speed running stability, and positive inversion responsive to verify based on the rotor field-oriented the proper control strategy and based on TMS320F2812 and CPLD hardware circuit reliability.