The Research Of Simulating The Railway Vehicle AC Traction System Based On CAN Bus

There are several changes for the electrical machinery velocity modulation's control policy in alternating current machine's developing process: voltage and frequency control; vector control; direct torque control.Although the voltage and frequency change control has basically solved the asynchronous machine smooth velocity modulation problem, it cannot adapt the higher request for the static property of velocity modulation system. The vector control can obtain the quick step response, but itself operation is vast and complex.The direct torque control obtained the widespread application in afterward period of time, because of its clear structure and excellent dynamic property. However as a result of the non-vanishing voltage vector's function, the electric motor has the torque pulsation when electrical machinery circumgyrating slowly, namely in the small torque windage situation. In following researching, many scholars make many improvements to the direct torque control. For example change the torque flux linkage from two-point regulator to three-point or fifth-order comparator, or change the dutyfactor of non-vanishing voltage vector in a control period. These methods are reducing the pulsation situation through cosummating invertor switch table to the refinement; it has made certain progress, but cannot solve the pulsation question completely.Afterward the scholar use the PI adjustment to substitute original sluggish control, simultaneously used the fuzzy control, obtained voltage space vector which is needed when the moment of torque agonic output under the different load running status. By this method, the size and the direction of voltage vector output are random; this method can track the torque and flux linkage's change rather than traditional DTC. However the PI controller has not been able to solve the contradiction that regarding between the static property and dynamic property, the setting value tracking and perturbation suppressing, the robust performance and control performance.This article improve the direct torque control with the integrated development environment Micro Message Bus(MMB) which is developed by the laboratory of mine voluntarily.It use the technology named"Transient Stability Overshoot"(Abbreviation TSO), turn a controller three parameter processes to the single parameter and multi-step process, obtained continuous mutative voltage space vector, it can solve the torque pulsation effectively. Finally takes this method as the asynchronous machine direct torque control system's control policy, obtained the very good effect in the electrical machinery's simulation running and the performance examination process.