Based On The Design And Implementation Of Direct Torque Control Of The Single Inverter Multi-machine Drive System

With decades of development, the AC Drive system has taken the domain position of DC Drive system in many field of social application. But in some specific working condition, which would rise unique requirement such as large inertia or high power, the traditional single inverter-single motor control strategy can no longer meet the demands. Nowadays, the novel integration of single inverter-multi motor system and vector control in rail transport field has been proved to be an potential implication with high running performance, low costs, energy saving and high reliability.Referenced with existing theory, this paper has raised a new single inverter-multi motor system based on direct torque control. The innovation of system is that:when dealing with different type motors or motors in different working condition, it abstract an virtual motor that its stator current, stator flux and torque correspondingly equal to the average value of all working motor. Exerting the direct torque control on this virtual motor minimizes the relative deviation between motors and a certain operation tendency is realized for all the motors.On the base of theoretical derivation, this paper has developed comparison experiment between direct torque control and vector control for the same single inverter-multi motor system. The results from Psim simulation platform and PE-VIEW9 hardware platform have spontaneously shown that both control performances are comparable, which is also a proof for feasibility of the proposed system.