Control Study Based On Two-stage Matrix Converter Excitation Of Doubly-fed Machine

The double-fed machine not only can be used in variable speed system, but also can be used in variable speed constant frequency power generation system. And it can regulate the stator side's power factor. As the double-fed machine control system's excellent performance, it has a extensive application prospect in the field of industrial drives and power generation. Two-stage matrix converter as a new'green'inverter, has the following excellent characteristics:Bi-directional power flow, controllable input power factor, sinusoidal input-output current, simply and reliable commutation etc. A two-stage matrix converter excited doubly-fed machine control system is investigated in this paper.Firstly, according to the basic principle of rotating machine, analyze the operation principle of the double-fed machine, and the energy conversion relationship when the Doubly-fed machine work in the different conditions. By the coordinate transformation, we present the Doubly-fed machine's mathematical model on the synchronous coordinate.Secondly this thesis introduces the basic operational theorem of the two-stage matrix converter, and the modulation strategy. Through MATLAB simulation verify the feasibility of the modulation algorithm.Then according to the vector control theory, stator flux oriented and stator voltage oriented vector control model of the double-fed machine is established. The two-stage matrix converter is applied in vector control system as an excitation power. And a simulation model of the system is built. Through analyzing double-fed machine on different operating conditions, verify the feasibility and correctness of the design system.Finally this thesis design the hardware structure of the two-stage matrix converter excited doubly-fed machine stator flux oriented vector control system, and some of the software design.