Study Of Matrix Converter Based On DSP And CPLD

The matrix converter is an array of controlled semiconductor switches that connects directly the three-phase source to the three-phase load. It is considered as an "total silicon" power converter with advanced circuit topology.MC permits frequency conversion in a single-stage processing without large reactive energy storage components. It draws sinusoidal input currents and allows the input fundamental displacement factor to be set at unity or freely varied regardless of the load power factor. Besides these, it is capable of performing frequency conversion with sinusoidal output voltages and currents at the desired output frequency and allows bi-directional power flow. It has advantages on saving energy and protecting environment.All of the attractive features have been investigated in the last two decades. In the last few years, an increase in research work has been observed, bringing this topology closer to the industrial application.This thesis discusses principal issues of the matrix converter such as prime principle, control strategy, current commutation etc. Some valuable experiences and conclusions are given, which found the basis of the project for the further studies.Firstly this paper presents several research focuses about the matrix converter, and then the basic principles of MC will be discussed. There are many modulation algorithms for MC, and one of them-the indirect space vector PWM(SVPWM)-is used in this paper. The indirect SVPWM is deeply investigated in this paper, and the function is also given. A simple simulation modal of MC based on MALAB was implemented to test the method. In the simulation, a speed control system is also driven by the MC.Reliable current communication between the three-phase source is very important. The structure of bi-directional switches for MC are analyzed. Reliability and accuracy of four-step commutation strategy is proved. The strategy is accomplished by CPLD.In the end, this paper develops an experiment system to verify the algorithm effectiveness. The system design about the hardware and software of MC is given. The control system is composed by DSP and CPLD. The algorithm is implemented in DSP, and the calculation results are transported to CPLD. The CPLD achieved the reliable current commutation. The final experiment results verified the algorithm.