The Research Of Multilevel Matrix Converter Based On Space Vector Modulation

On the basis of the conventional matrix converter and the multilevel inverter, a novel multilevel matrix converter as a kind of power electronics is proposed. The multilevel matrix converter can operate with multilevel switching, so the output voltage waveform is closer to the sine wave with minimized harmonic contents. It has symmetric circuit, input side and output side can be reversed, so it is capable of both increasing and decreasing the voltage magnitude, and can break through the restriction that the voltage transfer ratio of conventional matrix converter is less than 0.866. As a word, the multilevel matrix converter is an ideal power converter, which would attract significant attention and be challenge in the field of transform electric energy device and new energy sources.Regarding the topic"the multilevel matrix converter"as the main subject, this paper has studied the topology of the circuit and the basic principle, expounded the strategy operating with two-level switching. The space vector modulation strategy that the multilevel matrix converter operates with three-level switching is developed in a creative way, and the simulation results validate the feasibility of the strategy. The mathematical model and state space model of the multilevel matrix converter system are founded. On the basis of them, the system stability, controllability and observability are analyzed. These are useful for researching the multilevel matrix converter. In detail, the main content of this paper is as follows:In comparison with conventional matrix converter topology, using the basic unit thought of multilevel converter, this paper introduces the generating of multilevel matrix converter topology circuit, and analyzes the states of the H-bridge switch cell and the principle of branch operating.Mathematical model of multilevel matrix converter system has been set up, furthermore its state space model is educed. The system stability is judged by Lyapunov's method, as well as numerical method, and controllability and observability are analyzed with the numerical method.Based on space vector modulation, how to generate the elementary space vectors is depicted. There, the modulation strategy operating with two-level switching is expatiated and the modulation strategy operating three-level switching is developed. Then, simulation model is built using MATLAB/Simulink, and the results test the feasibility and effectiveness of control algorithms.