| Nowadays, researches of matrix converter mainly concentrate to improve its modulation strategy and enhance the converter velocity of modulation system, such as the researches of inputting suppresses to avoid unbalance, reducing the loss of the switch, enhancing the stability of the system and applying the matrix converter to vector and direct torque control and so on. The correlative researches about how to improve the ratio of voltage transfer of Matrix Converter to more than 0.866 are less. Until now, the research of improving the voltage transfer ratio that domestic and foreign scholars pay attention to mainly concentrates in the strategy of controlling it, which result is when the ratio of voltage transfer is bigger than 0.866, the harmonic content of output voltage is increase.The article takes AC-DC-AC of Matrix Converter as a foundation, and pays attention to improve the ratio of voltage transfer of the Matrix converter, on the basis of which, the article proposes one kind of new electric power converter, that is Boost Matrix Converter. It introduces the Boost electric circuit to the electric circuit topology of matrix converter and takes use of its pressure-rise ability under high frequency pulse condition in order to achieve the goal of improving the ratio of voltage transmission of the matrix converter. On the basis of that, the article studies the different characteristic of the Boost direct chopping circuit and Matrix Converter and designed one kind of topology electric circuit structure of improved direct-current pressure-rise in order to guarantee the BoostMC has the merit of two-way energy to be possible transfer, therefore, the article has inferred the theory feasibility.According to the different applicable situations, the article starts from evolution of topology electric circuit and has studied many kinds of BoostMC Matrix converter and their characteristics about forms of topological electric circuit and them gave two kinds of inversion strategy that suited its movement way and introduced the inversion strategy of improving direct-current zero electric current trades flows with emphasis. With unifying the means of inversing the direct-current zero electric, the article proposes PWM commutate of specific power factor and the inversion control strategy of special complexes modulation.The article equivalently decomposes the BoostMC for three parts: commutate circuit, boosted circuit and inversion electric circuit and makes harmonic analysis. It decomposes the commutate side circuit changer functions Fourier into the low and high frequency component, and analyzes the connection between the high frequency component of circuit changer functions and the input current flow high frequency component of BoostMC. It may know that the input current flow high frequency harmonic component of BoostMC and the sample frequency of circuit changer be in reverse proportion. Therefore it is possible to improve the sample frequency of circuit changer to forbid the input current flow harmonic component.After obtaining the complete expression of boost electric circuit of induction current flow amplitude of N times, the analysis of harmonic component shows that first harmonic and harmonic component often change with the different capacity of C of side of output of boost electric circuit stabilivolt capacitance. The little value of capacitance is helpful to forbid the harmonic component. However, when we consider at the angle of stabling the output voltage, the situation is inversed. Therefore, the sampling span of C should be measure.One part of BoostMC output voltage overtone is own signal produces, another is caused by modulates. After improving the sampling frequency of circuit changer, we should mainly concentrates the output voltage harmonic components in the high frequency band and select the suitable low pass filter to filter the high frequency component of the output voltage. The article has established the BoostMC emulate model of MATLAB/SIMULINK, studied the technology of realizing main circuit and the numerical control system and manufactured the test platform of hardware of BoostMC of the circuit controller that take the DSP2812 controller as the control core. At the same time, the author has compiled the software procedure according to the modular principle with the C language, proposed the method of track and compensate of three-phase input voltage. Therefore, we can improve the controlling precise and realize the synchronized controls of rectification, pressure-rise and inverts three part of electric circuit.The result of simulation and the experiments indicate that in theory the BoostMC has the extremely high ratio of voltage transfer with the maintenance of original fine input and output performance foundation. In addition, although the Boost electric circuit is in the direct-current link, and has the stored energy part, the capacity is very small and not able to influence the overall system input power factor and we can make the factor of input power be 1 approximately through adjust the electric capacity inductance parameter. At the same time, because the inductance and the electric capacity we uses are small, it is impossible to influence volume and weight of system.The Boost circuit is not big to the overall system power input factor influence, moreover may cause the power input factor close, because simultaneously uses the inductance and the electric capacity are small, to influence really micro. The method proposed in article provided advantageous theory basis and conditions in the fields of electric drive, high voltage and high-amperage applications that Matrix Converter can be used.
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