High-frequency chain matrix type inverter topology with front stage being dual Buck-Boost inverters and modulation method thereof

Abstract

The invention relates to a high-frequency chain matrix type inverter topology with a front stage being dual Buck-Boost inverters and a modulation method thereof. A front-stage inverter topology is formed by sequentially connecting the dual Buck-Boost inverters, a high-frequency transformer T, a matrix converter and an LC filter. According to a front stage modulation method, a pulse width modulation (PWM) wave generated by a PWM signal generation link is processed, the buck-boost function is achieved by changing a duty ratio, so that the difference between working mode states of the two groups of Buck-Boost converters is 180 degrees, namely, one group works in a boost state, the other group works in a buck state, and positive square waves and negative square waves which are alternative can be obtained by subtracting the square waves output by the two groups, and the function of inversion is achieved; and according to a rear stage modulation method, logic processing is performed on the PWM wave generated by the PWM signal generation link and a sinusoidal pulse width modulation (SPWM) wave generated by an SPWM signal generation link, a high-frequency square wave output from the transformer is converted to a power frequency sine wave, and the front stage and the rear stage employ synchronous PWM signals to perform coordinated modulation. The high-frequency chain matrix type inverter topology has the advantages of simple modulation mode, relatively flexibility in control, wide application expandability and the like, and bidirectional energy flowing can be achieved.

Description

technical field [0001] The invention relates to the field of power electronic power converter topology and modulation, in particular to a circuit topology and modulation method using a double Buck-Boost circuit as the front stage of a high-frequency chain matrix inverter. Background technique [0002] An inverter is a topological device that converts DC power into AC power. The biggest difference between high-frequency chain inverter technology and conventional inverter technology is that it uses high-frequency transformers to realize energy transfer and electrical isolation between input and output, thereby reducing the volume and weight of transformers, reducing costs, improving power utilization, and improving energy efficiency. the working characteristics of the inverter. [0003] According to the circuit topology, the high frequency link inverter can usually be divided into DC / DC conversion type (DC-HFAC-DC-LFAC) and matrix conversion type (DC-HFAC-LFAC), among them, H...

AI Technical Summary

Problems solved by technology

In the application, the method of changing the turn ratio of the power frequency transformer at its output end is often used to achieve further boosting, but at the same time, the volume and weight of the power device are increased, which affects the popularization and use of this type of converter.

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