A hybrid control method for dual active bridge converters based on asymmetric modulation

Abstract

The invention provides a hybrid control method for dual active bridge converters based on asymmetric modulation, which belongs to the technical field of converter control methods. This control method proposes a new asymmetric phase-shift modulation, which is externally phase-shifted by D 1 and switch forward duty cycle D 3 Two quantities are used as control variables, and on the basis of this modulation method, by selecting four different control rates under different load conditions, and then adopting different control schemes, the soft switching in the full power range is realized, and the reduction is significantly reduced. The return power and current stress are reduced, and the power transfer efficiency is greatly improved under light load conditions.

Description

technical field [0001] The invention belongs to the technical field of converter control methods, and in particular relates to a hybrid control method for dual active bridge converters based on asymmetric modulation. Background technique [0002] The proposal and research of Dual-Active-Bridge Converter (DAB) aims to improve the power density and efficiency of traditional converters. It has many excellent properties: there is no excessive additional reactive power. Components, power flow can flow in both directions, power density and efficiency are high, operating frequency can also be high, input and output isolation, easy to achieve soft switching and so on. Therefore, DAB converters are often used in high-power applications such as high-voltage power distribution systems and electric vehicle charging. [0003] There have been many studies on the control strategy of DAB. The most traditional control method is Single Phase Shift (SPS). In this method, the duty cycle of the...

AI Technical Summary

Problems solved by technology

Current stress refers to the maximum current value that electronic devices need to withstand when they work normally. The larger the current, the greater the turn-on and turn-off losses of the switch tube, and the greater the power consumed by parasitic parameters such as parasitic resistance of the circuit. , so under the same power condition, the greater the current stress, the higher the loss and the lower the efficiency

The return power is also an important component that affects the efficiency. The return power can also be called reactive power, which is the negative power caused by the opposite polarity of the voltage and current of the inductor in a switching cycle. This part of the negative power needs to consume the positive power. To offset, resulting in increased circulating power and current stress, increased loss of power components and magnetic components, resulting in reduced efficiency

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