Decoupling control method and device for input-series and output-parallel DAB converters

Abstract

The invention discloses a decoupling control method and device for input-series and output-parallel DAB converters. The inputs of N identical DAB converters are connected in series and the outputs areconnected in parallel, and a first phase shifting ratio Di and a second phase shifting ratio De are obtained through input voltage sharing control and output voltage control respectively; the controlsequence between switch tube drive impulse sequences is obtained through phase shifting control according to the first phase shifting ratio Di and the second phase shifting ratio De; and switch control signals with a control sequence are input to the control ends of switching devices Q1-Q4 on a primary side H1 of a transformer of each DAB converter and to the control ends of switching devices Q5-Q8 on a secondary side H2 of the transformer of each DAB converter, in order to complete the control process. According to the decoupling control method for input-series and output-parallel DAB converters provided by the invention, the input voltage sharing and the output voltage are kept constant by using the two phase shifting control degrees of freedom of double phase shifting control of DAB converters. Compared with the traditional single phase shifting control, by increasing the number of control degrees of freedom, complete decoupling between the output voltage control and the input voltage sharing control is realized.

Description

technical field [0001] The invention belongs to the technical field of power electronic transformers, and more specifically relates to a decoupling control method and device for a DAB converter with an input in series and an output in parallel. Background technique [0002] With the consumption of traditional fossil energy and environmental pollution problems becoming more and more serious, distributed energy represented by wind power generation and photovoltaic power generation has been widely valued for its advantages of environmental protection, flexible configuration, and nearby power transmission. Especially with the development of smart grid, the flexible access of distributed energy and energy storage units has become an important goal in the development of smart grid. The development of DC grid can effectively solve the contradiction between distributed energy and large power grid, increase the proportion of renewable energy in the grid system, and give full play to ...

AI Technical Summary

Problems solved by technology

However, there is still coupling between the control loops, which makes the input signal of each control loop in the system affect the output of all loops, and the output of each loop will be affected by all inputs.

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