Large-signal decomposition decoupling control method and device for buck converter

Abstract

The invention discloses a large signal decomposition and decoupling control method and device of a buck converter. The method includes: decomposing the converter system into a disturbance part, a current loop controlled object and a voltage loop controlled object to construct a large signal of the converter Circuit model; Feed-forward decoupling for the disturbance part; Inverse system decoupling and linear feedback for the current loop controlled object to compensate it into a pseudo-linear system, so that the compensated current loop open-loop transfer function is a first-order pure integral link ; and perform inverse system decoupling and linear feedback on the controlled object of the voltage loop to compensate it into a pseudo-linear system, so that the compensated open-loop transfer function of the voltage loop is a unit system. The invention can separately control the disturbance part, the controlled object of the current loop and the controlled object of the voltage loop, so that the disturbance control of the buck converter, the control of the dynamic characteristics of the voltage loop and the control of the dynamic characteristics of the current loop become independent processes that do not affect each other , to achieve decoupling control.

Description

technical field [0001] The invention relates to the technical field of power electronic converter control, in particular to a large-signal decomposition and decoupling control method and device for a buck converter. Background technique [0002] Small-signal modeling of buck converter and linear feedback control is a mature analysis and research method at present, but this method has the following limitations: (1) The product term of duty cycle and input voltage or state variable is ignored, thus It is required that the amount of disturbance must be much smaller than the DC operating point; (2) In actual analysis, the disturbance of DC power supply and load is usually ignored, and it is simplified to a single-input single-output system, which leads to a large margin in the designed controller and cannot guarantee The working performance of the converter under large signal disturbance and wide range operation. [0003] With the development of new energy distributed DC power ...

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Problems solved by technology

[0007] The purpose of the present invention is to provide a large-signal decomposition and decoupling control method and device for a buck converter, so as to overcome the limitations of the small-signal modeling method of the buck converter and the very complicated design of the controller due to the coupling relationship of the buck converter shortcoming

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