Composite current constraint control method of direct-current buck converter

Abstract

The invention discloses a composite current constraint control method of a direct-current buck converter. The method comprises: a state space averaging model of a direct-current buck converter nominal system is established by using a capacitor voltage and an inductor current of the direct-current buck converter as state quantities; a reference current constraint controller is established; according to parameter perturbation of the direct-current buck converter system, input voltage fluctuation and load sudden-change disturbance, a disturbed-state averaging model of the direct-current buck converter is established; a generalized proportional-integral observer is constructed and a time-varying disturbance estimation value is obtained; the reference current constraint controller is introduced to carry out compensation on time-varying disturbance to obtain a composite current constraint controller; and calculation is carried out to obtain a controlled quantity, the controlled quantity is outputted by an output module to obtain a PWM drive signal, and a switching tube of the buck converter is controlled, thereby realizing voltage control of the buck converter. Therefore, requirements of high rapidness and accuracy of output voltage tracking and the anti-disturbance performance of the system can be met while the current constraint function is met.

Description

technical field [0001] The invention relates to a compound current constraint control method of a direct current step-down converter, belonging to the technical field of power electronic converters. Background technique [0002] With the deteriorating global environment and the shortage of traditional fossil energy, efforts to develop renewable new energy have become the consensus of all countries. This greatly promotes the wide application of new energy-oriented DC step-down converter systems in various voltage regulation systems. The DC buck converter system plays an extremely important role in it, and its applications include: high-voltage DC power transmission and distribution systems, solar photovoltaic power generation systems, electric vehicle systems, industrial automation systems, and military aerospace systems. The output voltage response speed, anti-disturbance ability and tracking accuracy of the buck converter all play a vital role in the electrical equipment c...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art, provide a compound current constraint control method for a DC step-down converter, and solve the problem that the controller cannot take into account the dynamics of the output voltage while implementing the instantaneous current constraint on startup. Response and anti-disturbance performance problems, combined with dynamic gain constraint algorithm and generalized proportional integral observer, to achieve the protection of the starting current of the DC buck converter, while taking into account the requirements of the system's output voltage tracking speed, accuracy and anti-disturbance performance

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