Single-phase phase-locked loop optimization design method with harmonic suppression function

Abstract

The invention provides a single-phase phase-locked loop optimization design method with a harmonic suppression function. The invention has the improvement that the design method comprises the steps of: firstly, establishing a single-phase phase-locked loop small-signal model, carrying out equivalent processing on the small-signal model to form a one-order inertial element and a proportional element, and establishing a complete single-phase phase-locked loop small-signal model; secondly, designing a control parameter of a single-phase phase-locked loop, and solving a value range of the control parameter by using an open-loop transfer function and an error transfer function of the single-phase phase-locked loop small-signal model as target functions and using single-phase phase-locked loop dynamic characteristics as constraint conditions; and finally, according to a transfer function of an interference signal, optimizing the control parameter of the single-phase phase-locked loop. The design method provided by the invention is applicable to different single-phase phase-locked loops, can be directly applied to application environments with different requirements for the harmonic suppression function, and is convenient to evaluate advantages and disadvantages of performances of different single-phase phase-locked loops.

Description

technical field [0001] The invention relates to the field of power electronics, in particular to an optimal design method for a single-phase phase-locked loop with a harmonic suppression function. Background technique [0002] Synchronization technology that plays an important role in power conversion systems can be used in technical fields such as uninterruptible power supplies, distributed power generation technology, energy storage systems, and active filters. The phase-locked loop is a very important component of the grid-connected inverter in the new energy and energy storage grid-connected operation and control. The phase-locked loop generally includes three modules: 1) Phase Detector (PD), 2 ) Loop Filter (Loop Filter, LP), 3) Voltage Controlled Oscillator (Voltage Controlled Oscillator, VCO). [0003] The single-phase system has less voltage and current information of two phases than the three-phase system. In order to accurately track the phase angle of the power g...

AI Technical Summary

Problems solved by technology

In addition, in the design process, more consideration is given to the compromise between stability and rapidity in the selection of control parameters, and the influence of the harmonic suppression function of the single-phase phase-locked loop on the control parameters is not considered.

This design concept cannot fully reflect the dynamic characteristics of the entire single-phase phase-locked loop, and there is currently no optimal design method for systematically analyzing the dynamic characteristics of the entire single-phase phase-locked loop

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