Frequency-locked loop construction method based on generalized three-order integrator

Abstract

The invention discloses a frequency-locked loop construction method based on a generalized three-order integrator, and belongs to the field of signal processing. The construction method comprises thefollowing steps: according to a group of phasors of a three-phase system, firstly filtering harmonic signals in two-phase signals by using a frequency selection network consisting of a generalized third-order integrator, a generalized second-order integrator and a direct-current filter ring, generating corresponding orthogonal signals and error signals, and then constructing a frequency locking ring by using the error signals and the orthogonal signals. Compared with a traditional scheme, the frequency-locked loop structure provided by the invention has the advantages that the response speed is increased while the overshoot is not increased.

Description

technical field [0001] The invention relates to the field of signal processing, in particular to a construction method of a frequency-locked loop based on a generalized third-order integrator. Background technique [0002] Three-phase systems widely exist in production and life, such as permanent magnet synchronous motors, power grids, etc. Frequency is an important parameter for three-phase systems. Accurate frequency acquisition technology plays an important role in many applications, such as speed sensorless control of permanent magnet synchronous motors, new energy grid connection, etc. [0003] The three-phase system frequency acquisition methods introduced in existing academic papers are mainly divided into methods based on statistical ideas represented by Kalman filters, phase-locked loop methods represented by synchronous coordinate system phase-locked loops, and methods based on generalized The frequency-locked loop of the second-order integrator is the representa...

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Problems solved by technology

[0007] 1. Insufficient ability to suppress high-frequency interference signals;

[0008] 2. When the system frequency changes step by step, it is difficult to take into account the response time and overshoot of the output frequency estimate;

[0009] 3. While improving the response speed of the frequency estimation value of the three-phase system, it is difficult to ensure that the overshoot will not increase

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