CN-121984005-A - Hybrid active filter cooperative control method, system, equipment and medium based on golden section optimization

CN121984005ACN 121984005 ACN121984005 ACN 121984005ACN-121984005-A

Abstract

The invention belongs to the technical field of power grid harmonic control, and discloses a hybrid active filter cooperative control method, system, equipment and medium based on golden section optimization, which aim to solve the problems of single function, low capacity utilization rate and poor power grid adaptability. The method comprises the steps of firstly obtaining harmonic voltage signals at a load side of a public connection point of a power grid and harmonic current signals at the power grid side, calculating capacity utilization efficiency, then constructing a dual-channel control framework, enabling a first channel to generate a current type compensation instruction according to harmonic current, enabling a second channel to generate a resistance type compensation instruction according to harmonic voltage, then solving weight coefficients of the two channels in real time by adopting a golden section search algorithm with the aim of maximizing the capacity utilization efficiency, enabling the instructions of the two channels to be subjected to weighted superposition to generate a total harmonic compensation instruction, and finally controlling a hybrid active filter to inject compensation current into the power grid. The invention realizes the cooperative control of double-side harmonic sources, the improvement of capacity utilization rate and the self-adaptive adjustment of the power grid strength.

Inventors

XU QUNWEI
LI PEI
PAN XING
WANG SONG
ZHU FEIBAI
MA ZHIQUAN

Assignees

国网浙江省电力有限公司电力科学研究院

Dates

Publication Date: 20260505
Application Date: 20260408

Claims (10)

1. A hybrid active filter cooperative control method based on golden section optimization is characterized by comprising the following steps: S1, acquiring a harmonic voltage signal at a load side of a public connection point of a power grid and a harmonic current signal at the power grid side; S2, calculating capacity utilization efficiency of the hybrid active filter at the current moment based on the harmonic voltage signal and the harmonic current signal; S3, constructing a dual-channel control framework of the hybrid active filter, wherein a first channel is used for realizing a current type active filtering function and generating a first current reference instruction according to harmonic current at the power grid side, and a second channel is used for realizing a resistance type active filtering function and generating a second current reference instruction according to harmonic voltage at a public connection point; S4, aiming at maximizing the capacity utilization efficiency, adopting a golden section searching algorithm to solve the weight coefficient of the first channel and the weight coefficient of the second channel in real time; s5, according to the solved weight coefficient of the first channel and the solved weight coefficient of the second channel, the first current reference instruction and the second current reference instruction are subjected to weighted superposition to generate a total harmonic compensation current instruction; and S6, controlling the hybrid active filter to inject compensation current into the power grid according to the total harmonic compensation current command.
2. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 1, wherein: The capacity utilization efficiency is used for representing the suppression efficiency of the output current of the hybrid active filter on harmonic resonance, and the numerical value of the capacity utilization efficiency is determined by the amplitude of the output current of the hybrid active filter, the phase of the output current and the deviation between the impedance angles of the power grid; The phase of the output current of the hybrid active filter is determined by the weight coefficient of the first channel, the first current reference command, the weight coefficient of the second channel and the second current reference command.
3. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 2, wherein: And the sum of the weight coefficient of the first channel and the weight coefficient of the second channel is 1, and the continuous adjustment of the output current phase of the hybrid active filter is realized by adjusting the proportion of the weight coefficient of the first channel and the weight coefficient of the second channel.
4. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 1, wherein step S4 comprises: s41, initializing a search range in a preset interval, selecting two inner points in the search range according to the golden section proportion, and respectively calculating capacity utilization efficiency values corresponding to the two inner points; s42, reducing the search range according to the comparison result of the capacity utilization rate efficiency values of the two inner points; s43, performing iteration on the steps S41 to S42 until the search range meets a preset iteration termination condition; S44, determining the optimal solution of the weight coefficient of the first channel and the weight coefficient of the second channel according to the final search range.
5. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 4, wherein: the preset interval is [0,1]; The iteration termination condition is that the width of the search range is smaller than a preset threshold value or the number of iterations reaches a preset maximum value; And determining an optimal solution according to the final search range, wherein the optimal solution comprises taking the midpoint of the final search range as the optimal solution of the weight coefficient of the first channel.
6. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 5, wherein: the preset threshold value is 0.01, and the preset maximum iteration number is 15.
7. The hybrid active filter cooperative control method based on golden section optimization as claimed in claim 1, wherein after solving in step S4 to obtain the weight coefficient of the first channel and the weight coefficient of the second channel, the method further comprises a smoothing step: Filtering the obtained weight coefficient of the first channel and the obtained weight coefficient of the second channel to obtain a smoothed weight coefficient for weighted superposition in the step S5; The time constant of the filtering process is set to 20 to 50 milliseconds for suppressing system impact caused by abrupt change of the weight coefficient.
8. A hybrid active filter cooperative control system based on golden section optimization, characterized by being used for realizing the hybrid active filter cooperative control method as claimed in any one of claims 1 to 7, comprising: the signal detection module is used for acquiring harmonic voltage signals at the load side of the public connection point of the power grid and harmonic current signals at the power grid side; the capacity utilization rate calculation module is used for calculating the capacity utilization rate efficiency of the hybrid active filter at the current moment based on the harmonic voltage signal and the harmonic current signal; The dual-channel construction module is used for constructing a dual-channel control framework of the hybrid active filter, wherein a first channel is used for realizing a current type active filtering function and generating a first current reference instruction according to harmonic current at the power grid side, and a second channel is used for realizing a resistance type active filtering function and generating a second current reference instruction according to harmonic voltage at a public connection point; The weight solving module is used for solving the weight coefficient of the first channel and the weight coefficient of the second channel in real time by adopting a golden section searching algorithm with the aim of maximizing the capacity utilization efficiency; the instruction generation module is used for carrying out weighted superposition on the first current reference instruction and the second current reference instruction according to the solved weight coefficient of the first channel and the solved weight coefficient of the second channel to generate a total harmonic compensation current instruction; and the control execution module is used for controlling the mixed active filter to inject compensation current into the power grid according to the total harmonic compensation current command.
9. A computer device comprising a memory, a processor and a computer program, wherein the computer program when executed by the processor implements the hybrid active filter cooperative control method of any of claims 1 to 7.
10. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the hybrid active filter cooperative control method according to any one of claims 1 to 7.

Description

Hybrid active filter cooperative control method, system, equipment and medium based on golden section optimization Technical Field The invention belongs to the technical field of power grid harmonic control, and particularly relates to a hybrid active filter cooperative control method, system, equipment and medium based on golden section optimization. Background With the wide application of nonlinear loads and power electronics in modern power systems, grid harmonic pollution presents a multi-source and complicating feature. In the scenes of high-voltage direct-current transmission, industrial traction power supply and the like, a load side harmonic current source and a power grid side background harmonic voltage source exist at the same time, harmonic resonance is easy to occur due to interaction of the load side harmonic current source and the power grid side background harmonic voltage source, and the electric energy quality is deteriorated. The traditional passive filter can only treat specific subharmonics, has limited suppression effect on non-characteristic subharmonics, and can generate series-parallel resonance with system impedance to amplify background harmonics. The active filter can effectively improve the electric energy quality by constructing controllable harmonic impedance through the power electronic converter. The existing control strategy mainly comprises two types, namely resistive active filtering control, current source active filtering control and load harmonic current direct offset, wherein the resistive active filtering control enables the device to present virtual resistance characteristics in a harmonic domain and provides damping for a system to inhibit resonance, and the current source active filtering control enables the device to be equivalent to a harmonic current source. The method has good effect under the single type harmonic source scene, but in a complex system with double harmonic sources at the same time, the single active filter mode is difficult to realize global optimal treatment. Specifically, the resistive active filter suppresses resonance through virtual damping, but has weak active cancellation capability on load harmonic current, the harmonic suppression effect depends on the impedance characteristic of the system, the treatment effect is poor when the intensity of a harmonic current source is high, the current source active filter can accurately track and cancel the load harmonic current, but the equivalent current source characteristic of the current source active filter cannot provide effective damping for the system, resonance is easy to be induced when the impedance of a power grid is high, and even voltage distortion is aggravated. In addition, in the prior art, a single virtual impedance model is adopted, the voltage and current constraint of the common connection point only serves a single control target, two independent degrees of freedom of harmonic current suppression and resonance suppression cannot be optimized at the same time under a complex scene, the control phase angle deviates from global optimum, and the current utilization rate of the device is generally low. There are also significant disadvantages to the prior art in terms of grid adaptability. Under the condition of weak current network, the coupling effect of the current source characteristic of the current source active filter and the impedance of the power grid is enhanced, the system damping is insufficient, harmonic oscillation is easy to occur, and under the condition of strong power grid, the resistive active filter needs extremely small virtual resistance value to provide effective damping, the digital controller quantization error and delay cause the rapid reduction of the phase margin, and the control stability is deteriorated. In the prior art, a self-adaptive mode switching mechanism based on power grid impedance is not established, control parameters are fixed, and stability is difficult to maintain in a full working condition range. In summary, the existing active filtering technology has the problems of single function, low capacity utilization rate and poor power grid adaptability, and is difficult to realize cooperative treatment in complex scenes with coexistence of double harmonic sources. Disclosure of Invention Based on the above-mentioned drawbacks and disadvantages of the prior art, one of the objects of the present invention is to solve at least one or more of the above-mentioned problems of the prior art, in other words, one of the objects of the present invention is to provide a hybrid active filter cooperative control method, system, device and medium based on golden section optimization that meets one or more of the above-mentioned needs, so as to achieve the purpose of achieving cooperative control of load side harmonic current cancellation and network side harmonic resonance suppression under a complex scenario where two side harmonic sources coexist, and