Flexible direct-current high-frequency resonance suppression method, system and equipment

A flexible DC and high-frequency resonance technology, which is applied to AC networks to reduce harmonics/ripples, AC network circuits, harmonic reduction devices, etc., can solve problems such as deteriorating dynamic characteristics of power systems

Active Publication Date: 2020-10-20
ELECTRIC POWER RESEARCH INSTITUTE, CHINA SOUTHERN POWER GRID CO LTD +1
View PDF9 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The present invention provides a flexible DC high-frequency resonance suppression method, system and equipment, which are used to solve the problem of deteriorating the dynamic characteristics of the power system when filters are used to suppress the high-frequency resonance of flexible DC transmission lines in the prior art technical problem

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Flexible direct-current high-frequency resonance suppression method, system and equipment
  • Flexible direct-current high-frequency resonance suppression method, system and equipment
  • Flexible direct-current high-frequency resonance suppression method, system and equipment

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0056] Such as figure 1 As shown, this embodiment provides a flexible DC high-frequency resonance suppression method, which is suitable for pre-installing a virtual grid adaptive filter in the feedforward link of the flexible DC current inner loop controller. The method includes the following steps:

[0057] S1: Real-time detection of the dq-axis components of the actual AC voltage of the flexible direct current transmission line through the sensor, and calculation of the effective value of the actual AC voltage according to the dq-axis components of the actual AC voltage, where the calculation formula for the effective value of the actual AC voltage is:

[0058]

[0059] Among them, V sd , V sq are the voltage of the d-axis component and the voltage of the q-axis component in the dq-axis components, respectively.

[0060] S2: Compare the effective value of the actual AC voltage with the preset voltage threshold, the voltage threshold ranges from 0.7pu to 0.9pu; if the ef...

Embodiment 2

[0064] Such as figure 1 As shown, a flexible DC high-frequency resonance suppression method provided in this embodiment is suitable for pre-installing a virtual grid adaptive filter in the feedforward link of a flexible DC transmission line. The method includes the following steps:

[0065] S1: Real-time collection of the actual AC voltage of the flexible DC transmission line,

[0066] Transform the actual AC voltage in the dq coordinate system to obtain the positive-sequence dq-axis component and the negative-sequence dq-axis component of the actual AC voltage, where the dq-axis component includes the d-axis component and the q-axis component, according to the actual AC voltage positive sequence dq The axis component and the negative sequence dq axis component calculate the effective value of the actual AC voltage. The formula for calculating the effective value of the actual AC voltage is:

[0067]

[0068] Among them, V sd , V sq are the voltage of the d-axis componen...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a flexible direct-current high-frequency resonance suppression method, system and equipment. The method comprises the steps of enabling the input quantity and output quantity of a virtual power grid adaptive filter to be completely isolated physically under a normal condition, enabling the harmonic waves of an actual electrical quantity not to be reflected on the virtual electrical quantity, and achieving an effect of suppressing the harmonic waves. When the effective value of the actually input actual alternating-current voltage is reduced to meet the preset conditionfrom the normal value, the virtual electrical quantity is enabled to be completely equal to the actual electrical quantity, the complete real-time tracking of the actual electrical quantity is realized, and the dynamic characteristic of the power system at the fault moment is improved; and after completely tracking for a period of time, if the effective value of the actual alternating-current voltage is smaller than a preset threshold value, adaptive tracking is carried out until the actual electrical quantity is recovered to a stable value. According to the method, the risk of high-frequencyresonance of the flexible direct current can be reduced, deterioration of dynamic characteristics of the flexible direct current under the fault working condition is avoided, damage to devices or equipment due to overstress is avoided, and the safety of flexible direct current fault ride-through is improved.

Description

technical field [0001] The invention relates to the field of electric power, in particular to a method, system and equipment for suppressing flexible DC high-frequency resonance. Background technique [0002] Flexible DC transmission is the trend of future power system development. There are several key technical problems that need to be solved in the application of flexible DC transmission, one of which is to suppress the high-frequency resonance between the flexible DC and AC systems. The resonance caused by the negative impedance of the flexible DC converter amplifying the system harmonics is mainly caused by the impedance mismatch between the flexible DC converter and the AC system. This resonance is mainly related to control link delay and feedforward strategy. For this resonance, the main solution in the current flexible DC project is to reasonably configure the filter strategy in the feedforward link of the inner loop controller of the flexible DC station. Studies ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H02J3/36H02J3/01
CPCH02J3/36H02J3/01H02J2003/365Y02E40/40Y02E60/60H02J3/00125H02J3/24H02J3/241H02J3/06
Inventor 饶宏李桂源黄伟煌李岩许树楷
Owner ELECTRIC POWER RESEARCH INSTITUTE, CHINA SOUTHERN POWER GRID CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap