Check patentability & draft patents in minutes with Patsnap Eureka AI!

A dual-loop PID compound control method and system for isolated grid frequency

A compound control, dual-loop technology, applied in the direction of single-network parallel feeding arrangement, reducing/preventing power oscillation, etc., can solve problems such as endangering the safe and stable operation of enterprises, frequency instability, etc., achieving small overshoot, fast dynamic response, Guarantee the effect of frequency stability

Active Publication Date: 2022-07-22
NR ELECTRIC CO LTD +1
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the embodiments of the present invention is to provide a dual-loop PID composite control method and system for isolated grid frequency control, to optimize the anti-disturbance capability of the steam turbine DEH in isolated grid operation, improve the frequency dynamic performance of the isolated grid, and solve the problem of isolated grid frequency. In some unexpected situations, the network is prone to frequency instability, which endangers the safe and stable operation of enterprises.

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
  • A dual-loop PID compound control method and system for isolated grid frequency
  • A dual-loop PID compound control method and system for isolated grid frequency

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046]The fast secondary frequency regulation function is added to the DEH system of the isolated generator set. The secondary frequency regulation function includes the outer loop fuzzy self-tuning PID control and the inner loop traditional PID control; when the speed deviation is greater than the switching threshold, the outer loop is used for fuzzy self-tuning PID control , when it is less than the switching threshold, the traditional PID control is carried out through the inner loop.

[0047] Specifically, it includes the following steps:

[0048] S1: Add the fast secondary frequency modulation function to the DEH system of the isolated generator set.

[0049] S2: Set the fuzzy subset, fuzzy reasoning and defuzzification rules of the fuzzy self-tuning PID controller of the DEH fast secondary frequency modulation outer loop.

[0050] The fuzzy self-tuning PID control specifically includes the following steps:

[0051] S21: The speed deviation and the rate of change of the...

Embodiment 2

[0063] figure 1 It is a schematic diagram of the isolated grid frequency control method of the dual-loop PID composite control provided by the embodiment of the present invention. When the enterprise operates in the isolated network mode, the generator set no longer accepts the dispatched load command, and the primary frequency regulation function of the unit itself cannot completely eliminate the frequency deviation. Therefore, a fast secondary frequency regulation function is added to the DEH system to adjust the DEH power supply in real time. The fixed value can balance the power generation and the power consumption, and further realize the stability of the frequency of the isolated grid. When the deviation between the frequency fluctuation of the isolated grid and the rated speed exceeds the first threshold E 1 time (in this example, E 1 Take 15rpm), automatically turn on the fast secondary frequency modulation function, when the deviation between the isolated grid frequ...

Embodiment 3

[0071] The present invention accordingly proposes an isolated grid frequency control system with dual-loop PID composite control. A fast secondary frequency modulation control unit is added to the DEH system of an isolated generator set, and the secondary frequency modulation control unit includes an outer loop fuzzy self-tuning PID control sub-unit. , Inner loop traditional PID control sub-unit and switching sub-unit;

[0072] The switching subunit is used to enable the outer loop fuzzy self-tuning PID control subunit when the rotational speed deviation is greater than the switching threshold, and enable the inner loop traditional PID control subunit when it is smaller than the switching threshold.

[0073] In a preferred embodiment, the fast secondary frequency modulation control unit further includes a fast secondary frequency modulation function switching sub-unit, which is used to control when the deviation between the frequency fluctuation of the isolated grid and the rat...

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 present invention provides an isolated grid frequency control method of dual-loop PID composite control. A fast secondary frequency regulation function is added to the DEH system of an isolated generator set. The secondary frequency regulation function includes an outer loop fuzzy self-tuning PID control and an inner loop traditional PID control. ; When the speed deviation is greater than the switching threshold, the fuzzy self-tuning PID control is carried out through the outer loop, and the traditional PID control is carried out through the inner loop when the speed deviation is less than the switching threshold. The invention also discloses a corresponding control system. Fuzzy self-tuning PID has the advantages of flexible control and strong adaptability, supplemented by non-disturbance switching to traditional PID in the event of small deviation to quickly eliminate static error, so that the entire fast secondary frequency modulation loop has fast dynamic response, small overshoot and robustness. The characteristics of strong control and precise control effect ensure the stable frequency of isolated network operation and maintain the production safety of enterprises.

Description

technical field [0001] The invention relates to the field of isolated grid frequency control, in particular to a dual-loop PID composite control method and system for isolated grid frequency control. Background technique [0002] At present, the common problems existing in the power grid industry of enterprises are the weak connection with the large power grid, which is easy to form an isolated grid, and the self-balancing ability of the power grid is poor. In industries that require uninterrupted power supply and high voltage quality, such as chemical industry, short-term failure of large power grids may directly lead to production interruption, resulting in serious economic losses and environmental pollution. Therefore, improving the safety and reliability of power grids of industrial enterprises is an important issue of enterprise power grids. As one of the most important equipments in the entire power generation system, the steam turbine's control system (DEH) runs thro...

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 Patents(China)
IPC IPC(8): H02J3/24H02J3/46
CPCH02J3/24H02J3/46
Inventor 宋诚骁牛洪海蔡丹李彦龙
Owner NR ELECTRIC CO LTD
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

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

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com