A self-adaptive method of microgrid protection setting value
A protection fixed value, micro-grid technology, applied in the direction of emergency protection circuit devices, automatic disconnection emergency protection devices, electrical components, etc., can solve the problem of less adaptability of transformer bus protection, poor reliability, difficult reliability and Selectivity and other issues to achieve the effect of ensuring the sensitivity of the protection action, wide adaptability, and the reliability of the protection action
Active Publication Date: 2021-08-13
NARI TECH CO LTD
View PDF0 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0005] 1) Limitations: Most of the current adaptive methods are limited to line protection for the research objects, and there are few introductions about the adaptability of transformer protection and busbar protection.
Most of the protection principles focus on distance protection and overcurrent protection, and there are few introductions to the adaptive implementation of other protection principles
[0006] 2) Dependency: The current self-adaptive method is transitionally dependent on in-station device information and scheduling system information. If there is a problem with the dependent equipment or system, it will inevitably lead to protection self-adaptive criteria, so the reliability of the dependent transition scheme must be poor
[0008] Moreover, it is impossible to rely on a set of fixed values to satisfy all the operation modes of the power grid. Greatly increase the burden of protecting the setting personnel
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 moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0055] The present invention will be further described below. The following examples are only used to illustrate the technical solution of the present invention more clearly, but not to limit the protection scope of the present invention.
[0056] The present invention provides a calculation method of microgrid protection fixed value based on floating threshold fixed value, including:
[0057] The protection setting is composed of fixed setting + floating setting, expressed as follows: S op = S fixed +S float
[0058] Among them, S op is the protection setting, S fixed It is a fixed value, and the fixed value needs to avoid errors such as current transformers and device precision currents, S floatIt is a floating fixed value, and the floating fixed value is different for different protection objects and different protection criteria.
[0059] The power flow of the microgrid changes greatly, and the floating fixed value is subject to the load current, and the load curren...
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
Login to View More Abstract
The invention discloses a self-adaptive method for the fixed value of micro-grid protection. According to the protection type, two modes of adjusting the fixed value of the floating threshold and switching between the fixed value area are supported; for the method of adjusting the fixed value of the floating threshold, the fixed value of the protection is changed Composed of fixed value + floating fixed value, the floating fixed value is subject to the load current, and the microgrid power flow change adopts the floating threshold technology to realize automatic tracking and adjustment, and does not need to re-adjust the fixed value every time the power flow current changes, so as to achieve coordination with the current operation and maintenance mode . For protection components that do not use floating thresholds, the microgrid sets the protection settings corresponding to different operation modes according to different operation modes, and switches the fixed value area according to the real-time judgment of the operation mode during operation to achieve coordination with the current operation and maintenance mode.
Description
technical field [0001] The invention relates to a self-adaptive method for a micro-grid protection fixed value, which belongs to the technical field of electric power system relay protection. Background technique [0002] Compared with the traditional power grid, the operating characteristics and fault characteristics of the microgrid have the following characteristics: the operation mode is flexible, and there are two modes of grid-connected operation and off-grid operation; 1) the distribution line is shorter; 2) the original single distribution is changed 3) The multi-source nature of the microgrid may cause the power flow flowing through the terminal equipment to be bidirectional; 4) The power failure characteristics are complex; 5) The load is asymmetrical in three phases. [0003] The setting calculation of power system relay protection setting value is an important work of relay protection specialty in dispatching departments at all levels. With the increasing expans...
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
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): H02H3/00H02H7/26
CPCH02H3/006H02H7/26
Inventor 李志坚张海滨郑玉平王伟梅德冬潘书燕侯宇许广婷董璇
Owner NARI TECH CO LTD