阅读说明：本技术 一种氧化锌电阻片均能配组方法 (Zinc oxide resistance card homoenergetic matching method ) 是由 张泽林 黄辉兴 曹忺 刘斌 于 2020-05-24 设计创作，主要内容包括：本发明属于电力系统技术领域,尤其为一种氧化锌电阻片均能配组方法,包括氧化锌阀片静态伏安特性正态分布特性构建、氧化锌阀片能量分布特性构建以及基于正态分布规律的氧化锌阀片均能配组三个过程；首先提出了氧化锌阀片静态伏安特性正态分布规律,其次提出了氧化锌阀片均能原理,最后提出正态分布规律的氧化锌阀片均能配组方法,将能量吸收差异最大的两柱避雷器中吸能差异最大的电阻片对调,并多次迭代,实现避雷器组各避雷器柱的电流不均匀系数最小,实现能量的均匀分配,能够有效的减小避雷器组的电流不均匀系数,实现能量的均匀分配,可以实现多柱氧化锌避雷器并联均能,提高避雷器组运行可靠性。(The invention belongs to the technical field of power systems, and particularly relates to a zinc oxide resistance sheet homoenergetic matching method which comprises three processes of zinc oxide valve sheet static volt-ampere characteristic normal distribution characteristic construction, zinc oxide valve sheet energy distribution characteristic construction and zinc oxide valve sheet homoenergetic matching based on a normal distribution rule; the normal distribution rule of the static volt-ampere characteristics of the zinc oxide valve plates is provided firstly, the homoenergetic principle of the zinc oxide valve plates is provided secondly, and finally, the homoenergetic matching method of the zinc oxide valve plates with the normal distribution rule is provided.)

1. A zinc oxide resistance card homoenergetic matching method is characterized by comprising the following steps: the method comprises three processes of zinc oxide valve plate static volt-ampere characteristic normal distribution characteristic construction, zinc oxide valve plate energy distribution characteristic construction and normal distribution rule-based zinc oxide valve plate homoenergetic matching.

2. The construction of the normal distribution characteristic of the static volt-ampere characteristic of the zinc oxide valve plate according to claim 1, is characterized in that: according to the reference voltage measurement data of the m resistance cards U1mA, the normal distribution characteristic of the reference voltage is constructed, and the normal distribution U1 mA-N (mu, sigma) is met²)。

3. The zinc oxide valve plate energy distribution characteristic construction of claim 2, wherein: and performing exponential function fitting and characteristic curve fitting on the static volt-ampere characteristic of the zinc oxide valve plates according to the static volt-ampere characteristic (V-A) of the m zinc oxide valve plates.

4. The zinc oxide valve plate energy distribution characteristic construction of claim 3, wherein: the exponential function I ═ A × U^B+ C, where A, B, C is the fitting coefficient.

5. The zinc oxide resistance card group matching method according to claim 4, wherein the method comprises the following steps: the method comprises the following steps:

s1, selecting parameter requirements of the lightning arrester group and resistance cards, and determining the number of each column and the number of parallel columns of the lightning arrester;

s2, determining the reference voltage of the lightning arrester group at the position by a normal distribution curve, determining the current waveform of each column through an exponential function, and calculating the energy absorption of each resistance card under the current waveform through fitting;

s3, arranging the resistance cards into columns and generating a serial number matrix, directly adding volt-ampere characteristic points of the resistance cards in one column to obtain a whole column volt-ampere characteristic, and performing exponential function fitting on each column volt-ampere characteristic;

s4, calculating current flowing through each column according to the overall residual voltage waveform of the lightning arrester group;

s5, calculating voltage waveforms borne by the resistance cards according to the current-voltage characteristic fitting function of the resistance cards, and then calculating energy through W ═ U (t) × I (t) dt;

s6, iteratively adjusting the positions of the resistance cards according to the energy absorption matrix, and exchanging the position of the resistance card with the minimum absorption energy of the current maximum column with the position of the resistance card with the maximum absorption energy of the current minimum column;

and S7, repeating the steps from S4 to S6 until the current unevenness coefficient requirement is met.

Technical Field

The invention belongs to the technical field of power systems, and particularly relates to a zinc oxide resistance card homoenergetic matching method.

Background

The lightning arrester is a main device used for lightning protection of an electric power system, the zinc oxide resistance card is a core component in the lightning arrester, the zinc oxide resistance card is a functional composite ceramic material, and has the characteristics of excellent nonlinear resistance characteristic, high through-current capacity and the like, so that the zinc oxide resistance card plays important roles of limiting overvoltage amplitude and absorbing overvoltage energy in the zinc oxide lightning arrester, and is widely applied to the electric power system as the core component of the lightning arrester to protect electric equipment from being damaged by overvoltage such as lightning and the like, the difference of the volt-ampere characteristics of the lightning arrester group can cause uneven current distribution, the lightning arrester with poor volt-ampere characteristics is accelerated aged or even broken down, and serious safety problems are caused.

Therefore, the technical field provides a method for matching zinc oxide resistance cards to solve the problems in the background.

Disclosure of Invention

To solve the problems set forth in the background art described above. The invention provides a zinc oxide resistor sheet homoenergetic matching method which has the characteristics of effectively reducing the volt-ampere characteristic difference of each arrester column, relieving the problem of uneven current distribution and improving the protection performance of an arrester group.

In order to achieve the purpose, the invention provides the following technical scheme: a zinc oxide resistance sheet homoenergetic matching method comprises three processes of zinc oxide valve sheet static volt-ampere characteristic normal distribution characteristic construction, zinc oxide valve sheet energy distribution characteristic construction and zinc oxide valve sheet homoenergetic matching based on a normal distribution rule.

Preferably, a normal distribution characteristic of the reference voltage is constructed according to the reference voltage measurement data of the m-piece resistive sheet U1mA, and the normal distribution U1 mA-N (mu, sigma) is satisfied²) (wherein m is greater than 20, and μ is the mean value of reference voltages, σ, of m resistive sheets U1mA²Is the standard deviation of the reference voltage of the m resistive patches U1 mA).

Preferably, the static volt-ampere characteristics of the zinc oxide valve plates are subjected to exponential function fitting and characteristic curve fitting according to the static volt-ampere characteristics (V-A) of m zinc oxide valve plates, the voltage waveform borne by each resistance plate is calculated according to the current fitting tool box power2 of MAT L AB and the current-ampere characteristic fitting function of the zinc oxide valve plates, and finally the energy is calculated through W ═ U (t) × I (t) dt.

Preferably, the exponential function I ═ a × U^B+ C, where A, B, C is the fitting coefficient.

A zinc oxide resistance card group matching method comprises the following steps:

s1, selecting parameter requirements of the lightning arrester group and resistance cards, and determining the number of each column and the number of parallel columns of the lightning arrester;

s2, determining the reference voltage of the lightning arrester group at the position by a normal distribution curve, determining the current waveform of each column through an exponential function, and calculating the energy absorption of each resistance card under the current waveform through fitting;

s3, arranging the resistance cards into columns and generating a serial number matrix, directly adding volt-ampere characteristic points of the resistance cards in one column to obtain a whole column volt-ampere characteristic, and performing exponential function fitting on each column volt-ampere characteristic;

s4, calculating current flowing through each column according to the overall residual voltage waveform of the lightning arrester group;

s5, calculating voltage waveforms borne by the resistance sheets according to a resistance partial self volt-ampere characteristic fitting function, and then calculating energy through W ═ U (t) × I (t) dt;

s6, iteratively adjusting the positions of the resistance cards according to the energy absorption matrix, and exchanging the position of the resistance card with the minimum absorption energy of the current maximum column with the position of the resistance card with the maximum absorption energy of the current minimum column;

and S7, repeating the steps from S4 to S6 until the current unevenness coefficient requirement is met.

Compared with the prior art, the invention has the beneficial effects that:

1. the zinc oxide valve plates can be matched to effectively reduce the volt-ampere characteristic difference of each lightning arrester column, relieve the problem of uneven current distribution and improve the protection performance of the lightning arrester group;

2. exchanging the resistance sheets with the largest energy absorption difference in the two columns of arresters with the largest energy absorption difference, and iterating for multiple times to realize the minimum current uneven coefficient of each arrester column of the arrester group, realize the uniform distribution of energy and improve the protection performance of the arrester group;

3. the current non-uniform coefficient of the arrester group can be effectively reduced, the uniform distribution of energy is realized, the protection performance of the arrester group is improved, the parallel homoenergetic of the multi-column zinc oxide arrester can be realized, and the operation reliability of the arrester group is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of the grouping algorithm of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.