CN-122020947-A - Circuit breaker loop resistance operation monitoring and evaluating method based on improved whale optimization algorithm

CN122020947ACN 122020947 ACN122020947 ACN 122020947ACN-122020947-A

Abstract

The invention discloses a circuit breaker loop resistance operation monitoring and evaluating method based on an improved whale optimization algorithm, which comprises the following steps of S1, constructing a resistance state evaluating frame fused with multidimensional operation data, S2, converting a problem of solving the resistance of a switching device into a linear equation set for solving a current working condition, S3, converting the solving of the linear equation set for the current working condition into a voltage working condition objective function capable of eliminating the pathological influence of the linear equation set for solving the current working condition, S4, adopting the improved whale optimization algorithm which introduces a dynamic reverse learning strategy and a self-adaptive weight factor to solve the voltage working condition objective function, obtaining a loop resistance dynamic value, S5, adopting a time window cycle dynamic repeating step S4 to obtain a loop resistance change curve, and judging a long-term stable state and an abnormal fault condition of the loop resistance. The fault early warning accuracy rate of the invention reaches 94.7%, and the invention provides key technical support for the whole life cycle management of the intelligent substation breaker and has important engineering application value.

Inventors

ZHAO KAI
SUN HAIWEN
JIANG HAITAO
LI KANGWEI
MA XIANGGUO
WANG YUHUAI
Feng kunlun
LI LUXIN
LIU ZHENG
YANG GENG

Assignees

宁夏送变电工程有限公司

Dates

Publication Date: 20260512
Application Date: 20251201

Claims (10)

1. A circuit breaker loop resistance operation monitoring and evaluating method based on an improved whale optimization algorithm is characterized by comprising the following steps: s1, constructing a resistance state evaluation frame fused with multidimensional operation data based on topological structure characteristics of a circuit breaker loop; s2, converting the problem of solving the resistance of the switching equipment into a linear equation set for solving the current working condition under a resistance state evaluation framework; s3, solving a linear equation set of current working conditions into a voltage working condition objective function capable of eliminating the pathological influence of the linear equation set; s4, solving a voltage working condition objective function by adopting an improved whale optimization algorithm introducing a dynamic reverse learning strategy and a self-adaptive weight factor, and obtaining a loop resistance dynamic value when the voltage working condition objective function obtains an optimal value; S5, repeating the step S4 by adopting time window cyclic dynamic state to obtain a loop resistance change curve, and judging the long-term stable state and abnormal fault condition of the loop resistance.
2. The method for monitoring and evaluating the resistance operation of the circuit breaker based on the improved whale optimization algorithm as claimed in claim 1, wherein the circuit breaker in the step S1 adopts a 3/2 wiring mode.
3. The method for monitoring and evaluating the circuit breaker loop resistance based on the improved whale optimization algorithm according to claim 1 or 2, wherein the process of converting the problem of solving the resistance of the switching device into the linear equation set for solving the current working condition under the resistance state evaluation framework in the step S2 is that assuming that m branches containing three switches are provided in a switching station, n branches containing two switches are provided, the current flowing through each switch is measured at a certain moment: 、、、...、、 The resistance of each switch is: 、、、...、、 And (3) the following steps: voltage across branch 1: (1) voltage across branch 2: (2) voltage across the mth branch: (3) voltage across the (m+n) th branch: (4) Neglecting the pressure drop over the bus: (5) The formula (6) is obtained from the formula (5), (6) Namely: (7) Rewriting formula (7) into a matrix form: (8) The homogeneous linear equation set provided by equation (8) cannot find the special solution, but can only find the ratio between the resistances of the switch loops, assuming Is the smallest resistance, then it is chosen as the reference resistance, i.e Obtaining a current working condition linear equation set shown in the formula (9): (9) In the formula (9), the amino acid sequence of the compound, Representation of And (3) with Is called as the ratio of Is a switching resistor.
4. The method for monitoring and evaluating circuit breaker loop resistance operation based on improved whale optimization algorithm as claimed in claim 3, wherein the process of converting the solution of the current condition linear equation set into the voltage condition objective function capable of eliminating the pathological influence in the step S3 is expressed as follows: (10) in the formula (10), the amino acid sequence of the compound, Is a current working condition coefficient matrix, In the form of a matrix of resistance vectors, Obtaining loop resistance values of all switching devices by solving a linear equation set of current working conditions as a current vector matrix; current operating mode coefficient matrix Is one A row(s), A matrix of columns, the elements of which are represented as The right hand side of the equation is written as It is one Matrix of row and column 1, each shunt voltage 、 For the absolute value of each shunt voltage, the voltage operating mode objective function is obtained as follows: (14) in the formula (14), the amino acid sequence of the compound, Is an objective function of the voltage operating condition, Represents the optimal variables to be used in the process of optimizing, =1、2、3、...、 , The total loop resistance.
5. The method for monitoring and evaluating circuit breaker loop resistance operation based on the improved whale optimization algorithm according to claim 1, wherein the step of improving the whale optimization algorithm in the step S4 is as follows: S41, initializing a parent population, randomly generating a group of initial solutions as the parent population, calculating the fitness value of each individual, sorting the population according to the fitness value, and selecting the individuals with better fitness as excellent individuals; S42, selecting and shifting, namely selecting individuals from the parent population according to the selection probability to generate a child population, and directly bringing the most excellent parent individuals into the child population to ensure the inheritance of the child to the parent excellent individuals; s43, introducing a dynamic reverse learning strategy, selecting two individuals from parent individuals to perform reverse learning, generating new offspring individuals, and further optimizing the diversity of the population; s44, introducing an adaptive weight factor to perform dynamic balance of global search and local convergence, and obtaining a loop resistance dynamic value when the current working condition objective function obtains an optimal value.
6. The method for monitoring and evaluating circuit breaker loop resistance operation based on improved whale optimization algorithm as claimed in claim 5, wherein the probability of selection in step S42 The calculation formula of (2) is as follows: (15) In the formula (15), the amino acid sequence of the compound, Is the first The fitness value of the individual person, Is the population scale.
7. The method for monitoring and evaluating circuit breaker loop resistance operation based on improved whale optimization algorithm as claimed in claim 5, wherein the dynamic reverse learning strategy in step S43 is characterized in that a neighborhood is set at a new position of the iterative optimization, the position is compared with random neighborhood coordinates in the same dimension, and coordinate positions of fitness are selected for the next iterative optimization; Each individual in the search space selects a candidate solution in the neighborhood of the individual to compare and optimize, and in a dynamic reverse learning strategy, position iteration is generated through the learning of the last position and the neighbor position, wherein the calculation formula of the regional radius of the neighborhood of the individual is as follows: (17) Wherein, the Is the first Second iteration (a) The neighborhood radius of the individual is determined, Is the first Second iteration (a) The location of the individual(s), Is the first Candidate positions for the next iteration, in Locations within the neighborhood radius may be candidates for dynamic reverse learning strategy reference.
8. The method for monitoring and evaluating circuit breaker loop resistance operation based on improved whale optimization algorithm as claimed in claim 7, wherein the location update formula in the dynamic reverse learning strategy in step S43 is as follows: (18) In the formula (18), the amino acid sequence of the compound, As the current optimal position of the object to be processed, For the reverse neighbor location, For the current selection of the location of the individual, Is the learning rate.
9. The method for monitoring and evaluating circuit breaker loop resistance operation based on improved whale optimization algorithm as claimed in claim 5, wherein the calculation formula of the adaptive weight factor in the step S44 is as follows: (19) in the formula (19), the amino acid sequence of the compound, For the current number of iterations, Is the total iteration number; the mathematical definition of the self-adaptive weight factors is used for judging whether an individual reaches a distribution threshold or not, and the formula is as follows: (20) In the formula (20), the amino acid sequence of the compound, Is the threshold value of the aggregate-scatter, Is the maximum value of fitness of all individuals in the whole current population, Is the minimum of fitness of all individuals in the current whole population, Is a feature of the location of an individual in the search space, such as its distance from the group's center point, an event trigger indicator When the total distribution is larger than 0, the individual distribution is higher, the deviation group is more, and global searching action is adopted; principal event trigger index Individuals with less than 0 have lower distribution, less deviation from the population, and take local convergence actions.
10. The circuit breaker loop resistance operation monitoring and evaluating method based on the improved whale optimization algorithm, which is characterized in that the circuit breaker loop resistance operation monitoring and evaluating method has a function of predicting the deterioration trend of the circuit breaker loop resistance, and the change trend of future resistance is predicted through the comparative analysis of historical data and real-time data, and early warning signals are sent in advance; the degradation trend prediction adopts a time sequence analysis method, and a prediction model is as follows: (21) in the formula (21), the amino acid sequence of the amino acid, In order to predict the resistance value of the resistor, Is an initial resistance value, , 、、 Is a model parameter; the setting of the early warning threshold is based on statistical analysis of historical data, and the early warning formula is as follows: (22) in the formula (22), the amino acid sequence of the compound, Is an early warning threshold.

Description

Circuit breaker loop resistance operation monitoring and evaluating method based on improved whale optimization algorithm Technical Field The invention belongs to the technical field of electric power, and particularly relates to a circuit breaker loop resistance operation monitoring and evaluating method based on an improved whale optimization algorithm. Background The circuit breaker and the isolating switch are used as primary equipment in a transformer substation and are used for carrying important tasks of controlling circuit switching and protecting normal operation of equipment. The state monitoring and evaluation of the circuit breaker and the isolating switch are key to ensuring the safe and reliable operation of equipment, and are also necessary routes for improving the reliability of power supply and distribution. The switching equipment state evaluation model is built to evaluate the working condition of the switching equipment, so that basis can be provided for operation maintenance personnel and experts to monitor the switching state and timely find potential safety hazards, the blindness and maintenance times of power failure maintenance of the switching equipment are reduced, the maintenance period is expanded to the greatest extent, the operation rate of the switching equipment is improved, and the economic benefit of an electric power operation department and the reliability of user electricity are improved. On the one hand, the increase of the resistance value of the switch can increase the heating of the switch, and the service life of the equipment is influenced. On the other hand, the difference in the resistance of the branch switches in the substation also affects the current distribution in the substation. Therefore, calculating the resistance of each switch in the substation is an important part of evaluating the operating state of the switchgear. The switching equipment with abnormal resistance value is found in time, so that the switching equipment has very important significance for eliminating accident potential and guaranteeing the safety and stability of a power system. Compared with the equipment such as a transformer, a generator, a capacitor and the like, the circuit breaker state monitoring technology starts later. The state monitoring technology of the circuit breaker does not gradually develop until 90 s later. In the 90 s, the united states and japan begin to study the state monitoring of the circuit breaker, american students first give the relationship between the service life and the breaking current of the circuit breaker, put forward the concept of the electrical life of an arcing contact, and the concept of the integrity monitoring of the full-condition tripping and closing loop is also synchronously put forward, and the study work is mainly carried out around the state maintenance of the circuit breaker. With the deep research, the breaker state monitoring devices are produced successively. As early as 1992, ALSTOM used Control and monitoring system for the first time on 500KV circuit breakers in the Grizzly substation in the united states, and in the following years this set of devices was widely used on 500KV high voltage circuit breaker devices of model FX32D in the Hammer substation, canada. Later, ALSTHOM developed a more advanced CBWatch-1 system in 1999 to 2000, and an important breakthrough of the CBWatch-1 system is that it can predict the pressure change trend of SF6 gas and give low-pressure alarm. The development of a large-scale expert fault diagnosis system is proceeding, and a breaker fault detection system based on a neural network and a fuzzy theory begins to appear. The research of the state monitoring of the domestic high-voltage circuit breaker is earlier, the Jilin electric bureau in 1992 stands on the 'monitoring of the mechanical characteristics of the circuit breaker' and 'GIS partial discharge ultrahigh frequency on-line monitoring', and a CBA-1 high-voltage circuit breaker parameter measurement analysis system is developed in a university of Qinghua in 1995, and can monitor on-off current, travel curve and vibration signals. The mechanical parameter monitor of the high-voltage circuit breaker, which appears in China for years, can monitor various operation parameters of the circuit breaker and prevent faults of the circuit breaker. Studies of signal analysis and diagnostic methods based on neural networks, wavelet analysis, fuzzy theory have been started for experiments. The following problems exist in the existing circuit breaker loop resistance monitoring method: 1. The traditional monitoring method is difficult to realize online and real-time monitoring, the dynamic change of the circuit resistance of the circuit breaker cannot be reflected in time, and the requirement of the intelligent substation on real-time evaluation of the equipment state is difficult to be met. 2. When solving a circuit resistance evaluation model of a circuit