CN-122020427-A - Electric isolating switch interlocked with pole-mounted circuit breaker and control method thereof

CN122020427ACN 122020427 ACN122020427 ACN 122020427ACN-122020427-A

Abstract

The invention relates to the technical field of electric switches, in particular to an electric isolating switch interlocked with a pole-mounted circuit breaker and a control method thereof, comprising the steps of obtaining standard coil current data, actual coil current data, main loop three-phase current data, power supply side voltage data and load side voltage data and preprocessing the data; determining time dividing points by utilizing wave crest and wave trough distribution characteristics to divide phase intervals, obtaining health coefficients of the pole-mounted circuit breakers through phase interval similarity analysis, calculating electric isolation coefficients by combining current level differences of a main loop and voltage amplitude and phase differences of two sides, and performing grading interlocking control on the electric isolation switches based on the health coefficients and the electric isolation coefficients. According to the invention, a two-dimensional evaluation system of the mechanism health pre-judgment and the electrical isolation hard criterion is constructed through multi-source data fusion, so that the safety and reliability of the operation of the distribution network are improved through a grading interlocking control strategy.

Inventors

Ni Peirong
ZHENG XIANGFEI
Zhu Suimu

Assignees

华毅达电力科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (10)

1. A method of controlling an electrical disconnector interlocked with a pole-mounted circuit breaker, the method comprising the steps of: Standard coil current data, actual coil current data, main loop three-phase current data, power supply side voltage data and load side voltage data are obtained, and data preprocessing is carried out; Determining a plurality of time division points respectively belonging to the standard coil current data and the actual coil current data by utilizing the distribution conditions of peaks and troughs of the standard coil current data and the actual coil current data in different time ranges, and determining a plurality of phase intervals respectively corresponding to the standard coil current data and the actual coil current data through the time division points, wherein the number of the phase intervals respectively corresponding to the standard coil current data and the actual coil current data is the same; The method comprises the steps of obtaining the health coefficient of the pole-mounted circuit breaker by carrying out data similarity condition analysis on actual coil current data and standard coil current data between phase intervals with the same ordinal number; Calculating an electrical isolation coefficient by combining current level differences of three-phase current data of the main loop in different time ranges and difference characteristics corresponding to voltages and voltage phases at different positions respectively; and performing grading interlocking control on the electric isolating switch based on the health coefficient and the electric isolating coefficient of the pole-mounted circuit breaker.
2. The control method of an electric disconnector interlocked with a pole-mounted circuit breaker according to claim 1, characterized in that the specific acquisition method of the phase interval is: For standard coil current data, acquiring a time point when a controller sends a closing command, and recording the time point as a first time point; acquiring a starting time window based on a first time point and a first fixed value, acquiring a maximum peak of standard coil current data in the starting time window, and recording a time point corresponding to the maximum peak as a second time point; acquiring an action time window based on a second time point and a second fixed value, acquiring the minimum trough of the standard coil current data in the action time window, and recording a time point corresponding to the minimum trough as a third time point; Acquiring an execution time window based on a third time point and a third fixed value, acquiring a maximum current value of standard coil current data in the execution time window, and recording a time point corresponding to the maximum current value as a fourth time point; Using the first time point as a starting point, performing traversal search on current values in the standard coil current data, and continuously performing When the current values are smaller than the preset current threshold value, will be A time point corresponding to the last current value of the current values is taken as a fifth time point, wherein Is a preset quantity parameter; the first, second, third, fourth and fifth time points are collectively called as time dividing points, the section formed by the adjacent time dividing points is used as a phase section to obtain a plurality of phase sections of the standard coil current data, and the same is done to obtain a plurality of phase sections of the actual coil current data.
3. The control method of an electric disconnecting switch interlocked with a pole-mounted circuit breaker according to claim 2, wherein the specific obtaining method of the health coefficient of the pole-mounted circuit breaker is as follows: Presetting corresponding phase weights for each phase interval, so as to carry out weighted fusion on the similarity between the standard coil current data and the actual coil current data in each phase interval, and obtaining a global similarity coefficient between the standard coil current data and the actual coil current data; Calculating a first deviation coefficient and a second deviation coefficient respectively by using difference characteristics respectively formed between the standard coil current data and the actual coil current data with respect to the time division points and the corresponding current values of the different time division points; And presetting coefficient weights for the global similarity coefficient, the first deviation coefficient and the second deviation coefficient respectively, so that the global similarity coefficient, the first deviation coefficient and the second deviation coefficient are subjected to weighted fusion, and the health coefficient of the pole-mounted circuit breaker is obtained.
4. A control method of an electric disconnector interlocked with a pole-mounted circuit breaker according to claim 3, characterized in that the specific acquisition method of the global similarity coefficient is as follows: Acquiring a DTW distance between corresponding data segments in any phase interval of the same ordinal number between standard coil current data and actual coil current data, and calculating a similarity factor of the standard coil current data and the actual coil current data in the corresponding phase interval according to the DTW distance, wherein the DTW distance and the similarity factor are in negative correlation; And combining the phase weights of all the phase intervals and the similarity factors under the corresponding phase intervals, and obtaining the global similarity coefficient between the standard coil current data and the actual coil current data by a weighted average method.
5. A control method of an electric disconnector interlocked with a pole-mounted circuit breaker according to claim 3, characterized in that the specific acquisition method of the first deviation coefficient is: And respectively recording the current values corresponding to the second, third and fourth time points as a peak starting current value, a trough current value and a stable saturated current, and combining the difference conditions of the standard coil current data and the actual coil current data respectively about the peak starting current value, the trough current value and the stable saturated current to obtain a first deviation coefficient.
6. A control method of an electric disconnector interlocked with a pole-mounted circuit breaker according to claim 3, characterized in that the specific acquisition method of the second deviation coefficient is: The standard coil current data and the actual coil current data are collectively called as coil current data, and a time interval value between a first time point and a fifth time point of the coil current data is recorded as a duration parameter of the corresponding coil current data; And combining the difference conditions of the standard coil current data and the actual coil current data respectively related to the second, third and fourth time points and the time length parameters to obtain a second deviation coefficient.
7. The control method of an electric isolating switch interlocked with a pole-mounted circuit breaker according to claim 1, wherein the specific obtaining method of the electric isolating coefficient is as follows: Determining a main loop current identification window and a working current window based on time dividing points, and calculating a brake-off current attenuation rate through current level differences of three-phase current data of the main loop in the main loop current identification window and the working current window respectively; Calculating a voltage decoupling rate according to the difference conditions of the voltage level and the voltage phase level of the power supply side voltage data and the load side voltage data after the opening; the electrical isolation coefficient is determined based on the relative magnitude between the opening current decay rate and the voltage decoupling rate.
8. The method for controlling an electric disconnecting switch interlocked with a pole-mounted circuit breaker according to claim 7, wherein the specific obtaining method of the voltage decoupling rate is as follows: acquiring power supply side voltage data and load side voltage data after opening, respectively calculating a power supply side voltage effective value and a load side voltage effective value, and extracting a power supply side voltage phase and a load side voltage phase; The voltage decoupling rate is calculated by combining the amplitude difference between the effective value of the power supply side voltage and the effective value of the load side voltage and the phase difference between the phase of the power supply side voltage and the phase of the load side voltage.
9. The method for controlling the electric disconnecting switch interlocked with the pole-mounted circuit breaker according to claim 1, wherein the step-by-step interlocking control of the electric disconnecting switch based on the health coefficient and the electric disconnecting coefficient of the pole-mounted circuit breaker comprises the following specific steps: presetting a plurality of grade thresholds, and comparing the health coefficient and the electrical isolation coefficient of the pole-mounted circuit breaker with the corresponding grade thresholds respectively to determine an interlocking control grade; matching corresponding operation authority control rules according to the determined interlocking control level, wherein the operation authority control rules comprise opening, limiting or locking of operation authorities, and corresponding early warning information generation and reporting; When the interlocking control level is the highest safety level, opening all operation authorities of the electric isolating switch; When the interlocking control level is the lowest safety level, triggering hardware hard locking, physically cutting off the operation power supply of the electric isolating switch, and generating fault alarm information.
10. An electric disconnector interlocked with a pole-mounted circuit breaker, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, realizes the steps of a method for controlling an electric disconnector interlocked with a pole-mounted circuit breaker according to any one of claims 1-9.

Description

Electric isolating switch interlocked with pole-mounted circuit breaker and control method thereof Technical Field The invention relates to the technical field of electric switches, in particular to an electric isolating switch interlocked with a pole-mounted circuit breaker and a control method thereof. Background In the current 10kV urban and rural distribution network, the combined complete equipment of the pole-mounted circuit breaker and the electric isolating switch becomes core equipment for distribution network automation, line segmentation and fault isolation, and in order to ensure distribution network maintenance safety and operation standardization, a forced interlocking design of the circuit breaker and the isolating switch is generally adopted in the industry, and the core operation principle is that the isolating switch can be operated after the circuit breaker is switched in place. Most of the existing interlocking schemes take position contact signals output by an auxiliary switch of a circuit breaker as unique interlocking criteria, and an electric locking loop which is matched with the existing interlocking schemes is simple in structure, low in cost and convenient to wire, so that the existing interlocking schemes become general standard scheme in the industry, and are widely applied to distribution network column switch equipment in the national range. In the existing general interlocking scheme, the criterion of the general interlocking scheme only depends on the position signal of the auxiliary contact of the circuit breaker, and cannot reflect the real electric on-off state and the mechanism health state. When the main contact fusion welding, arc extinguishing chamber breakdown false brake opening, or auxiliary contact adhesion, connecting rod falling and other faults occur, the system can misjudge that the brake opening is in place, so that the malignant accident of the on-load operation isolating switch is caused. Meanwhile, hidden faults such as coil aging, iron core blocking and the like cannot be identified, early warning cannot be performed in advance, misoperation locking or misoperation can be easily caused under the strong electromagnetic interference environment, and the unattended high-safety and high-reliability operation requirements of the distribution network are difficult to meet. Disclosure of Invention The invention provides an electric disconnecting switch interlocked with a pole-mounted circuit breaker and a control method thereof, which aim to solve the existing problems that the existing general interlocking scheme depends on auxiliary contact signals, cannot reflect the actual electric state and the mechanism health state of the circuit breaker, has misjudgment risks such as fusion welding, false brake opening and contact adhesion, cannot early warn hidden faults, has insufficient anti-interference capability and is difficult to meet the high-safety operation requirement. The invention relates to an electric isolating switch interlocked with a pole-mounted circuit breaker and a control method thereof, which adopts the following technical scheme: one embodiment of the present invention provides a control method of an electric disconnecting switch interlocked with a pole-mounted circuit breaker, the method comprising the steps of: Standard coil current data, actual coil current data, main loop three-phase current data, power supply side voltage data and load side voltage data are obtained, and data preprocessing is carried out; Determining a plurality of time division points respectively belonging to the standard coil current data and the actual coil current data by utilizing the distribution conditions of peaks and troughs of the standard coil current data and the actual coil current data in different time ranges, and determining a plurality of phase intervals respectively corresponding to the standard coil current data and the actual coil current data through the time division points, wherein the number of the phase intervals respectively corresponding to the standard coil current data and the actual coil current data is the same; The method comprises the steps of obtaining the health coefficient of the pole-mounted circuit breaker by carrying out data similarity condition analysis on actual coil current data and standard coil current data between phase intervals with the same ordinal number; Calculating an electrical isolation coefficient by combining current level differences of three-phase current data of the main loop in different time ranges and difference characteristics corresponding to voltages and voltage phases at different positions respectively; and performing grading interlocking control on the electric isolating switch based on the health coefficient and the electric isolating coefficient of the pole-mounted circuit breaker. Preferably, the specific obtaining method of the stage interval is as follows: For standard coil current data, acquiring a t