Load access fault identification method and system based on intelligent circuit breaker

Abstract

The invention discloses a load access fault identification method and system based on an intelligent circuit breaker, and the method is characterized in that the method comprises the following steps: deploying a current collection unit in the intelligent circuit breaker, and continuously collecting the current of a load loop corresponding to the intelligent circuit breaker through the current collection unit; continuously calculating the current distortion rate of the load loop by using the collected current of the load loop, and counting current distortion anomalies by using a state counter; and when the counting of the current distortion abnormity exceeds an alarm threshold, a load access fault alarm is sent out. According to the method, the load access fault in the load loop corresponding to the intelligent circuit breaker is effectively analyzed, the arc ignition fault is intelligently recognized through a customized algorithm, automatic opening is achieved, and electricity utilization danger and fire hazard danger are avoided.

Description

Technical Field

[0001] The present invention relates to the field of power systems, and more specifically, to a load access fault identification method and system based on an intelligent circuit breaker. Background Art

[0002] Fault arcs caused by some reasons in the circuit are one of the main causes of electrical fires. At present, electrical fires caused by fault arcs account for about 60% of the total number of electrical fires. The severity of fire accidents caused by fault arcs has attracted attention.

[0003] Electric arc is commonly known as "electric spark" or "sparking". It is essentially a natural phenomenon in which an insulator becomes conductive and emits light and heat after being broken down by voltage. There are many reasons for the occurrence of fault arc. Due to human factors, the insulation layer of the wire is damaged by screws, nails, etc., resulting in insulation failure and causing arc hazards. During the installation of wires, safety risks may arise due to the small bending radius of the wires and improper installation of cables or connectors.

[0004] In the simple electricity use environment of residents, the frequency of arc ignition faults caused by aging and damaged cables is high. Since the old circuit breakers lack the recognition and automatic tripping functions, they cannot cut off the power supply in the first time to avoid greater harm caused by arc ignition. After replacing the old circuit breakers with smart circuit breakers, smart circuit breakers can monitor the user's electricity consumption. However, so far, the utilization rate of smart circuit breakers is not high, and there is a lack of effective and accurate calculation methods to quickly and accurately judge load faults locally at the circuit breaker.

[0005] In addition, the arc spark identification solution requires hardware support for high-precision A / D modules, and the hardware processor must have high-speed big data computing and processing capabilities. It has high requirements for software and hardware design capabilities, and the hardware cost is also high.

[0006] In view of the above problems, there is an urgent need for a load access fault identification method and system based on an intelligent circuit breaker. Summary of the invention

[0007] In order to solve the deficiencies in the prior art, the present invention provides a load access fault identification method and system based on an intelligent circuit breaker.

[0008] The present invention adopts the following technical solution.

[0009] A first aspect of the present invention relates to a load access fault identification method based on an intelligent circuit breaker, characterized in that the method comprises the following steps: deploying a current acquisition unit in the intelligent circuit breaker, and continuously acquiring the current of the load circuit corresponding to the intelligent circuit breaker through the current acquisition unit; continuously calculating the current distortion rate of the load circuit using the acquired current of the load circuit, and using a state counter to count the current distortion anomalies; when the count of the current distortion anomalies exceeds the alarm threshold, issuing a load access fault alarm.

[0010] Preferably, a current acquisition unit is deployed in the intelligent circuit breaker, and the current of the load circuit corresponding to the intelligent circuit breaker is continuously acquired by the current acquisition unit, including: acquiring a current amplitude sequence of the load circuit.

[0011] Preferably, the current distortion rate of the load loop is continuously calculated using the collected current of the load loop, including: performing digital-to-analog conversion on the current amplitude sequence of the load loop to obtain the full-wave current of the load loop; using Fourier transform to decompose the fundamental current from the full-wave current, and using the full-wave current and fundamental current to calculate the current distortion rate of the load loop.

[0012] Preferably, a state counter is used to count the current distortion anomalies, including: pre-setting the open circuit response threshold and the load state threshold of the current distortion rate, and constructing the distortion range of the current distortion anomaly using the open circuit response threshold and the load state threshold; if the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by +1, otherwise the original count is maintained; and the count of the current distortion anomaly at consecutive moments is monitored at intervals of a preset calculation period.

[0013] Preferably, presetting the open circuit response threshold and load state threshold of the current distortion rate includes: setting the load circuit of the intelligent circuit breaker to an open circuit state in advance, and collecting the load circuit current under the open circuit; calculating the current distortion rate curve using the load circuit current under the open circuit, and extracting the current distortion response peak value from the current distortion rate curve; presetting an open circuit response coefficient, multiplying the current distortion response peak value by the open circuit preset coefficient to obtain the open circuit response threshold. c .

[0014] Preferably, the open-circuit response threshold and the load state threshold of the current distortion rate are pre-set, including: monitoring all current distortion rates at continuous moments, extracting the mutation amount of the current distortion rate between any two moments, and if the mutation amount exceeds the mutation threshold, setting a segmentation point between the two moments on the time axis; using the segmentation points to segment the time axis to obtain multiple time periods, extracting the time period with a duration greater than the duration threshold as a typical load state; counting the current distortion rate distribution under each typical load state, and merging multiple time periods with similar distributions into a typical load state; using the current distortion rate distribution, calculating the load state threshold S for each typical load state.

[0015] Preferably, if the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by 1, otherwise the original count is maintained, including: the distortion range is [S, O c ]; if the current distortion rate R at the current moment n n If the current distortion rate R at the current moment n falls within the distortion range, the current distortion abnormality count is +1; n If it falls outside the distortion range, the original count is maintained.

[0016] Preferably, a state counter is used to count current distortion anomalies, including: the interval duration between the current moment n and the next moment n+1 is pre-set; the interval duration is equal to the interval time of each calculation of the current distortion rate by the intelligent circuit breaker; or, the current moment coincides with the moment of the effective value of the current calculated by the intelligent circuit breaker before the last calculation of the current distortion rate.

[0017] A second aspect of the present invention relates to a load access fault identification system based on an intelligent circuit breaker; the system includes a collection unit, a calculation unit, a state counter, and an alarm unit; the collection unit is pre-deployed in the intelligent circuit breaker, and is used to continuously collect the current of the load circuit corresponding to the intelligent circuit breaker through the current collection unit; the calculation unit is used to continuously calculate the current distortion rate of the load circuit using the current of the load circuit collected by the collection unit; the state counter is used to count current distortion anomalies using the current distortion rate of the load circuit collected by the calculation unit; the alarm unit is used to issue a load access fault alarm when the count of current distortion anomalies exceeds the alarm threshold.

[0018] A third aspect of the present invention relates to a terminal, comprising a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method according to the first aspect of the present invention.

[0019] The beneficial effect of the present invention lies in that, compared with the prior art, a load access fault identification method and system based on an intelligent circuit breaker in the present invention collects the current flowing through the intelligent circuit breaker and calculates the current distortion rate, thereby effectively analyzing the load access fault in the load circuit corresponding to the intelligent circuit breaker, and intelligently identifies arc ignition faults through a customized algorithm to achieve automatic tripping, thereby avoiding the occurrence of electrical hazards and fire hazards.

[0020] The beneficial effects of the present invention also include:

[0021] 1. The present invention grasps that the spark phenomenon is actually the fundamental characteristic of the circuit being switched on and off at a relatively high frequency, and uses a relatively simple hardware platform and software to realize circuit spark identification. The method does not require complex and expensive hardware equipment, and does not have high requirements on the calculation speed of the processor and the supporting software algorithm. It has low cost and good effect.

[0022] 2. In the intelligent circuit breaker of the present invention, the sparking phenomenon is actually the essential characteristic of the circuit being switched on and off at a relatively high frequency. By acquiring the current usage in real time and analyzing the changing rules of the current distortion parameters, the function of automatically identifying arc sparking faults is realized.

[0023] 3. The present invention realizes the automatic identification function of arc ignition on the low-computing level hardware platform of the intelligent circuit breaker through a relatively simple software algorithm without increasing the additional product cost, thereby greatly improving the product value of the intelligent circuit breaker and the safety of residents' electricity use. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a flow chart of a method for identifying load access faults based on an intelligent circuit breaker. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer and more accurate, the technical solution of the present invention is described in detail below through multiple specific implementation methods. The embodiments adopted by the present invention are only used to explain the present invention and are not used to limit the content of the present invention.

[0026] Figure 1 The figure is a flow chart of a method for identifying load connection faults based on an intelligent circuit breaker according to the present invention. Figure 1 As shown, the first aspect of the present invention relates to a load access fault identification method based on an intelligent circuit breaker, and the method includes steps 1 to 3.

[0027] Step 1: deploy a current acquisition unit in the intelligent circuit breaker, and continuously acquire the current of the load circuit corresponding to the intelligent circuit breaker through the current acquisition unit.

[0028] The sparking situation of the intelligent circuit breaker under load is as follows Figure 1 As shown. L, N, PE represent the phase lines respectively. The inlet of the intelligent circuit breaker is connected to the L and N phases, and the outlet is connected to the load circuit. The intelligent circuit breaker has an A / D acquisition unit that can collect the actual operating parameters of the current of the L phase.

[0029] A current acquisition unit is deployed in the intelligent circuit breaker, and the current of the load circuit corresponding to the intelligent circuit breaker is continuously acquired by the current acquisition unit, including: acquiring a current amplitude sequence of the load circuit.

[0030] Step 2: continuously calculating the current distortion rate of the load circuit using the collected current of the load circuit, and using a state counter to count the current distortion anomalies.

[0031] The current distortion rate of the load circuit is continuously calculated using the collected current of the load circuit, including: performing digital-to-analog conversion on the current amplitude sequence of the load circuit to obtain the full-wave current of the load circuit; using Fourier transform to decompose the fundamental current from the full-wave current, and using the full-wave current and the fundamental current to calculate the current distortion rate of the load circuit.

[0032] Sparks may occur in the circuit due to aging, damage, etc. The ignition point is the location where the ignition occurs. When the ignition point is located on the load circuit, the corresponding current collection amount on the intelligent circuit breaker will change.

[0033] The operating software of the intelligent circuit breaker collects L-phase current parameters in real time through the hardware A / D acquisition unit, including the fundamental current effective value and the full-wave current effective value. The above two effective values ​​are continuously updated with the collected amount. The intelligent circuit breaker software calculates the total harmonic distortion rate of the current through the fundamental current effective value and the full-wave current effective value, that is:

[0034]

[0035] The calculation results are presented in percentage form.

[0036] Preferably, a state counter is used to count the current distortion anomalies, including: pre-setting the open circuit response threshold and the load state threshold of the current distortion rate, and constructing the distortion range of the current distortion anomaly using the open circuit response threshold and the load state threshold; if the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by +1, otherwise the original count is maintained; and the count of the current distortion anomaly at consecutive moments is monitored at intervals of a preset calculation period.

[0037] In one embodiment, the software sets the variable C as the ignition status counter, which is initialized to 0. The software sets the ignition status counter alarm threshold to THREHOLD, which is initialized to 3. The intelligent circuit breaker monitors the ignition status of the load in real time, and the current distortion rate is R1, R2, R3, R4, ..., R n ,….

[0038] R n is the current distortion rate at the nth calculation, where n is a value from 1 to infinity, indicating an update of the current distortion rate obtained by updating the current effective value calculation as the collected current value changes.

[0039] Presetting the open circuit response threshold and load state threshold of the current distortion rate includes: setting the load circuit of the intelligent circuit breaker to an open circuit state in advance, and collecting the load circuit current under the open circuit; calculating the current distortion rate curve using the load circuit current under the open circuit, and extracting the current distortion response peak value from the current distortion rate curve; presetting the open circuit response coefficient, multiplying the current distortion response peak value by the open circuit preset coefficient to obtain the open circuit response threshold. c .

[0040] In an embodiment, before a certain spark test, the intelligent circuit breaker circuit can be opened, the change curve of the current distortion rate during the opening process can be recorded, and the maximum value can be extracted as the current distortion rate O under the open circuit response. In practice, the current distortion rate O is a relatively large value, and 2% to 5% of O can be taken as a reference for calculating the distortion range.

[0041] The open-circuit response threshold and the load state threshold of the current distortion rate are pre-set, including: monitoring all current distortion rates at continuous moments, extracting the mutation amount of the current distortion rate between any two moments, and if the mutation amount exceeds the mutation threshold, setting a segmentation point between the two moments on the time axis; segmenting the time axis using the segmentation points to obtain multiple time periods, extracting time periods with a duration greater than the duration threshold as typical load states; counting the current distortion rate distribution under each typical load state, and merging multiple time periods with similar distributions into a typical load state; and calculating the load state threshold S for each typical load state using the current distortion rate distribution.

[0042] When the intelligent circuit breaker load is not open and a loop can be formed, the current distortion rate is calculated. In practice, the load connection status is different. Multiple loads under a circuit breaker may be in the connected / unconnected state or in the high power / energy saving state. Therefore, the current distortion rate varies with the load connection. However, by analyzing the load connection changes and truncating the time axis, multiple typical load states are obtained, and the load state threshold is selected for each state.

[0043] When the first abnormal current distortion rate is found, the current distortion rate in the previous period can be analyzed to determine the typical load state corresponding to the previous period, and the load state threshold set S =

[0044] [S1,S2,…,S m ] to extract the most approximate typical load state. m is the number of the typical load state after merging. It is easy to think that each time period corresponds to a current distortion rate distribution, so the distortion rate distributions of multiple time periods are classified to obtain m types. In the period before the first abnormality, the current distortion rate distribution is analyzed, and the approximation with a certain type of distortion rate distribution is calculated, and the typical load state before the abnormality can also be obtained, that is, the set of typical access states of multiple loads in the load circuit corresponding to the circuit breaker.

[0045] Step 3: When the count of abnormal current distortion exceeds the alarm threshold, a load access fault alarm is issued.

[0046] If the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by 1, otherwise the original count is maintained, including: the distortion range is [S, O c ]; if the current distortion rate R at the current moment n n If the current distortion rate R at the current moment n falls within the distortion range, the current distortion abnormality count C+1; n If it falls outside the distortion range, the original count is maintained.

[0047] The above two parameters are used to determine the distortion range, and the number of abnormal current distortion within the range is recorded. Usually, this number is determined for a preset longer period of time, such as 1 hour, 1 day, etc. Once the number of abnormal distortion exceeds the standard within the preset longer period of time, an alarm is issued.

[0048] A state counter is used to count current distortion anomalies, including: the interval between the current moment n and the next moment n+1 is preset; the interval is equal to the interval time of each calculation of the current distortion rate by the intelligent circuit breaker; or, the current moment coincides with the moment of the effective value of the current calculated by the intelligent circuit breaker before the last calculation of the current distortion rate.

[0049] Software in T n+1 -T n It is a time unit, and determines whether the condition of C>=THREHOLD is met. If so, an alarm is triggered.

[0050] Through the present invention, the automatic identification function of arc ignition can be realized on the low-computing level hardware platform of the intelligent circuit breaker through a relatively simple software algorithm without increasing the additional product cost, thereby greatly improving the product value of the intelligent circuit breaker and the safety of residents' electricity use.

[0051] A second aspect of the present invention relates to a load access fault identification system based on an intelligent circuit breaker; the system includes a collection unit, a calculation unit, a state counter, and an alarm unit; the collection unit is pre-deployed in the intelligent circuit breaker, and is used to continuously collect the current of the load circuit corresponding to the intelligent circuit breaker through the current collection unit; the calculation unit is used to continuously calculate the current distortion rate of the load circuit using the current of the load circuit collected by the collection unit; the state counter is used to count current distortion anomalies using the current distortion rate of the load circuit collected by the calculation unit; the alarm unit is used to issue a load access fault alarm when the count of current distortion anomalies exceeds the alarm threshold.

[0052] A third aspect of the present invention relates to a terminal, comprising a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method in the first aspect of the present invention.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention is described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention still include contents that can modify or replace the specific embodiments of the present invention. Any modification or replacement that does not depart from the spirit and scope of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A load access fault identification method based on an intelligent circuit breaker, characterized in that: The method comprises the following steps: A current collection unit is deployed in the intelligent circuit breaker, and the current of the load circuit corresponding to the intelligent circuit breaker is continuously collected by the current collection unit; Continuously calculating the current distortion rate of the load circuit using the collected current of the load circuit, and using a state counter to count the current distortion anomalies; When the count of abnormal current distortion exceeds the alarm threshold, a load access fault alarm is issued.

2. A load access fault identification method based on an intelligent circuit breaker according to claim 1, characterized in that: The step of deploying a current acquisition unit in the intelligent circuit breaker and continuously acquiring the current of the load circuit corresponding to the intelligent circuit breaker through the current acquisition unit includes: A current amplitude sequence of the load loop is collected.

3. A load access fault identification method based on an intelligent circuit breaker according to claim 2, characterized in that: The continuously calculating the current distortion rate of the load circuit by using the collected current of the load circuit includes: Performing digital-to-analog conversion on the current amplitude sequence of the load loop to obtain the full-wave current of the load loop; Fourier transform is used to decompose the fundamental current from the full-wave current, and the current distortion rate of the load circuit is calculated using the full-wave current and the fundamental current.

4. A method for identifying load access faults based on an intelligent circuit breaker according to claim 3, characterized in that: The method of using a state counter to count abnormal current distortion includes: Presetting an open circuit response threshold and a load state threshold of the current distortion rate, and constructing a distortion range of the current distortion abnormality by using the open circuit response threshold and the load state threshold; If the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by 1, otherwise the original count is maintained; The count of the current distortion anomaly at consecutive moments is monitored at intervals of a preset calculation cycle.

5. A load access fault identification method based on an intelligent circuit breaker according to claim 4, characterized in that: The presetting of the open circuit response threshold and the load state threshold of the current distortion rate includes: The load circuit of the intelligent circuit breaker is set to an open circuit state in advance, and the load circuit current under the open circuit is collected; Calculating a current distortion rate curve using the load loop current under the open circuit, and extracting a current distortion response peak value from the current distortion rate curve; The open circuit response coefficient is preset, and the current distortion response peak value is multiplied by the open circuit preset coefficient to obtain the open circuit response threshold value O c .

6. A method for identifying load access faults based on intelligent circuit breaker according to claim 4, characterized in that: The presetting of the open circuit response threshold and the load state threshold of the current distortion rate includes: Monitor all current distortion rates at continuous moments, extract the mutation amount of the current distortion rate between any two moments, and if the mutation amount exceeds the mutation threshold, set a segmentation point between the two moments on the time axis; The time axis is segmented using segmentation points to obtain multiple time periods, and a time period with a duration greater than a duration threshold is extracted as a typical load state; Count the current distortion rate distribution under each typical load state, and combine multiple time periods with similar distribution into a typical load state; The current distortion rate distribution is used to calculate a load state threshold S for each typical load state.

7. A method for identifying load access faults based on an intelligent circuit breaker according to any one of claims 4 to 6, characterized in that: If the current distortion rate at the current moment falls within the distortion range, the count of the current distortion anomaly is increased by 1, otherwise the original count is maintained, including: The distortion range is [S,O c ]; If the current distortion rate R at the current moment n n If it falls within the distortion range, the count of the current distortion anomaly is increased by 1; If the current distortion rate R at the current moment n n If it falls outside the distortion range, the original count is maintained.

8. A method for identifying load access faults based on an intelligent circuit breaker according to claim 7, characterized in that: The method of using a state counter to count abnormal current distortion includes: The interval between the current moment n and the next moment n+1 is preset; The interval time is equal to the interval time of each calculation of the current distortion rate by the intelligent circuit breaker; or, The current moment coincides with the moment when the effective current value was calculated by the intelligent circuit breaker before the current distortion rate was calculated last time.

9. A load access fault identification system based on intelligent circuit breaker; characterized in that: The system includes a collection unit, a calculation unit, a state counter, and an alarm unit; The acquisition unit is pre-deployed in the intelligent circuit breaker and is used to continuously acquire the current of the load circuit corresponding to the intelligent circuit breaker through the current acquisition unit; The calculation unit is used to continuously calculate the current distortion rate of the load circuit using the current of the load circuit collected by the collection unit; The state counter is used to count current distortion anomalies using the current distortion rate of the load circuit collected by the calculation unit; The alarm unit is used to issue a load access failure alarm when the count of abnormal current distortion exceeds an alarm threshold.

10. A terminal comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1-8.

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