Distribution network fault judgment method and system based on bus voltage abrupt change

Abstract

The invention relates to the technical field of power distribution networks, and discloses a bus voltage abrupt change-based distribution network fault judgment method and system, and the method comprises the steps: obtaining a voltage abrupt change value, setting a voltage abrupt change value threshold value, and carrying out the comparison processing. According to the mode provided by the invention, faults can be quickly isolated, system parameters can be recovered, the safety and stability of a power grid are ensured, the sensitivity of the distribution network can be reduced, the fluctuation of the distribution network lower than a voltage sudden change threshold value cannot be overhauled, and the normal work of the distribution network is not influenced. Normal bus voltage abrupt change fluctuation can be understood. If all bus voltage abrupt change fluctuations are concerned excessively, the work of a distribution network is affected, and the energy of maintenance personnel is consumed excessively.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network, and in particular to a distribution network fault judgment method and system based on bus voltage mutation. Background Art

[0002] The bus voltage mutation and distribution network fault have the following relationship:

[0003] 1. Sudden changes in bus voltage may cause distribution network failures. On the one hand, excessively high or low bus voltages may affect the normal operation of distribution equipment; on the other hand, voltage fluctuations may cause malfunction or damage to distribution network equipment such as circuit breakers and transformers.

[0004] 2. Distribution network faults may have a reverse impact on bus voltage. On the one hand, a distribution network fault may cause a sharp increase in current, resulting in a rapid drop in bus voltage; on the other hand, a serious fault may cause the protection device to operate, cutting off the line or equipment, further affecting the bus voltage.

[0005] There are many reasons for bus voltage mutation. At present, when bus voltage mutation occurs, the troubleshooting of distribution network faults needs to comprehensively consider multiple reasons and conduct detailed troubleshooting. When troubleshooting, it will not only affect the normal operation of the distribution network itself, but also require more troublesome troubleshooting work. Summary of the invention

[0006] In view of the problems existing in the above-mentioned prior art, the object of the present invention is to provide a distribution network fault judgment method and system based on bus voltage mutation, so as to optimize the distribution network fault troubleshooting method when the bus voltage mutation occurs.

[0007] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a distribution network fault judgment method based on bus voltage mutation, comprising the following steps: a first step, obtaining the instantaneous value of the bus voltage mutation, subtracting the reference value of the bus voltage from the instantaneous value and performing absolute value processing to obtain the voltage mutation value, and the voltage mutation value is used as a reference for subsequent judgment; a second step, setting a voltage mutation value threshold value based on the comprehensive distribution network operation characteristics, operation standards and the bearing capacity of key power-consuming equipment, and the bus voltage mutation fluctuation that does not exceed the voltage mutation value threshold value does not affect the continuous use of the distribution network; a third step, using the voltage mutation value to compare with the voltage mutation value threshold value, if the voltage mutation value is less than or equal to the voltage mutation value threshold value, it indicates that the bus voltage fluctuation is within an acceptable range, the system does not intervene, and continues to monitor normally; if the voltage mutation value is greater than the voltage mutation value threshold value, the fault type of the voltage mutation is judged, and different processing is performed according to the fault type.

[0008] In some embodiments, the bus voltage mutation fault types include sudden drop and sudden increase. If the difference between the instantaneous value of the bus voltage and the reference value is a positive number, it indicates that the instantaneous value of the bus voltage is greater than the reference value, and the mutation type is a sudden increase; if the difference between the instantaneous value of the bus voltage and the reference value is a negative value, it indicates that the instantaneous value of the bus voltage is less than the reference value, and the mutation type is a sudden drop.

[0009] In some embodiments, when the voltage mutation value is greater than the voltage mutation value threshold, a mutation range threshold is set, the voltage mutation value is divided by the reference value to obtain a mutation range value, the mutation range value is compared with the mutation range threshold, and different responses are obtained based on the comparison result.

[0010] In some embodiments, if the mutation range value is less than the mutation range threshold, it indicates that the range of the bus voltage mutation is small; if the mutation range value falls within the mutation range threshold, it indicates that the range of the bus voltage mutation is medium; if the mutation range value is greater than the mutation range threshold, it indicates that the range of the bus voltage mutation is large; among them, for a bus voltage sudden increase with a small mutation range, continuously check the bus voltage or reactive compensation equipment parameters; for a bus voltage sudden increase with a medium mutation range, adjust the reactive compensation equipment action mechanism; for a bus voltage sudden increase with a large mutation range, use a tap to reduce the bus voltage; for a bus voltage sudden drop with a small mutation range, continue monitoring; for a bus voltage sudden drop with a medium mutation range, add reactive compensation equipment; for a bus voltage sudden drop with a large mutation range, check for short circuits and isolate faulty lines.

[0011] In some embodiments, when the voltage mutation value is less than or equal to the voltage mutation value threshold, a proximity threshold is set, the proximity threshold is less than the voltage mutation value threshold, the voltage mutation value is compared with the proximity threshold, and different responses are obtained according to the comparison result.

[0012] In some embodiments, if the voltage mutation value is less than the approach threshold, the monitoring system continues monitoring normally; if the voltage mutation value is greater than or equal to the approach threshold, the bus voltage monitoring frequency is increased.

[0013] In some embodiments, there are two ways to increase the bus voltage monitoring frequency. One is to shorten the original monitoring time interval, which is proportionally shortened according to the degree to which the voltage mutation value is close to the voltage mutation value threshold; the other is to keep the monitoring period unchanged and increase the number of monitoring times within one monitoring period, which is proportionally increased according to the degree to which the voltage mutation value is close to the voltage mutation value threshold.

[0014] In some embodiments, a cycle number limit value for increasing the monitoring frequency is set. When the voltage mutation value of the bus voltage is less than or equal to the voltage mutation value threshold but greater than or equal to the threshold, the monitoring mode of the monitoring system is dynamically adjusted to mode one or mode two. Thereafter, if the voltage mutation value threshold does not exceed the voltage mutation value threshold after continuously passing through the monitoring cycle of the cycle number limit value, the system determines that the current voltage mutation value change trend is stable, and the monitoring system restores the original monitoring mode.

[0015] The present invention also provides the following technical solutions:

[0016] The present invention further provides a distribution network fault judgment system based on bus voltage mutation, including: a reference acquisition module: which is used to obtain the instantaneous value of the bus voltage mutation, and the instantaneous value is subtracted from the reference value of the bus voltage and then processed as an absolute value to obtain the voltage mutation value; a threshold setting module: which is used to set the voltage mutation value threshold based on the comprehensive distribution network operation characteristics, operation standards and the bearing capacity of key power-consuming equipment; a comparison and response module: which is used to compare the voltage mutation value with the voltage mutation value threshold. If the voltage mutation value is less than or equal to the voltage mutation value threshold, it indicates that the bus voltage fluctuation is within an acceptable range, and the system does not intervene and continues to monitor normally; if the voltage mutation value is greater than the voltage mutation value threshold, the fault type of the voltage mutation is judged, and different processing is performed according to the fault type.

[0017] The present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the above-mentioned distribution network fault judgment method based on bus voltage mutation.

[0018] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0019] First, in the present invention, a voltage mutation value threshold is set based on the operation characteristics of the distribution network, and the voltage mutation value of the bus voltage is compared with the voltage mutation value threshold. If it is less than or equal to the voltage mutation value threshold, it indicates that the fluctuation of the bus voltage is small and within an acceptable range. At this time, no additional intervention is required, and the system operates normally and is continuously monitored. If it is greater than the voltage mutation value threshold, it indicates that the fluctuation of the bus voltage is large. At this time, it is necessary to judge the type of bus voltage mutation, that is, whether the mutation is a sudden increase or a sudden drop, and then define the sudden increase and sudden drop into three different fluctuation degrees of large, medium and small. In this way, different distribution network fault response and processing methods can be made in a targeted manner according to different fluctuation degrees and fluctuation types.

[0020] Secondly, in the present invention, when the voltage mutation value is less than or equal to the voltage mutation value threshold, a proximity threshold is set to compare with the voltage mutation value. For voltage mutation values ​​less than the proximity threshold, it means that they are far away from the voltage mutation value threshold and no additional attention is required; and for voltage mutation values ​​greater than or equal to the proximity threshold, it means that they are close to the voltage mutation value threshold and the possibility of exceeding the voltage mutation value threshold is high. Therefore, for this situation, the monitoring system makes a dynamic adjustment method to increase the monitoring frequency so that it can be discovered and processed in time when the voltage mutation value exceeds the voltage mutation value threshold.

[0021] Thirdly, in the present invention, certain restrictions are imposed on the dynamic adjustment method of increasing the monitoring frequency, and a cycle number limit value for increasing the monitoring frequency is set. If after the monitoring frequency is dynamically increased, the voltage mutation value does not exceed the voltage mutation value threshold after continuously passing through the monitoring cycle of the cycle number limit value, then at this time, in order to avoid long-term pressure on the monitoring system, the monitoring system can restore the original monitoring method. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the module flow of the present invention;

[0023] Figure 2 It is a schematic diagram of the logical structure of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0026] The present invention provides a distribution network fault judgment method based on bus voltage mutation, such as Figure 1 and Figure 2 As shown, the following steps are included:

[0027] Step 1: When the bus voltage suddenly changes, the value of the bus voltage sudden change is obtained through a high-precision sensor or voltage transformer, recorded as the voltage sudden change value, and the voltage sudden change value is recorded as a basis for subsequent judgment. The voltage sudden change value is the absolute value of the difference between the instantaneous value of the bus voltage, that is, the value of the bus voltage sudden change obtained by the sensor and the reference value, where the reference value is the rated voltage of the bus or the average voltage over a period of time. In addition, the long-term slow changes in bus voltage, such as trend changes caused by load fluctuations, need to be distinguished from instantaneous sudden changes, and interference can be further eliminated through filtering algorithms.

[0028] Step 2: Set the voltage mutation threshold value according to the power grid situation. The voltage mutation threshold value is the maximum fluctuation that the power grid system can accept for normal operation. It is set according to the operating characteristics and standards of the power grid. In addition, the setting also needs to comprehensively consider the bearing capacity of key power-consuming equipment to ensure that power grid fluctuations will not affect the safe operation of the equipment. After the set voltage mutation threshold value is determined, as long as the fluctuation does not exceed the voltage mutation threshold value, the impact on the power grid does not affect its normal operation and it can continue to be used normally.

[0029] Step three, compare the voltage mutation value with the voltage mutation value threshold, and obtain different responses based on the comparison results. If the voltage mutation value is less than or equal to the voltage mutation value threshold, it means that the fluctuation is within an acceptable range and does not affect the normal operation of the power grid system. If the voltage mutation value is greater than the voltage mutation value threshold, it means that the fluctuation has exceeded the limit. At this time, it is necessary to first determine whether the voltage mutation is a sudden drop or a sudden increase, and then take different response measures according to the type of voltage mutation. The core of this step is to quickly determine the power grid state and take targeted measures by comparing the voltage mutation value with the voltage mutation value threshold. If the voltage mutation value is less than or equal to the voltage mutation value threshold, no intervention is required, and the system can continue to work normally and continue to monitor; if it is greater than the voltage mutation value threshold, it is necessary to determine the fault type so that corresponding treatment measures can be taken. In this way, the fault can be quickly isolated and the system parameters can be restored to ensure the safety and stability of the power grid. In addition, this fault judgment method can reduce the sensitivity of the distribution network, so that the distribution network fluctuations below the voltage mutation value threshold will not be over-maintained. As long as it does not affect the normal operation of the distribution network, the normal bus voltage mutation fluctuations are understandable. If all bus voltage mutation fluctuations are overly concerned, it will not only affect the work of the distribution network, but also consume too much energy of maintenance personnel.

[0030] Whether the bus voltage mutation is a sudden drop or a sudden increase is determined based on the difference between the instantaneous value of the bus voltage obtained by the sensor and the reference value. If the difference between the instantaneous value of the bus voltage and the reference value is a positive number, it indicates that the instantaneous value of the bus voltage is greater than the reference value. In this case, under the premise that the bus voltage has already changed suddenly, the type of this mutation is a sudden increase. If the difference between the instantaneous value of the bus voltage and the reference value is a negative value, it indicates that the instantaneous value of the bus voltage is less than the reference value. In this case, under the premise that the bus voltage has already changed suddenly, the type of this mutation is a sudden drop. For example, assuming that the instantaneous voltage of the bus obtained by the sensor is U1 and the reference value is U2, the absolute value of the difference between the two can be expressed as ΔU. If ΔU>0, it means that the current instantaneous value of the bus voltage is greater than the reference value, that is, the bus has experienced a sudden increase. If ΔU<0, it means that the current instantaneous value of the bus voltage is less than the reference value, that is, the bus has experienced a sudden drop.

[0031] After determining whether the bus voltage mutation is a sudden increase or a sudden drop, determine the degree of the sudden increase or sudden drop, and respond in different ways according to the different degrees of the sudden increase or sudden drop. Specifically, when the voltage mutation value is greater than the voltage mutation value threshold, set the mutation range threshold. Divide the voltage mutation value by the reference value to obtain the mutation range value, compare the mutation range value with the mutation range threshold, and obtain different responses according to the comparison result. If the mutation range value is less than the mutation range threshold, it indicates that the range of the bus voltage mutation is small. If the mutation range value falls within the mutation range threshold, it indicates that the range of the bus voltage mutation is medium. If the mutation range value is greater than the mutation range threshold, it indicates that the range of the bus voltage mutation is large. Since it is divided into two cases of bus voltage sudden increase and sudden drop, the three cases of small mutation range, medium mutation range and large mutation range should be divided into bus voltage sudden increase mutation range small, bus voltage sudden increase mutation range medium, bus voltage sudden increase mutation range large, bus voltage sudden drop mutation range small, bus voltage sudden drop mutation range medium, bus voltage sudden drop mutation range large for processing. Among them: 1. For the case where the bus voltage surge is small, this problem is relatively minor and may be caused by a small load fluctuation or overshoot of the reactive compensation device. In this case, continuously detect the bus voltage to observe whether it recovers automatically. If it occurs frequently, check the reactive compensation device parameters. 2. For the case where the bus voltage surge is medium, this problem may be caused by the sudden removal of a large load or too fast adjustment of the device. In this case, check whether a large number of devices on the load side are disconnected from the system; adjust the action mechanism of the reactive compensation device to avoid overcompensation; if accompanied by power flow fluctuations, check whether there is equipment removal on the transmission line. 3. For the case where the bus voltage surge is large, this problem is usually caused by excess reactive power, line removal or abnormal generator excitation system. In this case, put in capacitors or adjust transformer taps to reduce the bus voltage; check the operating status of the generator excitation system to prevent overexcitation; if it is caused by line removal, it is necessary to quickly restore the system power flow balance. 4. For the case where the bus voltage sag is small, this problem may be caused by a small load fluctuation or a slight change in line impedance. In this case, continuously monitor the bus voltage to see if it recovers automatically; detect the load startup and consumption characteristics. 5. For situations where the bus voltage sags with a medium range, this problem may be caused by the startup of a large load, insufficient local reactive power, or changes in line impedance. In this case, invest in reactive power compensation equipment to make up for the reactive power shortage; check whether the load equipment starts abnormally and optimize the startup sequence; check whether the transmission line has overload or voltage drop points. 6. For situations where the bus voltage sags with a large range, this problem is usually caused by a short circuit fault, large-scale load startup, or insufficient power on the power supply side.In this case, start the fast protection device, isolate the fault line, and prevent the short-circuit current from continuing to impact; start the backup power supply or quickly adjust the engine output to restore the system power balance; check the operating status of the regional power grid and coordinate the reactive and active power dispatch. In general, when the bus voltage mutation value exceeds the voltage mutation value threshold, the degree of sudden increase or decrease can be evaluated by calculating the mutation range value, and graded response measures can be taken according to the size of the range. For the sudden increase problem, when the range is small, it is usually caused by small fluctuations or overshoot of reactive equipment, and only continuous monitoring and checking of reactive compensation parameters are required; medium range may be caused by sudden load removal or too fast adjustment, and the compensation mechanism needs to be adjusted and the load separation situation needs to be checked; large range is usually caused by excess reactive power, line removal or abnormal generator excitation, and the equipment operation status needs to be adjusted quickly to restore the balance of the power grid. For the sudden drop problem, when the range is small, it may be caused by load fluctuation or slight change in line impedance, and only the load characteristics need to be monitored and analyzed; when the range is medium, it may be caused by large load startup or insufficient reactive power, and compensation equipment needs to be invested and the equipment startup sequence needs to be optimized; when the range is large, it is usually related to short circuit faults, large-scale load startup or insufficient power, and it is necessary to quickly isolate the fault, dispatch power and restore balance. For example: Assume that the instantaneous value of bus voltage U1 = 10.5kV, and the bus voltage reference value U2 = 10kV. The voltage mutation value ΔU = |U1-U2| = |10.5-10| = 0.5kV. The set voltage mutation threshold is 0.3kV, because 0.5kV> 0.3kV, further analysis is required. The mutation range value is 0.5÷10 = 0.05. The mutation range threshold is set to 0.02-0.04, and 0.05 is greater than the mutation range threshold, indicating that the bus voltage has a large sudden increase mutation range.

[0032] In general, the above distribution network fault judgment method based on bus voltage mutation obtains the instantaneous value of bus voltage in real time and compares it with the reference value to calculate the voltage mutation value to identify abnormal voltage changes. This method eliminates slow fluctuation interference through filtering algorithm, sets the voltage mutation value threshold, divides the mutation into two types: sudden increase and sudden drop, and adopts a graded response strategy according to the size of the mutation range (small, medium, large). When the voltage mutation range is small, usually no intervention is required, only continuous monitoring is required; when the range is medium or large, specific measures are taken for different types (such as reactive power excess, load fluctuation, short circuit fault, etc.), such as adjusting reactive compensation equipment, starting protection devices, and restoring system power balance. Through automated judgment technology, this method can quickly identify faults and isolate problems to ensure safe and stable operation of the power grid, while providing a basis for system optimization and equipment maintenance. It is widely applicable to distribution network operation monitoring, fault response and power grid optimization scenarios.

[0033] In addition, when the voltage mutation value is less than or equal to the voltage mutation value threshold, although the degree of bus voltage mutation is small, different processing operations need to be performed for different degrees of less than. Because the closer the voltage mutation value is to the voltage mutation value threshold, the higher the possibility that the bus voltage mutation exceeds the voltage mutation value threshold. In this case, compared with the case where the voltage mutation value is far away from the voltage mutation value threshold, there is no doubt that more attention should be paid to the case where the voltage mutation value is close to the voltage mutation value threshold. Specifically, a proximity threshold less than the voltage mutation value threshold is set. When the voltage mutation value is less than or equal to the voltage mutation value threshold, the voltage mutation value is compared with the proximity threshold, and different responses are obtained according to the comparison results. If the voltage mutation value is less than the proximity threshold, it indicates that the voltage mutation value is far away from the voltage mutation value threshold. In this case, it is sufficient to continue monitoring according to the original normal specifications. If the voltage mutation value is greater than or equal to the proximity threshold, it indicates that the voltage mutation value is close to the voltage mutation value threshold. In this case, since it is more likely to exceed the voltage mutation value threshold, it may cause greater voltage fluctuations or faults, so the monitoring frequency of the bus voltage is increased and attention to the operating status of related equipment is strengthened. In general, when the bus voltage mutation value is less than or equal to the voltage mutation value threshold, different treatment measures are taken according to the degree of the voltage mutation value from the voltage mutation value threshold. To this end, a reference value close to the voltage mutation value threshold, that is, the proximity threshold, can be set to compare the voltage mutation value with it. When the voltage mutation value is less than the proximity threshold, it indicates that the voltage fluctuation is small and far away from the voltage mutation value threshold. At this time, continuous monitoring can be carried out according to normal specifications without additional intervention; when the voltage mutation value is greater than or equal to the proximity threshold, it indicates that the mutation is close to the voltage mutation value threshold, and it may be easier to exceed the voltage mutation value threshold in the future, resulting in greater fluctuations or failures. Therefore, at this time, it is necessary to increase the monitoring frequency, track the bus voltage change trend in real time, and strengthen the attention to the operating status of related equipment. If necessary, adjust the compensation equipment or load distribution in advance to prevent the situation from escalating. This hierarchical management method can effectively optimize resource allocation and balance monitoring efficiency and grid stability.

[0034] There are two ways to increase the bus voltage monitoring frequency:

[0035] Method 1: shorten the original monitoring time interval, that is, shorten the monitoring cycle. Specifically: divide the distance between the near threshold and the voltage mutation threshold into N areas, from small to large, namely the first area (the starting point is near the threshold), the second area...the Nth area (the end point is the voltage mutation threshold). Shorten the monitoring cycle proportionally starting from the first area. When the voltage mutation value is close to the voltage mutation threshold, obtain the voltage mutation value at this time, determine which area this voltage mutation value falls into, and the monitoring system is adjusted according to the shortened monitoring cycle corresponding to this area. Ensure that the closer to the voltage mutation value threshold, the higher the monitoring frequency.

[0036] Method 2: The monitoring cycle remains unchanged, and the number of monitoring times is increased within one monitoring cycle. Specifically: the distance between the near threshold and the voltage mutation threshold is evenly divided into N regions, which are the first region (the starting point is near the threshold), the second region...the Nth region (the end point is the voltage mutation threshold) from small to large. The number of monitoring times is increased proportionally starting from the first region. When the voltage mutation value is close to the voltage mutation threshold, the voltage mutation value at this time is obtained, and it is determined which region this voltage mutation value falls into. The monitoring system is adjusted according to the increased number of monitoring times corresponding to this region, so as to obtain more intensive data within a fixed monitoring cycle.

[0037] Both methods can flexibly respond to situations where voltage mutation values ​​are close to the threshold. By dynamically adjusting the monitoring frequency or density, they can timely capture voltage change trends and improve monitoring accuracy and response speed.

[0038] The above increase in monitoring frequency has both advantages and disadvantages. The advantage is that more attention can be paid to the power grid when approaching the voltage mutation value threshold, so that the voltage mutation value of the bus voltage can be discovered in time when it exceeds the voltage mutation value threshold. The disadvantage is that it will increase the pressure on the monitoring system. If the bus voltage is only close to the voltage mutation value threshold but not exceeded for a long time, it will continue to cause monitoring burden to the monitoring system. Therefore, under the above premise, the cycle number limit value M for increasing the monitoring frequency is set. If the voltage mutation value of the bus voltage is only close to the voltage mutation value monitoring threshold but not exceeded for M consecutive monitoring cycles, the monitoring system will restore the original standard monitoring times. That is, when the voltage mutation value of the bus voltage is less than or equal to the voltage mutation value threshold but greater than or equal to the threshold, the monitoring mode of the monitoring system is dynamically adjusted to mode one or mode two. Thereafter, if the voltage mutation value threshold does not exceed the voltage mutation value threshold within M consecutive monitoring cycles, the system determines that the current voltage mutation value change trend is stable, and the monitoring system restores the original monitoring mode. The advantages of this dynamic adjustment mechanism are: timeliness: when the voltage mutation value is close to the voltage mutation value threshold, the monitoring frequency can be quickly increased to ensure that any abnormal fluctuations can be discovered in time. Flexibility: By setting the number limit value M, the pressure on the system caused by long-term high-frequency monitoring is avoided, and the normal monitoring level is restored in time after the fluctuation is stabilized. Resource optimization: While ensuring the safety of the power grid, the burden of the monitoring system and the efficiency of resource allocation are reasonably balanced.

[0039] In the embodiments disclosed in the present invention, the processes described above with reference to the flowchart can be implemented as a computer software program. The embodiments disclosed in the present invention include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part, and / or installed from a removable medium. When the computer program is executed by the central processing unit, the above functions defined in the method of the present application are executed. It should be noted that the computer-readable medium mentioned above in the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media can include, but are not limited to: an electrical connection with one or more wire segments, a portable computer disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical fiber, a portable compact disk read-only memory, an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless segments, wire segments, optical cables, RF, etc., or any suitable combination of the above.

[0040] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the boxes can also occur in a different order than the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0041] Those skilled in the art should understand that the above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. A distribution network fault judgment method based on bus voltage mutation, characterized in that: The following steps are involved: The first step is to obtain the instantaneous value of the bus voltage mutation, subtract the bus voltage reference value from the instantaneous value and perform absolute value processing to obtain the voltage mutation value, which is used as a reference for subsequent judgment; The second step is to set the voltage mutation threshold by comprehensively considering the distribution network operation characteristics, operation standards and the bearing capacity of key power-consuming equipment. The bus voltage mutation fluctuation that does not exceed the voltage mutation threshold will not affect the continuous use of the distribution network. The third step is to compare the voltage mutation value with the voltage mutation value threshold. If the voltage mutation value is less than or equal to the voltage mutation value threshold, it indicates that the bus voltage fluctuation is within an acceptable range, and the system does not intervene and continues to monitor normally. If the voltage mutation value is greater than the voltage mutation value threshold, the fault type of the voltage mutation is determined, and different processing is performed according to the fault type.

2. The distribution network fault judgment method based on bus voltage mutation according to claim 1 is characterized in that: The bus voltage mutation fault types include sudden drop and sudden increase. If the difference between the instantaneous value of the bus voltage and the reference value is a positive number, it indicates that the instantaneous value of the bus voltage is greater than the reference value, and the mutation type is a sudden increase; if the difference between the instantaneous value of the bus voltage and the reference value is a negative value, it indicates that the instantaneous value of the bus voltage is less than the reference value, and the mutation type is a sudden drop.

3. The distribution network fault judgment method based on bus voltage mutation according to claim 2 is characterized in that: When the voltage mutation value is greater than the voltage mutation value threshold, the mutation range threshold is set, the voltage mutation value is divided by the reference value to obtain the mutation range value, the mutation range value is compared with the mutation range threshold, and different responses are obtained according to the comparison results.

4. The distribution network fault judgment method based on bus voltage mutation according to claim 3 is characterized in that: If the mutation range value is less than the mutation range threshold, it indicates that the range of the bus voltage mutation is small; if the mutation range value falls within the mutation range threshold, it indicates that the range of the bus voltage mutation is medium; if the mutation range value is greater than the mutation range threshold, it indicates that the range of the bus voltage mutation is large; among them, for a small sudden increase in bus voltage, continuously check the bus voltage or reactive compensation equipment parameters; for a medium sudden increase in bus voltage, adjust the reactive compensation equipment action mechanism; for a large sudden increase in bus voltage, use taps to reduce the bus voltage; for a small sudden drop in bus voltage, continue monitoring; for a medium sudden drop in bus voltage, add reactive compensation equipment; for a large sudden drop in bus voltage, check short circuits and isolate faulty lines.

5. The distribution network fault judgment method based on bus voltage mutation according to claim 1 is characterized in that: When the voltage mutation value is less than or equal to the voltage mutation value threshold, a proximity threshold is set, which is less than the voltage mutation value threshold, and the voltage mutation value is compared with the proximity threshold, and different responses are obtained according to the comparison result.

6. The distribution network fault judgment method based on bus voltage mutation according to claim 5 is characterized in that: If the voltage mutation value is less than the threshold, the monitoring system will continue to monitor normally; if the voltage mutation value is greater than or equal to the threshold, the bus voltage monitoring frequency will be increased.

7. The distribution network fault judgment method based on bus voltage mutation according to claim 6 is characterized in that: There are two ways to increase the bus voltage monitoring frequency. One is to shorten the original monitoring time interval, which is proportionally shortened according to the degree to which the voltage mutation value is close to the voltage mutation value threshold; the other is to keep the monitoring period unchanged and increase the number of monitoring times within one monitoring period, which is proportionally increased according to the degree to which the voltage mutation value is close to the voltage mutation value threshold.

8. The distribution network fault judgment method based on bus voltage mutation according to claim 7 is characterized in that: Set a cycle number limit value to increase the monitoring frequency. When the voltage mutation value of the bus voltage is less than or equal to the voltage mutation value threshold but greater than or equal to the threshold, the monitoring mode of the monitoring system is dynamically adjusted to mode 1 or mode 2. Thereafter, if the voltage mutation value threshold does not exceed the voltage mutation value threshold after consecutive monitoring cycles of the cycle number limit value, the system determines that the current voltage mutation value change trend is stable, and the monitoring system restores the original monitoring mode.

9. The distribution network fault judgment system based on bus voltage mutation according to any one of claims 1 to 8, characterized in that: include: Reference acquisition module: It is used to obtain the instantaneous value of the bus voltage mutation. The instantaneous value is subtracted from the reference value of the bus voltage and then processed into an absolute value to obtain the voltage mutation value. Threshold setting module: It is used to set the voltage mutation threshold value based on the comprehensive distribution network operation characteristics, operation standards and the bearing capacity of key power equipment; Comparison response module: It is used to compare the voltage mutation value with the voltage mutation value threshold. If the voltage mutation value is less than or equal to the voltage mutation value threshold, it indicates that the bus voltage fluctuation is within an acceptable range, and the system does not intervene and continues to monitor normally. If the voltage mutation value is greater than the voltage mutation value threshold, the fault type of the voltage mutation is determined, and different processing is performed according to the fault type.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement a distribution network fault judgment method based on bus voltage mutation as described in any one of claims 1 to 8.

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