A method and system for wide-area protection of integrated energy electrical systems

Abstract

The application discloses a kind of equipment integrated energy electrical system wide-area protection method and system, it is related to equipment integrated energy electrical system fault defense technical field, comprising the following steps: if the positive current mutation variable and negative current mutation variable of each protection area are greater than set mutation variable, then by differential protection criterion, first protection area and current second protection area are successively carried out continuity discrimination, if, preliminary identification current second protection area occurs internal fault;For each second protection area that is preliminarily identified as internal fault occurs, the similarity of corresponding actual output vector and each row vector of action matrix is calculated in turn, if the area corresponding to the row vector of maximum similarity is the second protection area, then determine that the second protection area occurs internal fault, then execute protection action to the second protection area, and the internal fault is cut off.This application can realize the fast and reliable identification of each area grounding fault of equipment integrated energy electrical system and wide-area protection.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of equipment comprehensive energy electrical system fault defense technology, in particular to an equipment comprehensive energy electrical system wide-area protection method and system. BACKGROUND

[0002] As a core component of modern electric equipment platform, the equipment comprehensive energy electrical system has the advantages of flexible structure, efficient energy distribution and compatibility with multiple loads, and can meet various complex application scenarios, which is of great significance to improve the overall energy management capability and system integration of the platform. The system usually integrates energy storage units, permanent magnet synchronous motor drive systems, electric air conditioner compressors, PTC heaters and other power loads, and has strong scalability and integration. When integrating some high-power pulse loads, the system needs to cope with the electrical impact caused by instantaneous high-power output. Such loads usually run with large current, especially in the high-intensity, fast-paced and multi-working-condition operating environment commonly seen in vehicle platforms, a wide-area protection system with fast response and strong anti-interference needs to be equipped to ensure the safety and stability of the vehicle platform.

[0003] Currently, the research on comprehensive energy systems is still mainly focused on the modeling and performance analysis of single devices, and there is a lack of system-level high-fidelity modeling methods covering power sources and multiple types of loads, especially in fault feature extraction and dynamic response analysis. With the continuous improvement of the electrification level of equipment platforms, various power sources and loads are deeply coupled on the same bus, and the system energy flow shows high dynamicity and complex interaction behavior, making it difficult for traditional overcurrent protection-based strategies to meet the requirements.

[0004] In the protection process of the equipment comprehensive energy system, the traditional scheme relies on overcurrent protection and other fixed value methods. When dealing with high dynamic and short-time high-current special loads, such as pulse loads, it is difficult to effectively distinguish between transient current changes and actual fault signals during system operation, which can easily cause misjudgment and result in false protection actions of the system. At the same time, the traditional scheme has the problems of low fault area recognition accuracy and response lag in conditions with frequent topology changes and dynamic load switching, which cannot meet the comprehensive requirements of protection action speed and accuracy under actual combat conditions of the comprehensive energy system. SUMMARY

[0005] Based on the defects of the existing technology, the present application provides an equipment comprehensive energy electrical system wide-area protection method and system, which solves the existing problems.

[0006] The present application adopts the following technical solutions:

[0007] In a first aspect, the present application provides a method for wide-area protection of an integrated energy electrical system, wherein an area where a storage unit is located in the integrated energy electrical system is divided into a first protection area, and areas where each power load is located are divided into a plurality of second protection areas, and the method comprises the following steps:

[0008] calculating corresponding positive current mutation and negative current mutation based on the real-time collected positive current and negative current of the first protection area and the plurality of second protection areas;

[0009] if the positive current mutation and the negative current mutation of the first protection area and the current second protection area are both greater than a set mutation, then the continuity of the first protection area and the current second protection area is successively discriminated by a differential protection criterion, if the discrimination is successful, then it is preliminarily identified that an internal fault occurs in the current second protection area, and meanwhile, actual protection action signals output by each second protection area are collected to form an actual output vector;

[0010] for each second protection area preliminarily identified as having an internal fault, the similarity between the actual output vector corresponding to the second protection area and each row vector of an action matrix is successively calculated, if the area corresponding to the row vector with the greatest similarity is the second protection area, then it is determined that an internal fault occurs in the second protection area, and then a protection action is performed on the second protection area based on the corresponding actual protection action signal to clear the internal fault; wherein, when each load in the integrated energy electrical system fails, the theoretical protection action signals output by each second protection area form corresponding row vectors, and the action matrix is constructed by a plurality of row vectors.

[0011] Preferably, the set mutation is greater than a current fluctuation setting value when the integrated energy electrical system is normally operated.

[0012] Preferably, the continuity of the first protection area and the current second protection area is successively discriminated by the differential protection criterion, and specifically comprises the following steps:

[0013] if the positive current mutation and the negative current mutation of the first protection area satisfy the differential protection criterion for 5 times out of 10 times within a set time, then the continuity of the current second protection area is discriminated;

[0014] if the positive current mutation and the negative current mutation of the current second protection area satisfy the differential protection criterion for 8 times out of 10 times within a set time, then it is preliminarily identified that an internal fault occurs in the current second protection area;

[0015] the differential protection criterion is specifically as follows:

[0016] ;

[0017] wherein, is t the positive and negative current abrupt change of the energy storage unit or each power load at the moment, I set1 is the first action current setting value.

[0018] Preferably, if an internal fault occurs in the current second protection area, each second protection area outputs a corresponding actual protection action signal, and the protection action signal is as follows:

[0019] ;

[0020] wherein, D i is the protection action signal of the i th second protection area.

[0021] Preferably, the similarity between the actual output vector corresponding to the second protection area and each row vector of the action matrix is calculated in sequence by using a cosine similarity formula, and the cosine similarity formula is specifically as follows:

[0022] ;

[0023] wherein, is the similarity, x 2 、x 3 、…、x n is the actual protection action signal output by each second protection area when any second protection area fails, y 2 、y 3 、…、y n is each row vector of the action matrix.

[0024] Preferably, if the region corresponding to the row vector with the maximum similarity is not the second protection area, it is determined that the second protection area has no internal fault.

[0025] Preferably, the method further comprises:

[0026] After the internal fault is removed, it is determined whether the fault is removed or not, and if not, it is determined that the breaker at the fault position is malfunctioning;

[0027] If it is determined that the breaker at the fault position is malfunctioning, the positive and negative current abrupt change of each second protection area is added, and when three consecutive points satisfy the action criterion, the battery outlet breaker is tripped to cut off the system power supply;

[0028] The action criterion is specifically as follows:

[0029] ;

[0030] In the formula, is the sum of the positive and negative current abrupt variables of all second protection areas, 、 are the positive and negative current abrupt variables of each second protection area, is the second action current setting value.

[0031] In a second aspect, the application provides a wide-area protection system for a comprehensive energy electrical system, which divides an area where an energy storage unit is located in the comprehensive energy electrical system into a first protection area, and divides an area where each power load is located into a plurality of second protection areas, and the wide-area protection system comprises:

[0032] a calculation module, configured to calculate corresponding positive and negative current abrupt variables based on positive and negative currents collected in real time by the first protection area and the plurality of second protection areas;

[0033] a discrimination module, configured to, if the positive and negative current abrupt variables of the first protection area and a current second protection area are both greater than a set abrupt variable, successively perform continuity discrimination on the first protection area and the current second protection area through a differential protection criterion, and if the discrimination is successful, preliminarily identify that an internal fault occurs in the current second protection area, and simultaneously collect actual protection action signals output by each second protection area to form an actual output vector;

[0034] a protection module, configured to, for each second protection area preliminarily identified as having an internal fault, successively calculate similarity between the actual output vector corresponding to the second protection area and each row vector of an action matrix, and if the second protection area corresponding to the row vector with the greatest similarity has an internal fault, determine that the second protection area has an internal fault, and perform a protection action on the second protection area based on the corresponding actual protection action signal to clear the internal fault; wherein, when each load in the comprehensive energy electrical system has a fault, theoretical protection action signals output by each second protection area form corresponding row vectors, and the action matrix is constructed through the plurality of row vectors.

[0035] Compared with the prior art, the above at least one technical solution of the application can achieve the following beneficial effects:

[0036] The application firstly divides the area where the energy storage unit of the comprehensive energy electrical system is located into a first protection area, divides the area where each power load is located into a plurality of second protection areas respectively, and collects current signals in real time. The positive electrode current and the negative electrode current collected in real time calculate corresponding positive electrode current mutation and negative electrode current mutation, and construct protection starting conditions. When the protection starts, the continuity of the first protection area and the current second protection area is discriminated in turn through the differential protection criterion, the rapid preliminary identification of the fault range is realized, and the reliability and speed of the subsequent action are ensured. For each second protection area preliminarily identified as an area fault, the cosine similarity analysis is introduced, the similarity of the actual output vector and the preset action matrix is compared, if the region corresponding to the row vector with the maximum similarity is the second protection area, it is determined that the second protection area has an area fault. The application determines that a second protection area has an area fault through twice judgment, and improves the accuracy of subsequent protection. Finally, the protection action is performed on the second protection area based on the corresponding actual protection action signal, and the area fault is removed. The application can quickly and clearly identify the protection area where the area fault occurs, improve the identification accuracy of the fault area, avoid misoperation caused by transient current change, and still correctly act when some protection signals are missing, thereby enhancing the robustness. The comprehensive requirements of protection action speed and accuracy under the actual combat conditions of the comprehensive energy system are met. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0038] Figure 1 The differential protection configuration schematic diagram of the comprehensive energy power system of the embodiment 1 of the present application is shown in the figure.

[0039] Figure 2 The wide-area protection flow chart based on sampling value differential of the embodiment 1 of the present application is shown in the figure.

[0040] Figure 3 The curve graph of the differential current value of each protection changing with time of the embodiment 2 of the present application is shown in the figure.

[0041] Figure 4 The actual protection action signal of the embodiment 2 of the present application is shown in the figure.

[0042] Figure 5 The similarity of the actual output vector and the action matrix F of the embodiment 2 of the present application is shown in the figure.

[0043] Figure 6A schematic diagram of the battery outlet positive electrode current change curve over time for the embodiment 3 of the present application;

[0044] Figure 7 A schematic diagram of the each protection differential current value change curve over time for the embodiment 3 of the present application;

[0045] Figure 8 The actual protection action signal for the embodiment 4 of the present application;

[0046] Figure 9 The similarity of the actual output vector and the action matrix F for the embodiment 4 of the present application;

[0047] Figure 10 The sum of all currents in the differential ring for the embodiment 5 of the present application. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0049] Embodiment 1

[0050] In view of the above problems, the present application provides a wide-area protection method for an integrated energy electrical system, specifically a wide-area protection method based on sampled value current differential, which can realize fast and reliable identification of the ground fault in the area where each element of the integrated energy electrical system is located, and has a backup protection function. Referring to Figure 2 , the method specifically includes the following steps:

[0051] Step 1: dividing the area where the energy storage unit in the integrated energy electrical system is located into a first protection area, and dividing the area where each power load is located into a plurality of second protection areas, referring to Figure 1The first protection zone is Protection 1. Multiple second protection zones include Protection 2, Protection 3, Protection 4, Protection 5, and Protection 6. Among them, the components in Protection 1 are the battery and BMS (Battery Management System), the components in Protection 2 are the air conditioning compressor, the components in Protection 3 are the PTC (Positive Temperature Coefficient Heater), the components in Protection 4 are the DC / DC (Direct Current / Direct Current Converter), the components in Protection 5 are special loads, and the components in Protection 6 are the PMSM (Permanent Magnet Synchronous Motor).

[0052] A 20kHz high-speed current transformer is installed in the energy storage unit of the integrated energy electrical system and at each power load connection point to monitor the incoming and outgoing currents in this area. i P and i N Real-time sampling is performed, and all protected areas achieve high-speed data communication via optical fiber. If the optical fiber network communication is abnormal, the protection is blocked. The action signals of each protection are output through optical fiber communication, and the battery output action signal is used to achieve pre-judgment, reducing the possibility of false tripping.

[0053] A 20kHz high-speed current transformer is installed at the power outlet and each load connection point to capture the transient current signal, calculate the current change, and construct the protection start criterion based on this. To avoid the influence of bad data points, the protection start condition is set to the condition that three data points are continuously monitored and meet the criterion, which effectively avoids false operation.

[0054] Step 2: Calculate the sudden change in current of the incoming and outgoing lines in each protected area. The calculation method is shown in the following formula:

[0055] (1)

[0056] In the formula, The current mutation amount m One calculated value; The first current m One sampling point; M Take interval The number of sampled data, M =40, the sampling frequency is 20kHz, so 2ms corresponds to 40 sampling points. Both the positive and negative currents in the protected area are calculated.

[0057] Step 3: Use the current surge detection method as the protection start criterion. Determine whether the protection is started using the following formula:

[0058] (2)

[0059] wherein, is the current mutation value, is the starting threshold value, i.e. the setting mutation value, which is set according to the current fluctuation greater than the current fluctuation during normal operation of the system. In order to avoid the influence of bad data points, the starting condition of the protection is set to be that 3 sampling points are continuously monitored to satisfy the criterion. Both the current mutation value of the positive electrode current and the current mutation value of the negative electrode current (i.e. the current mutation value of the incoming and outgoing line currents) need to be greater than the starting threshold value.

[0060] Step 4: After the fault occurs, the fault component sampling value differential protection criterion is immediately put into operation. The sampling value differential protection is to differentiate the sampling value at each time point. The first protection area and the current second protection area are successively differentiated through the differential protection criterion. If the differentiation is successful, it is preliminarily identified that the fault occurs in the current second protection area.

[0061] Specifically, if at least S times satisfy the criterion in the continuous R times of differentiation, it is preliminarily identified that the fault occurs in the area. The criterion is as follows:

[0062] (3)

[0063] wherein, are respectively t the positive electrode current mutation value and the negative electrode current mutation value of the energy storage unit or each power load at the time point; I set1 is the first action current setting value, which is set according to the maximum current mutation value greater than the fault outside the area. The influence of the fault in other areas on the current area is avoided.

[0064] In order to ensure the reliability and rapidity of the action, the judgment is realized in the 0.5 ms data window. The protection I takes R1=10, S1=5, and the remaining protection areas take R2=10, S2=8. i i =2,3… n ).

[0065] After the protection is started, the fault component sampling value differential criterion is immediately put into operation. The criterion differentiates the sampling value at each time point, and continuously satisfies the criterion at multiple points. The rapid confirmation of the fault in the area is realized in the continuous R times of differentiation, and the response time is controlled within 0.5 milliseconds. The criterion fully considers the mutual inductor distortion and noise interference and other factors during the fault process. The R-S value is constructed to ensure the reliability and rapidity of the action.

[0066] ​Step 5: Constructing the wide-area protection strategy according to the protection action signals of each protection zone. For the protection action signals of each element except for protection one, the output thereof can be defined according to the fault identification condition D i As follows:

[0067] (4)

[0068] In the formula, D i is the protection action signal of the first second protection zone, i .

[0069] When a fault occurs in each element of the system, the theoretical protection action signals of each protection zone can form an action matrix F, as shown in Table 1. In the table, P2, P3, …, etc. respectively represent the protection action signals of each protection zone in Figure 1 Di F2, F3, etc. respectively represent that each protection zone is in a fault state and becomes a fault zone.

[0070] Table 1 Action matrix F

[0071]

[0072] The action matrix F is constructed, and the cosine similarity between the protection output signal and the preset action matrix is analyzed. The similarity between the actual output signal of the other protection unit and the preset action matrix is compared, the vector with the maximum similarity is calculated, and the final protection action is determined. The fault positioning accuracy is improved, and the robustness is enhanced while the protection signal is missing.

[0073] Step 6: For each second protection zone preliminarily identified as having an intra-zone fault, the similarity between the actual output vector corresponding to the second protection zone and each row vector of the action matrix is calculated in turn:

[0074] (5)

[0075] In the formula, x 2 、x 3 、…、x n is the actual protection action signal output by each second protection zone when any second protection zone is in a fault state, y 2 、y 3 、…、y n is each row vector of the action matrix.

[0076] ​​If the region corresponding to the most similar row vector is the second protection region, it is determined that the second protection region has an internal fault, a trip command is issued, a protection action is performed on the current second protection region, and the fault is cut off. Otherwise, it is determined that an external fault occurs.

[0077] The criterion utilizes the signal of battery outlet protection, reduces the probability of protection misoperation, correctly operates when some protection signals are missing, improves the accuracy of protection, and only needs to transmit a logic signal, so the reliability is high.

[0078] Step 7: If the fault cannot be correctly cut off after 5 ms of the action signal, it is indicated that the breaker at the fault fails, and the wide-area backup protection is put into operation. The differential ring is constructed as shown by a dashed line. The action criterion is as follows: the currents of each current transformer are added. When the following formula is met for 3 consecutive sampling points, the battery outlet breaker is tripped to cut off the system power supply, and the wide-area backup protection is realized. Figure 1 The differential ring is constructed as shown by a dashed line. The action criterion is as follows: the currents of each current transformer are added. When the following formula is met for 3 consecutive sampling points, the battery outlet breaker is tripped to cut off the system power supply, and the wide-area backup protection is realized.

[0079] (6)

[0080] In the formula, is the sum of the positive and negative current sudden changes in the differential ring; , are the positive and negative current sudden changes of each differential protection, respectively, and j=2, 3,..., n; is the second action current setting value, which is set to avoid the load current fluctuation in normal operation.

[0081] A cooperative fault-tolerant mechanism is designed, and in the case of failure of the main protection, the wide-area backup protection mechanism is activated. The mechanism constructs a differential ring, superimposes the sudden changes of all detection points, constructs a wide-area backup protection criterion, and ensures that the fault isolation can still be reliably realized when the breaker fails.

[0082] Embodiment 2

[0083] To verify the correctness of the proposed protection, a comprehensive energy electrical system model as shown in Figure 1 is built in MATLAB / Simulink. The model integration includes energy storage batteries, DC / DC external charging systems, PMSM inverter-motor systems, air conditioner compressors, PTC heaters, and special weapon loads, and the connection line impedance is ignored. The system parameters are shown in Table 2.

[0084] Table 2 Simulation model parameters

[0085]

[0086] The protection six-range fault simulation.

[0087] The method is verified by taking the single-phase short-circuit grounding of the PMSM AC side as an example. The A-phase grounding fault occurs at the PMSM AC side for 0.2 s, and the transition resistance is 10 Ω.

[0088] The differential current values of the respective protections are as shown in Figure 3 It can be seen that a larger differential current occurs at the protection one and the protection six, When the differential current is 0.25 A, the protection six can identify the fault after 1.4 ms by using the method, and the protections two to five are not started. Referring to Figure 4 , the actual output vector of the protections two to six is (-1, -1, -1, -1, 1), and the similarity between the actual output vector and the action matrix F is (0.2, 0.2, 0.2, 0.2, 1) calculated according to formula (5), as shown in Figure 5 It can be judged that the fault is in the protection six range, which is the same as the actual range.

[0089] Example 3

[0090] The pulse load is put into simulation.

[0091] The pulse load is put into operation for 0.2 s, and the battery outlet positive current and the differential current values of the respective protections change with time, as shown in Figure 6 and Figure 7 It can be seen that a larger impact current occurs in the system when the pulse load is put into operation, but the differential current values measured at the respective protections are all less than , and the protections are not started. It is proved that the method will not cause the protection to malfunction when the pulse load is put into operation.

[0092] Example 4

[0093] Fault tolerance analysis.

[0094] It is assumed that the A-phase grounding fault occurs at the PMSM AC side for 0.2 s, and the transition resistance is 10 Ω. The protection six is started but fails to output the action signal. At this time, referring to Figure 8 , the actual output vector of the protections two to six is (-1, -1, -1, -1, 0), and the similarity between the actual output vector and the action matrix is (0.447, 0.447, 0.447, 0.447, 0.894), that is, it can be judged that the fault occurs in the protection six range, as shown in Figure 9 , which is the same as the actual fault range.

[0095] Example 5

[0096] Backup protection analysis.

[0097] It is assumed that the A-phase grounding fault occurs at the PMSM AC side for 0.2 s, and the transition resistance is 10 Ω. The protection six correctly outputs the action signal but the circuit breaker at the protection six fails. The backup protection is started after 5 ms, and the sum of the positive and negative currents in the differential ring is as shown inFigure 10 The fault can be immediately identified, and an action signal is sent to cut off the power supply of the system.

[0098] Based on the same concept, the application also provides a wide-area protection system for an integrated energy electrical system, comprising a calculation module, a discrimination module and a protection module.

[0099] The calculation module is used to calculate the corresponding positive current mutation and negative current mutation based on the real-time collected positive current and negative current of the first protection area and the plurality of second protection areas.

[0100] The discrimination module is used to sequentially perform continuity discrimination on the first protection area and the current second protection area through the differential protection criterion if the positive current mutation and the negative current mutation of the first protection area and the current second protection area are both greater than the set mutation, and if the discrimination is successful, the current second protection area is preliminarily identified as having an internal fault, and the actual protection action signals output by each second protection area are collected to form an actual output vector.

[0101] The protection module is used to sequentially calculate the similarity between the actual output vector corresponding to each second protection area preliminarily identified as having an internal fault and each row vector of the action matrix, and if the region corresponding to the row vector with the maximum similarity is the second protection area, it is determined that the second protection area has an internal fault, and then the protection action is performed on the second protection area based on the corresponding actual protection action signal to cut off the internal fault; wherein when each load in the integrated energy electrical system fails, the theoretical protection action signals output by each second protection area form a corresponding row vector, and the action matrix is constructed through a plurality of row vectors.

[0102] The application has rapid, accurate and reliable grounding fault detection capability. The current signal is collected by a 20kHz high-speed current transformer, and data transmission between multiple nodes is realized through high-speed optical fiber communication technology. The current mutation is calculated, and the protection starting condition is constructed. After starting, the protection criterion based on the sampling value difference is constructed, and the rapid confirmation of the fault range is realized by combining the multi-point continuous satisfaction of the criterion, and the response time is controlled within 0.5 milliseconds. The action matrix is constructed, the cosine similarity analysis is introduced, the similarity between the protection output signal and the preset action matrix is compared, and the accuracy of the protection is improved. In the case of protection failure, the wide-area backup protection mechanism is activated, the judgment is made based on the sum of the mutations of all sampling points in the differential ring, and the fault isolation is still reliably realized when the circuit breaker fails. Through the multi-level and multi-parameter discrimination algorithm, the current interference, noise and other factors are fully considered, the anti-interference ability and reliability of the protection are effectively improved, and the application has the significant technical advantages of rapid response, low misjudgment rate and strong reliability.

[0103] While the preferred embodiments of the application have been described, additional variations and modifications can be made to these embodiments by those skilled in the art once they have the benefit of the present disclosure without departing from the spirit and scope of the application. Accordingly, it is intended that the appended claims include all such modifications and variations as fall within the scope of the present application.

[0104] It is apparent that those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. It is therefore intended that the present application cover all such changes and modifications that are within its scope.

Claims

1. A method for wide-area protection of an integrated energy electrical system, characterized in that, The area where the energy storage unit is located in the integrated energy electrical system is divided into a first protection zone, and the areas where each power load is located are divided into multiple second protection zones. The wide-area protection method includes the following steps: The corresponding positive current change and negative current change are calculated based on the positive current and negative current collected in real time in the first protection area and multiple second protection areas. If the positive current change and negative current change in the first protection zone and the current second protection zone are both greater than the set change, the first protection zone and the current second protection zone are sequentially judged by the differential protection criterion. If the judgment is successful, the fault in the current second protection zone is initially identified. At the same time, the actual protection action signals output by each second protection zone are collected to form the actual output vector. For each second protection zone initially identified as having an in-zone fault, the similarity between the actual output vector corresponding to the second protection zone and each row vector of the action matrix is ​​calculated sequentially. If the area corresponding to the row vector with the highest similarity is the second protection zone, then it is determined that the second protection zone has an in-zone fault. Then, based on the corresponding actual protection action signal, protection action is performed on the second protection zone to clear the in-zone fault. Among them, when each load in the equipment integrated energy electrical system fails, the theoretical protection action signal output by each second protection zone forms a corresponding row vector, and the action matrix is ​​constructed by multiple row vectors. The step of sequentially determining the continuity of the first protection zone and the current second protection zone using differential protection criteria specifically includes the following steps: The differential protection criteria are as follows: ； In the formula, for t The instantaneous changes in positive and negative current of the energy storage unit or each electrical load. I set1 This is the first operating current setting value; If, within a set time period, the positive current change and negative current change in the first protection zone satisfy the differential protection criterion 5 times out of 10 consecutive times, then the current second protection zone is continuously judged. If, within a set time period, the positive current change and negative current change in the current second protection zone meet the differential protection criterion 8 out of 10 consecutive times, then an intra-zone fault is initially identified in the current second protection zone.

2. The method for wide-area protection of an integrated energy electrical system as described in claim 1, characterized in that, The set mutation amount is greater than the current fluctuation setting during normal operation of the equipment's integrated energy electrical system.

3. The method for wide-area protection of an integrated energy electrical system as described in claim 1, characterized in that, If a fault occurs within the current second protection zone, each second protection zone will output a corresponding actual protection action signal, as shown below: ； In the formula, D i For the first i The protection action signal for the second protection zone.

4. The method for wide-area protection of an integrated energy electrical system as described in claim 1, characterized in that, The similarity between the actual output vector corresponding to the second protection area and each row vector of the action matrix is ​​calculated sequentially using the cosine similarity formula, which is shown below: ； In the formula, For similarity, x 2 、x 3 、…、x n This refers to the actual protection action signal output by each second protection zone when a fault occurs in any second protection zone. y 2 、y 3 、…、y n These are the row vectors of the action matrix.

5. A method for wide-area protection of an integrated energy electrical system as described in claim 1, characterized in that, If the region corresponding to the row vector with the highest similarity is not the second protection region, then the second protection region is determined to be free of faults.

6. The method for wide-area protection of an integrated energy electrical system as described in claim 1, characterized in that, Also includes: After the fault within the area is cleared, a judgment is made. If the fault is not cleared, the circuit breaker at the fault location is determined to be faulty. If the circuit breaker at the fault location is determined to be faulty, the current of the positive current change and the current of the negative current change in all the second protection zones are added together; when the action criteria are met at 3 consecutive points, the battery outlet circuit breaker is tripped to cut off the system power supply. The specific criteria for determining the action are as follows: ； In the formula, It is the sum of the positive and negative current surges in all the second protection zones. , These represent the sudden changes in current at the positive and negative electrodes of each second protection zone. This is the setting value for the second operating current.

7. A wide-area protection system for an integrated energy electrical system, characterized in that, The area where the energy storage unit is located in the integrated energy electrical system is divided into a first protection zone, and the areas where each power load is located are divided into multiple second protection zones. The wide-area protection system includes: The calculation module is used to calculate the corresponding positive current change and negative current change based on the positive current and negative current collected in real time from the first protection area and multiple second protection areas. The discrimination module is used to continuously discriminate between the first protection zone and the current second protection zone in sequence according to the differential protection criteria if the positive current change and negative current change of the first protection zone and the current second protection zone are both greater than the set change. If the discrimination is successful, it will initially identify that a fault has occurred in the current second protection zone, and at the same time collect the actual protection action signals output by each second protection zone to form the actual output vector. The protection module is used to calculate the similarity between the actual output vector corresponding to each second protection zone initially identified as having a fault within the zone and each row vector of the action matrix. If the area corresponding to the row vector with the highest similarity is the second protection zone, then it is determined that a fault has occurred in the second protection zone. Based on the corresponding actual protection action signal, a protection action is performed on the second protection zone to clear the fault within the zone. When a fault occurs in any load in the integrated energy electrical system, the theoretical protection action signal output by each second protection zone forms a corresponding row vector, and the action matrix is ​​constructed by multiple row vectors. The step of sequentially determining the continuity of the first protection zone and the current second protection zone using differential protection criteria specifically includes the following steps: The differential protection criteria are as follows: ； In the formula, for t The instantaneous changes in positive and negative current of the energy storage unit or each electrical load. I set1 This is the first operating current setting value; If, within a set time period, the positive current change and negative current change in the first protection zone satisfy the differential protection criterion 5 times out of 10 consecutive times, then the current second protection zone is continuously judged. If, within a set time period, the positive current change and negative current change in the current second protection zone meet the differential protection criterion 8 out of 10 consecutive times, then an intra-zone fault is initially identified in the current second protection zone.

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