Grid-connected side safety management and control system and method for high-voltage users of power grid

Abstract

The invention relates to a safety management and control system and method for a grid-connected side of a high-voltage user of a power grid. The system comprises: a portable insulation detection device selects an insulation detection mode or a fault tracing mode; in the insulation detection mode, the portable insulation detection device injects a preset harmonic current to a user transformer substation side; the harmonic voltage and the harmonic current are recovered through the fixed monitoring device, a first insulation resistance value is obtained through calculation, and whether the ground wire is not dismounted exists or not is judged; in a fault traceability mode, the portable insulation detection device obtains an actual wiring mode of a user transformer substation and voltage data and current data of each conductive branch through the fixed monitoring device; calculating a second insulation resistance value according to the actual wiring mode, the voltage data and the current data; and judging whether a power grid override trip condition caused by untimely removal of an internal fault exists in the user transformer substation or not. And safety control and technical control of the power grid on various operations or scenes of the user transformer substation are realized.

Description

Technical Field

[0001] The present invention relates to the field of power grid safety technology, and in particular to a power grid high-voltage user grid-connected side safety management and control system and method. Background Art

[0002] With the advancement of the "Dual Carbon" strategy, a large number of distributed photovoltaic power sources are being rapidly built and connected to the grid. Various industries are steadily reducing both energy consumption and carbon emissions through clean electricity substitution. The surge in grid-connected power sources and electricity demand has led to a growing number of substations and power plants being built, operated, and maintained by users themselves. This has also led to a sharp increase in grid-related power outages, maintenance, and troubleshooting. Traditionally, tasks such as power outage testing, ground wire removal, and on-site fault finding on the grid side of the grid rely primarily on high-voltage electricians at user substations (power plants) following telephone instructions from the grid dispatching agency, lacking auxiliary technical support tools. This has raised concerns about the effectiveness of on-site electricians and the standardization of fault finding coordination. The grid is unable to monitor the status of on-site equipment in real time, lacking safety management and control technology.

[0003] For example, during power transmission on a 500 kV line in one location, a human error prevented the grounding switch on the power plant side from being opened. This resulted in power being transmitted with the switch still on, causing serious consequences. Similar incidents are more likely to occur at power plants and substations operating in the 10 kV to 110 kV voltage range, due to limitations in user safety management and high-voltage electrical engineering experience. The National Energy Administration and the Central China Regulatory Bureau have successively issued a series of safety management requirements for user-substations, including measures for grid security risk management and detailed implementation rules for power grid-connected operations. This requires urgent breakthroughs in safety management and fault tracing technologies for the grid-connected side of user substations. Summary of the Invention

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] In a first aspect, a grid-connected high-voltage user safety management and control system is provided, comprising:

[0006] A portable insulation detection device and a fixed monitoring device; the portable insulation detection device is connected to the coupling point between the user's substation and the power grid, and the fixed monitoring device is installed at the user's substation to monitor the actual wiring method of the user's substation and the voltage and current data of each conductive branch; a communication connection is established between the portable insulation detection device and the fixed monitoring device;

[0007] Portable insulation testing device, used to select insulation testing mode or fault tracing mode;

[0008] When in insulation testing mode, the portable insulation testing device injects a preset harmonic current into the user's substation. The fixed monitoring device collects the harmonic voltage and harmonic current, calculates the first insulation resistance value based on the harmonic voltage and harmonic current, and determines whether the grounding wire is still in place based on the inherent safety check logic and the first insulation resistance value.

[0009] When in fault tracing mode, the portable insulation detection device obtains the actual wiring method of the user's substation through the fixed monitoring device; collects the voltage data and current data of each conductive branch in a specified period of time through the fixed monitoring device; calculates the second insulation resistance value of each conductive branch in the specified period of time based on the actual wiring method, voltage data and current data; and judges whether there is a grid over-tripping situation caused by the failure to eliminate the internal fault in time in the user's substation based on the grounding resistance type fault analysis algorithm and the second insulation resistance value.

[0010] Furthermore, the portable insulation detection device includes a harmonic drive control module, a harmonic generator, a signal analysis and logic processing module, a first communication module, a line connection part and a first human-computer interaction module;

[0011] The line hanging part is a hook-type sensor, which is fixed to the coupling point through clamp-type contact and self-locking structure;

[0012] The harmonic drive control module includes a battery unit, an isolation unit and a dual-frequency power output unit;

[0013] The signal analysis and logic processing module includes a charging unit, a signal analysis and logic processor and a first current and voltage detection unit;

[0014] The first human-computer interaction module includes a first key input unit and a first display unit.

[0015] Furthermore, the fixed monitoring device includes a monitoring logic configuration module, a signal acquisition and logic processing module, a second communication module and a second human-computer interaction module;

[0016] The monitoring logic configuration module includes a virtual monitoring point configuration unit and a wiring mode maintenance unit; the virtual monitoring point configuration unit is used to configure virtual monitoring points for monitoring current and voltage;

[0017] The signal acquisition and logic processing module includes a device status verification unit, a signal acquisition and logic processor, and a second current and voltage detection unit;

[0018] The second human-computer interaction module includes a second key input unit, a second display unit and a voice and alarm unit.

[0019] Furthermore, when the hook-type sensor is connected to the coupling point, the portable insulation detection device is powered on, and the first current and voltage detection unit obtains the test current and test voltage of the hook-type sensor at the coupling point;

[0020] The signal analysis and logic processor determines whether the harmonic output meets the requirements based on the test current and the test voltage. If it meets the requirements, it is determined that the self-test is qualified; if it does not meet the requirements, it is determined that the self-test is unqualified.

[0021] Furthermore, when it is determined that the self-test is qualified, the first communication module of the portable insulation detection device and the second communication module of the fixed monitoring device are switched to a preset wireless public network frequency and connected to the power dedicated network.

[0022] Furthermore, the first human-machine interaction module is used to select the insulation detection mode or the fault tracing mode according to the mode instruction input by the operator in the first key input unit.

[0023] Furthermore, when in insulation detection mode, the harmonic drive control module generates a harmonic generation control signal according to insulation detection requirements;

[0024] The harmonic generator generates a preset harmonic current of a target frequency according to a harmonic generation control signal, and injects the preset harmonic current into the user substation side at the coupling point through a hook-type sensor;

[0025] The fixed monitoring device collects harmonic voltage and harmonic current at the virtual monitoring point of each conductive branch through the signal acquisition and logic processing module; and sends the harmonic voltage and harmonic current to the first communication module of the portable insulation detection device through the second communication module;

[0026] The signal analysis and logic processor calculates a first insulation resistance value based on the harmonic voltage and the harmonic current, and compares the first insulation resistance value with an insulation resistance reference threshold based on an inherent safety check logic. If the first insulation resistance value is less than the insulation resistance reference threshold, it is determined that the grounding wire has not been removed; if the first insulation resistance value is not less than the insulation resistance reference threshold, it is determined that the grounding wire has not been removed.

[0027] Furthermore, the signal analysis and logic processor obtains the first frequency based on the injection dual-frequency method. Time harmonic voltage and harmonic currents and the second frequency Time harmonic voltage and harmonic currents , and is the voltage at the branch entrance of the conductive branch 1 to n, and is the sum of the currents in conductive branches 1 to n;

[0028] according to and The first calculation formula is obtained:

[0029] ;

[0030] according to and The second calculation formula is obtained:

[0031] ;

[0032] in, The total insulation resistance value of the conductive branches 1 to n in parallel is represented as the first insulation resistance value; Indicates the capacitance value, Indicates the reactance value;

[0033] Combine the first calculation formula and the second calculation formula to obtain the first insulation resistance value The expression:

[0034] ; .

[0035] Furthermore, when in fault tracing mode, the signal analysis and logic processor obtains the actual wiring mode of the user's substation through a fixed monitoring device;

[0036] The signal analysis and logic processor sends a request to the fixed monitoring device to upload voltage and current data of a specified time period;

[0037] The fixed monitoring device collects voltage data and current data of each conductive branch in a specified period according to the voltage and current data request; and sends the voltage data and current data to the portable insulation detection device;

[0038] The signal analysis and logic processor calculates the second insulation resistance value of each conductive branch in a specified time period based on the actual wiring mode, voltage data and current data; compares the second insulation resistance value with the insulation resistance reference threshold based on the grounding resistance type fault analysis algorithm; if the second insulation resistance value is less than the insulation resistance reference threshold, and the duration of the second insulation resistance value being less than the insulation resistance reference threshold is greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch has an internal fault that is not removed in time and the power grid has tripped at a higher level; if the second insulation resistance value is not less than the insulation resistance reference threshold, or the duration of the second insulation resistance value being less than the insulation resistance reference threshold is not greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch does not have an internal fault that is not removed in time and the power grid has tripped at a higher level.

[0039] In a second aspect, a method for safety control of the grid-connected side of a high-voltage user of a power grid is provided, which is applied to the grid-connected side safety control system of any one of the first aspects, wherein the grid-connected side safety control system comprises a portable insulation detection device and a fixed monitoring device; the portable insulation detection device is connected to the coupling point between the user substation and the power grid, and the fixed monitoring device is installed in the user substation to monitor the actual wiring mode of the user substation and the voltage and current data of each conductive branch; a communication connection is established between the portable insulation detection device and the fixed monitoring device, and the method comprises:

[0040] The portable insulation detection device selects insulation detection mode or fault tracing mode;

[0041] When in insulation test mode, the portable insulation test device injects preset harmonic current into the user's substation side;

[0042] Harmonic voltage and harmonic current are collected through a fixed monitoring device, and a first insulation resistance value is calculated based on the harmonic voltage and harmonic current; based on the inherent safety check logic and the first insulation resistance value, it is determined whether the grounding wire is not removed;

[0043] When in fault tracing mode, the portable insulation detection device obtains the actual wiring mode of the user's substation through the fixed monitoring device; the fixed monitoring device collects the voltage and current data of each conductive branch in the specified time period;

[0044] The second insulation resistance value of each conductive branch in a specified time period is calculated based on the actual wiring method, voltage data and current data; based on the grounding resistance type fault analysis algorithm and the second insulation resistance value, it is determined whether there is a grid over-tripping situation caused by the failure to eliminate an internal fault in the user substation in a timely manner.

[0045] The beneficial effects achieved by the present invention are:

[0046] The portable insulation detection device selects an insulation detection mode or a fault tracing mode. When in the insulation detection mode, the portable insulation detection device injects a preset harmonic current into the user substation side. The harmonic voltage and harmonic current are collected through a fixed monitoring device, and a first insulation resistance value is calculated based on the harmonic voltage and harmonic current. Based on the inherent safety verification logic and the first insulation resistance value, it is determined whether the grounding wire has not been removed. When in the fault tracing mode, the portable insulation detection device obtains the actual wiring method of the user substation through the fixed monitoring device. The fixed monitoring device collects voltage and current data of each conductive branch during a specified period of time. Based on the actual wiring method, voltage data, and current data, a second insulation resistance value of each conductive branch during the specified period of time is calculated. Based on the grounding resistance type fault analysis algorithm and the second insulation resistance value, it is determined whether there is a grid over-tripping situation in the user substation due to the untimely removal of an internal fault. By using the portable insulation detection device and the fixed monitoring device in combination, the portable insulation detection device has two coordination modes: insulation detection mode and fault tracing mode. Through the grid coupling point and the device in the user substation, the grid can achieve safety control and technical control of various operations or scenarios in the user substation. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a structural diagram of the grid-connected side safety management and control system for high-voltage users of the power grid according to the present invention;

[0048] Figure 2 This is the wiring method of the portable insulation detection device for the user substation of the present invention;

[0049] Figure 3 The wiring method of the portable insulation detection device for distributed power plants of the present invention is as follows;

[0050] Figure 4 This is a schematic diagram of the portable insulation resistance detection principle of the present invention;

[0051] Figure 5 This is a structural diagram of the portable insulation detection device of the present invention;

[0052] Figure 6 is a structural diagram of the fixed monitoring device of the present invention;

[0053] Figure 7 This is a flow chart of the grid-connected side safety management and control method for high-voltage users of the power grid according to the present invention. DETAILED DESCRIPTION

[0054] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0055] like Figure 1As shown, an embodiment of the present invention provides a grid-connected side security management and control system for high-voltage users of a power grid, including:

[0056] Portable insulation detection device 101 and fixed monitoring device 102;

[0057] The portable insulation detection device 101 is connected to the coupling point between the user substation and the power grid, and the fixed monitoring device 102 is installed on each conductive branch of the user substation;

[0058] A communication connection is established between the portable insulation detection device 101 and the fixed monitoring device 102;

[0059] A portable insulation detection device 101 is used to select an insulation detection mode or a fault tracing mode;

[0060] When in insulation testing mode, the portable insulation testing device 101 injects a preset harmonic current into the user substation side; the fixed monitoring device 102 receives the harmonic voltage and harmonic current, calculates a first insulation resistance value based on the harmonic voltage and harmonic current, and determines whether the grounding wire is not removed based on the inherent safety check logic and the first insulation resistance value;

[0061] When in fault tracing mode, the portable insulation detection device 101 obtains the actual wiring mode of each conductive branch in the user substation through the fixed monitoring device 102; collects the voltage data and current data of each conductive branch in a specified time period through the fixed monitoring device 102; calculates the second insulation resistance value of each conductive branch in the specified time period based on the actual wiring mode, voltage data and current data; and judges whether there is a grid over-tripping situation caused by the failure to remove an internal fault in time in the user substation based on the grounding resistance type fault analysis algorithm and the second insulation resistance value.

[0062] The specific wiring method of the portable insulation detection device is as follows Figure 2 and Figure 3 As shown, Figure 2 The wiring method of the portable insulation detection device for the user's substation, Figure 3 This is the wiring method for a portable insulation test device in a distributed power plant. The injection power output of the portable insulation test device is connected to a set of phased line hook-type sensors via a cable. The external power is then injected into the power grid system or power plant through the line hook-type sensors. The three single-phase line hooks are connected to the overhead line or cable head at the coupling point, depending on the coupling point.

[0063] The schematic diagram of portable insulation resistance test is as follows Figure 4As shown in the figure, conductive branch 1, branch 2, ..., branch n represent the main conductive branches of the user substation, including high-voltage line branches, transformer branches, busbar branches, etc.; considering the presence of distributed capacitance in line branches and the possible presence of reactive power compensation equipment in busbar branches, the equivalent branches contain capacitance components; also considering that transformer branches and line branches contain large inductance components, the equivalent branches also contain inductance components; Es in the figure represents the power supply voltage generated by the portable insulation test device; the sampling resistor Rs represents the internal resistance of the portable insulation test device, which is used to collect current;

[0064] like Figure 5 The figure shows the structure of a portable insulation detection device, which includes a harmonic drive control module, a harmonic generator, a signal analysis and logic processing module, a first communication module, a line connection part, and a first human-machine interaction module. The line connection part is a hook-type sensor, which is fixed to the coupling point via a clamp-type contact and self-locking structure. The harmonic drive control module includes a battery unit, an isolation unit, and a dual-frequency power output unit. The signal analysis and logic processing module includes a charging unit, a signal analysis and logic processor, and a first current and voltage detection unit. The first human-machine interaction module includes a first key input unit and a first display unit.

[0065] Figure 6 The structure of the fixed monitoring device is shown in the figure. It includes a monitoring logic configuration module, a signal acquisition and logic processing module, a second communication module, and a second human-machine interaction module. The monitoring logic configuration module includes a virtual monitoring point configuration unit and a wiring mode maintenance unit. The virtual monitoring point configuration unit is used to configure virtual monitoring points for monitoring current and voltage. The signal acquisition and logic processing module includes a device status verification unit, a signal acquisition and logic processor, and a second current and voltage detection unit. The second human-machine interaction module includes a second key input unit, a second display unit, and a voice and alarm unit. The monitoring logic configuration module creates a typical template for commonly used distributed power supply wiring and typical 35-110 kV substation wiring. Based on the actual wiring mode and conductive branch conditions of the user's substation, the typical template is modified to configure the locations of virtual monitoring points on the main conductive branches and clearly define the voltage transformer and current transformer from which the voltage and current are collected.

[0066] After the hook-type sensor of the portable insulation detection device is connected to the coupling point, confirm whether it is firmly connected to the metal conductive part of the overhead line or cable head, and confirm that no one is working on the power grid line and the conductive equipment on the user side;

[0067] The portable insulation detection device is powered on, and the first current and voltage detection unit obtains the test current and test voltage of the hook-type sensor at the coupling point;

[0068] The signal analysis and logic processor determines whether the harmonic output meets the requirements based on the test current and test voltage. If it meets the requirements, it is determined that the self-test is qualified; if it does not meet the requirements, it is determined that the self-test is unqualified;

[0069] After the self-test is confirmed to be qualified, the first communication module of the portable insulation detection device and the second communication module of the fixed monitoring device are switched to the preset wireless public network frequency and connected to the power dedicated network APN; and the operator of the designated user substation is notified to adjust the second communication module of the fixed monitoring device to connect to the power dedicated APN and pair with the portable insulation detection device;

[0070] The first human-machine interaction module selects the insulation detection mode or the fault tracing mode according to the mode instruction input by the operator in the first key input unit;

[0071] The dual-frequency and amplitude parameters of the harmonic drive control module are set to generate trigger pulses that are sent to the isolation unit, thereby controlling the inverter to generate dual-frequency power output. The inverter is powered by a battery, the output is inverted by a MOS tube, and then filtered by an inductor and capacitor to output three-phase AC. After the harmonic generation is stable, 20 cycles of harmonics are continuously injected into the grid.

[0072] The signal analysis and logic processor obtains the first frequency based on the injection dual-frequency method Time harmonic voltage and harmonic currents and the second frequency Time harmonic voltage and harmonic currents , and is the voltage at the branch entrance of the conductive branch 1 to n, and is the sum of the currents in conductive branches 1 to n;

[0073] according to and The first calculation formula is obtained:

[0074] ;

[0075] according to and The second calculation formula is obtained:

[0076] ;

[0077] in, The total insulation resistance value of the conductive branches 1 to n in parallel is represented as the first insulation resistance value; Indicates the capacitance value, Indicates the reactance value;

[0078] The first frequency is specifically 200 Hz, and the second frequency is specifically 400 Hz;

[0079] Combine the first calculation formula and the second calculation formula to obtain the first insulation resistance value The expression:

[0080] ; ;

[0081] The insulation resistance part indicates the grounding performance. When the grounding wires are not removed, the equivalent insulation resistance value is below 4 ohms. If all grounding wires are removed, the insulation resistance value will be much greater than 4 ohms, reaching the megaohm level. Therefore, 4 ohms can be used as the reference threshold for insulation resistance.

[0082] If the first insulation resistance value is less than the insulation resistance reference threshold, it is determined that the grounding wire has not been removed; the operator of the user substation is notified to check the removal of the grounding wire in detail;

[0083] If the first insulation resistance value is not less than the insulation resistance reference threshold, it is determined that the grounding wire is not removed; a test report is generated, the portable insulation detection device is turned off, the hook-type sensor is removed, and the coupling point is restored to a normal state;

[0084] When in fault tracing mode, the signal analysis and logic processor obtains the actual wiring mode of each conductive branch in the user's substation through a fixed monitoring device;

[0085] The signal analysis and logic processor sends a request to the fixed monitoring device to upload voltage and current data of a specified time period;

[0086] The fixed monitoring device collects voltage data and current data of each conductive branch in a specified period according to the voltage and current data request; and sends the voltage data and current data to the portable insulation detection device;

[0087] The signal analysis and logic processor calculates the second insulation resistance value of each conductive branch in a specified time period based on the actual wiring mode, voltage data and current data; compares the second insulation resistance value with the insulation resistance reference threshold based on the grounding resistance fault analysis algorithm; if the second insulation resistance value is less than the insulation resistance reference threshold, and the duration of the second insulation resistance value being less than the insulation resistance reference threshold is greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch has an internal fault that is not removed in time and the power grid has tripped at a higher level; if the second insulation resistance value is not less than the insulation resistance reference threshold, or the time that the second insulation resistance value is less than the insulation resistance reference threshold is not greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch does not have an internal fault that is not removed in time and the power grid has tripped at a higher level.

[0088] The beneficial effects of the embodiments of the present invention are:

[0089] By adopting the combination of portable insulation detection devices and fixed monitoring devices, it has two coordination modes: insulation detection mode and fault tracing mode. Through the grid coupling point and the device in the user's substation, the grid can realize the safety management and technical control of various operations or scenarios in the user's substation.

[0090] In combination with the grid-connected side safety management and control system for high-voltage users of the power grid described in the above embodiments, the grid-connected side safety management and control method for high-voltage users of the power grid is described below through an embodiment.

[0091] like Figure 7 As shown, an embodiment of the present invention provides a method for grid-connected side security management and control of high-voltage users of a power grid, including:

[0092] 701, the portable insulation detection device selects insulation detection mode or fault tracing mode;

[0093] 702, when in insulation detection mode, the portable insulation detection device injects a preset harmonic current into the user substation side;

[0094] 703. Receive the harmonic voltage and harmonic current through a fixed monitoring device, calculate a first insulation resistance value based on the harmonic voltage and harmonic current, and determine whether the grounding wire is not removed based on the inherent safety check logic and the first insulation resistance value.

[0095] 704. When in fault tracing mode, the portable insulation detection device obtains the actual wiring mode of each conductive branch in the user substation through the fixed monitoring device; the fixed monitoring device collects voltage data and current data of each conductive branch in a specified time period;

[0096] 705. Calculate the second insulation resistance value of each conductive branch in a specified time period based on the actual wiring mode, voltage data, and current data; and determine whether there is a grid over-tripping situation caused by untimely internal fault removal in the user substation based on the grounding resistance type fault analysis algorithm and the second insulation resistance value.

[0097] The beneficial effects of the embodiments of the present invention are:

[0098] In the process of the above steps 701 to 705, by adopting the combination of a portable insulation detection device and a fixed monitoring device, two cooperation modes, namely insulation detection mode and fault tracing mode, are provided. By cooperating with the devices in the user substation through the grid coupling point, the grid can realize the safety control and technical control of various operations or scenarios of the user substation.

[0099] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0100] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0101] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0102] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0103] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A grid-connected high-voltage user safety management and control system, characterized in that: include: Portable insulation testing devices and fixed monitoring devices; The portable insulation detection device is connected to the coupling point between the user substation and the power grid, and the fixed monitoring device is installed in the user substation to monitor the actual wiring mode of the user substation and the voltage and current data of each conductive branch; a communication connection is established between the portable insulation detection device and the fixed monitoring device; The portable insulation detection device is used to select an insulation detection mode or a fault tracing mode; When in the insulation detection mode, the portable insulation detection device injects a preset harmonic current into the user substation side; the harmonic voltage and harmonic current are collected through the fixed monitoring device, a first insulation resistance value is calculated based on the harmonic voltage and the harmonic current, and a determination is made based on the inherent safety check logic and the first insulation resistance value whether the grounding wire is not removed; When in the fault tracing mode, the portable insulation detection device obtains the actual wiring mode of the user substation through the fixed monitoring device; and collects voltage data and current data of each conductive branch in a specified period of time through the fixed monitoring device; Calculate the second insulation resistance value of each conductive branch in the specified time period according to the actual wiring mode, the voltage data, and the current data; Based on the grounding resistance fault analysis algorithm and the second insulation resistance value, it is determined whether there is a grid over-tripping situation caused by the failure to clear an internal fault in time in the user substation.

2. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 1 is characterized in that: The portable insulation detection device includes a harmonic drive control module, a harmonic generator, a signal analysis and logic processing module, a first communication module, a line connection part and a first human-computer interaction module; The line hanging part is a hook-type sensor, and the hook-type sensor is fixed to the coupling point through a clamp-type contact and a self-locking structure; The harmonic drive control module includes a battery unit, an isolation unit and a dual-frequency power output unit; The signal analysis and logic processing module includes a charging unit, a signal analysis and logic processor and a first current and voltage detection unit; The first human-computer interaction module includes a first key input unit and a first display unit.

3. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 2 is characterized in that: The fixed monitoring device includes a monitoring logic configuration module, a signal acquisition and logic processing module, a second communication module and a second human-computer interaction module; The monitoring logic configuration module includes a virtual monitoring point configuration unit and a wiring mode maintenance unit; the virtual monitoring point configuration unit is used to configure virtual monitoring points for monitoring current and voltage; The signal acquisition and logic processing module includes a device status verification unit, a signal acquisition and logic processor, and a second current and voltage detection unit; The second human-computer interaction module includes a second key input unit, a second display unit and a voice and alarm unit.

4. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 3 is characterized in that: When the hook-type sensor is connected to the coupling point, the portable insulation detection device is powered on, and the first current and voltage detection unit obtains the test current and test voltage of the hook-type sensor at the coupling point; The signal analysis and logic processor determines whether the harmonic output meets the requirements based on the test current and the test voltage. If it meets the requirements, it is determined that the self-test is qualified; if it does not meet the requirements, it is determined that the self-test is unqualified.

5. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 4 is characterized in that: When it is determined that the self-test is qualified, the first communication module of the portable insulation detection device and the second communication module of the fixed monitoring device are switched to a preset wireless public network frequency and connected to the power dedicated network.

6. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 5 is characterized in that: The first human-computer interaction module is used to select an insulation detection mode or a fault tracing mode according to a mode instruction input by an operator in the first key input unit.

7. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 6 is characterized in that: When in the insulation detection mode, the harmonic drive control module generates a harmonic generation control signal according to the insulation detection requirement; The harmonic generator generates a preset harmonic current of a target frequency according to the harmonic generation control signal, and injects the preset harmonic current into the user substation side at the coupling point through the hook-type sensor; The fixed monitoring device collects harmonic voltage and harmonic current at the virtual monitoring point of each conductive branch through the signal acquisition and logic processing module; and sends the harmonic voltage and harmonic current to the first communication module of the portable insulation detection device through the second communication module; The signal analysis and logic processor calculates a first insulation resistance value based on the harmonic voltage and the harmonic current, and compares the first insulation resistance value with an insulation resistance reference threshold based on an inherent safety check logic. If the first insulation resistance value is less than the insulation resistance reference threshold, it is determined that the grounding wire has not been removed; if the first insulation resistance value is not less than the insulation resistance reference threshold, it is determined that the grounding wire has not been removed.

8. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 7 is characterized in that: The signal analysis and logic processor obtains a first frequency based on an injection dual-frequency method Time harmonic voltage and harmonic currents and the second frequency Time harmonic voltage and harmonic currents , and the aforementioned is the voltage at the branch entrance of the conductive branch 1 to n, and the aforementioned is the sum of the currents of the conductive branches 1 to n; According to the and the aforementioned The first calculation formula is obtained: ； According to the and the aforementioned The second calculation formula is obtained: ； Among them, the represents the total insulation resistance value of the conductive branches 1 to n in parallel as the first insulation resistance value; Indicates the capacitance value, the Indicates the reactance value; The first insulation resistance value is obtained by combining the first calculation formula and the second calculation formula. The expression: ； 。 9. The grid-connected side safety management and control system for high-voltage users of the power grid according to claim 6 is characterized in that: When in the fault tracing mode, the signal analysis and logic processor obtains the actual wiring mode of the user substation through the fixed monitoring device; The signal analysis and logic processor sends a request to the fixed monitoring device to upload voltage and current data of a specified time period; The fixed monitoring device collects voltage data and current data of each conductive branch in the specified time period according to the voltage and current data request; sending the voltage data and the current data to the portable insulation detection device; The signal analysis and logic processor calculates the second insulation resistance value of each conductive branch in the specified time period according to the actual wiring mode, the voltage data and the current data; Based on the grounding resistance type fault analysis algorithm, the second insulation resistance value is compared with the insulation resistance reference threshold. If the second insulation resistance value is less than the insulation resistance reference threshold, and the duration of the second insulation resistance value less than the insulation resistance reference threshold is greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch has an internal fault that is not removed in time, resulting in a grid over-tripping situation; if the second insulation resistance value is not less than the insulation resistance reference threshold, or the duration of the second insulation resistance value less than the insulation resistance reference threshold is not greater than the protection setting action time of the corresponding conductive branch, it is determined that the corresponding conductive branch does not have an internal fault that is not removed in time, resulting in a grid over-tripping situation.

10. A method for safety management and control of the grid-connected side of a high-voltage user of a power grid, characterized in that: A grid-connected side safety management and control system for high-voltage users of a power grid, as described in any one of claims 1 to 9, comprising a portable insulation detection device and a fixed monitoring device; the portable insulation detection device is connected to a coupling point between a user substation and power transmission of the power grid, and the fixed monitoring device is installed in the user substation to monitor the actual wiring mode of the user substation and the voltage and current data of each conductive branch; Establishing a communication connection between the portable insulation detection device and the fixed monitoring device, the method includes: The portable insulation detection device selects an insulation detection mode or a fault tracing mode; When in the insulation detection mode, the portable insulation detection device injects a preset harmonic current into the user substation side; Receiving harmonic voltage and harmonic current through the fixed monitoring device, calculating a first insulation resistance value based on the harmonic voltage and the harmonic current; and determining whether a grounding wire has not been removed based on inherent safety check logic and the first insulation resistance value; When in the fault tracing mode, the portable insulation detection device obtains the actual wiring mode of the user substation through the fixed monitoring device; and collects voltage data and current data of each conductive branch in a specified period of time through the fixed monitoring device; The second insulation resistance value of each conductive branch in the specified time period is calculated based on the actual wiring method, the voltage data and the current data; based on the grounding resistance type fault analysis algorithm and the second insulation resistance value, it is determined whether there is a grid over-tripping situation caused by the failure to timely eliminate an internal fault in the user substation.

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