Emergency recovery method and equipment for coal mine power supply network

Abstract

The invention relates to the technical field of safe power supply of a power system, in particular to an emergency recovery method and equipment for a coal mine power supply network, and aims to avoid secondary tripping. The emergency recovery method for the coal mine power supply network comprises the following steps: constructing a topological structure chart of the power supply network, and marking a hierarchical relationship of power supply equipment; electrical parameters of each switch loop in the power supply network are obtained in real time through the SCADA system; under the condition that a tripping phenomenon occurs, positioning superior power supply equipment which does not trigger a protection action according to the topological structure diagram, and calculating a load rate of the superior power supply equipment according to the electrical parameters; and when the load rate is less than or equal to the safety threshold, starting the lower-level equipment of the upper-level power supply equipment in sequence according to the topological structure diagram, and dynamically updating the starting interval time. According to the invention, instantaneous overload in the recovery process can be avoided, so that secondary tripping is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of safe power supply in power systems, and particularly to an emergency recovery method and device for a coal mine power supply network. Background Art

[0002] Due to the complex underground environment in a coal mine power supply system, there are flammable and explosive substances such as gas and dust. Moreover, the roadway structure is complex, the power supply lines are long and have many branches, facing many power supply safety challenges. Under the influence of common faults such as equipment aging, overload, and short circuit, or natural disasters, human operation errors and other factors, it is extremely easy to trigger large-area tripping accidents. Once such an accident occurs, the shutdown of the ventilation system will lead to gas accumulation and deterioration of air quality, threatening the lives of miners; the failure of the drainage system to work will cause water accumulation in the mine, damage equipment, and may trigger roadway collapses and interruption of monitoring and communication systems, resulting in the loss of information between the surface and underground, seriously hindering emergency rescue and production command. Therefore, it is crucial to quickly restore power supply after a large-area tripping in a coal mine.

[0003] Traditional emergency power supply path planning mainly relies on manual experience, and dispatchers manually formulate power supply plans according to the power grid topology structure, equipment status, and fault information. However, this method is difficult to detect potential risks in a timely manner and automatically interrupt power supply, which may lead to secondary tripping, thus masking the initial fault characteristics, increasing the difficulty of troubleshooting, and delaying the handling time. Summary of the Invention

[0004] In order to solve the above problems in the prior art, the present invention proposes an emergency recovery method and device for a coal mine power supply network, which can effectively avoid the occurrence of secondary tripping.

[0005] In the first aspect of the present invention, an emergency recovery method for a coal mine power supply network is proposed. The method includes: Construct a topological structure diagram of the power supply network and mark the hierarchical relationship of power supply equipment; Obtain the electrical parameters of each switch loop in the power supply network in real time through a SCADA system (Supervisory Control and Data Acquisition); the electrical parameters include: current and voltage; In the case of a tripping phenomenon, locate the upper-level power supply equipment that has not triggered the protection action according to the topological structure diagram, and calculate the load rate of the upper-level power supply equipment according to the electrical parameters; In the case where the load rate is less than or equal to the safety threshold, start the lower-level equipment of the upper-level power supply equipment in sequence according to the topological structure diagram, and dynamically update the start interval time.

[0006] Preferably, the steps of "in the case of a tripping phenomenon, locating the upstream power supply device at the nearest level according to the topological structure diagram and calculating the load rate of the upstream power supply device according to the electrical parameters" include: In the case of a tripping phenomenon, starting from the tripping switch, retrieve upstream level by level along the topological structure diagram until an upstream power supply device that has not triggered a protection action is found; Calculate the used power and safety capacity of the upstream power supply device according to the electrical parameters, and then calculate the load rate of the upstream power supply device.

[0007] Preferably, the steps of "calculating the used power and safety capacity of the upstream power supply device according to the electrical parameters, and then calculating the load rate of the upstream power supply device" include: Calculate the used power of the upstream power supply device according to the electrical parameters : ; Wherein, respectively represent the current and voltage of the th non-powered-off branch of the upstream power supply device, is the total number of non-powered-off branches of the upstream power supply device; Calculate the safety capacity of the upstream power supply device according to the rated capacity of the upstream power supply device and a preset derating factor : ; Wherein, k is the preset derating factor, is the rated capacity of the upstream power supply device; Calculate the load rate of the upstream power supply device according to the used power and the safety capacity: .

[0008] Preferably, the steps of "in the case where the load rate is less than or equal to the safety threshold, starting the downstream devices of the upstream power supply device in sequence according to the topological structure diagram and dynamically updating the start interval time" include: If the load rate is less than or equal to the safety threshold, calculate the start interval time according to the load rate and a preset basic interval time : ; Wherein, is the preset basic interval time, is the load rate; According to the topological structure diagram, start a subordinate device of the superior power supply device according to the start interval time, and recalculate the load rate and the start interval time according to the electrical parameters obtained in real time; If the load rate exceeds a preset load rate threshold, suspend the start and give an alarm; otherwise, repeat the steps of starting the subordinate device and calculating the load rate and the start interval time until all power supply devices are restored.

[0009] Preferably, the method further includes: Construct a database for storing device parameters; The device parameters include: the rated capacity, voltage level, and topological relationship of each level of power supply device.

[0010] Preferably, use the depth-first search algorithm to locate the superior power supply device that has not triggered a protection action.

[0011] Preferably, the method further includes: Record the tripping position, the load rate, the start interval time, the recovery progress, and the timestamp in real time, and perform visual display to support manual intervention operations.

[0012] In a second aspect of the present invention, an electronic device is further proposed, including a memory and a processor, and a computer program capable of being loaded and executed by the processor as the method described above is stored on the memory.

[0013] In a third aspect of the present invention, a computer-readable storage device is further proposed, storing a computer program capable of being loaded and executed by a processor as the method described above.

[0014] The present invention has the following beneficial effects: When the load rate is less than or equal to the safety threshold, start the subordinate devices in sequence and dynamically update the start interval time, which can avoid instantaneous overload during the recovery process, thus avoiding the occurrence of secondary tripping.

[0015] Introduce the load rate into the calculation formula of the start interval time, so that during the recovery process, as the load rate of the power supply device increases, the start interval time can be gradually increased to minimize the impact of the instantaneous current impact of the newly started device on the power grid. Description of the Drawings

[0016] Figure 1 is a schematic diagram of the main steps of an embodiment of the emergency recovery method for a coal mine power supply network in the present invention; Figure 2 is a schematic diagram of the topological structure associated with the tripping switch in a case of the present invention. Detailed Embodiments

[0017] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] It should be noted that in the description of the present invention, the terms "first" and "second" are only for the convenience of description and do not indicate or imply the relative importance of the devices, elements, or parameters, and thus should not be construed as limiting the present invention. In addition, the term "and / or" in the present invention is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after, unless otherwise specified.

[0020] Figure 1 is a schematic diagram of the main steps of an embodiment of the emergency recovery method for a coal mine power supply network in the present invention. As Figure 1 shown, the recovery method of this embodiment includes: Step S10: Construct a topological structure diagram of the power supply network and mark the hierarchical relationship of power supply equipment.

[0021] Step S20: Obtain the electrical parameters of each switch loop in the power supply network in real time through the SCADA system.

[0022] Among them, the electrical parameters include: current and voltage.

[0023] SCADA (Supervisory Control and Data Acquisition) is the core platform for the intelligentization of the coal mine power supply network, and its design needs to take into account special requirements such as real-time performance, reliability, and explosion-proof safety.

[0024] Step S30: In the case of a tripping phenomenon, locate the upstream power supply equipment that has not triggered the protection action according to the topological structure diagram, and calculate the load rate of the upstream power supply equipment according to the electrical parameters.

[0025] Among them, the upstream power supply equipment may include: transformers, busbars, distribution cabinets, etc.

[0026] Specifically, this step may include steps S31 - S32: Step S31: In the case of a tripping phenomenon, start from the tripping switch and retrieve upstream level by level along the topological structure diagram until an upstream power supply device that has not triggered a protection action is found.

[0027] For example, a depth - first search algorithm can be used for retrieval, and as long as the upstream power supply device at the nearest level to the tripping switch that has not triggered a protection action (i.e., normal power supply) is found.

[0028] Step S32: Calculate the used power and safety capacity of the upstream power supply device based on electrical parameters, and then calculate the load rate of the upstream power supply device.

[0029] Step S32 may include steps S321 - S323: Step S321: Calculate the used power of the upstream power supply device based on electrical parameters (in kVA), as shown in formula (1): (1) Where, respectively represent the current and voltage of the th non - powered - off branch of the upstream power supply device, is the total number of non - powered - off branches of the upstream power supply device.

[0030] Step S322: Calculate the safety capacity of the upstream power supply device based on the rated capacity of the upstream power supply device and a preset derating factor (in kVA), as shown in formula (2): (2) Where, k is the preset derating factor (taken as 0.8 in this embodiment), is the rated capacity of the upstream power supply device.

[0031] Because many devices in the coal mine power supply network are high - power and will generate instantaneous impact current during startup, the preset derating factor in this embodiment is taken as 0.8, aiming to reserve a 20% buffer space for the impact current.

[0032] Step S323: Calculate the load rate of the upstream power supply device based on the used power and the safety capacity, as shown in formula (3): (3) Step S40: In the case where the load rate is less than or equal to the safety threshold (85% in this embodiment), start the downstream devices of the upstream power supply device in sequence according to the topological structure diagram and dynamically update the startup interval time.

[0033] Set a safety threshold for the load rate to prevent the equipment temperature rise from exceeding the standard (when the measured load rate is 85%, the transformer winding temperature ≤ 80 °C).

[0034] Specifically, this step may include steps S41 - S43: Step S41, if the load rate is less than or equal to the safety threshold, calculate the startup interval time according to the load rate and the preset basic interval time , as shown in formula (4): (4) Wherein, is the preset basic interval time, is the load rate.

[0035] Set the basic interval time to balance the power transmission speed and equipment safety, with a default of 15 seconds, which can be adjusted in advance according to the actual on-site situation.

[0036] For example, , then Δt = 15×(1 + 0.8)=27 seconds.

[0037] Step S42, according to the topology structure diagram, start a subordinate device of the superior power supply device at the startup interval time, and recalculate the load rate and startup interval time according to the electrical parameters obtained in real time.

[0038] Devices that affect safety such as drainage pumps and fans can be preferentially started.

[0039] Step S43, if the load rate exceeds the preset load rate threshold, suspend startup and alarm; otherwise, go to step S42 until all power supply devices are restored.

[0040] Example case: Figure 2 is a schematic diagram of the topology structure associated with the trip switch in the case of the present invention. As Figure 2 shown, the 1140V feeder switch K5 in a certain coal mine mining area substation trips, and its superior device is the transformer TR - 202 ( ).

[0041] Execute the following restoration steps: (1) Topological analysis determines that TR - 202 is the superior power supply device.

[0042] (2) Read , calculate .

[0043] (3) Calculate in real time, and then calculate the load rate , and judge , thus power transmission is allowed.

[0044] (4) Calculate the startup interval time Δt = 15×(1 + 0.75) = 26.25 seconds. In actual use, the startup interval can be taken as 26 seconds.

[0045] (5) Start 3 drainage pumps (each 250 kVA) in sequence at 26-second intervals. The full-load rate ≤ 85% throughout the process, and no secondary tripping is triggered.

[0046] In an alternative embodiment, before step S10, it may further include: Step S5: Construct a database for storing device parameters.

[0047] Among them, the device parameters include: the rated capacity, voltage level, and topological relationship of each level of power supply equipment, etc.

[0048] In another alternative embodiment, in the case of a tripping phenomenon, a thread parallel to steps S30 - S40 can also be started to record the tripping location, load rate, startup interval time, recovery progress, and timestamp in real time, and perform visual display, supporting manual intervention operations.

[0049] Although the above steps are described in the above sequential order in the above embodiments, those skilled in the art can understand that in order to achieve the effects of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reversed order, and these simple changes are all within the protection scope of the present invention.

[0050] Further, based on the above method embodiment, the present invention also provides an embodiment of an electronic device. The electronic device of this embodiment includes a memory and a processor, and a computer program capable of being loaded and executed by the processor as described in the above method is stored on the memory.

[0051] Even further, the present invention also provides an embodiment of a computer-readable storage device. A computer program capable of being loaded and executed by a processor as described in the above method is stored in the storage device of this embodiment.

[0052] The computer-readable storage device may include: various media such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs that can store program codes.

[0053] Those skilled in the art should be able to realize that the method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of electronic hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in the form of electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0054] So far, the technical solution of the present invention has been described in combination with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present invention.

Claims

1. A method for emergency restoration of a coal mine power supply network, characterized in that, The method includes: Construct a topological structure diagram of the power supply network and label the hierarchical relationship of power supply equipment; Obtain the electrical parameters of each switch loop in the power supply network in real time through the SCADA system; the electrical parameters include: current and voltage; In the case of a tripping phenomenon, locate the upstream power supply equipment that has not triggered the protection action according to the topological structure diagram, and calculate the load rate of the upstream power supply equipment according to the electrical parameters; In the case where the load rate is less than or equal to the safety threshold, start the downstream equipment of the upstream power supply equipment in sequence according to the topological structure diagram, and dynamically update the start interval time.

2. The emergency recovery method for a coal mine power supply network according to claim 1, characterized in that, The step of "in the case of a tripping phenomenon, locate the nearest upstream power supply equipment upstream of the fault according to the topological structure diagram, and calculate the load rate of the upstream power supply equipment according to the electrical parameters" includes: In the case of a tripping phenomenon, start retrieving upstream level by level from the tripping switch along the topological structure diagram until the upstream power supply equipment that has not triggered the protection action is found; Calculate the used power and safety capacity of the upstream power supply equipment according to the electrical parameters, and then calculate the load rate of the upstream power supply equipment.

3. The emergency recovery method for the coal mine power supply network according to claim 1, wherein The step of "calculate the used power and safety capacity of the upstream power supply equipment according to the electrical parameters, and then calculate the load rate of the upstream power supply equipment" includes: Calculate the used power of the upper-level power supply device according to the electrical parameters : ； Among them, respectively represent the current and voltage of the th non-powered branch of the said upper-level power supply device, is the total number of non-powered branches of the said upper-level power supply device; Calculate the safety capacity of the upper-level power supply device according to the rated capacity of the upper-level power supply device and a preset derating factor : ； Among them, k is the preset derating factor, is the rated capacity of the upper-level power supply equipment; Calculate the load rate of the upstream power supply equipment according to the used power and the safety capacity: 。 4. The emergency recovery method for the coal mine power supply network according to claim 1, wherein, The step of "in the case where the load rate is less than or equal to the safety threshold, start the downstream equipment of the upstream power supply equipment in sequence according to the topological structure diagram, and dynamically update the start interval time" includes: If the load rate is less than or equal to the safety threshold, calculate the start interval time according to the load rate and the preset basic interval time : ； Wherein, is the preset basic interval time, is the load factor; According to the topological structure diagram, start a downstream equipment of the upstream power supply equipment at the start interval time, and recalculate the load rate and the start interval time according to the electrical parameters obtained in real time; If the load rate exceeds the preset load rate threshold, suspend starting and give an alarm; otherwise, repeat the steps of starting the downstream equipment and calculating the load rate and the start interval time until all power supply equipment is restored.

5. The emergency recovery method for a coal mine power supply network according to claim 1, wherein, The method further includes: Construct a database for storing equipment parameters; The equipment parameters include: the rated capacity, voltage level and topological relationship of each level of power supply equipment.

6. The emergency recovery method for a coal mine power supply network according to claim 1, wherein Use the depth-first search algorithm to locate the upstream power supply equipment that has not triggered the protection action.

7. The emergency recovery method for a coal mine power supply network according to claim 1, wherein The method further includes: Record the tripping position, the load rate, the start interval time, the restoration progress and the timestamp in real time, and perform visual display to support manual intervention operations.

8. An electronic device, characterized in that, Including a memory and a processor, and a computer program capable of being loaded and executed by the processor is stored on the memory, and the method is as described in any one of claims 1-7.

9. A computer-readable storage device, characterized in that, Stored with a computer program capable of being loaded and executed by a processor, and the method is as described in any one of claims 1-7.

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