A configuration system of a coal mine underground substation based on a shared bus PT

Abstract

The application discloses a coal mine underground substation configuration system based on a shared bus PT, which comprises an explosion-proof and intrinsically safe PT device, a high-voltage switch for an underground substation and a shared bus; the explosion-proof and intrinsically safe PT device is connected to a bus of the coal mine underground substation; the explosion-proof and intrinsically safe PT device measures voltage parameters Ua, Ub, Uc, Un and U0 of the bus of the coal mine underground substation and transmits the voltage parameters to a digital protection device in the high-voltage switch for the underground substation through Ua, Ub, Uc, Un and U0 lines of the shared bus, so as to serve as a measurement and protection basis for the high-voltage switch for the underground substation; the explosion-proof and intrinsically safe PT device reduces 10KV / 6KV voltage in the bus to 127V or 110V and transmits the voltage to the high-voltage switch for the underground substation through 127V and 0V lines of the shared bus, so as to provide power supply for operation and control of the high-voltage distribution device; the coal mine underground substation configuration system based on the shared bus PT can reduce ferromagnetic resonance failure of the high-voltage switch of the coal mine underground substation and reliably improve the accuracy of fault line selection, phase selection and measurement and the consistency of data of the coal mine underground power supply system.

Description

Technical Field

[0001] This invention relates to the field of underground power systems in coal mines. Specifically, it relates to a configuration system for underground substations in coal mines based on a shared busbar (PT). Background Technology

[0002] Underground substations in coal mines are crucial facilities, supplying power to production equipment such as coal mining machines, tunneling machines, and belt conveyors. They also power safety equipment like local ventilation fans and safety monitoring systems. The operational safety of underground substations directly impacts safe production within the coal mine. High-voltage switches (high-voltage distribution devices) are essential equipment in these substations. The PT in a high-voltage switch refers to a high-voltage voltage transformer, which proportionally transforms a high primary voltage to a lower voltage of 110V or 100V. It provides operating and control power for the high-voltage switches and also detects bus voltage and performs metering and protection functions. Currently, most high-voltage switches used in underground coal mine substations adopt mining-grade explosion-proof or mining-grade explosion-proof and intrinsically safe designs. To meet explosion-proof requirements, the explosion-proof enclosures are mostly welded from steel plates of a certain thickness according to regulations. If the size is too large, it will increase the weight and make movement and placement difficult; if the size is too small, it cannot meet the requirements for electrical clearance and creepage distance, let alone meet electromagnetic compatibility requirements. Therefore, the reasonable layout of the internal space of high-voltage switches used in underground substations is crucial to the performance and safety of the switches. Currently, each high-voltage switch in an underground coal mine substation is equipped with a PT device, which greatly increases the occurrence of ferroresonant faults. In addition, the data detected by each switch's internal PT is inconsistent, reducing the accuracy and consistency of fault line selection, phase selection, and metering. Furthermore, the secondary equipment cannot work normally after the existing high-voltage switches lose power, and in the event of a three-phase short circuit, it cannot quickly trip and reliably clear the fault, causing further expansion of the accident.

[0003] Furthermore, each high-voltage switch is equipped with a PT device, which occupies the limited space of the high-voltage switch, increases the size and weight of the switch, and the construction cost of the substation, failing to meet the needs of intelligent construction such as remote control and unmanned operation in coal mine power supply systems. Therefore, there is an urgent need to construct a coal mine underground substation configuration system with shared busbar PT devices. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a coal mine underground substation configuration system based on a shared busbar PT.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A coal mine underground substation configuration system based on a shared bus PT includes an explosion-proof and intrinsically safe PT device, a high-voltage switch for the underground substation, and a shared bus.

[0007] The explosion-proof and intrinsically safe PT device is connected to the busbar of the underground substation in the coal mine. The explosion-proof and intrinsically safe PT device measures the voltage parameters Ua, Ub, Uc, Un and U0 of the busbar of the underground substation and transmits them to the digital protection device in the high-voltage switch used in the underground substation via the Ua line, Ub line, Uc line, Un line and U0 line of the shared bus, as the basis for the measurement and protection of the high-voltage switch used in the underground substation.

[0008] The explosion-proof and intrinsically safe PT device reduces the 10KV / 6KV voltage in the busbar of the underground coal mine substation to 127V or 110V, and then transmits it to the high-voltage switch used in the underground substation via the 127V line and 0V line of the shared bus, providing power for the operation and control of the high-voltage power distribution equipment.

[0009] The above-mentioned coal mine underground substation configuration system based on shared bus PT, the explosion-proof and intrinsically safe PT device is connected to the access control system, lighting system and environmental safety monitoring system of the underground substation via the 127V line and 0V line of the shared bus, and provides power to the access control system, lighting system and environmental safety monitoring system.

[0010] The above-mentioned coal mine underground substation configuration system based on shared busbar PT includes a distribution PT and an energy storage power supply.

[0011] The energy storage power supply includes a battery unit and a control unit; the control unit includes a control board and a display screen; the battery unit includes a battery pack, a detection board, a battery control board, and a bidirectional diode;

[0012] The output of the power distribution PT inputs ~127V to the control unit. Through an AD / DC conversion circuit, one path connects to the charging positive terminal of the battery cell, and the other path connects to the main negative terminal of the battery cell. The ~127V input outputs 24V through a transformer relay, relay board, and AC / DC conversion circuit. The discharging positive terminal of the battery cell outputs ~127V through a current sensor, DC / AC circuit, and relay board. The output of the current sensor connects to the input of the control board, and the output of the control board connects to the display screen to show the charging and discharging status. The control board also connects to the CAN bus and the power supply. The output of the control board connects to the transformer relay.

[0013] The charging positive terminal of the battery cell is connected to the positive terminal of the battery pack via a charging relay and the charging diode of a bidirectional diode; the discharging diode of the bidirectional diode is connected to the discharging positive terminal of the control unit via a discharging relay; the positive and negative terminals of the battery pack are connected to the detection board via voltage sampling lines, and the detection board is connected to the battery control board; the output terminal of the battery control board is connected to the CAN bus, and the output terminal of the battery control board is connected to the power supply; the output terminal of the battery control board is connected to the charging relay and the discharging relay; the negative terminal of the battery pack is connected to the main negative terminal.

[0014] The above-mentioned coal mine underground substation configuration system based on a shared busbar PT includes a charging relay comprising a charging control relay J1 and a charging current transformer H1; and a discharging relay comprising a discharging control relay J2 and a discharging current transformer H2.

[0015] The charging positive terminal of the battery cell is connected to the charging diode terminal of the bidirectional diode D1 via the charging control relay J1 and the charging current transformer H1. The output terminal of the bidirectional diode D1 is connected to pin 1 of the battery pack interface P5 via the switch S1 and the fuse F1, and pin 2 of the battery pack interface P5 is grounded. The discharging diode terminal of the bidirectional diode D1 is connected to the discharging positive terminal of the battery cell via the discharging relay J2 and the discharging current transformer H2. Both the charging relay J1 and the discharging relay J2 are JGX-50FA solid-state relays. Both the charging current transformer H1 and the discharging current transformer H2 are CHB-6MP current transformers.

[0016] The above-mentioned configuration system for an underground coal mine substation based on a shared busbar PT includes a current detection circuit, a battery temperature detection circuit, and a voltage detection circuit in the detection board; an MCU microcontroller and a discharge control circuit are installed in the battery control board; the signal output terminals of the current detection circuit and the battery temperature detection circuit are communicatively connected to the input terminal of the MCU microcontroller; the input terminal of the discharge control circuit is connected to the current transformer H1 and the current transformer H2; the output terminal of the discharge control circuit is communicatively connected to the input terminal of the MCU microcontroller; the input terminal of the voltage detection circuit is connected to the battery pack, and the output terminal of the voltage detection circuit is connected to the battery pack management chip U3 and then to the MCU microcontroller.

[0017] In the above-mentioned coal mine underground substation configuration system based on shared bus PT, pins 4 and 3 of the P9 interface of the current detection circuit are connected to the charging relay J1, and pins 2 and 1 of the P9 interface of the current detection circuit are connected to the discharging relay J2.

[0018] Pin 4 of the P9 interface of the current detection circuit is connected in parallel with pin 3 of the P9 interface of the current detection circuit through diode D20, and then through resistor R45. One path is grounded through resistor R46, and the other path is connected to pin 3 of optocoupler U14. Pin 2 of optocoupler U14 is grounded. Pin 1 of optocoupler U14 is connected to pin 47 of MCU microcontroller. Pin 4 of optocoupler U14 and resistor R41 are connected in series, and pin 1 of optocoupler U14 and resistor R44 are connected in series and then in parallel. One path is connected to 5V voltage through inductor L15, and the other path is grounded through parallel capacitors C72 and C73.

[0019] Pin 1 of the P9 interface of the current detection circuit is connected in parallel with pin 2 of the P9 interface of the current detection circuit through diode D21, and then through resistor R50. One path is grounded through resistor R51, and the other path is connected to pin 3 of optocoupler U15. Pin 2 of optocoupler U15 is grounded. Pin 1 of optocoupler U15 is connected to pin 46 of the MCU microcontroller. The line formed by pin 4 of optocoupler U14 and resistor R47 in series and the line formed by pin 1 of optocoupler U14 and resistor R49 in series are connected in parallel. One path is connected to 5V through inductor L18, and the other path is grounded through parallel capacitors C81 and C82.

[0020] In the above-mentioned configuration system of a coal mine underground substation based on a shared bus PT, the P8 interface of the battery temperature detection circuit is connected to a temperature sensor, which is installed on the electrode of the battery pack. Pin 3 of the P8 interface is grounded, and is connected to pin 62 of the MCU microcontroller after being connected in parallel with pin 2 of the P8 interface of the battery temperature detection circuit through diode D19. Pin 2 of the P8 interface is connected in parallel with pin 1 of the P8 interface through resistor R40. The first path is connected to diode D18 and then to diode D19. The second path is connected to 5V voltage through inductor L13. The third path is grounded after being connected in parallel with capacitors C68 and C69.

[0021] The input of the voltage detection circuit is connected to the battery pack. Through fuse F4, the first path is grounded via resistor R10, then diode D13, and simultaneously grounded via capacitor C4. The second path is connected to the source pin 2 of MOSFET Q4. The drain pin 1 of MOSFET Q4 is connected to CEL_GND1 via a parallel fuse resistor ER7 and fuse circuit ER7, then to fuse F7. The drain pin 1 of MOSFET Q4 is also connected to CELL_GND via a series LED D16 and resistor R16. The gate pin 3 of MOSFET Q4 is connected to the battery pack management chip U3 via resistor R13, and the battery pack management chip U3 is then connected to the MCU microcontroller. The gate pin 3 and source pin 2 of MOSFET Q4 are directly connected via Zener diode D10.

[0022] The above-mentioned configuration system for underground coal mine substations based on shared busbar PT uses an STM32F103VC microcontroller.

[0023] The P7 interface pins 3 and 2 of the discharge control circuit are connected to the input terminal of the charging current transformer H1; the P7 pins 4 and 2 of the discharge control circuit are connected to the input terminal of the discharging current transformer H2.

[0024] One pin 2 of the P7 interface of the discharge control circuit is grounded, and the other pin is connected to 5V voltage through parallel capacitors C70 and C71 and inductor L14; pin 1 of the P7 of the discharge control circuit is connected to 5V ADC voltage after being connected to parallel capacitors C70 and C71.

[0025] The first path of pin 3 of the P7 interface of the discharge control circuit is connected to pin 35 of the MCU microcontroller through resistor R38; the second path is grounded through capacitor C67; the third path is grounded through diode D15; and the fourth path is connected to the 5V ADC voltage through diode D15.

[0026] The first path of pin 4 of the P7 interface of the discharge control circuit is connected to pin 36 of the MCU microcontroller through resistor R33; the second path is grounded through capacitor C64; the third path is grounded through diode D12; and the fourth path is connected to the 5V ADC voltage through diode D13.

[0027] The above-mentioned configuration system for an underground coal mine substation based on a shared busbar PT includes a high-voltage switch (200) comprising a switching power supply, a digital protection device, a 4.2-inch LCD screen, a pyrolysis particle fire detection device, and a surface acoustic wave (SAW) temperature measuring device. The switching power supply provides 24V power and is electrically connected to the digital protection device and the 4.2-inch LCD screen. The digital protection device is communicatively connected to the 4.2-inch LCD screen, and setting parameters are input to the digital protection device via buttons on the 4.2-inch LCD screen. The digital protection device is communicatively connected to both the pyrolysis particle fire detection device and the SAW temperature measuring device. The pyrolysis particle fire detection device provides real-time feedback on changes in the monitored internal pyrolysis particle composition to the digital protection device. The SAW temperature measuring device provides real-time feedback on monitored temperature changes to the digital protection device.

[0028] The above-mentioned configuration system for an underground coal mine substation based on a shared busbar PT connects the output terminals of the underground coal mine substation busbar to the switch position input, energy storage signal input, gas interlock input, open input, close input, disconnector position input, and handcart position input of a digital protection device. The digital protection device provides feedback on the close output, open output, undervoltage output, and close interlock output to protect the high-voltage switch. The digital protection device is equipped with a protection network port and a monitoring network port for connection to an external switch.

[0029] The technical solution of the present invention achieves the following beneficial technical effects:

[0030] Using a coal mine underground substation configuration system based on a shared busbar PT can reduce the occurrence of ferroresonant faults in high-voltage switches in coal mine underground substations. It reliably improves the accuracy and consistency of fault line selection, phase selection, and metering in coal mine underground power supply systems. It effectively prevents secondary equipment from malfunctioning after the substation's high-voltage switches lose power, ensuring that the high-voltage switches can quickly trip and reliably clear faults in the event of a three-phase short circuit, preventing further expansion of faults and impacting coal mine production safety. At the same time, it increases the internal space of the high-voltage switches, ensuring electromagnetic compatibility compliance, reducing the size and weight of the high-voltage switches, and lowering the construction cost of coal mine underground substations, thus meeting the needs of intelligent construction of coal mine power supply systems.

[0031] In addition, the shared busbar PT device can reduce the 10KV / 6KV voltage in the busbar to 127V or 110V, and transmit it to other high-voltage switches in the substation via the shared bus. This provides power for the operation and control of related high-voltage switchgear, as well as for the access control system, lighting system, and environmental safety monitoring system of the underground substation. This saves on the investment in transformer installation in the substation. Furthermore, since the shared busbar PT device has an energy storage function, it can ensure the uninterrupted and reliable operation of each system. Attached Figure Description

[0032] Figure 1 A schematic diagram of the configuration system of an underground coal mine substation based on a shared busbar PT according to the present invention;

[0033] Figure 2 Battery cell control diagram of energy storage power supply;

[0034] Figure 3 Control diagram of the control unit for energy storage power supply;

[0035] Figure 4 Circuit diagram of the charging management circuit;

[0036] Figure 5 Circuit diagram of current detection circuit;

[0037] Figure 6 Circuit diagram of battery temperature detection circuit;

[0038] Figure 7 Circuit diagram of voltage detection circuit;

[0039] Figure 8 Circuit diagram of MCU microcontroller;

[0040] Figure 9 Circuit diagram of the discharge control circuit;

[0041] Figure 10 Circuit diagram of the battery pack management chip;

[0042] Figure 11 Circuit diagram of the high-voltage switch used in underground substations.

[0043] The reference numerals in the figure are as follows: 100-Explosion-proof and intrinsically safe PT device; 200-High voltage switch; 300-Shared bus; 400-Busbar of underground coal mine substation; 500-Access control system; 600-Lighting system; 700-Environmental safety monitoring system. Detailed Implementation

[0044] In this embodiment, an explosion-proof and intrinsically safe PT device is installed in an underground coal mine substation as a shared device within the substation area.

[0045] The explosion-proof and intrinsically safe PT device 100 measures the voltage parameters Ua, Ub, Uc, Un, and U0 of the busbar 400 in the underground coal mine substation. These parameters are transmitted via the Ua, Ub, Uc, Un, and U0 lines of the shared bus 300 to the digital protection device inside the high-voltage switch 200 used in the underground substation, serving as the basis for measurement and protection of the high-voltage switch 200.

[0046] The explosion-proof and intrinsically safe PT device 100 reduces the 10KV / 6KV voltage in the busbar 400 of the underground coal mine substation to 127V or 110V, and transmits it to the high-voltage switch 200 used in the underground substation via the 127V line and 0V line of the shared bus 300, providing power for the operation and control of the high-voltage power distribution equipment.

[0047] Multiple sets of high-voltage switches 200, including high-voltage switch 1, high-voltage switch 2, ..., high-voltage switch n, are installed underground. The PT device in each high-voltage switch is shared within the substation area, eliminating the need for the PT device built into the high-voltage switch itself. This improves measurement accuracy, reduces the occurrence of ferroresonant faults in the high-voltage switch, increases internal space, reduces the size and weight of the high-voltage switch, and lowers manufacturing costs.

[0048] Meanwhile, the explosion-proof and intrinsically safe PT device 100 is connected to the access control system 500, lighting system 600 and environmental safety monitoring system 700 of the underground substation via the 127V and 0V lines of the shared bus 300, providing power to the access control system 500, lighting system 600 and environmental safety monitoring system 700.

[0049] The explosion-proof and intrinsically safe PT device 1 is equipped with an energy storage power supply and a distribution PT. It enables the high-voltage switch to quickly trip and reliably isolate the fault in the event of a three-phase short circuit, preventing further escalation of the fault. During power outages in underground coal mine substations, it provides uninterrupted power supply, ensuring the real-time performance of measurement, protection, and monitoring in the underground substation power supply system. This provides reliable support for remote power restoration, unattended operation, and intelligent power supply after a power outage in underground coal mine substations.

[0050] The explosion-proof and intrinsically safe PT device 1 includes a power distribution PT and an energy storage power supply;

[0051] like Figure 2 and Figure 3 As shown, the energy storage power supply includes a battery unit and a control unit; the control unit includes a control board and a display screen; the battery unit includes a battery pack, a detection board, a battery control board, and a bidirectional diode;

[0052] like Figure 3 As shown, the output of the power distribution PT inputs ~127V to the control unit. Through the AD / DC conversion circuit, one path is connected to the charging positive terminal of the battery cell, and the other path is connected to the total negative terminal of the battery cell. The input ~127V outputs 24V through the transformer relay, relay board, and AC / DC conversion circuit. The discharging positive terminal of the battery cell outputs ~127V through the current sensor, DC / AC circuit, and relay board. The output of the current sensor is connected to the input of the control board, and the output of the control board is connected to the display screen to display the charging and discharging status. At the same time, the control board is connected to the CAN bus and the power supply. The output of the control board is connected to the transformer relay.

[0053] like Figure 2 As shown, the charging positive terminal of the battery cell is connected to the positive terminal of the battery pack via a charging relay and the charging diode of a bidirectional diode; the discharging diode of the bidirectional diode is connected to the discharging positive terminal of the control unit via a discharging relay; the positive and negative terminals of the battery pack are connected to the detection board via voltage sampling lines, and the detection board is connected to the battery control board; the output terminal of the battery control board is connected to the CAN bus, and the output terminal of the battery control board is connected to the power supply; the output terminal of the battery control board is connected to the charging relay and the discharging relay; the negative terminal of the battery pack is connected to the main negative terminal.

[0054] The control unit controls the battery cell to supply power to the battery cell and discharge from the battery cell when needed, outputting a 127V voltage. The control board collects the current signal from the discharge + terminal collected by the current sensor and feeds it back to the control board. In the event of a power failure in the coal mine substation, the control board controls the discharge + terminal to discharge and start the battery cell to supply power.

[0055] The battery unit collects current, voltage, and temperature data of the battery pack through the detection board and feeds it back to the control board, which then manages the charging and discharging of the battery pack.

[0056] The energy storage power supply includes a battery pack, a detection board, a battery control board, and bidirectional diodes. The detection board monitors the thermal and electrical data of individual cells, while the battery control board manages the charging and discharging of individual cells or the battery pack, as well as providing protection and control. The energy storage power supply has an input voltage of 127V and an output voltage of 127V. The battery pack consists of 12 60AH lithium iron phosphate batteries.

[0057] In the battery cell:

[0058] like Figure 4 As shown, the charging relay includes a charging control relay J1 and a charging current transformer H1; the discharging relay includes a discharging control relay J2 and a discharging current transformer H2.

[0059] The charging positive terminal of the battery cell is connected to the charging diode terminal of the bidirectional diode D1 via the charging control relay J1 and the charging current transformer H1. The output terminal of the bidirectional diode D1 is connected to pin 1 of the battery pack interface P5 via the switch S1 and the fuse F1, and pin 2 of the battery pack interface P5 is grounded. The discharging diode terminal of the bidirectional diode D1 is connected to the discharging positive terminal of the battery cell via the discharging relay J2 and the discharging current transformer H2. Both the charging relay J1 and the discharging relay J2 are JGX-50FA solid-state relays. Both the charging current transformer H1 and the discharging current transformer H2 are CHB-6MP current transformers.

[0060] like Figure 5 As shown, a current detection circuit, a battery temperature detection circuit, and a voltage detection circuit are set in the detection board; an MCU microcontroller and a discharge control circuit are set in the battery control board; the signal output terminals of the current detection circuit and the battery temperature detection circuit are communicatively connected to the input terminal of the MCU microcontroller; the input terminal of the discharge control circuit is connected to the detection charging current transformer H1 and the detection discharging current transformer H2; the output terminal of the discharge control circuit is communicatively connected to the input terminal of the MCU microcontroller; the input terminal of the voltage detection circuit is connected to the battery pack, and the output terminal of the voltage detection circuit is connected to the battery pack management chip U3 and then to the MCU microcontroller.

[0061] The detection board is equipped with a current detection circuit, a battery temperature detection circuit, and a voltage detection circuit, which are used to detect the current, voltage, and temperature data of the battery pack and feed them back to the MCU microcontroller and discharge control circuit in the battery control board to realize the charging management, discharging management, protection, and control of individual batteries or battery packs.

[0062] In a current detection circuit, such as Figure 5As shown, pins 4 and 3 of the P9 interface of the current detection circuit are connected to the charging relay J1, and pins 2 and 1 of the P9 interface of the current detection circuit are connected to the discharging relay J2.

[0063] Pin 4 of the P9 interface of the current detection circuit is connected in parallel with pin 3 of the P9 interface of the current detection circuit through diode D20, and then through resistor R45. One path is grounded through resistor R46, and the other path is connected to pin 3 of optocoupler U14. Pin 2 of optocoupler U14 is grounded. Pin 1 of optocoupler U14 is connected to pin 47 of MCU microcontroller. Pin 4 of optocoupler U14 and resistor R41 are connected in series, and pin 1 of optocoupler U14 and resistor R44 are connected in series and then in parallel. One path is connected to 5V voltage through inductor L15, and the other path is grounded through parallel capacitors C72 and C73.

[0064] Pin 1 of the P9 interface of the current detection circuit is connected in parallel with pin 2 of the P9 interface of the current detection circuit through diode D21, and then through resistor R50. One path is grounded through resistor R51, and the other path is connected to pin 3 of optocoupler U15. Pin 2 of optocoupler U15 is grounded. Pin 1 of optocoupler U15 is connected to pin 46 of the MCU microcontroller. The line formed by pin 4 of optocoupler U14 and resistor R47 in series and the line formed by pin 1 of optocoupler U14 and resistor R49 in series are connected in parallel. One path is connected to 5V through inductor L18, and the other path is grounded through parallel capacitors C81 and C82.

[0065] The P9 interface of the current detection circuit is connected to the charging relay J1 and the discharging relay J2 in the charging management circuit to obtain the charging and discharging current data, which is then fed back to the MCU microcontroller. The MCU microcontroller controls the charging and discharging by controlling the charging relay J1 and the discharging relay J2.

[0066] In the battery temperature detection circuit, such as Figure 6 As shown, the P8 interface of the battery temperature detection circuit is connected to the temperature sensor, which is set on the electrode of the battery pack. Pin 3 of the P8 interface is grounded, and is connected to pin 62 of the MCU microcontroller after being connected in parallel with pin 2 of the P8 interface of the battery temperature detection circuit through diode D19. Pin 2 of the P8 interface is connected in parallel with pin 1 of the P8 interface through resistor R40. The first path is connected to diode D18 and then to diode D19. The second path is connected to 5V voltage through inductor L13. The third path is grounded after being connected in parallel with capacitors C68 and C69.

[0067] Temperature sensors are installed at the electrodes of the battery pack, and the P8 interface of the battery temperature detection circuit transmits the temperature data collected by the temperature sensors to the MCU microcontroller.

[0068] In voltage detection circuits, such as Figure 7 As shown, the input terminal of the voltage detection circuit is connected to the battery pack. Through fuse F4, the first path is grounded via resistor R10, then diode D13, and simultaneously grounded via capacitor C4. The second path is connected to the source leg 2 of MOSFET Q4. The drain leg 1 of MOSFET Q4 is connected to CEL_GND1 via a parallel fuse resistor ER7 and fuse circuit ER7, then to fuse F7. The drain leg 1 of MOSFET Q4 is also connected to CELL_GND via a series LED D16 and resistor R16. The gate leg 3 of MOSFET Q4 is connected to the battery pack management chip U3 via resistor R13, and the battery pack management chip U3 is then connected to the MCU microcontroller. The gate leg 3 and source leg 2 of MOSFET Q4 are directly connected via Zener diode D10.

[0069] The voltage detection circuit collects voltage data from multiple battery packs and transmits it to the MCU microcontroller via the battery pack management chip U3. The battery pack management chip U3 can manage multiple individual battery cells simultaneously, using the field-effect transistor Q4 and the parallel fuse resistor ER7 and fuse circuit ER8 to balance the voltage within the battery pack.

[0070] The battery control board contains an MCU microcontroller and a discharge control circuit.

[0071] The MCU microcontroller model is STM32F103VC; for example... Figure 8 As shown, this is a high-density, high-performance ARM Cortex-M3 32-bit microcontroller. The MCU analyzes the collected current, voltage, and temperature data and manages the charging and discharging of the battery pack through a discharge control circuit.

[0072] In the discharge control circuit, such as Figure 9 As shown, pins 3 and 2 of the P7 interface of the discharge control circuit are connected to the input terminal of the charging current transformer H1; pins 4 and 2 of the P7 interface of the discharge control circuit are connected to the input terminal of the discharging current transformer H2.

[0073] One pin 2 of the P7 interface of the discharge control circuit is grounded, and the other pin is connected to 5V voltage through parallel capacitors C70 and C71 and inductor L14; pin 1 of the P7 of the discharge control circuit is connected to 5V ADC voltage after being connected to parallel capacitors C70 and C71.

[0074] The first path of pin 3 of the P7 interface of the discharge control circuit is connected to pin 35 of the MCU microcontroller through resistor R38; the second path is grounded through capacitor C67; the third path is grounded through diode D15; and the fourth path is connected to the 5V ADC voltage through diode D15.

[0075] The first path of pin 4 of the P7 interface of the discharge control circuit is connected to pin 36 of the MCU microcontroller through resistor R33; the second path is grounded through capacitor C64; the third path is grounded through diode D12; and the fourth path is connected to the 5V ADC voltage through diode D13.

[0076] like Figure 11 As shown, the high-voltage switch 200 includes a switching power supply, a digital protection device, a 4.2-inch LCD screen, a pyrolysis particle fire detection device, and a surface acoustic wave (SAW) temperature measuring device. The switching power supply provides 24V power and is electrically connected to the digital protection device and the 4.2-inch LCD screen. The digital protection device is communicatively connected to the 4.2-inch LCD screen, and setting parameters are input to the digital protection device via buttons on the 4.2-inch LCD screen. The digital protection device is communicatively connected to both the pyrolysis particle fire detection device and the SAW temperature measuring device. The pyrolysis particle fire detection device provides real-time feedback on changes in the monitored internal pyrolysis particle composition to the digital protection device. The SAW temperature measuring device provides real-time feedback on monitored temperature changes to the digital protection device.

[0077] The output terminals of the underground substation busbar 400 are connected to the switch position input, energy storage signal input, gas interlock input, open input, close input, disconnector position input, and handcart position input of the digital protection device, respectively; the close output, open output, undervoltage output, and close interlock output of the digital protection device provide feedback to protect the high-voltage switch 200.

[0078] By installing a pyrolysis particle fire detection device and a surface acoustic wave temperature measurement device, the changes in the internal pyrolysis particle composition and temperature within the high-voltage switch are monitored. The digital protection device enables electric tripping, electric closing, manual tripping, and manual closing, and supports remote closing and remote tripping functions. See [link to relevant documentation]. Figure 11 The digital protection device can be remotely controlled via buttons on the 4.2-inch LCD screen or via the protection network port and monitoring network port, enabling intelligent zero-time current protection, arc flash protection, short circuit protection, dynamic overcurrent protection, inverse-time overload protection, overvoltage protection, undervoltage protection, phase imbalance protection, and selective leakage protection.

[0079] The specific work process is as follows:

[0080] 1. Install the high-voltage switch 200 and the explosion-proof and intrinsically safe PT device 100 used for underground substation.

[0081] Multiple sets of high-voltage switches 200, high-voltage switch 1, high-voltage switch 2, ..., high-voltage switch n can be installed underground as needed. The PT device in each high-voltage switch is shared as a device within the substation area, which eliminates the need for the PT device built into the high-voltage switch, improves measurement accuracy, reduces the occurrence of ferroresonant faults in the high-voltage switch, increases the internal space of the high-voltage switch, reduces the size and weight of the high-voltage switch, and lowers the manufacturing cost of the high-voltage switch.

[0082] 2. The PT device is equipped with a power distribution PT and an energy storage power supply.

[0083] The energy storage power supply can store energy through battery units and control units. Through the power distribution PT, it is connected to the access control system 500, lighting system 600 and environmental safety monitoring system 700 of the underground substation via the 127V and 0V lines of the shared bus (300). It can provide uninterrupted power supply when the underground substation fails, ensuring the real-time measurement, protection and monitoring of the power supply system of the underground substation. It provides reliable support for remote power restoration, unattended operation and intelligent power supply after the underground substation fails.

[0084] 3. The high-voltage switch 200 is equipped with a switching power supply, digital protection device, 4.2-inch LCD screen, pyrolysis particle fire detection device and surface acoustic wave temperature measurement device.

[0085] The changes in the monitored internal pyrolysis particle composition are fed back in real time through the pyrolysis particle fire detection device.

[0086] The digital protection device; the surface acoustic wave temperature measuring device feeds back the monitored temperature changes to the digital protection device in real time. The digital protection device realizes electric tripping, electric closing, manual tripping, and manual closing, and supports...

[0087] For remote closing and opening functions, please refer to [link / reference]. Figure 11 The digital protection device can be remotely controlled via buttons on the 4.2-inch LCD screen or via the protection network port and monitoring network port, enabling intelligent zero-time current protection, arc flash protection, short circuit protection, dynamic overcurrent protection, inverse-time overload protection, overvoltage protection, undervoltage protection, phase imbalance protection, and selective leakage protection.

[0088] 0. Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A configuration system for underground substations in coal mines based on shared busbar PTs, characterized in that, Includes explosion-proof and intrinsically safe PT device (100), high-voltage switch (200) used for underground substation and shared bus (300). An explosion-proof and intrinsically safe PT device (100) is connected to the busbar (400) of the underground substation in the coal mine. The explosion-proof and intrinsically safe PT device (100) measures the voltage parameters Ua, Ub, Uc, Un and U0 of the busbar (400) of the underground substation and transmits them to the digital protection device in the high-voltage switch (200) used in the underground substation via the Ua line, Ub line, Uc line, Un line and U0 line of the shared bus (300), which serves as the basis for measurement and protection of the high-voltage switch (200) used in the underground substation. The explosion-proof and intrinsically safe PT device (100) reduces the 10KV / 6KV voltage in the busbar (400) of the underground substation in the coal mine to 127V or 110V, and transmits it to the high-voltage switch (200) used in the underground substation via the 127V line and 0V line of the shared bus (300), providing power for the operation and control of the high-voltage power distribution device; The high-voltage switches (200) used in the underground substation are in multiple sets, and the explosion-proof and intrinsically safe PT device (100) is a shared device for multiple sets of high-voltage switches (200) within the substation area.

2. The configuration system for an underground coal mine substation based on a shared busbar PT as described in claim 1, characterized in that, The explosion-proof and intrinsically safe PT device (100) is connected to the access control system (500), lighting system (600) and environmental safety monitoring system (700) of the underground substation via the 127V and 0V lines of the shared bus (300), and provides power to the access control system (500), lighting system (600) and environmental safety monitoring system (700).

3. A coal mine underground substation configuration system based on a shared busbar PT according to claim 1, characterized in that, The explosion-proof and intrinsically safe PT device (100) includes a power distribution PT and an energy storage power supply; The energy storage power supply includes a battery unit and a control unit; the control unit includes a control board and a display screen; the battery unit includes a battery pack, a detection board, a battery control board, and a bidirectional diode; The output of the power distribution PT inputs 127V AC to the control unit. Through an AC / DC conversion circuit, one path connects to the charging positive terminal of the battery cell, and the other path connects to the main negative terminal of the battery cell. The input 127V AC also outputs 24V through a transformer relay, relay board, and AC / DC conversion circuit. The discharging positive terminal of the battery cell and the main negative terminal of the battery cell output 127V AC through a current sensor, DC / AC circuit, and relay board. The output of the current sensor connects to the input of the control board, and the output of the control board connects to the display screen to show the charging and discharging status. The control board is also connected to the CAN bus and the power supply. The output of the control board connects to the transformer relay. The charging positive terminal of the battery cell is connected to the positive terminal of the battery pack via a charging relay and the charging diode of a bidirectional diode; the discharging diode of the bidirectional diode is connected to the discharging positive terminal of the battery cell via a discharging relay; the positive and negative terminals of the battery pack are connected to the detection board via voltage sampling lines, and the detection board is connected to the battery control board; the output terminal of the battery control board is connected to the CAN bus, and the output terminal of the battery control board is connected to the power supply; the output terminal of the battery control board is connected to the charging relay and the discharging relay; the negative terminal of the battery pack is connected to the main negative terminal.

4. A coal mine underground substation configuration system based on a shared busbar PT according to claim 3, characterized in that, The charging relay includes a charging control relay J1 and a charging current transformer H1; the discharging relay includes a discharging control relay J2 and a discharging current transformer H2. The charging positive terminal of the battery cell is connected to the charging diode terminal of the bidirectional diode D1 via the charging control relay J1 and the charging current transformer H1; the output terminal of the bidirectional diode D1 is connected to pin 1 of the battery pack interface P5 via the switch S1 and the fuse F1, and pin 2 of the battery pack interface P5 is grounded; the discharging diode terminal of the bidirectional diode D1 is connected to the discharging positive terminal of the battery cell via the discharging control relay J2 and the discharging current transformer H2; both the charging control relay J1 and the discharging control relay J2 are JGX-50FA solid-state relays; both the charging current transformer H1 and the discharging current transformer H2 are CHB-6MP current transformers.

5. A coal mine underground substation configuration system based on a shared busbar PT according to claim 4, characterized in that, The detection board is equipped with a current detection circuit, a battery temperature detection circuit, and a voltage detection circuit; the battery control board is equipped with an MCU microcontroller and a discharge control circuit; the signal output terminals of the current detection circuit and the battery temperature detection circuit are communicatively connected to the input terminal of the MCU microcontroller; the input terminal of the discharge control circuit is connected to the charging current transformer H1 and the discharging current transformer H2. The output of the discharge control circuit is connected to the input of the MCU microcontroller; the input of the voltage detection circuit is connected to the battery pack, and the output of the voltage detection circuit is connected to the battery pack management chip U3 and then to the MCU microcontroller.

6. A coal mine underground substation configuration system based on a shared busbar PT according to claim 5, characterized in that, Pins 4 and 3 of the P9 interface of the current detection circuit are connected to the charging control relay J1, and pins 2 and 1 of the P9 interface of the current detection circuit are connected to the discharging control relay J2. Pin 4 of the P9 interface of the current detection circuit is connected in parallel with pin 3 of the P9 interface of the current detection circuit through diode D20, and then through resistor R45. One path is grounded through resistor R46, and the other path is connected to pin 3 of optocoupler U14. Pin 2 of optocoupler U14 is grounded. Pin 1 of optocoupler U14 is connected to pin 47 of MCU microcontroller. Pin 4 of optocoupler U14 and resistor R41 are connected in series, and pin 1 of optocoupler U14 and resistor R44 are connected in series and then in parallel. One path is connected to 5V voltage through inductor L15, and the other path is grounded through parallel capacitors C72 and C73. Pin 1 of the P9 interface of the current detection circuit is connected in parallel with pin 2 of the P9 interface of the current detection circuit through diode D21, and then through resistor R50. One path is grounded through resistor R51, and the other path is connected to pin 3 of optocoupler U15. Pin 2 of optocoupler U15 is grounded. Pin 1 of optocoupler U15 is connected to pin 46 of the MCU microcontroller. The line formed by pin 4 of optocoupler U14 and resistor R47 in series and the line formed by pin 1 of optocoupler U14 and resistor R49 in series are connected in parallel. One path is connected to 5V through inductor L18, and the other path is grounded through parallel capacitors C81 and C82.

7. A coal mine underground substation configuration system based on a shared busbar PT according to claim 6, characterized in that, The P8 interface of the battery temperature detection circuit is connected to the temperature sensor, which is set on the electrode of the battery pack. Pin 3 of the P8 interface is grounded, and is connected to pin 62 of the MCU microcontroller through diode D19 and pin 2 of the P8 interface of the battery temperature detection circuit. Pin 2 of the P8 interface is connected to pin 1 of the P8 interface through resistor R40. The first path is connected to diode D18 and then to diode D19. The second path is connected to 5V voltage through inductor L13. The third path is grounded through capacitors C68 and C69 connected in parallel. The input of the voltage detection circuit is connected to the battery pack. Through fuse F4, the first path is grounded via resistor R10, then diode D13, and simultaneously grounded via capacitor C4. The second path is connected to the source pin 2 of MOSFET Q4. The drain pin 1 of MOSFET Q4 is connected to CEL_GND1 via a parallel fuse resistor ER7 and fuse circuit ER7, then to fuse F7. The drain pin 1 of MOSFET Q4 is also connected to CELL_GND via a series LED D16 and resistor R16. The gate pin 3 of MOSFET Q4 is connected to the battery pack management chip U3 via resistor R13, and the battery pack management chip U3 is then connected to the MCU microcontroller. The gate pin 3 and source pin 2 of MOSFET Q4 are directly connected via Zener diode D10.

8. A coal mine underground substation configuration system based on a shared busbar PT according to claim 6, characterized in that, The MCU microcontroller model is STM32F103VC; The P7 interface pins 3 and 2 of the discharge control circuit are connected to the input terminal of the charging current transformer H1; the P7 pins 4 and 2 of the discharge control circuit are connected to the input terminal of the discharging current transformer H2. One pin 2 of the P7 interface of the discharge control circuit is grounded, and the other pin is connected to 5V voltage through parallel capacitors C70 and C71 and inductor L14; pin 1 of the P7 of the discharge control circuit is connected to 5V ADC voltage after being connected to parallel capacitors C70 and C71. The first path of pin 3 of the P7 interface of the discharge control circuit is connected to pin 35 of the MCU microcontroller through resistor R38; the second path is grounded through capacitor C67; the third path is grounded through diode D15; and the fourth path is connected to the 5V ADC voltage through diode D15. The first path of pin 4 of the P7 interface of the discharge control circuit is connected to pin 36 of the MCU microcontroller through resistor R33; the second path is grounded through capacitor C64; the third path is grounded through diode D12; and the fourth path is connected to the 5V ADC voltage through diode D13.

9. A coal mine underground substation configuration system based on a shared busbar PT according to claim 1, characterized in that, The high-voltage switch (200) includes a switching power supply, a digital protection device, a 4.2-inch LCD screen, a pyrolysis particle fire detection device, and a surface acoustic wave (SAW) temperature measuring device. The switching power supply provides 24V power and is electrically connected to the digital protection device and the 4.2-inch LCD screen. The digital protection device is communicatively connected to the 4.2-inch LCD screen, and setting parameters are input to the digital protection device through the buttons on the 4.2-inch LCD screen. The digital protection device is communicatively connected to the pyrolysis particle fire detection device and the SAW temperature measuring device. The pyrolysis particle fire detection device feeds back the changes in the monitored internal pyrolysis particle composition to the digital protection device in real time. The SAW temperature measuring device feeds back the monitored temperature changes to the digital protection device in real time.

10. A coal mine underground substation configuration system based on a shared busbar PT according to claim 9, characterized in that, The output terminals of the busbar (400) of the underground substation in the coal mine are respectively connected to the switch position input, energy storage signal input, gas interlock input, opening input, closing input, disconnector position input, and handcart position input of the digital protection device; the closing output, opening output, undervoltage output, and closing interlock output of the digital protection device provide feedback to protect the high-voltage switch (200); the digital protection device is equipped with a protection network port and a monitoring network port, which are connected to an external switch.

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