A control device and method for black start of a hydroelectric unit supplying power to a factory when a line trips

Abstract

The invention discloses a control device for a black start of a hydropower unit supplying power to a plant when a line trips, comprising a power supply module, a circuit breaker position detection module, a main control module and a trip module; the device detects the tripping of the line circuit breaker through the circuit breaker position detection module and transmits a signal to the main control module; the main control module then determines the number of operating units in the hydropower station by detecting the positions of the circuit breakers of each unit connected to the power grid through the circuit breaker position detection module; when the line trips, only one unit is retained among the operating units, and the circuit breakers of the other operating units are disconnected from the power grid through the trip module, so as to ensure the operation of one unit in the hydropower station, realize the line tripping, and still retain one unit in the hydropower station for isolated grid operation, and operate in an isolated island with its own power for plant use, waiting for the power grid dispatching order to quickly implement the black start and send out the power; the invention can shorten the black start preparation time and ensure the safety of the plant system.

Description

Technical Field

[0001] The invention belongs to the technical field of black start, and in particular relates to a black start control device and method for a hydroelectric generator set supplying power to a plant when a line trips. Background Art

[0002] The AC power supply system maintains a balance between power generation and power consumption in real time. In the event of an accident, the balance between supply and demand is disrupted, which may cause a power outage in the entire network. The restart of the power grid will require the support of a black start. Therefore, in order to cope with extreme situations, the power grid must consider various possible technologies for rapid transmission after power failure. When the transmission line of a hydropower station trips, the units in the hydropower station will generally enter a shutdown state. At this time, if the backup power supply is also without power, the units of the hydropower station will have no power supply, and the auxiliary machines of the hydropower station will stop working. The power outage of the entire station will develop towards unpredictable serious consequences, which is very detrimental to the safety of the main and auxiliary equipment in the entire station. When the power grid line trips, some hydropower stations are transformed so that the hydropower units can be switched to isolated grid operation without stopping when the line trips. However, since the auxiliary machines of the hydropower station are usually small, the power generated by several units cannot be absorbed. At this time, the speed and frequency of each unit will increase rapidly, and finally the hydropower units will compete for power, that is, the power will be positive and negative, and the stable operation of the isolated grid cannot be maintained. Finally, the protection action will cut off the hydropower units, causing the whole plant to lose power. At this time, the hydropower station must designate a hydropower unit to quickly black start, so as to quickly restore the power supply of the plant. However, it usually takes time to start a unit. Therefore, it is necessary to have only one unit in the hydropower station for plant power supply after the line trips, and the other units trip, so that the equipment in the hydropower station can be operated without power loss. At the same time, according to the grid dispatching instructions, the power supply can be quickly sent out again, shortening the black start time. At present, there is no relevant literature on the black start control device and method for the hydropower station line tripping and one hydropower unit for plant power supply. In the future, this direction will also become a popular research direction for black start. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a black start control device and method for supplying power to a plant when a line trips and a hydropower unit is in operation, so that after the hydropower station line trips, one hydropower unit is maintained to operate in an isolated grid with plant power, and power is quickly sent out again in a black start mode according to the grid dispatching instruction, so as to ensure that when the line trips, one hydropower unit is not shut down, and the plant system is powered by one unit. The black start function enriches the black start technical means, can shorten the black start preparation time, and ensures the safety of the plant system.

[0004] The present invention is achieved through the following technical solutions:

[0005] A black start control device for a hydropower unit supplying power to a factory when a line trips, comprising a circuit breaker position detection module, a main control module and a trip module, wherein the input end of the circuit breaker position detection module is connected to the auxiliary contact of the unit circuit breaker, and the output end is connected to the digital input channel of the main control module, the circuit breaker position detection module is used to detect the position state of the circuit breaker of the line and the circuit breaker connecting the unit to the power grid, the digital output end of the main control module is connected to the control port of the trip module, the main control module is used to identify whether the circuit breaker of the line is tripped, and after the circuit breaker of the line is tripped, the state of the circuit breaker connecting each hydropower unit to the power grid is judged, and the trip module is controlled to trip so that only one hydropower unit is kept in operation, and the trip module is used to drive the circuit breaker connecting the hydropower unit to the power grid to trip;

[0006] The circuit breaker position detection module includes a circuit breaker position detection circuit, a first unit circuit breaker detection circuit, a second unit circuit breaker detection circuit, and a third unit circuit breaker detection circuit. The circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the normally closed contacts of the circuit breaker, the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker through a circuit breaker position interface. The output ends of the circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the digital quantity input port of the main control module.

[0007] Preferably, it also includes a power supply module, which adopts a switching power supply that outputs 24V power supply and 5V power supply. The power supply module outputs 24V power supply which is connected to the voltage signal end of the circuit breaker position detection module, and the power supply module outputs 5V power supply which is connected to the power supply ends of the main control module and the tripping module. The power supply module is used to provide a voltage detection signal for the circuit breaker position detection module, and to provide a working power supply for the main control module and the tripping module.

[0008] Preferably, the circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit have the same structure and parameters, and all use a voltage conversion chip with model 7805. One end of the circuit breaker position interface in each circuit of the circuit breaker position detection module is connected to the 24V power supply output by the power supply module, and the other end is connected to different digital input channels of the main control module after passing through the voltage conversion chip. The voltage conversion chip is used to convert the 24V voltage signal into a 5V voltage signal.

[0009] Preferably, the main control module includes a power interface, a capacitor and a processor, the three ports in the power interface are respectively connected to the 24V voltage, 5V voltage and power ground output by the power supply module, the capacitor is connected in parallel to the power input port of the processor, the digital signal input port of the processor is respectively connected to the output ports of the four-way circuit breaker position detection module, and the digital signal output port of the processor is connected to the trip module control voltage signal; the processor has seven digital signal input ports and seven digital signal output ports, of which three digital signal input ports are extended input ports, and four digital signal output ports are extended output ports.

[0010] Furthermore, the processor in the main control module adopts a STC15W201S processor, which has 16 pins, a clock frequency of 13.5 MHz, a Flash program memory of 1 KB, a RAM capacity of 256 B, and an EEPROM capacity of 4 KB.

[0011] Preferably, the tripping module includes a first tripping circuit, a second tripping circuit, and a third tripping circuit, and the control ends of the first tripping circuit, the second tripping circuit, and the third tripping circuit are respectively connected to the digital output channels of the main control module, and the first tripping circuit, the second tripping circuit, and the third tripping output ports are respectively connected to the tripping circuits of the first circuit breaker, the second circuit breaker, and the third circuit breaker.

[0012] Furthermore, the first tripping circuit, the second tripping circuit, and the third tripping circuit have the same structure, and each tripping circuit includes a freewheeling diode, a single-position relay, a transistor, a driving resistor, and a tripping interface. The tripping interface is connected to the normally open contact of the single-position relay, and the relay coil is connected in parallel between the positive 5V output of the power supply module and the ground via the transistor emitter and the relay electrode. The anode of the freewheeling diode is connected to the common point between the relay coil and the transistor emitter, the anode of the freewheeling diode is connected to the positive 5V power supply output of the power supply module, and the base of the transistor is connected to the digital signal output port of the processor via the driving resistor.

[0013] A control method for a black start of a hydropower unit supplying power to a plant when a line trips, based on any one of the above-mentioned devices, comprises the following steps:

[0014] 1) The main control module determines whether the circuit breaker position in the circuit breaker position detection module is in a tripped state. If not, the detection waiting state is maintained until a circuit breaker tripping signal is detected, the trigger device is started, and the process proceeds to step 2);

[0015] 2) The main control module determines the position status of the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker in the circuit breaker position detection module, confirms the number and status of the running units when the circuit breaker trips, and sorts them according to the circuit breaker number, and enters step 3);

[0016] 3) The main control module keeps the first-ranked unit running, controls the circuit breakers of other units to trip through the tripping module, and enters step 4);

[0017] 4) The first-ranked unit leads the hydropower plant's power system to operate in an isolated grid, and according to the grid dispatching instructions, the power supply of this unit is sent to the grid.

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

[0019] The present invention detects the tripping of the circuit breaker through the circuit breaker position detection module and transmits the signal to the main control module. The main control module then detects the position of the circuit breaker connected to the power grid by the circuit breaker position detection module, and determines the number of operating units in the hydropower station. When the line trips, only one unit is retained in the operating units, and the other operating units disconnect the circuit breakers connected to the power grid through the trip module, ensuring the operation of one unit in the hydropower station, realizing the line tripping, and one unit is still retained in the hydropower station to operate in an isolated network, with its own factory power island operation, waiting for the grid adjustment order to quickly implement black start and send out power; by detecting the position of the circuit breaker, it is determined whether the line has tripped, and the main control module is responsible for maintaining the switching of the operating status of one unit. The present invention does not change the normal control mode of the original circuit breaker, and only needs to connect the spare contacts and spare disconnection control channels of the circuit breaker; the channel can be flexibly expanded according to the number of units in the hydropower station, and can be promoted and applied in hydropower and gas turbines.

[0020] Furthermore, the present invention determines the number of operating units after the line trips by monitoring the section positions of the connection between each unit in the hydropower station and the power grid, thereby providing a basis for the main control module to cut off.

[0021] Furthermore, the power supply module of the present invention adopts a switching power supply module with 24V and 5V voltage outputs. The device does not need to be equipped with a separate power supply module, and the ready-made power supply module can ensure continuous and reliable operation of the device.

[0022] Furthermore, when the black start of the present invention sends power to the power grid, there is no need to carry out black start preparation and a series of operation procedures, and the power can be sent at any time, which greatly shortens the black start time.

[0023] Furthermore, the present invention converts the circuit breaker position into a 5V voltage signal compatible with the main control module through a 7805 voltage regulator chip, thereby ensuring the safety of the main control device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a principle block diagram of the device of the present invention.

[0025] Figure 2 This is a circuit diagram of a circuit breaker position detection module of the present invention.

[0026] Figure 3This is the circuit diagram of the main control module of the present invention.

[0027] Figure 4 This is a circuit diagram of the trip module of the present invention.

[0028] In the figure: power supply module 1; circuit breaker position detection module 2; main control module 3; tripping module 4. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0030] The present invention can solve the problem that a plurality of operating units in a hydropower station cannot operate stably when a line trips, provides a device for maintaining power supply to a plant system when a line trips, and has a black start sending function.

[0031] The present invention provides a black start control device for a hydropower unit supplying power to a factory when a line trips. Figure 1 As shown, it includes a circuit breaker position detection module 2, a main control module 3 and a trip module 4. The input end of the circuit breaker position detection module 2 is connected to the auxiliary contact of the unit circuit breaker, and the output end is connected to the digital input channel of the main control module 3. The circuit breaker position detection module 2 is used to detect the position status of the circuit breaker and the circuit breaker connecting the unit to the power grid. The digital output end of the main control module 3 is connected to the control port of the trip module 4. The main control module 3 is used to identify whether the circuit breaker is tripped. After the circuit breaker is tripped, the status of the circuit breaker connecting each hydropower unit to the power grid is judged, and the trip module 4 is controlled to trip so that only one hydropower unit is kept running. The trip module 4 is used to drive the circuit breaker connecting the hydropower unit to the power grid to trip.

[0032] In this embodiment, a power supply module 1 is also included. The power supply module 1 adopts a switching power supply that outputs 24V power supply and 5V power supply. The power supply module 1 outputs 24V power supply and is connected to the voltage signal end of the circuit breaker position detection module 2. The power supply module 1 outputs 5V power supply and is connected to the power supply ends of the main control module 3 and the trip module 4. The power supply module 1 is used to provide a voltage detection signal for the circuit breaker position detection module 2 and to provide a working power supply for the main control module 3 and the trip module 4.

[0033] In this embodiment, Figure 3 As shown, the power supply module 1 outputs a 24V power supply connected to the first pin of the power interface DY1 in the main control module 3, the power supply module 1 outputs a 5V power supply connected to the second pin of the power interface DY1 in the main control module 3, the output ground of the power supply module 1 is connected to the third pin of the power interface DY1, and the power interface DY1 is used to connect the power supply module 1 to the device.

[0034] In this embodiment, the circuit breaker position detection module 2 includes a circuit breaker position detection circuit, a first unit circuit breaker detection circuit, a second unit circuit breaker detection circuit, and a third unit circuit breaker detection circuit. The circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the normally closed contacts of the circuit breaker, the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker through a circuit breaker position interface. The output ends of the circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the digital input port of the main control module 3.

[0035] In this embodiment, the circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit have the same structure and parameters, and all use a voltage conversion chip of model 7805. One end of the circuit breaker position interface in each circuit of the circuit breaker position detection module 2 is connected to the 24V power supply output by the power supply module 1, and the other end is connected to different digital input channels of the main control module 3 after passing through the voltage conversion chip. The voltage conversion chip is used to convert the 24V voltage signal into a 5V voltage signal.

[0036] In this embodiment, Figure 2As shown, the circuit breaker position detection circuit includes a circuit breaker position interface DL1 and a voltage conversion chip G1. The first pin of the circuit breaker position interface DL1 is connected to the first pin of the power interface DY1, the second pin of the circuit breaker position interface DL1 is connected to the first pin of the voltage conversion chip G1, the second pin of the voltage conversion chip G1 is connected to the third pin of the power interface DY1, and the third pin of the voltage conversion chip G1 is connected to the digital input channel of the processor in the main control module 3; the first unit circuit breaker detection circuit includes a first unit circuit breaker position interface DL2 and a voltage conversion chip G2. The first pin of the first unit circuit breaker position interface DL2 is connected to the first pin of the power interface DY1, the second pin of the first unit circuit breaker position interface DL2 is connected to the first pin of the voltage conversion chip G2 The pins of the voltage conversion chip G2 are connected, the second pin of the voltage conversion chip G2 is connected to the third pin of the power interface DY1, and the third pin of the voltage conversion chip G2 is connected to the digital input channel of the processor in the main control module 3; the second unit circuit breaker detection circuit includes a second unit circuit breaker position interface DL3 and a voltage conversion chip G3, the first pin of the second unit circuit breaker position interface DL3 is connected to the first pin of the power interface DY1, the second pin of the second unit circuit breaker position interface DL3 is connected to the first pin of the voltage conversion chip G3, the second pin of the voltage conversion chip G3 is connected to the third pin of the power interface DY1, and the voltage conversion chip G3 Pin 3 is connected to the digital input channel of the processor in the main control module 3; the third unit circuit breaker detection circuit includes a third unit circuit breaker position interface DL4 and a voltage conversion chip G4, pin 1 of the third unit circuit breaker position interface DL4 is connected to pin 1 of the power interface DY1, pin 2 of the third unit circuit breaker position interface DL4 is connected to pin 1 of the voltage conversion chip G4, pin 2 of the voltage conversion chip G4 is connected to pin 3 of the power interface DY1, and pin 3 of the voltage conversion chip G4 is connected to the digital input channel of the processor in the main control module 3.

[0037] In this embodiment, the main control module 3 includes a power interface, a capacitor and a processor. The three ports in the power interface are respectively connected to the 24V voltage, 5V voltage and power ground output by the power supply module 1. The capacitor is connected in parallel to the power input port of the processor. The digital signal input port of the processor is respectively connected to the output port of the four-way circuit breaker position detection module 2, and the digital signal output port of the processor is connected to the control voltage signal of the trip module 4; the processor has seven digital signal input ports and seven digital signal output ports, of which three digital signal input ports are extended input ports and four digital signal output ports are extended output ports.

[0038] In this embodiment, Figure 3As shown, the main control module 3 includes a power interface DY1, a capacitor C1 and a processor CL1, the two ends of the capacitor C1 are connected in parallel between the 6th pin and the 8th pin of the processor CL1, the 6th pin of the processor CL1 is connected to the 2nd pin of the power interface DY1, the 8th pin of the processor CL1 is connected to the 3rd pin of the power interface DY1, the 1st pin of the processor CL1 is connected to the 3rd pin of the voltage conversion chip G1, the 2nd pin of the processor CL1 is connected to the 3rd pin of the voltage conversion chip G2, the 3rd pin of the processor CL1 is connected to the 3rd pin of the voltage conversion chip G3, and the 4th pin of the processor CL1 is connected to the 3rd pin of the voltage conversion chip G4.

[0039] In this embodiment, the processor in the main control module 3 adopts a STC15W201S processor, which has 16 pins, a clock frequency of 13.5MHz, a Flash program memory of 1KB, a RAM capacity of 256B, and an EEPROM capacity of 4KB.

[0040] In this embodiment, the trip module 4 includes a first trip circuit, a second trip circuit, and a third trip circuit. The control ends of the first trip circuit, the second trip circuit, and the third trip circuit are respectively connected to the digital output channels of the main control module 3, and the first trip circuit, the second trip circuit, and the third trip output ports are respectively connected to the trip circuits of the first circuit breaker, the second circuit breaker, and the third circuit breaker.

[0041] In this embodiment, the first tripping circuit, the second tripping circuit, and the third tripping circuit have the same structure. Each tripping circuit includes a freewheeling diode, a single-position relay, a transistor, a driving resistor, and a tripping interface. The tripping interface is connected to the normally open contact of the single-position relay. The relay coil is connected in parallel between the positive 5V output of the power supply module 1 and the ground through the transistor emitter and the relay electrode. The anode of the freewheeling diode is connected to the common point between the relay coil and the transistor emitter. The anode of the freewheeling diode is connected to the positive 5V power supply output of the power supply module 1, and the base of the transistor is connected to the digital signal output port of the processor through the driving resistor.

[0042] In this embodiment, the first tripping circuit includes a freewheeling diode D1, a single-position relay R1, a transistor Q1, a driving resistor RR1, and a tripping interface DK1. One end of the single-position relay R1 coil is connected to the second pin of the power interface DY1, and the other end is connected to the emitter of the transistor Q1. The collector of the transistor Q1 is connected to the third pin of the power interface DY1. The anode of the freewheeling diode D1 is connected to the emitter of the transistor Q1, and the cathode is connected to the second pin of the power interface DY1. The first and second pins of the tripping interface DK1 are respectively connected to the common terminal and the normally open contact of the single-position relay R1, and the base of the transistor Q1 is connected to the 10th pin of the processor CL1 via the driving resistor RR1; the second tripping circuit includes a freewheeling diode D2, a single-position relay R2, a transistor Q2, a driving resistor RR2, and a tripping interface DK2. One end of the single-position relay R2 coil is connected to the second pin of the power interface DY1, and the other end is connected to the transistor Q2 The emitter is connected, the collector of the transistor Q2 is connected to the third pin of the power interface DY1, the anode of the freewheeling diode D2 is connected to the emitter of the transistor Q2, and the cathode is connected to the second pin of the power interface DY1, the first pin and the second pin of the tripping interface DK2 are respectively connected to the common end and the normally open contact of the single-position relay R2, and the base of the transistor Q2 is connected to the 11th pin of the processor CL1 via the driving resistor RR2; the third tripping circuit includes a freewheeling diode D3, a single-position relay R3, a transistor Q3, a driving resistor RR3, and a tripping interface DK3, one end of the single-position relay R3 coil is connected to the second pin of the power interface DY1, and the other end is connected to the emitter of the transistor Q3, and the collector of the transistor Q3 is connected to the power interface DY1 The anode of the freewheeling diode D3 is connected to the emitter of the transistor Q3, and the cathode is connected to the second pin of the power supply interface DY1. The first and second pins of the tripping interface DK3 are respectively connected to the common terminal and the normally open contact of the single-position relay R3. The base of the transistor Q3 is connected to the 12th pin of the processor CL1 via the driving resistor RR3.

[0043] A control method for black start of a hydropower unit supplying power to a factory when a line trips, comprising the following steps:

[0044] 1) The main control module 3 determines whether the circuit breaker position in the circuit breaker position detection module 2 is in a tripped state. If not, the detection waiting state is maintained until a circuit breaker tripping signal is detected, the trigger device is started, and the process proceeds to step 2);

[0045] 2) The main control module 3 determines the position status of the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker in the circuit breaker position detection module 2, confirms the number and status of the running units when the circuit breaker trips, and sorts them according to the circuit breaker number, and enters step 3);

[0046] 3) The main control module 3 keeps the first-ranked unit running, and controls the circuit breakers of other units to trip through the trip module 4, and enters step 4);

[0047] 4) The first-ranked unit leads the hydropower plant's power system to operate in an isolated grid, and according to the grid dispatching instructions, the power supply of this unit is sent to the grid.

[0048] The above is only a preferred embodiment of the patent of the present invention, and does not impose any limitation on the patent of the present invention. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A control method for a hydropower unit supplying power to a factory when a line trips, based on a control device for a hydropower unit supplying power to a factory when a line trips, the device comprising a circuit breaker position detection module (2), a main control module (3) and a trip module (4), wherein the input end of the circuit breaker position detection module (2) is connected to the auxiliary contact of the unit circuit breaker, and the output end is connected to the digital input channel of the main control module (3), the circuit breaker position detection module (2) is used to detect the position state of the circuit breaker of the line and the circuit breaker connecting the unit to the power grid, the digital output end of the main control module (3) is connected to the control port of the trip module (4), the main control module (3) is used to identify whether the circuit breaker of the line is tripped, and after the circuit breaker of the line is tripped, the state of the circuit breaker connecting each hydropower unit to the power grid is judged, and the trip module (4) is controlled to trip so that only one hydropower unit is kept in operation, and the trip module (4) is used to drive the circuit breaker connecting the hydropower unit to the power grid to trip; The circuit breaker position detection module (2) comprises a circuit breaker position detection circuit, a first unit circuit breaker detection circuit, a second unit circuit breaker detection circuit, and a third unit circuit breaker detection circuit. The circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the normally closed contacts of the circuit breaker, the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker through a circuit breaker position interface. The output ends of the circuit breaker position detection circuit, the first unit circuit breaker detection circuit, the second unit circuit breaker detection circuit, and the third unit circuit breaker detection circuit are respectively connected to the digital quantity input port of the main control module (3); The method comprises the following steps: 1) The main control module (3) determines whether the circuit breaker position in the circuit breaker position detection module (2) is in a tripped state. If not, the detection waiting state is maintained until a circuit breaker tripping signal is detected, the trigger device is started, and the process proceeds to step 2); 2) The main control module (3) determines the position status of the first unit circuit breaker, the second unit circuit breaker, and the third unit circuit breaker in the circuit breaker position detection module (2), confirms the number and status of the running units when the circuit breaker trips, and sorts them according to the circuit breaker number, and enters step 3); 3) The main control module (3) keeps the first-ranked unit running, and controls the circuit breakers of other units to trip through the tripping module (4), and then goes to step 4); 4) The first-ranked unit leads the hydropower plant's power system to operate in an isolated grid, and according to the grid dispatching instructions, the power supply of this unit is sent to the grid.

2. The method for controlling a black start of a hydropower unit for supplying power to a factory when a line trips according to claim 1 is characterized in that: It also comprises a power supply module (1), wherein the power supply module (1) adopts a switching power supply that outputs a 24V power supply and a 5V power supply. The 24V power supply output by the power supply module (1) is connected to the voltage signal end of the circuit breaker position detection module (2), and the 5V power supply output by the power supply module (1) is connected to the power supply ends of the main control module (3) and the trip module (4). The power supply module (1) is used to provide a voltage detection signal for the circuit breaker position detection module (2) and to provide a working power supply for the main control module (3) and the trip module (4).

3. The method for controlling a black start of a hydropower unit for supplying power to a factory when a line trips according to claim 1 is characterized in that: The circuit breaker position detection circuit, the first unit breaker detection circuit, the second unit breaker detection circuit, and the third unit breaker detection circuit have the same structure and parameters, and all use a voltage conversion chip of model 7805. One end of the circuit breaker position interface in each circuit of the circuit breaker position detection module (2) is connected to the 24V power supply output by the power supply module (1), and the other end is connected to different digital input channels of the main control module (3) after passing through the voltage conversion chip. The voltage conversion chip is used to convert the 24V voltage signal into a 5V voltage signal.

4. The method for controlling a black start of a hydropower unit for supplying power to a factory when a line trips according to claim 1 is characterized in that: The main control module (3) comprises a power supply interface, a capacitor and a processor, wherein three ports in the power supply interface are respectively connected to a 24V voltage, a 5V voltage and a power ground output by a power supply module (1), the capacitor is connected in parallel to a power supply input port of the processor, a digital signal input port of the processor is respectively connected to output ports of a four-way circuit breaker position detection module (2), and a digital signal output port of the processor is connected to a control voltage signal of a trip module (4); the processor has seven digital signal input ports and seven digital signal output ports, wherein three digital signal input ports are extended input ports and four digital signal output ports are extended output ports.

5. The method for controlling a black start of a hydropower unit supplying power to a factory when a line trips according to claim 4 is characterized in that: The processor in the main control module (3) is a STC15W201S processor, which has 16 pins, a clock frequency of 13.5 MHz, a Flash program memory of 1 KB, a RAM capacity of 256 B, and an EEPROM capacity of 4 KB.

6. The method for controlling a black start of a hydropower unit supplying power to a factory when a line trips according to claim 1 is characterized in that: The trip module (4) comprises a first trip circuit, a second trip circuit and a third trip circuit, wherein the control ends of the first trip circuit, the second trip circuit and the third trip circuit are respectively connected to the digital output channels of the main control module (3), and the first trip circuit, the second trip circuit and the third trip output ports are respectively connected to the trip circuits of the first circuit breaker, the second circuit breaker and the third circuit breaker.

7. The method for controlling a black start of a hydropower unit supplying power to a factory when a line trips according to claim 6 is characterized in that: The first tripping circuit, the second tripping circuit and the third tripping circuit have the same structure. Each tripping circuit comprises a freewheeling diode, a single-position relay, a transistor, a driving resistor and a tripping interface. The tripping interface is connected to the normally open contact of the single-position relay. The relay coil is connected in parallel between the positive 5V output of the power supply module (1) and the ground via the transistor emitter and the relay electrode. The anode of the freewheeling diode is connected to the common point between the relay coil and the transistor emitter. The anode of the freewheeling diode is connected to the positive 5V power supply output of the power supply module (1). The base of the transistor is connected to the digital signal output port of the processor via the driving resistor.

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