High-voltage direct-current circuit breaker

Abstract

The invention belongs to the technical field of circuit protection equipment, and particularly relates to a high-voltage direct-current circuit breaker, which comprises a circuit breaker main body, a redundant energy consumption unit, a control main board, a protection circuit unit and an external power supply end, and is characterized in that the control main board and the protection circuit unit are arranged in the circuit breaker main body, and the external power supply end supplies power to a load through the protection circuit unit; the redundant energy consumption unit is arranged between the output end of the circuit breaker main body and the input end of the load, the redundant energy consumption unit is electrically connected with the output end of the protection circuit unit, and the output end of the redundant energy consumption unit is electrically connected with the input end of the load. The hybrid switching mode is adopted, emergency circuit protection can be carried out on the load, secondary switching consumption reduction can be carried out when the response of the hybrid switching mode is too slow, the protection effect on the load is improved, stable operation of a power system is ensured, meanwhile, the influence of high temperature on a solid-state switch can be reduced, and on the basis of the temperature, the reliability of the solid-state switch is improved. And personnel are automatically reminded to maintain the circuit breaker.

Description

Technical Field

[0001] The invention belongs to the technical field of circuit protection equipment, and in particular relates to a high-voltage direct current circuit breaker. Background Art

[0002] In modern power systems, high-voltage direct current transmission is widely used due to its advantages such as high efficiency and low loss. As a key equipment, high-voltage direct current circuit breakers are responsible for quickly cutting off the direct current in the event of a fault and protecting the safety of lines and equipment. It ensures the stability and reliability of power transmission and provides a strong guarantee for large-scale power dispatch.

[0003] At present, common high-voltage DC circuit breakers include mechanical high-voltage DC circuit breakers, all-solid-state high-voltage DC circuit breakers, hybrid high-voltage DC circuit breakers, liquid-electric high-voltage DC circuit breakers, etc. Each circuit breaker has its own advantages and disadvantages. For example, mechanical high-voltage DC circuit breakers have low cost but slow breaking speed, and all-solid-state high-voltage DC circuit breakers have fast response speed but large conduction loss. Among them, hybrid high-voltage DC circuit breakers combine the cost advantage of mechanical types with the fast breaking capability of solid-state types. They have low conduction loss, can cut off fault current in a short time, and are not easy to generate arcs. Therefore, they are widely used. For example, a high-voltage DC circuit breaker disclosed in patent announcement number CN103618298B;

[0004] In the power system, the hybrid high-voltage DC circuit breaker undertakes the key circuit protection task. However, when it is in working state for a long time, it will face a series of complex working conditions. For example, the high temperature in the operating environment will accelerate the aging of the electronic components inside the solid-state switch. As the temperature rises, the electron migration phenomenon intensifies, and the performance of the semiconductor material changes, resulting in the performance degradation of the solid-state switch, thereby affecting its response speed. When the control end of the circuit breaker receives a fault signal and sends an instruction to the solid-state switch, due to the slow response of the solid-state switch, the disconnection speed of the mechanical switch working with it will also be affected and slowed down. During this period, part of the overload current cannot be blocked in time and will still flow to the load, weakening the protection effect of the circuit breaker on the load and threatening the stable operation of the power system. Summary of the invention

[0005] The object of the present invention is to provide a high voltage DC circuit breaker in view of the above problems.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A high-voltage DC circuit breaker includes a circuit breaker body, wherein a control main board and a protection circuit unit are arranged inside the circuit breaker body, and an external power supply end supplies power to a load through the protection circuit unit, and further includes:

[0007] A redundant energy consumption unit is arranged between the output end of the circuit breaker body and the input end of the load, the redundant energy consumption unit is electrically connected to the output end of the protection circuit unit, and the output end of the redundant energy consumption unit is electrically connected to the input end of the load;

[0008] A heat dissipation unit is installed on the outer wall of the circuit breaker body, and the heat dissipation unit is connected with the interior of the circuit breaker body, the interior of the heat dissipation unit and the circuit breaker body are both filled with protective gas, and a resistance adjustment mechanism is arranged inside the redundant energy consumption unit;

[0009] The early warning mechanism is arranged inside the heat dissipation unit, the early warning mechanism is electrically connected to the resistance adjustment mechanism, and the resistance adjustment mechanism is electrically connected to the heat dissipation unit.

[0010] Preferably, the protection circuit unit includes a mechanical switch on-off circuit, a solid-state switch switching circuit and an energy consumption circuit. When the circuit is working normally, the external power supply end supplies power to the load through the mechanical switch on-off circuit and the solid-state switch switching circuit. When a circuit fails, the solid-state switch switching circuit performs a switching action to cut off the mechanical switch on-off circuit and disconnect it, and cooperates with the energy consumption circuit to consume the overload current.

[0011] Preferably, the redundant energy consumption unit includes a double-throw switch and a battery assembly, the output end of the mechanical switch on-off circuit is electrically connected to the input end of the double-throw switch, one of the output ends of the double-throw switch is electrically connected to the input end of the load, the other output end of the double-throw switch is electrically connected to the input end of the resistance regulating mechanism, the output end of the resistance regulating mechanism is electrically connected to the input end of the load, the positive and negative ends of the battery assembly are electrically connected to a timing switch and a normally closed switch, respectively, and the timing switch and the normally closed switch are electrically connected to the power supply end of the double-throw switch, the normally closed switch is electrically connected to the solid-state switch switching circuit, when the timing switch is closed, the timing switch will disconnect the power supply circuit of the normally closed switch, and when the normally closed switch is disconnected, the normally closed switch will disconnect the power supply circuit of the timing switch.

[0012] Preferably, the heat dissipation unit includes a circular sleeve fixedly mounted on the outer wall of the circuit breaker body, a removable end plate is mounted on the end of the circular sleeve, a driving motor is mounted on the side wall of the end plate, and the output end of the driving motor is rotatably connected to the side wall of the end plate, fan blades are arranged inside the circular sleeve, and the output end of the driving motor drives the fan blades to rotate, a plurality of air inlet pipes are fixedly plugged into the side wall of the circuit breaker body located inside the circular sleeve, a side wall of the circuit breaker body away from the circular sleeve is fixedly connected to a reflow cover, and a group of external circulation heat dissipation pipes are fixedly connected between the reflow cover and the circular sleeve, and the driving motor is electrically connected to the control main board.

[0013] Preferably, the resistance adjustment mechanism includes a magnetic isolation hollow plate arranged on the side wall of the circuit breaker body, a left insulating column is fixedly installed inside the magnetic isolation hollow plate, and a resistor rod is fixedly installed at the end of the left insulating column, the end of the resistor rod away from the right insulating column is installed with a right insulating column together with the magnetic isolation hollow plate, an electromagnetic push rod is fixedly installed inside the magnetic isolation hollow plate, and an insulating push block is installed at the telescopic end of the electromagnetic push rod, a conductive slip ring is fixedly inserted on the side wall of the insulating push block, and the conductive slip ring is in sliding contact with the rod wall of the resistor rod, the control main board controls the operation of the electromagnetic push rod according to the strength of the fault signal input, and the output end of the double-throw switch is electrically connected to the input end of the load through the end of the resistor rod close to the left insulating column and the conductive slip ring.

[0014] Preferably, the early warning mechanism includes a temperature detection probe detachably plugged into the end face of the circuit breaker body, and the detection end of the temperature detection probe is arranged inside the circuit breaker body, the control main board controls the operation of the electromagnetic push rod according to the electrical signal output by the temperature detection probe, the end of the resistance rod close to the right insulating column is electrically connected to the drive motor through a conductive slip ring and the control main board, a photoelectric switch is installed on the outer wall of the circuit breaker body at a position inside the circular sleeve, a spotlight coaxial with the photoelectric switch is fixedly plugged into the side wall of the end plate, the fan blades are arranged between the photoelectric switch and the spotlight, and the light emitted by the spotlight is projected to the photosensitive end of the photoelectric switch through the blade gap of the fan blade, the photoelectric switch and the spotlight are both electrically connected to the control main board, the control main board is provided with a counting module, and the counting module counts according to the electrical signal output by the photoelectric switch.

[0015] Preferably, a gas concentration detection probe is installed on the side wall of the reflux hood, and a detection end of the gas concentration detection probe is arranged inside the reflux hood. The gas concentration detection probe is used to detect the concentration of the protective gas, and the gas concentration detection probe is electrically connected to the control mainboard.

[0016] Preferably, a buzzer and a wireless signal transmitting module are installed on the side wall of the end plate, and the control main board controls the operation of the buzzer and the wireless signal transmitting module according to the electrical signal fed back by the gas concentration detection probe and the electrical signal fed back by the counting module.

[0017] Compared with the existing technology, a high voltage DC circuit breaker has the following advantages:

[0018] 1. Through the cooperation of the circuit breaker body, control main board and protection circuit unit, the load can be protected by emergency circuit. The hybrid switching method has low conduction loss and can cut off the fault current in a short time, which is not easy to generate arc. The redundant energy consumption unit can be based on the response speed of the protection circuit unit. When the response speed of the protection circuit unit is too slow, secondary switching can be performed and the current consumption can be reduced to ensure the safety of the current entering the load, improve the protection effect of the load, and ensure the stable operation of the power system.

[0019] 2. The heat dissipation unit can be used to dissipate heat and cool the circuit breaker body, so as to avoid the high temperature of the circuit breaker body affecting the response speed of the solid-state switch of the protection circuit unit, thereby reducing the opening and closing frequency of the redundant energy-consuming unit, which is conducive to maintaining the long-term stable operation of the entire circuit breaker body.

[0020] 3. Through the early warning mechanism set up, in cooperation with the resistance adjustment mechanism of the heat dissipation unit and the redundant energy consumption unit, the operation of the circuit breaker body can be automatically measured based on the temperature inside the circuit breaker body, and relevant personnel can be reminded to perform maintenance on the circuit breaker body in time. In conjunction with the secondary switching of the redundant energy consumption unit, the phenomenon of poor load protection effect caused by the untimely response speed of the solid-state switch can be further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a circuit diagram of a high-voltage DC circuit breaker provided by the present invention;

[0022] Figure 2 It is a structural schematic diagram of a high-voltage DC circuit breaker provided by the present invention;

[0023] Figure 3 It is a schematic diagram of a redundant energy consumption unit of a high-voltage DC circuit breaker provided by the present invention;

[0024] Figure 4 It is a schematic diagram of a top view of the structure of a high-voltage DC circuit breaker provided by the present invention;

[0025] Figure 5 It is a schematic diagram of the internal structure of a circular sleeve of a high-voltage DC circuit breaker provided by the present invention;

[0026] Figure 6 It is a schematic diagram of the side wall structure of an end plate of a high-voltage DC circuit breaker provided by the present invention;

[0027] Figure 7 The present invention is a schematic diagram of the internal structure of a magnetic isolation hollow plate of a high-voltage DC circuit breaker provided by the present invention.

[0028] In the figure: 1 circuit breaker body, 2 control main board, 3 protection circuit unit, 31 mechanical switch on-off circuit, 32 solid-state switch switching circuit, 33 energy consumption circuit, 4 external power supply end, 5 load, 6 redundant energy consumption unit, 61 double-throw switch, 62 battery assembly, 63 timing switch, 64 normally closed switch, 7 heat dissipation unit, 71 round sleeve, 72 end plate, 73 drive motor, 74 fan blade, 75 air intake pipe, 76 return cover, 77 external circulation heat dissipation pipe, 8 resistance adjustment mechanism, 81 magnetic isolation hollow plate, 82 left insulating column, 83 resistor rod, 84 right insulating column, 85 electromagnetic push rod, 86 insulating push block, 87 conductive slip ring, 9 early warning mechanism, 91 temperature detection probe, 92 photoelectric switch, 93 spotlight, 94 counting module, 10 gas concentration detection probe, 11 buzzer, 12 wireless signal transmission module. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] like Figure 1-Figure 7 As shown, a high-voltage DC circuit breaker includes a circuit breaker body 1. A control main board 2 and a protection circuit unit 3 are arranged inside the circuit breaker body 1. An external power supply terminal 4 supplies power to a load 5 through the protection circuit unit 3. The protection circuit unit 3 includes a mechanical switch on-off circuit 31, a solid-state switch switching circuit 32 and an energy consumption circuit 33. When the circuit works normally, the external power supply terminal 4 supplies power to the load 5 through the mechanical switch on-off circuit 31 and the solid-state switch switching circuit 32. When a circuit fails, the solid-state switch switching circuit 32 performs a switching action to disconnect the mechanical switch on-off circuit 31 and cooperate with the energy consumption circuit 33 to consume overload current.

[0031] The redundant energy consumption unit 6 is arranged between the output end of the circuit breaker body 1 and the input end of the load 5, the redundant energy consumption unit 6 is electrically connected to the output end of the protection circuit unit 3, the output end of the redundant energy consumption unit 6 is electrically connected to the input end of the load 5, the redundant energy consumption unit 6 includes a double-throw switch 61 and a battery assembly 62, the output end of the mechanical switch on-off circuit 31 is electrically connected to the input end of the double-throw switch 61, one of the output ends of the double-throw switch 61 is electrically connected to the input end of the load 5, the other output end of the double-throw switch 61 is electrically connected to the input end of the resistance adjustment mechanism 8, the output end of the resistance adjustment mechanism 8 is electrically connected to the input end of the load 5, the positive and negative ends of the battery assembly 62 are electrically connected to the input end of the resistance adjustment mechanism 8, and the positive and negative ends of the battery assembly 62 are electrically connected to the input end of the resistance adjustment mechanism 8. The ends are electrically connected with a timing switch 63 and a normally closed switch 64 respectively, and the timing switch 63 and the normally closed switch 64 are electrically connected to the power supply end of the double-throw switch 61, and the normally closed switch 64 is electrically connected to the solid-state switch switching circuit 32. When the timing switch 63 is closed, the timing switch 63 will disconnect the power supply circuit of the normally closed switch 64. When the normally closed switch 64 is disconnected, the normally closed switch 64 will disconnect the power supply circuit of the timing switch 63. When the control mainboard 2 controls the timing switch 63 to work, the timing switch 63 starts timing and can be closed immediately when the timing reaches the set value. Under normal working conditions, the battery assembly 62 is charged by the external power supply circuit.

[0032] The heat dissipation unit 7 is installed on the outer wall of the circuit breaker body 1, and the heat dissipation unit 7 is connected to the inside of the circuit breaker body 1. The inside of the heat dissipation unit 7 and the circuit breaker body 1 are filled with protective gas. The redundant energy consumption unit 6 is provided with a resistance adjustment mechanism 8. The heat dissipation unit 7 includes a circular sleeve 71 fixedly installed on the outer wall of the circuit breaker body 1, and a detachable end plate 72 is installed at the end of the circular sleeve 71. A drive motor 73 is installed on the side wall of the end plate 72, and the output end of the drive motor 73 is rotated with the side wall of the end plate 72. The circular sleeve 71 is connected, a fan blade 74 is arranged inside, and the output end of the driving motor 73 drives the fan blade 74 to rotate, a plurality of air inlet pipes 75 are fixedly plugged into the side wall of the circuit breaker body 1 located inside the circular sleeve 71, a return cover 76 is fixedly connected to the side wall of the circuit breaker body 1 away from the circular sleeve 71, and a group of external circulation heat dissipation pipes 77 are fixedly connected between the return cover 76 and the circular sleeve 71, the driving motor 73 is electrically connected to the control main board 2, and the external circulation heat dissipation pipe 77 adopts an aluminum alloy pipe with good heat dissipation.

[0033] The resistance regulating mechanism 8 comprises a magnetic isolation hollow plate 81 arranged on the side wall of the circuit breaker body 1, a left insulating column 82 is fixedly installed inside the magnetic isolation hollow plate 81, and a resistor rod 83 is fixedly installed at the end of the left insulating column 82, and the end of the resistor rod 83 away from the right insulating column 84 is installed with the right insulating column 84 together with the magnetic isolation hollow plate 81, an electromagnetic push rod 85 is fixedly installed inside the magnetic isolation hollow plate 81, and an insulating push block 86 is installed at the telescopic end of the electromagnetic push rod 85, a conductive slip ring 87 is fixedly inserted on the side wall of the insulating push block 86, and the conductive slip ring 87 is in sliding contact with the rod wall of the resistor rod 83, the control main board 2 controls the operation of the electromagnetic push rod 85 according to the strength of the fault signal input, and the output end of the double-throw switch 61 is electrically connected to the input end of the load 5 through the end of the resistor rod 83 close to the left insulating column 82 and the conductive slip ring 87.

[0034] The early warning mechanism 9 is arranged inside the heat dissipation unit 7, the early warning mechanism 9 is electrically connected to the resistance adjustment mechanism 8, the resistance adjustment mechanism 8 is electrically connected to the heat dissipation unit 7, the early warning mechanism 9 includes a temperature detection probe 91 that is detachably plugged into the end face of the circuit breaker body 1, and the detection end of the temperature detection probe 91 is arranged inside the circuit breaker body 1, the control main board 2 controls the electromagnetic push rod 85 to work according to the electrical signal output by the temperature detection probe 91, the end of the resistance rod 83 close to the right insulating column 84 is electrically connected to the drive motor 73 through the conductive slip ring 87 and the control main board 2, and the outer wall of the circuit breaker body 1 is located at the circular sleeve 7 A photoelectric switch 92 is installed at the inner position of the end plate 72, a spotlight 93 coaxial with the photoelectric switch 92 is fixedly inserted on the side wall of the end plate 72, the fan blade 74 is arranged between the photoelectric switch 92 and the spotlight 93, and the light emitted by the spotlight 93 is projected to the photosensitive end of the photoelectric switch 92 through the blade gap of the fan blade 74, the photoelectric switch 92 and the spotlight 93 are both electrically connected to the control main board 2, the control main board 2 is provided with a counting module 94, and the counting module 94 counts according to the electrical signal output by the photoelectric switch 92, and the counting module 94 can receive the electrical signal output by the photoelectric switch 92 and count.

[0035] A gas concentration detection probe 10 is installed on the side wall of the reflux hood 76, and the detection end of the gas concentration detection probe 10 is arranged inside the reflux hood 76. The gas concentration detection probe 10 is used to detect the concentration of the protective gas, and the gas concentration detection probe 10 is electrically connected to the control main board 2. The gas concentration detection probe 10 can detect the concentration of the protective gas. When the protective gas leaks, the concentration of the protective gas decreases. At this time, the gas concentration detection probe 10 will feedback an electrical signal to the control main board 2 to remind personnel to replenish the protective gas and repair the leakage point of the protective gas in time.

[0036] A buzzer 11 and a wireless signal transmitting module 12 are installed on the side wall of the end plate 72. The control main board 2 controls the operation of the buzzer 11 and the wireless signal transmitting module 12 according to the electrical signal fed back by the gas concentration detection probe 10 and the electrical signal fed back by the counting module 94. When the control main board 2 receives the electrical signal fed back by the gas concentration detection probe 10 to control the buzzer 11 and receives the electrical signal fed back by the counting module 94 to control the buzzer 11, the beeping sound of the buzzer 11 is different, which is convenient for personnel to distinguish.

[0037] The operating principle of the present invention is now described as follows: the external power supply terminal 4 supplies power to the load 5 through the protection circuit unit 3 and the redundant energy consumption unit 6. Under normal working conditions, the current input by the external power supply terminal 4 supplies power to the load 5 through the mechanical switch on-off circuit 31, the solid-state switch switching circuit 32 and the double-throw switch 61. When a line fails, an external fault detection device, such as a current transformer, will feed back an electrical signal to the control mainboard 2. After receiving the fault signal, the control mainboard 2 will immediately control the solid-state switch of the solid-state switch switching circuit 32 to switch. After the solid-state switch switching circuit 32 is switched, the solid-state switch switching circuit 32 is switched. The current passing through the mechanical switch on-off circuit 31 gradually decreases, while the current passing through the solid-state switch switching circuit 32 gradually increases. When the current is completely transferred to the solid-state switch switching circuit 32, the mechanical switch on-off circuit 31 is disconnected. Subsequently, the solid-state switch of the solid-state switch switching circuit 32 is cut off, and the overload current is consumed by the energy consumption circuit 33. For example, the mechanical switch on-off circuit 31 mainly includes a first isolating switch, a first mechanical switch, a second mechanical switch, an auxiliary DC switch, a first diode and a second diode. The solid-state switch switching circuit 32 mainly includes a solid-state switch, a second isolating switch, a line impedance and a freewheeling diode. The energy consumption circuit 33 consumes the overload current. The circuit 33 mainly includes a third diode, a fourth diode, a third isolation switch, an energy absorption resistor, an MOV metal oxide varistor, a capacitor, etc. In normal operation, the current mainly flows in through the first magnetic isolation switch, the first mechanical switch, the second mechanical switch, the auxiliary DC switch and the solid-state switch, and flows to the load 5 through the first diode, the second diode, the line impedance and the freewheeling diode. After a fault occurs, the control motherboard 2 controls the solid-state switch to operate. Since the current of the line impedance cannot change suddenly, the line impedance current will flow through the freewheeling diode to maintain the continuity of the current. At the same time, the energy consumption circuit including the capacitor and the energy absorption resistor 33 starts to work, the inductor current will charge the capacitor through the third diode and the fourth diode, the voltage on the capacitor gradually increases, the current gradually increases, and at the same time the energy-absorbing resistor consumes the energy in the inductor, limiting the rate of increase of the capacitor voltage, thus protecting the circuit. As the capacitor voltage increases, the MOV starts to conduct. The MOV is a nonlinear resistor element that presents a high resistance state under normal voltage. When the voltage exceeds a certain value, its resistance decreases rapidly, thereby quickly absorbing the energy in the inductor, further limiting the overvoltage in the circuit, and protecting other components in the circuit, such as mechanical switches, solid-state switches, etc., from the impact of overvoltage;

[0038] When a line fails, the control mainboard 2 not only controls the solid-state switch of the solid-state switch switching circuit 32, but also sends instructions to the timing switch 63. When the solid-state switch of the solid-state switch switching circuit 32 responds in time, the solid-state switch will complete the shutdown action within 7 milliseconds. At this time, the solid-state switch will control the power supply circuit of the normally closed switch 64 to energize, so that the contacts of the normally closed switch 64 are disconnected, and the power supply circuit of the timing switch 63 is disconnected at the same time, so the timing switch 63 cannot continue to work. At this time, the normally closed switch 64, the timing switch 63 and the battery assembly 62 remain disconnected from the power supply circuit of the double-throw switch 61, that is, the double-throw switch 61 does not operate. Since the solid-state switch responds promptly enough, the current passing through the double-throw switch 61 has been reduced to a safe range when the line fails, and will not be caused. The load 5 is damaged. When the solid-state switch does not respond in time, that is, the solid-state switch does not complete the shutdown action within 7 milliseconds, the timing switch 63 will be closed immediately after the timing reaches 7 milliseconds. At this time, the timing switch 63 will not only close the normally closed switch 64, the battery assembly 62 and the double-throw switch 61 power supply circuit, but also disconnect the normally closed switch 64 power supply circuit. Therefore, even if the solid-state switch completes the shutdown action after 7 milliseconds, the normally closed switch 64 will not be powered on at this time, that is, the normally closed switch 64, the battery assembly 62, the timing switch 63 and the double-throw switch 61 power supply circuit remain in the conductive state. At this time, the double-throw switch 61 will switch, so that the current flowing into the double-throw switch 61 passes through the end of the resistor rod 83 close to the left insulating column 82 and the conductive slip ring 87 and flows into the load 5.

[0039] Among them, when the control mainboard 2 receives an external fault signal, it will control the electromagnetic push rod 85 to work according to the strength of the received fault signal. For example, when the fault current strength is too large, the current strength detected by the current transformer will also be too large. At this time, the strength of the electrical signal output to the control mainboard 2 is also too large. At this time, the control mainboard 2 controls the current passing into the electromagnetic push rod 85 to increase synchronously, and the displacement distance of the electromagnetic push rod 85 pushing the insulating push block 86 increases synchronously. Therefore, when the overload current is larger, the electromagnetic push rod 85 pushes the insulating push block 86 to drive the conductive slip ring 87 to move farther. At this time, the end of the resistor rod 83 close to the left insulating column 82 is connected to the conductive slip ring 87. The longer the length, the greater the resistance. Therefore, the resistance of the resistor rod 83 and the conductive slip ring 87 can be automatically adjusted according to the overload current strength to ensure that the resistance used for energy consumption is appropriate. When the current flows through the resistor rod 83, the current will be converted into heat consumption to avoid the phenomenon that the solid-state switch of the solid-state switch switching circuit 32 does not respond in time, resulting in overload current input to the load 5, causing damage to the load 5;

[0040] During normal operation of the circuit breaker body 1, more heat will be generated inside the circuit breaker body 1 due to the current passing through the inside of the circuit breaker body 1. As the heat accumulates, the temperature inside the circuit breaker body 1 rises. At this time, the temperature detection probe 91 will detect the temperature rise. When the temperature exceeds 50°C, the temperature detection probe 91 will feedback an electrical signal to the control main board 2. The control main board 2 will control the drive motor 73 to connect the connection circuit with the end of the resistor rod 83 close to the right insulating column 84 and the conductive slip ring 87. At this time, the drive motor 73 is powered on and the drive motor 73 can drive the fan blades 74 to rotate. Therefore, under the action of the rotating fan blades 74, the protective gas inside the circuit breaker body 1 will start to flow and flow into the reflow cover 76, and then flow back to the inside of the circular sleeve 71 through the external circulation heat dissipation pipe 77, so that the protective gas can pass through the circular sleeve 71, the inside of the circuit breaker body 1, the reflow cover 76 and the external circulation heat dissipation pipe 77. The heat pipe 77 circulates, and when the protective gas flows through the external circulation heat dissipation pipe 77, it can exchange heat with the external environment, so that the protective gas can be cooled. The cooled protective gas then exchanges heat with the circuit breaker body 1, so as to achieve heat dissipation and cooling of the circuit breaker body 1. Secondly, when the temperature detected by the temperature detection probe 91 is higher, the strength of the electrical signal fed back to the control main board 2 is higher. At this time, the control main board 2 controls the current passed into the electromagnetic push rod 85 to be greater, that is, the higher the temperature, the electromagnetic push rod 85 pushes the insulating push block 86 to drive the conductive slip ring 87 closer to the right insulating column 84, so that the length of the resistor rod 83 connected to the conductive slip ring 87 and the drive motor 73 in the connection loop becomes shorter, thereby making the connection loop resistance of the resistor rod 83, the conductive slip ring 87 and the drive motor 73 smaller, that is, the higher the temperature, the faster the speed at which the drive motor 73 drives the fan blade 74 to rotate to meet the heat dissipation requirements;

[0041] Among them, since high temperature will accelerate the aging of electronic components inside the solid-state switch, as the temperature rises, the electron migration phenomenon intensifies, the performance of the semiconductor material changes, resulting in the performance degradation of the solid-state switch, thereby affecting its response speed. Therefore, when the temperature is higher, the solid-state switch of the solid-state switch switching circuit 32 is more affected, and it is necessary to maintain the solid-state switch and other components in time. When the fan blade 74 is rotated to a certain angle, the blade of the fan blade 74 will move between the photoelectric switch 92 and the spotlight 93. At this time, the blade of the fan blade 74 will react to the light emitted by the spotlight 93. The light is blocked, and as the fan blades 74 rotate, when the gap between adjacent blades moves to between the photoelectric switch 92 and the spotlight 93, the light emitted by the spotlight 93 will irradiate the photoelectric switch 92, and the photoelectric switch 92 will convert the optical signal into an electrical signal and output it to the counting module 94 of the control main board 2. Each time the counting module 94 receives an electrical signal, it will increase the count. When the counting module 94 counts to a set value, the counting module 94 will feed back an electrical signal to the control main board 2, and the control main board 2 will immediately control the buzzer 11 and the wireless signal transmission module 11. When the block 12 works, the buzzer 11 can give an alarm reminder on site, and the wireless signal transmission module 12 will send a reminder message to the terminal device (such as a mobile phone) of the relevant personnel to remind the personnel to perform maintenance on the circuit breaker. As the temperature is higher, the rotation speed of the fan blade 74 is faster, the frequency of the light-transmitting gap between the photoelectric switch 92 and the spotlight 93 is higher, the frequency of the electrical signal fed back by the photoelectric switch 92 to the counting module 94 increases, and the counting speed of the counting module 94 increases synchronously, so the reminder interval time for the maintenance of the circuit breaker body 1 will be shortened to ensure that the circuit breaker is properly maintained. The timeliness of the maintenance reminder of the circuit breaker body 1 (wherein the photoelectric switch 92 and the spotlight 93 are located at the outer edge of the fan blade 74, where the gap width is relatively large, and even at a faster rotation speed, the light emitted by the spotlight 93 can be projected through the gap to the photoelectric switch 92). Since personnel can be reminded to perform maintenance on the circuit breaker body 1 in a timely manner, the possibility of untimely response of the solid-state switch switching circuit 32 can be reduced, thereby reducing the frequency of switching actions of the double-throw switch 61, and further improving the stability of the circuit breaker body 1 for emergency protection of the circuit.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-voltage direct current circuit breaker, comprising a circuit breaker body (1), wherein a control main board (2) and a protection circuit unit (3) are arranged inside the circuit breaker body (1), and an external power supply terminal (4) supplies power to a load (5) through the protection circuit unit (3), characterized in that: Also includes: A redundant energy consumption unit (6) is arranged between the output end of the circuit breaker body (1) and the input end of the load (5), the redundant energy consumption unit (6) is electrically connected to the output end of the protection circuit unit (3), and the output end of the redundant energy consumption unit (6) is electrically connected to the input end of the load (5); A heat dissipation unit (7) is mounted on the outer wall of the circuit breaker body (1), and the heat dissipation unit (7) is connected to the inside of the circuit breaker body (1), the inside of the heat dissipation unit (7) and the circuit breaker body (1) are both filled with protective gas, and a resistance adjustment mechanism (8) is arranged inside the redundant energy consumption unit (6); The early warning mechanism (9) is arranged inside the heat dissipation unit (7); the early warning mechanism (9) is electrically connected to the resistance adjustment mechanism (8); and the resistance adjustment mechanism (8) is electrically connected to the heat dissipation unit (7).

2. A high voltage DC circuit breaker according to claim 1, characterized in that: The protection circuit unit (3) comprises a mechanical switch on-off circuit (31), a solid-state switch switching circuit (32) and an energy consumption circuit (33). When the circuit is working normally, the external power supply end (4) supplies power to the load (5) through the mechanical switch on-off circuit (31) and the solid-state switch switching circuit (32). When a circuit fault occurs, the solid-state switch switching circuit (32) performs a switching action to disconnect the mechanical switch on-off circuit (31) and cooperates with the energy consumption circuit (33) to consume overload current.

3. A high voltage DC circuit breaker according to claim 2, characterized in that: The redundant energy consumption unit (6) comprises a double-throw switch (61) and a battery assembly (62); the output end of the mechanical switch on-off circuit (31) is electrically connected to the input end of the double-throw switch (61); one of the output ends of the double-throw switch (61) is electrically connected to the input end of the load (5); the other output end of the double-throw switch (61) is electrically connected to the input end of the resistance adjustment mechanism (8); the output end of the resistance adjustment mechanism (8) is electrically connected to the input end of the load (5); the positive terminal of the battery assembly (62) is electrically connected to the input end of the load (5); The negative ends are electrically connected to a timing switch (63) and a normally closed switch (64), respectively, and the timing switch (63) and the normally closed switch (64) are electrically connected to the power supply end of the double-throw switch (61), and the normally closed switch (64) is electrically connected to the solid-state switch switching circuit (32). When the timing switch (63) is closed, the timing switch (63) disconnects the power supply circuit of the normally closed switch (64), and when the normally closed switch (64) is disconnected, the normally closed switch (64) disconnects the power supply circuit of the timing switch (63).

4. A high voltage DC circuit breaker according to claim 3, characterized in that: The heat dissipation unit (7) comprises a circular sleeve (71) fixedly mounted on the outer wall of the circuit breaker body (1); a detachable end plate (72) is mounted on the end of the circular sleeve (71); a driving motor (73) is mounted on the side wall of the end plate (72); an output end of the driving motor (73) is rotatably connected to the side wall of the end plate (72); a fan blade (74) is arranged inside the circular sleeve (71); and the output end of the driving motor (73) drives the fan blade (74) to rotate; a plurality of air inlet pipes (75) are fixedly plugged into the side wall of the circuit breaker body (1) located inside the circular sleeve (71); a return hood (76) is fixedly connected to the side wall of the circuit breaker body (1) away from the circular sleeve (71); and a group of external circulation heat dissipation pipes (77) are fixedly connected between the return hood (76) and the circular sleeve (71); and the driving motor (73) is electrically connected to the control main board (2).

5. A high voltage DC circuit breaker according to claim 4, characterized in that: The resistance adjustment mechanism (8) comprises a magnetic isolation hollow plate (81) arranged on the side wall of the circuit breaker body (1), a left insulating column (82) is fixedly installed inside the magnetic isolation hollow plate (81), and a resistance rod (83) is fixedly installed at the end of the left insulating column (82), and the end of the resistance rod (83) away from the right insulating column (84) is installed with the right insulating column (84) together with the magnetic isolation hollow plate (81), and an electromagnetic push rod (85) is fixedly installed inside the magnetic isolation hollow plate (81), and the electromagnetic push rod (85) is fixedly installed inside the magnetic isolation hollow plate (81), and the electromagnetic push rod (85) is fixedly installed inside the magnetic isolation hollow plate (81), and the electromagnetic push rod (85) is fixedly installed inside the magnetic isolation hollow plate (81), and the electromagnetic push rod (85) is fixedly installed at the end of the left insulating column (82). An insulating push block (86) is installed at the telescopic end of the rod (85), and a conductive slip ring (87) is fixedly inserted into the side wall of the insulating push block (86), and the conductive slip ring (87) is in sliding contact with the rod wall of the resistor rod (83). The control main board (2) controls the electromagnetic push rod (85) to work according to the intensity of the fault signal input, and the output end of the double-throw switch (61) is electrically connected to the input end of the load (5) through one end of the resistor rod (83) close to the left insulating column (82) and the conductive slip ring (87).

6. A high voltage DC circuit breaker according to claim 5, characterized in that: The early warning mechanism (9) comprises a temperature detection probe (91) which is detachably plugged into the end surface of the circuit breaker body (1), and the detection end of the temperature detection probe (91) is arranged inside the circuit breaker body (1); the control main board (2) controls the electromagnetic push rod (85) to work according to the electrical signal output by the temperature detection probe (91); one end of the resistance rod (83) close to the right insulating column (84) is electrically connected to the drive motor (73) through a conductive slip ring (87) and the control main board (2); and a photoelectric switch is installed on the outer wall of the circuit breaker body (1) at a position inside the circular sleeve (71). The end plate (72) is provided with a spotlight (93) coaxial with the photoelectric switch (92), the fan blade (74) is arranged between the photoelectric switch (92) and the spotlight (93), and the light emitted by the spotlight (93) is projected to the photosensitive end of the photoelectric switch (92) through the blade gap of the fan blade (74), the photoelectric switch (92) and the spotlight (93) are both electrically connected to the control main board (2), and the control main board (2) is provided with a counting module (94), and the counting module (94) counts according to the electrical signal output by the photoelectric switch (92).

7. A high voltage DC circuit breaker according to claim 6, characterized in that: A gas concentration detection probe (10) is installed on the side wall of the reflux hood (76), and a detection end of the gas concentration detection probe (10) is arranged inside the reflux hood (76). The gas concentration detection probe (10) is used to detect the concentration of the protective gas, and the gas concentration detection probe (10) is electrically connected to the control mainboard (2).

8. A high voltage DC circuit breaker according to claim 7, characterized in that: A buzzer (11) and a wireless signal transmission module (12) are installed on the side wall of the end plate (72), and the control main board (2) controls the operation of the buzzer (11) and the wireless signal transmission module (12) according to the electrical signal fed back by the gas concentration detection probe (10) and the electrical signal fed back by the counting module (94).

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