Closing inrush current suppression device and method

Abstract

The embodiment of the invention discloses a closing inrush current suppression device and method. The closing inrush current suppression device comprises a circuit breaker; the closing resistor gap triggering module comprises an isolation transformer unit, a gap triggering mechanism and a gap triggering air chamber; the gap triggering air chambers are located on the two sides of the gap triggering mechanism. Each gap triggering air chamber comprises a closing resistor and a gap triggering contact unit. The closing resistor is connected with the gap triggering mechanism through the gap triggering contact unit, the closing resistor is connected with the circuit breaker, and the isolation transformer unit is connected with the gap triggering mechanism; the phase selection controller is connected with the circuit breaker and the isolation transformer unit and is used for receiving the control instruction and controlling the working states of the circuit breaker and the closing resistance gap triggering module according to the control instruction; when the switching-on inrush current suppression device is switched on, the circuit breaker firstly acts and then is switched on, and the switching-on resistor gap trigger module acts and then is switched on. According to the closing inrush current suppression device and method provided by the embodiment of the invention, the closing inrush current suppression reliability can be ensured.

Description

Technical Field

[0001] The embodiments of the present invention relate to a closing inrush current suppression technology, and more particularly to a closing inrush current suppression device and method. Background Art

[0002] In high-voltage direct current transmission projects, circuit breakers are used to filter out harmonics on the AC side and provide reactive power consumed by commutation. In actual operation, AC capacitors are frequently switched on and off as the transmission flow changes. When the circuit breaker is put into operation at different phase points, severe transient high-frequency closing surge currents and overvoltages will be generated, which can easily cause burning and welding of the circuit breaker contacts. At the same time, excessive surge currents and overvoltages may damage high-voltage equipment such as AC capacitors, resulting in a reduction in their electrical life. In addition, closing surge currents and overvoltages may also cause unbalanced protection of AC capacitors, which may cause harmonic instability in severe cases, causing bus voltage distortion and ultimately leading to commutation failure. Therefore, it is necessary to use a closing surge current suppression device to suppress the closing surge current.

[0003] At present, the existing closing inrush current suppression devices usually use series inductors and phase-selective closing methods to suppress the closing inrush current. The above-mentioned methods of suppressing the closing inrush current cannot change the mechanical dispersion of the circuit breaker. When the circuit breaker is frequently switched on and off, severe transient high-frequency closing inrush current and overvoltage will still be generated, affecting the reliability of the closing inrush current suppression. Summary of the invention

[0004] The embodiments of the present invention provide a closing inrush current suppression device and method to ensure the reliability of closing inrush current suppression.

[0005] In a first aspect, an embodiment of the present invention provides a closing inrush current suppression device, comprising:

[0006] breaker;

[0007] A closing resistor gap trigger module, comprising an isolation transformer unit, a gap trigger mechanism and a gap trigger air chamber; the gap trigger air chamber is located on both sides of the gap trigger mechanism, and the gap trigger air chamber comprises a closing resistor and a gap trigger contact unit; the closing resistor is connected to the gap trigger mechanism through the gap trigger contact unit, the closing resistor is connected to the circuit breaker, and the isolation transformer unit is connected to the gap trigger mechanism;

[0008] A phase selection controller is connected to the circuit breaker and the isolation transformer unit, and is used to receive control instructions and control the working states of the circuit breaker and the closing resistance gap trigger module according to the control instructions; when the closing inrush current suppression device is closed, the circuit breaker is actuated first and then turned on, and the closing resistance gap trigger module is actuated later and then turned on.

[0009] Optionally, the gap trigger mechanism includes a gap trigger circuit, a control unit, a trigger optical fiber, an input power line, an output power line and a high-voltage housing;

[0010] The gap trigger circuit is connected to the control unit via the trigger optical fiber, the input power line is connected to the gap trigger circuit and the control unit, and the gap trigger circuit is connected to the gap trigger contact unit via the output power line; the gap trigger circuit, the control unit, the trigger optical fiber, the input power line, and the output power line are all located inside the high-voltage housing;

[0011] The phase selection controller is connected to the control unit via the isolation transformer unit, and the phase selection controller is used to control the working state of the gap trigger circuit via the control unit to control the connection state of the gap trigger circuit and the closing resistor.

[0012] Optionally, the gap trigger contact unit includes an ion injection contact, an ion receiving contact, an ion injector, a contact support and an injector power line; the first end of the closing resistor is connected to the circuit breaker, the second end of the closing resistor is suspended, the ion receiving contact is located at the second end of the closing resistor, the ion injection contact is located at one end of the contact support, and is arranged opposite to the ion receiving contact and has a spacing distance; the contact support is a hollow tube; the ion injector is located on a side of the ion injection contact away from the ion receiving contact and is located inside the contact support; the ion injector is connected to the gap trigger mechanism through the injector power line.

[0013] Optionally, the gap trigger air chamber also includes a sleeve, a flange and a terminal board, the first end of the closing resistor is connected to the circuit breaker, the second end of the closing resistor is suspended, the first end of the closing resistor is fixed to one end of the sleeve, the gap trigger contact unit is located at the other end of the sleeve, the terminal board is located at the flange, and the terminal board is used to connect the connecting line between the gap trigger contact unit and the gap trigger mechanism.

[0014] Optionally, the isolation transformer unit includes a transformer and a composite bushing, the transformer is a gas-insulated transformer, and the transformer is located inside the composite bushing.

[0015] Optionally, the composite sleeve is a fiber optic composite sleeve, which includes an optical fiber, a fiberglass cylinder and an umbrella skirt, the transformer is located inside the fiberglass cylinder, the umbrella skirt is located outside the fiberglass cylinder, the optical fiber is located between the umbrella skirt and the fiberglass cylinder, the optical fiber is a spirally wound structure, and the phase selection controller is connected to the gap trigger mechanism through the optical fiber.

[0016] Optionally, the closing surge current suppression device further includes an insulating gas connecting pipeline, and the air chamber of the isolation transformer unit is connected to the gap triggering air chamber through the insulating gas connecting pipeline.

[0017] In a second aspect, an embodiment of the present invention provides a method for suppressing a closing inrush current, the method for suppressing a closing inrush current being executed by the phase selection controller according to the first aspect, and the method for suppressing a closing inrush current comprising:

[0018] Receive control instructions;

[0019] According to the control instruction, the working states of the circuit breaker and the closing resistance gap trigger module are controlled; the circuit breaker is actuated first and then turned on, and the closing resistance gap trigger module is actuated later and then turned on.

[0020] Optionally, controlling the working state of the circuit breaker and the closing resistance gap trigger module according to the control instruction includes:

[0021] When the control instruction is a closing control instruction, performing zero-crossing detection and determining the sending time of the circuit breaker closing instruction and the sending time of the trigger instruction of the closing resistance gap trigger module;

[0022] When the time for sending the closing instruction of the circuit breaker is reached, a closing instruction is sent to the circuit breaker, and when the time for sending the trigger instruction is reached, a trigger instruction is sent to the closing resistance gap trigger module; the sending time of the closing instruction is earlier than the sending time of the trigger instruction;

[0023] When the circuit breaker is turned on, determining the time for sending the disconnection instruction of the closing resistance gap trigger module; the time when the circuit breaker is turned on is later than the time when the closing resistance gap trigger module is turned on;

[0024] When the disconnection instruction sending time arrives, sending a disconnection instruction to the closing resistance gap trigger module;

[0025] When the control instruction is a circuit breaker opening control instruction, performing zero-crossing detection and determining the time for sending the circuit breaker opening instruction;

[0026] When the time for sending the circuit breaker opening instruction is reached, an opening instruction is sent to the circuit breaker.

[0027] Optionally, the circuit breaker closing command sending time H3 = T + H5 - T 余 , the trigger instruction sending time of the closing resistance gap trigger module is H4=H3+H1-H5-1 / 2T-H2, where H1 is the closing time of the circuit breaker, H2 is the closing time of the closing resistance gap trigger module, H5 is the target closing time, T is the voltage waveform period, T余 =H1-nT, n is a positive integer, H1, H2, H5, T and n are all known numbers; the disconnection instruction sending time of the closing resistance gap trigger module is H6, H6>2ms.

[0028] The embodiments of the present invention provide a closing surge current suppression device and method, wherein the closing surge current suppression device comprises: a circuit breaker; a closing resistor gap trigger module, comprising an isolation transformer unit, a gap trigger mechanism and a gap trigger air chamber; the gap trigger air chamber is located on both sides of the gap trigger mechanism, and the gap trigger air chamber comprises a closing resistor and a gap trigger contact unit; the closing resistor is connected to the gap trigger mechanism through the gap trigger contact unit, the closing resistor is connected to the circuit breaker, and the isolation transformer unit is connected to the gap trigger mechanism; a phase selection controller is connected to the circuit breaker and the isolation transformer unit, and is used to receive control instructions, and control the working states of the circuit breaker and the closing resistor gap trigger module according to the control instructions; when the closing surge current suppression device is closed, the circuit breaker is actuated first and then turned on, and the closing resistor gap trigger module is actuated later and then turned on. The closing inrush current suppression device and method provided in the embodiment of the present invention realizes the rapid closing of the closing resistor gap trigger module to suppress the closing inrush current, and the dual redundant design of the circuit breaker to suppress the closing inrush current under the closing resistor gap trigger module failure condition through the control of the closing resistor gap trigger module and the circuit breaker by the phase selection controller, thereby ensuring the reliability of the closing inrush current suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of a closing inrush current suppression device provided by an embodiment of the present invention;

[0030] Figure 2 It is a structural schematic diagram of a closing resistance gap trigger module provided by an embodiment of the present invention;

[0031] Figure 3 is a structural schematic diagram of a gap trigger mechanism provided by an embodiment of the present invention;

[0032] Figure 4 is a schematic structural diagram of a gap-triggered air chamber provided by an embodiment of the present invention;

[0033] Figure 5 is a structural schematic diagram of a gap trigger contact unit provided by an embodiment of the present invention;

[0034] Figure 6 is a structural schematic diagram of an isolation transformer unit provided by an embodiment of the present invention;

[0035] Figure 7 It is a structural schematic diagram of an insulating gas communication pipeline provided by an embodiment of the present invention;

[0036] Figure 8It is a flow chart of a closing inrush current suppression method provided by an embodiment of the present invention;

[0037] Fig. 9 is a flow chart of another method for suppressing a closing inrush current provided by an embodiment of the present invention;

[0038] Fig.10 is a schematic diagram of a waveform and time provided by an embodiment of the present invention;

[0039] Fig.11 It is a schematic diagram of suppressing closing inrush current provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0041] Figure 1 Schematic diagram of a closing surge current suppression device provided by an embodiment of the present invention. Figure 1 The closing inrush current suppression device includes: a circuit breaker 10, a closing resistor gap trigger module 20 and a phase selection controller 30. The closing resistor gap trigger module 20 includes an isolation transformer unit 21, a gap trigger mechanism 22 and a gap trigger air chamber 23; the gap trigger air chamber 23 is located on both sides of the gap trigger mechanism 22, and the gap trigger air chamber 23 includes a closing resistor 24 and a gap trigger contact unit 25; the closing resistor 24 is connected to the gap trigger mechanism 22 through the gap trigger contact unit 25, the closing resistor 24 is connected to the circuit breaker 10, and the isolation transformer unit 21 is connected to the gap trigger mechanism 22; the phase selection controller 30 is connected to the circuit breaker 10 and the isolation transformer unit 21, and is used to receive control instructions, and control the working state of the circuit breaker 10 and the closing resistor gap trigger module 20 according to the control instructions; when the closing inrush current suppression device is closed, the circuit breaker is actuated first and then turned on, and the closing resistor gap trigger module is actuated later and then turned on.

[0042] Specifically, the closing inrush current suppression device can be applied to an AC system, such as being connected in series with an AC capacitor in the AC system to suppress the closing inrush current of the AC capacitor. Figure 1As shown, the closing resistor gap trigger module 20 is a T-type double-break gas insulation structure, and the closing resistor 24 and the gap trigger contact unit 25 are connected in series. The gap trigger air chamber 23 is a multi-break structure, and there are two gap trigger air chambers 23. The two gap trigger air chambers 23 are respectively located on both sides of the gap trigger mechanism 22, and one end of the closing resistor 24 in one gap trigger air chamber 23 is connected to one end of the circuit breaker 10, and one end of the closing resistor 24 in the other gap trigger air chamber 23 is connected to the other end of the circuit breaker 10, that is, the circuit breaker 10 and the closing resistor gap trigger module 20 are in parallel structure. In addition, the two ends of the circuit breaker 10 are located in the branch where the AC capacitor is located, that is, the circuit breaker 10 is connected in series with the AC capacitor. When the phase selection controller 30 receives a control instruction such as a closing control instruction, it controls the circuit breaker 10 to close, and controls the gap trigger mechanism 22 to work through the isolation transformer unit 21. The gap trigger mechanism 22 works to make the gap trigger contact unit 25 work, so that the closing resistor 24 is connected to the gap trigger mechanism 22 through the gap trigger contact unit 25, so that the closing resistor gap trigger module 20 is turned on. After the closing resistor gap trigger module 20 is turned on, the circuit breaker 10 is turned on. By controlling the closing resistor gap trigger module 20, the closing resistor gap trigger module 20 is quickly closed to suppress the closing surge current, and the dual redundant design of the circuit breaker suppressing the closing surge current under the fault condition of the closing resistor gap trigger module 20 is realized to ensure the reliability of closing surge current suppression.

[0043] It should be noted that the number of gap triggering air chambers in this embodiment is only for illustrative purposes and can be determined based on actual control requirements and is not limited here.

[0044] The closing surge suppression device provided in this embodiment includes: a circuit breaker; a closing resistor gap trigger module, including an isolation transformer unit, a gap trigger mechanism and a gap trigger air chamber; the gap trigger air chamber is located on both sides of the gap trigger mechanism, and the gap trigger air chamber includes a closing resistor and a gap trigger contact unit; the closing resistor is connected to the gap trigger mechanism through the gap trigger contact unit, the closing resistor is connected to the circuit breaker, and the isolation transformer unit is connected to the gap trigger mechanism; a phase selection controller is connected to the circuit breaker and the isolation transformer unit, and is used to receive control instructions, and control the working state of the circuit breaker and the closing resistor gap trigger module according to the control instructions; when the closing surge suppression device is closed, the circuit breaker is actuated first and then turned on, and the closing resistor gap trigger module is actuated later and turned on first. The closing surge suppression device provided in this embodiment realizes the fast closing of the closing resistor gap trigger module to suppress the closing surge through the control of the closing resistor gap trigger module and the circuit breaker by the phase selection controller, and the dual redundant design of the circuit breaker to suppress the closing surge under the fault condition of the closing resistor gap trigger module, so as to ensure the reliability of closing surge suppression.

[0045] Figure 2is a structural schematic diagram of a closing resistance gap trigger module provided by an embodiment of the present invention, Figure 3 Schematic diagram of a gap trigger mechanism provided by an embodiment of the present invention. Figure 2 and Figure 3 Optionally, the gap trigger mechanism 22 includes a gap trigger circuit 221, a control unit 222, a trigger optical fiber 223, an input power line 224, an output power line 225 and a high-voltage housing 226; the gap trigger circuit 221 is connected to the control unit 222 through the trigger optical fiber 223, the input power line 224 is connected to the gap trigger circuit 221 and the control unit 222, and the gap trigger circuit 221 is connected to the gap trigger contact unit 25 through the output power line 225; the gap trigger circuit 221, the control unit 222, the trigger optical fiber 223, the input power line 224 and the output power line 225 are all located inside the high-voltage housing 226; the phase selection controller 30 is connected to the control unit 222 through the isolation transformer unit 21, and the phase selection controller 30 is used to control the working state of the gap trigger circuit 221 through the control unit 222 to control the connection state of the gap trigger circuit 221 and the closing resistor 24.

[0046] Specifically, the input power line 224 provides working power for the gap trigger circuit 221 and the control unit 222, and the control unit 222 controls the working state of the gap trigger circuit 221 through the trigger optical fiber 223. The gap trigger circuit 221 is provided with components such as a switch tube, a diode and a capacitor, and the control unit 222 is connected to the control end of the switch tube in the gap trigger circuit 221 through the trigger optical fiber 223. The phase selection controller 30 sends a trigger instruction to the control unit 222 through the isolation transformer unit 21, and the control unit 222 transmits a control signal to the switch tube in the gap trigger circuit 221 through the trigger optical fiber 223 to control the on and off of the switch tube. For example, when the control unit 222 receives the trigger instruction, it transmits a high-level control signal to the switch tube, the switch tube is turned on, the gap trigger circuit 221 works, and the gap trigger circuit 221 is connected to the closing resistor 24.

[0047] Figure 4 is a schematic structural diagram of a gap-triggered air chamber provided by an embodiment of the present invention. Figure 5 Schematic diagram of the structure of a gap trigger contact unit provided by an embodiment of the present invention. Figure 4 and Figure 5Optionally, the gap trigger contact unit 25 includes an ion injection contact 251, an ion receiving contact 252, an ion injector 253, a contact support 254 and an injector power line 255. The first end of the closing resistor 24 is connected to the circuit breaker 10, and the second end of the closing resistor 24 is suspended. The ion receiving contact 252 is located at the second end of the closing resistor 24. The ion injection contact 251 is located at one end of the contact support 254, and is arranged opposite to the ion receiving contact 252 and has a spacing distance. The contact support 254 is a hollow tube. The ion injector 253 is located on the side of the ion injection contact 251 away from the ion receiving contact 252, and is located inside the contact support 254. The ion injector 253 is connected to the gap trigger mechanism 22 through the injector power line 255.

[0048] Specifically, the gap trigger contact unit 25 is a static structure. When the gap trigger mechanism 22 is working, the gap trigger mechanism 22 transmits current to the ion injector 253 through the injector power line 255. The ion injector 253 injects ions through the ion injection contact 251. When the ion receiving contact 252 receives ions, the closing resistor 24 is connected to the gap trigger circuit 221 through the gap trigger contact unit 25, and the closing resistor 24 is connected to the branch where the circuit breaker 10 is located.

[0049] refer to Figure 4 and Figure 5 Optionally, the gap trigger air chamber also includes a sleeve 26, a flange 27 and a terminal board 28, the first end of the closing resistor 24 is connected to the circuit breaker 10, the second end of the closing resistor 24 is suspended, the first end of the closing resistor 24 is fixed to one end of the sleeve 26, the gap trigger contact unit 25 is located at the other end of the sleeve 26, the terminal board 28 is located at the flange 27, and the terminal board 28 is used to connect the connecting line between the gap trigger contact unit 25 and the gap trigger mechanism 22.

[0050] The contact support 254 is fixed to the inner side of the flange 27 , that is, the side of the flange 27 close to the sleeve 26 , and the injector power line 255 is connected to the ion injector 253 along the inner space of the contact support 254 through the terminal board 28 .

[0051] Figure 6 Schematic diagram of the structure of an isolation transformer unit provided by an embodiment of the present invention. Figure 6 Optionally, the isolation transformer unit 21 includes a transformer 211 and a composite bushing 212 , the transformer 211 is a gas-insulated transformer, and the transformer 211 is located inside the composite bushing 212 .

[0052] The lead wires of the transformer 211 pass through the composite bushing 212, so that the lead wires are insulated from each other and from the outer shell of the transformer, and at the same time, the lead wires are fixed to achieve high and low voltage side insulation, data transmission and voltage transmission such as 220V / 220V voltage transmission. The composite bushing 212 includes various forms such as pure porcelain bushing, oil-filled bushing and capacitor bushing, which can be determined according to the actual device requirements and are not limited here.

[0053] refer to Figure 6 Optionally, the composite sleeve 212 is a fiber composite sleeve, the composite sleeve 212 includes an optical fiber 213, a fiberglass tube 214 and an umbrella skirt 215, the transformer 211 is located inside the fiberglass tube 214, the umbrella skirt 215 is located outside the fiberglass tube 214, the optical fiber 213 is located between the umbrella skirt 215 and the fiberglass tube 214, the optical fiber 213 is a spirally wound structure, and the phase selection controller 30 is connected to the gap trigger mechanism through the optical fiber 213.

[0054] Specifically, the glass fiber reinforced plastic cylinder 214 provides protection for the transformer and prevents the transformer from being affected by external weather. The shed 215 is an important insulating device, which is the outer insulating part of the composite bushing 212 and mainly functions to protect the transformer from weather influence and electrical corrosion. In addition, terminal plates 216, 217 and flanges 218 are provided at both ends of the glass fiber reinforced plastic cylinder 214.

[0055] Figure 7 Schematic diagram of the structure of an insulating gas connecting pipeline provided by an embodiment of the present invention. Figure 3 and Figure 7 Optionally, the closing surge current suppression device also includes an insulating gas connecting pipeline 40, and the air chamber of the isolation transformer unit 21 is connected to the gap triggering air chamber 23 through the insulating gas connecting pipeline 40.

[0056] Among them, the gap triggering air chamber 23 is a closed air chamber structure, and the insulating gas connecting pipeline 40 connects the air chamber of the isolation transformer unit 21 with the gap triggering air chamber 23 to achieve gas insulation. In addition, the insulating gas connecting pipeline 40 includes connecting flanges 41, 42 and a pipeline 43, and the connecting flanges 41, 42 are respectively located at both ends of the pipeline 43, and are respectively used to connect the flange of the gap triggering air chamber 23 and the flange of the isolation transformer unit 21.

[0057] Optionally, the closing inrush current suppression device is located in the branch where the target filter is located.

[0058] Specifically, the target filter may be an AC capacitor, and the closing inrush current suppression device is connected in series with the target filter. The closing inrush current generated by the target filter branch can be suppressed by the action of various components of the closing inrush current suppression device.

[0059] The closing inrush current suppression device provided in this embodiment combines the closing resistor with the closing resistor gap trigger module, realizing the electrical triggering of the closing resistor into the filter circuit; combining the closing resistor gap trigger module with the circuit breaker, utilizing the sub-microsecond fast closing capability of the closing resistor gap trigger module and the long-term closing and breaking capability of the circuit breaker, realizing the fast and accurate phase-fixed closing of the closing phase selection; the closing resistor gap trigger module is triggered during the closing process, reducing the contact ablation and the closing resistor current bearing capacity caused by the long-term current flow of the closing resistor gap trigger module. In addition, the closing resistor gap trigger module does not require the contact to move, and relies on the ion flow to conduct the circuit. The closing time of the closing resistor gap trigger module is sub-millisecond level less than 1ms, which is easy to meet the requirements of the mechanical dispersion of the closing time of ±0.5ms, and the closing time is still relatively stable after long-term triggering. Therefore, it is easy to set the best target closing point when matched with the phase selection controller, and it is an excellent phase selection closing switch.

[0060] Furthermore, the circuit breaker has the capabilities of long-term current flow and breaking, and the closing resistor gap trigger device has the ability to quickly close, combining the advantages of the two switches to achieve fast and accurate suppression of the closing inrush current of the filter; the closing resistor gap trigger module cooperates with the phase selection controller to achieve accurate closing at the voltage zero point, effectively avoiding the large closing inrush current value and the phase change failure caused by voltage distortion, avoiding the defects of unstable closing time and unstable pre-breakdown time of conventional circuit breakers, and avoiding the most direct problems of inability to effectively limit closing inrush current and phase change failure caused by the large dispersion of closing time and pre-breakdown time of conventional circuit breakers (about 0 to 8ms); the closing resistor gap trigger module is turned on before the circuit breaker When the circuit breaker is closed, both sides of the circuit breaker are at the same potential, and there is no pre-breakdown stage, which avoids contact ablation during pre-breakdown of conventional circuit breakers and improves the life of the closing inrush current suppression device; in the traditional solution, the closing resistor is installed on the circuit breaker, and the on and off of the closing resistor is controlled by a mechanical break. The time stability of the closing resistor being put into the line is poor, the dispersion is large, the mechanical vibration is large, and the defects of the closing resistor are easily exposed during long-term operation, resulting in damage to the closing resistor; in this embodiment, the closing resistor is combined with the closing resistor gap trigger module, and the on and off of the closing resistor in the line is controlled by the gap trigger module. The on and off time is stable, the dispersion is small, there is no mechanical vibration, the closing resistor is not affected by vibration, and the reliability and life can be improved.

[0061] Figure 8 : is a flow chart of a closing inrush current suppression method provided by an embodiment of the present invention. The closing inrush current suppression method is executed by the phase selection controller described in any embodiment of the present invention. The closing inrush current suppression method includes:

[0062] Step 110: Receive control instructions.

[0063] The control instruction may be sent to the phase selection controller by a host computer or a server that communicates with the phase selection controller, and the control instruction may be a closing control instruction or an opening control instruction.

[0064] Step 120: According to the control instruction, the working states of the circuit breaker and the closing resistance gap trigger module are controlled; the circuit breaker is actuated first and then turned on, and the closing resistance gap trigger module is actuated later and then turned on.

[0065] Specifically, when the control instruction is a closing control instruction, a zero-point detection is performed and the time for sending the closing instruction of the circuit breaker and the time for sending the trigger instruction of the closing resistor gap trigger module are determined; when the time for sending the closing instruction of the circuit breaker is reached, a closing instruction is sent to the circuit breaker, and when the time for sending the trigger instruction arrives, a trigger instruction is sent to the closing resistor gap trigger module; the sending time of the closing instruction is earlier than the sending time of the trigger instruction; when the circuit breaker is turned on, the time for sending the disconnection instruction of the closing resistor gap trigger module is determined; the time when the circuit breaker is turned on is later than the time when the closing resistor gap trigger module is turned on; when the time for sending the disconnection instruction arrives, a disconnection instruction is sent to the closing resistor gap trigger module; when the control instruction is an opening control instruction, a zero-point detection is performed and the time for sending the opening instruction of the circuit breaker is determined; when the time for sending the opening instruction of the circuit breaker is reached, an opening instruction is sent to the circuit breaker.

[0066] Fig. 9 is a flow chart of another method for suppressing inrush current when closing the switch provided by an embodiment of the present invention. Fig.10 Schematic diagram of a waveform and time provided by an embodiment of the present invention. Fig. 9 and Fig.10 , through multiple timers (the timers can be timers inside the phase selection controller), each instruction corresponds to each timer one by one. When the counter ends, the instruction corresponding to the timer is sent. The phase selection controller controls the circuit breaker to act first and then turn on, and the closing resistance gap trigger module acts later and turns on first, so as to realize the fixed-phase switching of the closing inrush current suppression device. Specifically, at any time ①, if the phase selection controller receives a closing instruction, it will carry out two stages: instruction confirmation and zero-crossing confirmation. At the end of the instruction confirmation time ②, the zero-crossing confirmation begins. In the zero-crossing confirmation stage, three zero-crossing points are confirmed continuously as the final reference voltage zero-crossing point. At the end of the zero-crossing confirmation time ③, the phase selection controller determines the circuit breaker closing instruction sending time H3=T+H5-T according to the system voltage waveform (the system voltage waveform can be input from the outside before receiving the instruction, and the system voltage waveform can be the voltage waveform of the system where the target filter connected to the closing inrush current device is located) and the circuit breaker closing time H1 (known and can be obtained in advance). 余 , and start the first timer, where T 余 =H1-nT,T 余is the remainder of the circuit breaker closing time divided by the waveform period, T is the waveform period, n is a positive integer, H5 is the target closing time (known), when H5 is between 0.5ms-1.5ms, it can ensure that the circuit breaker is closed at the optimal target closing point (the voltage waveform zero crossing point is delayed by 1ms), and at the same time, in order to ensure that the closing resistance gap trigger module is turned on at the voltage zero crossing point of 1 / 2 cycle before the circuit breaker is closed, the trigger instruction sending time of the closing resistance gap trigger module is determined to be H4=H3+H1-H5-1 / 2T-H2, and the second timer is started, H2 is the closing time of the closing resistance gap trigger module (known). According to the rule that the pre-breakdown time of the circuit breaker is less than 1 / 2 of the voltage cycle time, it can be judged that the conduction time of the closing resistance gap trigger module is earlier than the pre-breakdown time of the circuit breaker, which can ensure that the closing resistance gap trigger module is turned on earlier than the circuit breaker. Further, at the end time of the first timer ④, the phase selection controller sends a closing instruction to the circuit breaker to determine that the state of the closing resistor gap trigger module is normal. At the end time of the second timer ⑤, the phase selection controller sends a trigger instruction to the closing resistor gap trigger module to determine that the closing resistor gap trigger module and the circuit breaker are turned on. The disconnection instruction sending time H6 of the closing resistor gap trigger module is greater than 2ms, and the third timer is started. At the end time of the third timer ⑥, the phase selection controller sends a disconnection instruction to the closing resistor gap trigger module. When the phase selection controller receives the opening instruction, after the instruction confirmation and zero-crossing detection stages, the circuit breaker opening instruction sending time H7 is determined, and the fourth timer is started. At the end time of the fourth timer ⑦, the phase selection controller sends an opening instruction to the circuit breaker. After the above process, the closing inrush current suppression device completes a closing and opening working cycle. When determining the state of the closing resistor gap trigger module, if the state of the closing resistor gap trigger module is abnormal, the circuit breaker opening stage is directly entered, and the closing resistor gap trigger module is no longer operated. Therefore, the closing inrush current suppression device can realize the dual redundant design of fast closing of the closing resistor gap trigger module to suppress the closing inrush current under normal working condition and the closing inrush current suppression of the circuit breaker under the closing resistor gap trigger module failure condition.

[0067] Furthermore, the operation process of the closing inrush current suppression device is as follows: when the phase selection controller receives the closing instruction, it controls the circuit breaker to start closing according to the system voltage phase angle and the specific timing. At this time, the closing inrush current suppression device can be switched on and off at the optimal target closing point with a fixed phase, and then the action moment of the closing resistor gap trigger module is controlled to be the moment corresponding to the voltage zero-crossing phase of the 1 / 2 phase before the end of the circuit breaker closing time. The closing resistor gap trigger module is triggered to be turned on before the pre-breakdown of the circuit breaker. The turn-on time of the closing resistor gap trigger module is less than 1ms. The short closing time performance of the closing resistor gap trigger turn-on makes the closing resistor turn on quickly, and the closing inrush current is limited to the minimum, until the circuit breaker is closed at the optimal target point to achieve long-term energized current flow, and the phase selection controller controls the closing resistor gap trigger module to disconnect and exit operation. When the circuit breaker is opened, the phase selection controller controls the circuit breaker action, and the circuit breaker bears the breaking current and the recovery voltage. The closing resistance gap trigger module is controlled to be disconnected by the phase selection controller before the circuit breaker is opened. Therefore, the closing resistance gap trigger module does not participate in the opening when the circuit breaker is opened.

[0068] In addition, the fast closing capability of the closing resistor gap trigger module in the closing inrush current suppression device improves the accuracy of the closing time of the phase selector control switch, avoiding excessive closing inrush current, voltage distortion and commutation failure in the pre-breakdown phase of the circuit breaker alone. Since the closing resistor gap trigger module can be turned on within 1ms (about 600μs), the turn-on time is the pre-breakdown moment. For example, Fig.11 Schematic diagram of a method for suppressing a closing surge current provided by an embodiment of the present invention. Fig.11 , 3σ 间隙开关 μs level, 3σ 间隙开关 It is determined by the dispersion of the inherent closing time of the closing resistor gap trigger module. Since the closing resistor gap trigger module is triggered by an electronic circuit, 3σ 间隙开关 It is tens of μs. Even after frequent triggering, the triggering time and dispersion remain almost unchanged. Compared with the circuit breaker 3σ of ±1ms, the closing resistance gap trigger module can be effectively controlled to be turned on near the voltage zero point. Since the conduction time dispersion of the closing resistance gap trigger device is small, the system voltage is small when the closing resistance gap trigger module is turned on. Combined with the effect of the closing resistor in the device, the closing inrush current can be well suppressed.

[0069] It should be noted that the size of each parameter in this embodiment can be determined according to actual control requirements and is not limited here.

[0070] The closing inrush current suppression method provided in this embodiment belongs to the same inventive concept as the closing inrush current suppression device provided in any embodiment of the present invention, and has corresponding beneficial effects. For technical details not detailed in this embodiment, please refer to the closing inrush current suppression device provided in any embodiment of the present invention.

[0071] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A closing surge current suppression device, characterized in that: include: breaker; A closing resistor gap trigger module, comprising an isolation transformer unit, a gap trigger mechanism and a gap trigger air chamber; the gap trigger air chamber is located on both sides of the gap trigger mechanism, and the gap trigger air chamber comprises a closing resistor and a gap trigger contact unit; the closing resistor is connected to the gap trigger mechanism through the gap trigger contact unit, the closing resistor is connected to the circuit breaker, and the isolation transformer unit is connected to the gap trigger mechanism; A phase selection controller is connected to the circuit breaker and the isolation transformer unit, and is used to receive control instructions and control the working states of the circuit breaker and the closing resistance gap trigger module according to the control instructions; when the closing inrush current suppression device is closed, the circuit breaker is actuated first and then turned on, and the closing resistance gap trigger module is actuated later and then turned on.

2. The closing inrush current suppression device according to claim 1, characterized in that: The gap trigger mechanism includes a gap trigger circuit, a control unit, a trigger optical fiber, an input power line, an output power line and a high-voltage housing; The gap trigger circuit is connected to the control unit via the trigger optical fiber, the input power line is connected to the gap trigger circuit and the control unit, and the gap trigger circuit is connected to the gap trigger contact unit via the output power line; the gap trigger circuit, the control unit, the trigger optical fiber, the input power line, and the output power line are all located inside the high-voltage housing; The phase selection controller is connected to the control unit via the isolation transformer unit, and the phase selection controller is used to control the working state of the gap trigger circuit via the control unit to control the connection state of the gap trigger circuit and the closing resistor.

3. The closing inrush current suppression device according to claim 1, characterized in that: The gap trigger contact unit includes an ion injection contact, an ion receiving contact, an ion injector, a contact support and an injector power line. The first end of the closing resistor is connected to the circuit breaker, and the second end of the closing resistor is suspended. The ion receiving contact is located at the second end of the closing resistor. The ion injection contact is located at one end of the contact support and is arranged opposite to the ion receiving contact with a spacing distance. The contact support is a hollow tube. The ion injector is located on a side of the ion injection contact away from the ion receiving contact and is located inside the contact support. The ion injector is connected to the gap trigger mechanism through the injector power line.

4. The closing inrush current suppression device according to claim 1, characterized in that: The gap trigger air chamber also includes a sleeve, a flange and a terminal board. The first end of the closing resistor is connected to the circuit breaker, and the second end of the closing resistor is suspended. The first end of the closing resistor is fixed to one end of the sleeve, and the gap trigger contact unit is located at the other end of the sleeve. The terminal board is located at the flange, and the terminal board is used to connect the connecting line between the gap trigger contact unit and the gap trigger mechanism.

5. The closing inrush current suppression device according to claim 1, characterized in that: The isolation transformer unit comprises a transformer and a composite bushing, wherein the transformer is a gas-insulated transformer and is located inside the composite bushing.

6. The closing inrush current suppression device according to claim 5, characterized in that: The composite sleeve is a fiber composite sleeve, which includes an optical fiber, a fiberglass tube and an umbrella skirt. The transformer is located inside the fiberglass tube, the umbrella skirt is located outside the fiberglass tube, the optical fiber is located between the umbrella skirt and the fiberglass tube, the optical fiber is a spirally wound structure, and the phase selection controller is connected to the gap trigger mechanism through the optical fiber.

7. The closing inrush current suppression device according to claim 1, characterized in that: It also includes an insulating gas communicating pipeline, through which the air chamber of the isolation transformer unit is communicated with the gap triggering air chamber.

8. A method for suppressing inrush current during closing, characterized in that: The closing inrush current suppression method is executed by the phase selection controller according to any one of claims 1 to 7, and the closing inrush current suppression method includes: Receive control instructions; According to the control instruction, the working states of the circuit breaker and the closing resistance gap trigger module are controlled; the circuit breaker is actuated first and then turned on, and the closing resistance gap trigger module is actuated later and then turned on.

9. The method for suppressing closing inrush current according to claim 8, characterized in that: According to the control instruction, controlling the working state of the circuit breaker and the closing resistance gap trigger module includes: When the control instruction is a closing control instruction, performing zero-crossing detection and determining the sending time of the circuit breaker closing instruction and the sending time of the trigger instruction of the closing resistance gap trigger module; When the time for sending the closing instruction of the circuit breaker is reached, a closing instruction is sent to the circuit breaker, and when the time for sending the trigger instruction is reached, a trigger instruction is sent to the closing resistance gap trigger module; the sending time of the closing instruction is earlier than the sending time of the trigger instruction; When the circuit breaker is turned on, determining the time for sending the disconnection instruction of the closing resistance gap trigger module; the time when the circuit breaker is turned on is later than the time when the closing resistance gap trigger module is turned on; When the disconnection instruction sending time arrives, sending a disconnection instruction to the closing resistance gap trigger module; When the control instruction is a circuit breaker opening control instruction, performing zero-crossing detection and determining the time for sending the circuit breaker opening instruction; When the time for sending the circuit breaker opening instruction is reached, an opening instruction is sent to the circuit breaker.

10. The method for suppressing the closing inrush current according to claim 9, characterized in that: The circuit breaker closing command sending time H3 = T + H5 - T 余 , the trigger instruction sending time of the closing resistance gap trigger module is H4=H3+H1-H5-1 / 2T-H2, where H1 is the closing time of the circuit breaker, H2 is the closing time of the closing resistance gap trigger module, H5 is the target closing time, T is the voltage waveform period, T 余 =H1-nT, n is a positive integer, H1, H2, H5, T and n are all known numbers; the disconnection instruction sending time of the closing resistance gap trigger module is H6, H6>2ms.

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