CN210838466U - Vacuum circuit breaker control circuit for 10kV capacitor - Google Patents
Vacuum circuit breaker control circuit for 10kV capacitor Download PDFInfo
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- CN210838466U CN210838466U CN201921346301.4U CN201921346301U CN210838466U CN 210838466 U CN210838466 U CN 210838466U CN 201921346301 U CN201921346301 U CN 201921346301U CN 210838466 U CN210838466 U CN 210838466U
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Abstract
The utility model discloses a vacuum circuit breaker control circuit for 10kV capacitor, including closing a floodgate return circuit and separating brake return circuit, the closing a floodgate return circuit includes first supplementary sub-switch QF1, coil RO, relay KO, combined floodgate coil HQ, energy storage travel switch S1, second supplementary sub-switch QF 2; the opening loop comprises a third auxiliary sub-switch QF3, a first end of the third auxiliary sub-switch QF3 is connected with the opening coil TQ. The control circuit disconnection fault caused by diode damage due to frequent operation of reactive compensation device switching and switching can be effectively avoided, the reliability of safe and stable operation of the capacitor bank in the transformer substation is greatly improved, the reliability of equipment is improved, the reliability of power supply is guaranteed, and the cost of operation and maintenance personnel is reduced.
Description
Technical Field
The utility model belongs to the technical field of vacuum circuit breaker control circuit, concretely relates to vacuum circuit breaker control circuit for 10kV condenser.
Background
According to statistics, the circuit breaker control circuit disconnection defects of the 10kV reactive compensation device capacitor bank used in the 110kV transformer substation used at present are up to 8 in a year, so that the safety and stability of equipment are greatly threatened, unnecessary work is added to operation and maintenance personnel, and the operation and maintenance cost is invisibly increased. The relay protection professional handles the defect on site every time, the reason is that the rectifying element on the PCD plate in the circuit breaker control circuit of the type is in fault, the control circuit is reset after a new plate is replaced, and the defect is eliminated. The reasons of the control circuit disconnection defects are summarized and analyzed, and two reasons of the control circuit disconnection are found, namely, the circuit breaker controls the power supply to be in a disconnection state, and the circuit breaker is opened when the power supply is closed and opened, so that obvious short circuit phenomenon occurs; and secondly, the control loop of the opening and closing loop is broken. The circuit breakers of the 4 groups of capacitors are all in-cabinet handcart type circuit breakers of ZN63A-12(VS1) model. The control loop of the circuit breaker comprises a bridge rectifier. The main function of the bridge rectifier is to rectify the ac into dc and provide power to the circuit breaker actuator.
The control loop is broken due to the diode element of the bridge rectifier being damaged. The main reason is that the capacitor reactive compensation device is frequently operated, and generates large impact voltage and current when switching on and off, which can cause the short circuit or the open circuit of the diode to cause partial fault of the bridge rectifier, thus causing the interruption of the control power supply of the breaker, increasing the fault rate of the equipment and influencing the normal operation of the power supply.
The bridge rectifier is actually composed of 4 diodes, has the function of converting an alternating current power supply into a direct current power supply through rectification of the 4 diodes, provides a power supply for a circuit breaker operating mechanism, is mainly used in the occasions without direct current power supplies and other equipment in an early transformer substation, and is converted into the direct current power supply through alternating current rectification for switching on and off of a circuit breaker, a motor loop and the like. However, because the circuit breaker control system is provided with the rectifying circuit, a possible fault point is added, the operation fault rate of the circuit breaker is improved, the field maintenance is inconvenient, the procurement period of a fault part is long, and the power supply reliability is seriously influenced when the fault occurs, so that the existing circuit breaker control circuit needs to be improved.
Disclosure of Invention
In order to solve the problem, the utility model provides a 10kV is vacuum circuit breaker control circuit for condenser no longer sets up bridge type rectifier in the control circuit, greatly reduced circuit breaker operational failure rate, and then improved the power supply reliability.
To achieve the above object, the present invention provides a control circuit of a vacuum circuit breaker for a 10kV capacitor, comprising a closing circuit and an opening circuit, wherein the closing circuit comprises a first auxiliary sub-switch QF1, the first auxiliary sub-switch QF1 is connected with a contact k, the contact k and a contact l are a pair of contacts, the contact l is connected with a first end of a coil RO, a second end of the coil RO is connected with a second end of a coil of a relay KO, a first end of the coil of the relay KO is connected with a first end of a closing coil HQ and a contact b, the contact b and a are a pair of contacts, a second end of the closing coil HQ is connected with a first end of an energy storage stroke switch S1, a second end of the energy storage stroke switch S1 is connected with a first end of a second auxiliary sub-switch QF2, a second end of the second auxiliary switch QF2 is connected with a normally closed contact of the relay KO through a latching coil auxiliary contact S, a normally open contact of the relay KO is connected with a first end of a first auxiliary sub-switch QF1, and a movable contact of the relay KO is connected with a second end of the first auxiliary sub-switch QF 1;
the opening loop comprises a third auxiliary sub-switch QF3, and a first end of the third auxiliary sub-switch QF3 is connected with an opening coil TQ.
Further, the latching circuit comprises a fourth auxiliary sub-switch QF4, a first end of the fourth auxiliary sub-switch QF4 is connected with a first end of a resistor R1 through a contact q, a second end of the resistor R1 is connected with a latching coil Y1, the contact q and the contact p are a pair of contacts, and the contact p is connected with a second end of the resistor R1; the second terminal of the fourth auxiliary sub-switch QF4 is connected to the switch S8 and the switch S9, and the latching coil Y1 is connected to the moving contact of the latching coil auxiliary contact S.
And further, the circuit also comprises a motor loop, wherein the motor loop comprises an energy storage travel switch S1, an energy storage travel switch S2, an energy storage travel switch S3 and an energy storage travel switch S4 which are connected in parallel, the energy storage travel switch S2 is connected with an energy storage motor M in series, and the energy storage motor M is used for driving an energy storage spring to act to complete the switching-on or switching-off of the contact of the circuit breaker.
Further, still include electrified indicating contact, electrified indicating contact and electrified pilot lamp are connected, and electrified indicating contact is normally open contact, and the circuit breaker is combined floodgate back, and normally open contact is closed, and electrified pilot lamp is bright.
The motor energy storage contact is connected with the motor energy storage indicating lamp; when the switch is closed, the energy storage indicator lamp of the motor is lightened.
Furthermore, the device also comprises a test position microswitch and a working position microswitch, wherein the test position microswitch and the working position microswitch are used for providing a position signal of the circuit breaker.
Compared with the prior art, the utility model discloses following profitable technological effect has at least, vacuum circuit breaker has a short-lived charging process in the twinkling of an eye to the condenser input, and this process is a transient state process who is equivalent to the short circuit, to just in time being in the phase place of higher voltage, has very big impulse current to flow through the switch contact, simultaneously, because the existence of current-limiting reactor, will vibrate because of the resistance-capacitance and produce very high harmonic overvoltage, this is the root cause that causes electric arc doubling increase. The capacitor bank is charged before being disconnected, the capacitor bank has a certain voltage, the switch is disconnected after receiving a switching-off command, electric arcs are extinguished, an external line is alternating-current voltage with polarity changing constantly along with time, and therefore the switch is subjected to reverse voltage after being disconnected, a fracture of the switch can bear twice of normal line voltage to the maximum extent, the capacitor reactive power compensation device is frequently operated, and large impact voltage and current can be generated during switching and cutting, and a diode can be caused to be short-circuited or disconnected. Through the optimal design of the control circuit of the circuit breaker, after a bridge rectifier in the control circuit is cancelled, the disconnection fault of the control circuit caused by the damage of a diode, which is caused by frequent switching and cutting operations of a reactive compensation device, can be effectively avoided, the reliability of safe and stable operation of a capacitor bank in a substation is greatly improved, the reliability of equipment is improved, the reliability of power supply is ensured, and the cost of operation and maintenance personnel is reduced. The use requirement is met, the performance and the reliability of the bridge rectifier are improved, meanwhile, the purchase cost and the overhaul cost of the bridge rectifier are saved, and the purchase cost is reduced.
Drawings
Fig. 1 is a circuit diagram of the control circuit of the present invention.
In the drawings: HQ is a closing coil, TQ is an opening coil, M is an energy storage motor, QF is an auxiliary switch, S is an auxiliary contact of a locking coil, S1-S4 are energy storage travel switches, S8 is a travel switch for linkage, S9 is a travel switch for linkage, and Y1 is a locking coil.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
The terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships that are based on the orientations or positional relationships shown in the drawings, and are merely for convenience in describing and simplifying the present invention, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
At present, a substation is generally provided with a DC screen, the DC screen can be used for providing power for a circuit breaker operating mechanism, and terminals 1 and 2 of an auxiliary switch are connected with a DC screen power supply. In the control loop of the 10kV capacitor circuit breaker, a rectification loop is cancelled.
Referring to fig. 1, a vacuum circuit breaker control circuit for a 10kV capacitor includes 4 circuits of cores: the device comprises a motor loop, a separating brake loop, a closing loop and a locking loop.
The motor loop is used for providing energy for a spring operating mechanism of the circuit breaker, and the motor drives the energy storage spring to complete energy required by opening and closing of a contact of the circuit breaker in a compression and release mode, namely, electric energy is converted into mechanical energy.
The opening circuit is used for opening, an opening button is arranged on a general control panel to give an instruction, and in an automatic operation state, signals are given through a microcomputer protection device at present, such as in the case of electrical faults of protected equipment.
The closing loop is used for closing and gives an instruction by a closing button on the control panel.
The locking loop is used for interlocking of more than two circuit breakers, and at present, important loads are provided with two incoming lines, namely two power supplies, one standby power supply generally uses one power supply for power supply, so that the circuit breakers need to be subjected to interlocking control.
The motor circuit comprises an energy storage travel switch S1, an energy storage travel switch S2, an energy storage travel switch S3 and an energy storage travel switch S4 which are connected in parallel, wherein the energy storage motor M is connected with the energy storage travel switch S2 in series.
The switching-on loop comprises a first auxiliary sub switch QF1, a first end of the first auxiliary sub switch QF1 is connected with a No. 14 wiring terminal, a second end of the first auxiliary sub switch QF1 is connected with a contact k, a contact l is connected with a first end of a coil RO, a second end of the coil RO is connected with a second end of a coil of a relay KO, the first end of the coil of the relay KO is connected with a first end of a switching-on coil HQ and a contact b, the contact a is connected with the No. 4 wiring terminal, the contact b and the contact a are a pair of contacts, the second end of the switching-on coil HQ is connected with a first end of an energy storage travel switch S1, a second end of an energy storage travel switch S1 is connected with a first end of a second auxiliary sub switch QF2, the second end of a second auxiliary switch QF2 is connected with a normally closed contact of the relay KO through a locking coil auxiliary contact S, a normally open contact of the relay KO is connected with a first end of the first auxiliary sub switch QF1, and a movable. Wherein the latching coil auxiliary contact S is energized by the latching coil Y1.
The locking loop comprises a fourth auxiliary sub-switch QF4, a first end of the fourth auxiliary sub-switch QF4 is connected with a first end of a resistor R1 through a contact q, a second end of the resistor R1 is connected with a locking coil Y1, and the contact p and the contact q are a pair of contacts; in the initial state, the middle between the contact p and the contact q is opened, and the contact p and the contact q are flexibly changed for customer needs: if the customer wants the circuit breaker not to have the locking function, the middle of the contact p and the contact q is disconnected, and if the customer wants to have the locking function, the contact p and the contact q are connected; the second terminal of the fourth auxiliary sub-switch QF4 is connected to the first terminal of the switch S8 and the first terminal of the switch S9, the second terminal of the switch S8 is connected to the No. 53 connection terminal, and the second terminal of the switch S9 is connected to the No. 54 connection terminal.
The brake separating loop comprises a third auxiliary sub-switch QF3, the first end of the third auxiliary sub-switch QF3 is connected with the connecting terminal 31 through a brake separating coil TQ, the first end of the third auxiliary sub-switch QF3 is also connected with the No. 41 connecting terminal, and the second end of the third auxiliary sub-switch QF3 is connected with the No. 30 connecting terminal.
The auxiliary switch QF comprises a first auxiliary sub-switch QF1, a second auxiliary sub-switch QF2, a third auxiliary sub-switch QF3 and a fourth auxiliary sub-switch QF4, wherein the first auxiliary sub-switch QF1 and the third auxiliary sub-switch QF3 are normally closed switches, and the second auxiliary sub-switch QF2 and the fourth auxiliary sub-switch QF4 are normally open switches.
Preferably, the control circuit of the vacuum circuit breaker for the 10kV capacitor further comprises a motor circuit, an auxiliary circuit and other auxiliary contacts.
The auxiliary circuit provides an auxiliary contact, and the actions of switching on and off and storing energy are executed, and a plurality of normally open and normally closed contacts are required to be connected in series to achieve the purpose of logic control. In addition, after the circuit breaker is switched on, the circuit is electrified, the circuit is expected to indicate that the switched-on circuit is electrified, at this time, a normally open contact of the auxiliary switch can be used for giving a signal to an indicator lamp on the panel, and after the circuit breaker is switched on, the normally open contact is closed, the indicator lamp is on, the work is told, and the equipment is electrified.
Be provided with motor energy storage contact on the control circuit, experimental position micro-gap switch and operating position micro-gap switch, motor energy storage contact is used for connecting motor energy storage pilot lamp, motor energy storage pilot lamp lights after spring mechanism energy storage is accomplished, experimental position and operating position micro-gap switch are used for providing the position signal of circuit breaker, the circuit breaker mainly has three kinds of positions, the first kind is operating position (the circuit breaker impels the back in place, once with secondary system all with the return circuit switch-on), the second kind is experimental position (the circuit breaker once with system separation, the secondary is put through with system switch-on), the third kind is maintenance position (the circuit breaker is released the back, once with secondary system all with the return circuit disconnection), position signal transmission and spacing are realized through the travel switch linkage of circuit breaker handcart and the internal portion of cabinet to various operating positions of circuit.
The working process of the control loop is as follows:
when the breaker is switched on, the operating mechanism spring is already in a compressed state, when an operator gives a breaker switching-on command (for example, presses a switching-on button), the switching-on button switches on an electric loop of a switching-on electromagnet, a switching-on coil HQ is electrified and is quickly sucked, so that an ejector rod on the switching-on coil HQ is separated from a clamping position, a pressing plate of a compression spring is released, and the spring drives a breaker transmission mechanism through the mechanism to complete switching-on action of a breaker vacuum bubble; meanwhile, the breaker automatically completes the spring compression and energy storage actions of the operating mechanism through the energy storage motor, and prepares for next brake opening.
In the switching-on process, the S1 is an energy storage travel switch, only after energy storage is completed, the S1 contact can be closed to indicate that the energy storage is completed, the switching-on condition is met, the QF1 is closed, the QF2 is disconnected, the S switch is closed, the latching electromagnet is electrified, and the anti-jump relay KO is electrified.
When the breaker is opened, the operating mechanism spring is already in a compressed state, when an operator gives a breaker opening command (for example, presses the opening button), the opening button switches on an electric loop of the opening electromagnet, the opening coil TQ is electrified and is quickly attracted, so that the ejector rod above the closing coil TQ is separated from a clamping position, a pressing plate of the pressing spring is released, and the spring drives the breaker transmission mechanism to perform the opening action with the vacuum bubble of the breaker through the mechanism. Meanwhile, the breaker automatically completes the compression of the spring of the operating mechanism and the energy storage action through the energy storage motor, and prepares for the next closing.
The electromagnetic lock is to utilize the auxiliary contacts of the breaker, the switch cabinet door and the like to connect or disconnect the electromagnetic lock power supply of the breaker, the switch cabinet door and the like which need to be locked, so that the operation mechanism can not act, and the mutual lock between the switch devices is realized. The circuit breaker is mainly used for preventing mistaken separation and mistaken closing.
The control circuit of the circuit breaker is tested, the functions of the opening circuit, the closing circuit, the motor circuit and the locking circuit of the circuit breaker are normal, the use is not influenced, characteristic tests of the circuit breaker are performed, including tests of voltage of a loop resistance coil, a closing coil and the like, relevant regulation requirements are met, the improved circuit breaker is good in operation condition after being put into operation, and the failure rate is greatly reduced.
The utility model discloses to the excessive pressure operating mode characteristics of vacuum circuit breaker cut-off capacitor bank, through to handcart-type circuit breaker control circuit in the cabinet, can effectively avoid reactive power compensator to throw, cut the control circuit broken string trouble that frequent operation leads to because the diode damages, improved the reliability of the safe and stable operation of this transformer substation capacitor bank greatly, improved the reliability of equipment, ensured the reliability of supplying power, reduced fortune dimension cost of personnel simultaneously.
Claims (6)
1. The vacuum circuit breaker control circuit for the 10kV capacitor is characterized by comprising a closing circuit and an opening circuit, wherein the closing circuit comprises a first auxiliary sub-switch QF1, the first auxiliary sub-switch QF1 is connected with a contact k, the contact k and a contact l are a pair of contacts, the contact l is connected with a first end of a coil RO, a second end of the coil RO is connected with a second end of a coil of a relay KO, the first end of the coil of the relay KO is connected with a first end of a closing coil HQ and a contact b, the contact b and the contact a are a pair of contacts, the second end of the coil HQ is connected with a first end of an energy storage travel switch S1, the second end of the energy storage travel switch S1 is connected with a first end of a second auxiliary sub-switch QF2, the second end of the second auxiliary switch QF2 is connected with a normally closed contact of the relay KO through an auxiliary contact S of a locking coil, and a normally open contact of the relay KO is connected with a first end of a first auxiliary sub-switch Q, the movable contact of the relay KO is connected with the second end of the first auxiliary sub-switch QF 1;
the opening loop comprises a third auxiliary sub-switch QF3, and a first end of the third auxiliary sub-switch QF3 is connected with an opening coil TQ.
2. The control circuit of a vacuum circuit breaker for a 10kV capacitor as claimed in claim 1, further comprising a latching circuit, wherein the latching circuit comprises a fourth auxiliary sub-switch QF4, a first end of the fourth auxiliary sub-switch QF4 is connected with a first end of a resistor R1 through a contact q, a second end of the resistor R1 is connected with a latching coil Y1, the contact q and the contact p are a pair of contacts, and the contact p is connected with a second end of the resistor R1; the second terminal of the fourth auxiliary sub-switch QF4 is connected to the switch S8 and the switch S9, and the latching coil Y1 is connected to the moving contact of the latching coil auxiliary contact S.
3. The control circuit of the vacuum circuit breaker for the 10kV capacitor as claimed in claim 1, further comprising a motor circuit, wherein the motor circuit comprises an energy storage travel switch S1, an energy storage travel switch S2, an energy storage travel switch S3 and an energy storage travel switch S4 which are connected in parallel, the energy storage travel switch S2 is connected in series with an energy storage motor M, and the energy storage motor M is configured to drive an energy storage spring to act to complete the closing or opening of the contacts of the circuit breaker.
4. The vacuum circuit breaker control circuit for the 10kV capacitor as claimed in claim 1, further comprising a live indicating contact, wherein the live indicating contact is connected with a live indicating lamp, the live indicating contact is a normally open contact, and after the circuit breaker is switched on, the normally open contact is closed and the live indicating lamp is turned on.
5. The control circuit of the vacuum circuit breaker for the 10kV capacitor as claimed in claim 1, further comprising a motor energy storage contact, wherein the motor energy storage contact is connected with a motor energy storage indicator lamp; when the switch is closed, the energy storage indicator lamp of the motor is lightened.
6. The control circuit of a vacuum circuit breaker for a 10kV capacitor of claim 1, further comprising a trial position microswitch and a working position microswitch, the trial position and working position microswitch being used for providing a position signal of the circuit breaker.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921346301.4U CN210838466U (en) | 2019-08-19 | 2019-08-19 | Vacuum circuit breaker control circuit for 10kV capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921346301.4U CN210838466U (en) | 2019-08-19 | 2019-08-19 | Vacuum circuit breaker control circuit for 10kV capacitor |
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| Publication Number | Publication Date |
|---|---|
| CN210838466U true CN210838466U (en) | 2020-06-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921346301.4U Active CN210838466U (en) | 2019-08-19 | 2019-08-19 | Vacuum circuit breaker control circuit for 10kV capacitor |
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| CN (1) | CN210838466U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116110753A (en) * | 2023-04-11 | 2023-05-12 | 宁波天安智能电网科技股份有限公司 | Adjustable breaker safety loop system |
-
2019
- 2019-08-19 CN CN201921346301.4U patent/CN210838466U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116110753A (en) * | 2023-04-11 | 2023-05-12 | 宁波天安智能电网科技股份有限公司 | Adjustable breaker safety loop system |
| CN116110753B (en) * | 2023-04-11 | 2023-07-04 | 宁波天安智能电网科技股份有限公司 | Adjustable breaker safety loop system |
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Effective date of registration: 20230711 Address after: 678400 No.96 KuoShi Road, Mangshi, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province Patentee after: YUNNAN POWER GRID Co.,Ltd. DEHONG POWER SUPPLY BUREAU Address before: No. 96, Kuoshi Road, Mangshi, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan 678499 Patentee before: YUNNAN POWER GRID Co.,Ltd. DEHONG POWER SUPPLY BUREAU Patentee before: NINGBO TIANAN EQUIPMENT INSTALLATION ENGINEERING Co.,Ltd. |