CN219458655U - Anti-burning loop for tripping and closing coil - Google Patents
Anti-burning loop for tripping and closing coil Download PDFInfo
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- CN219458655U CN219458655U CN202320333703.0U CN202320333703U CN219458655U CN 219458655 U CN219458655 U CN 219458655U CN 202320333703 U CN202320333703 U CN 202320333703U CN 219458655 U CN219458655 U CN 219458655U
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Abstract
The utility model provides a tripping and closing coil burnout prevention loop, which comprises a protection control loop, a tripping hold-up relay, a closing hold-up relay and a time relay, wherein the protection control loop comprises a closing loop and a tripping loop, the closing loop is provided with a breaker closing coil, the tripping loop is provided with a breaker tripping coil, the time relay is used for delaying to control the closing hold-up relay to lose electricity, so that a first normally open contact of the closing hold-up relay is disconnected, the breaker closing coil is further prevented from being burnt out, the time relay is used for delaying to control the tripping hold-up relay to lose electricity, so that the first normally open contact of the tripping hold-up relay is disconnected, and further, the breaker tripping coil is prevented from being burnt out, thereby realizing the protection to the tripping and closing coil.
Description
Technical Field
The application belongs to the technical field of tripping and closing coil protection, and particularly relates to a tripping and closing coil burnout prevention loop.
Background
The transformer substation breaker is a switching device capable of switching on, carrying and off current under normal loop conditions and switching on, carrying and off current under abnormal loop conditions within a specified time; the closing of the circuit breaker is realized through a secondary control loop of the circuit breaker, and the tripping and closing loops in the secondary control loop of the circuit breaker are conducted to enable the tripping and closing coils to be electrified to enable the circuit breaker to be closed.
The tripping and closing coil of the circuit breaker burns out as follows:
1. and the brake-separating electromagnet has mechanical failure. The coil looseness causes the displacement of the electromagnet when the breaker is opened, so that the iron core is blocked, and the coil is burnt; or because the movable stroke of the iron core is short, when the switching-on and switching-off loop power supply is switched on, the iron core top does not open the tripping mechanism so that the coil is electrified for a long time to burn out.
2. The circuit breaker refuses to be separated. When the control loop is normal, the faults of refusal of the circuit breaker are all problems of a connecting rod mechanism, such as improper vertex adjustment, so that the force of the ejector rod of the brake-separating iron core of the circuit breaker cannot timely release the mechanism; or the coil is overloaded due to the fact that the protective locking mechanism is not operated, so that the brake-separating coil is burnt.
3. The stroke adjustment of the auxiliary switch in the opening state is improper. When the breaker is in the opening state, the auxiliary switch should be adjusted to be in the stroke range of the opening state. However, when parameters such as the opening distance and the over-travel of the circuit breaker are adjusted, the initial state of the opening of the circuit breaker is not adjusted correspondingly, so that the auxiliary switch cannot normally switch the opening loop, and the opening coil is burnt.
4. The opening control loop assists the improper use of the switch contacts. When the switching-on time of the circuit breaker is extremely short and is far smaller than the switching-off time of the circuit breaker, the circuit breaker is switched on in place after being tripped, and the time delay effect of the time delay contact point is meaningless. In contrast, in the switching-off process of the time delay contact, because the insulation gap of the moving contact and the fixed contact of the auxiliary switch is smaller, an arcing phenomenon often occurs, the contact of the auxiliary switch is burnt out, and then a switching-off coil is burnt out.
5. The protection control device malfunctions. The opening command is sent by the protection control device, and if the opening relay in the device has a fault or the action stroke of the auxiliary switch contact of the opening control loop is larger, the opening command cannot be withdrawn in time, and the opening coil is electrified for a long time to burn out.
6. The resistance of the opening loop is larger. The insulation of the opening coil loop is reduced, or the resistance is larger due to the too small wire diameter of the control loop, so that the voltage drop of the opening control loop is larger, the voltage cannot reach the value of the opening action of the coil, and the opening coil is burnt out in a long-time electrified manner.
Based on the above situation, the utility model provides an anti-burnout loop of a tripping and closing coil.
Disclosure of Invention
The embodiment of the application provides a tripping and closing coil burnout prevention loop, which is connected in series with a time relay coil to be connected into a protection control loop power supply after a tripping hold-down relay normally open contact and a closing hold-down relay normally open contact are connected in parallel, and the normally closed contact of the time relay is connected in series into a tripping loop, so that tripping and closing coil protection is realized, and the problem that tripping and closing coils burnout is caused because an auxiliary switch contact of a circuit breaker cannot be disconnected is solved.
The embodiment of the application provides a tripping and closing coil burnout prevention loop, which comprises a protection control loop, a tripping hold relay, a closing hold relay and a time relay;
the protection control loop comprises a closing loop and a tripping loop, wherein the closing loop is provided with a breaker closing coil, and the tripping loop is provided with a breaker tripping coil;
after the second normally open contact of the tripping hold-down relay is connected in parallel with the second normally open contact of the closing hold-down relay, the coils of the time relay are connected in series to form a time relay trigger circuit, and the time relay trigger circuit is connected into a power supply of the protection control loop;
the coil of the closing holding relay, the first normally open contact of the closing holding relay and the first normally closed contact of the time relay are all connected in series to the closing loop;
the coil of the trip holding relay, the first normally open contact of the trip holding relay and the second normally closed contact of the time relay are all connected in series to the trip circuit;
the time relay is used for controlling the switching-on maintaining relay to lose electricity in a time delay manner, so that a first normally open contact of the switching-on maintaining relay is disconnected, and further, a switching-on coil of the circuit breaker is powered off and reset to prevent the switching-on coil from being burnt;
the time relay is also used for controlling the tripping hold-down relay to lose electricity in a time delay manner, so that the first normally open contact of the tripping hold-down relay is disconnected, and further the tripping coil of the circuit breaker is powered off and reset to prevent the tripping coil from being burnt.
In a possible implementation manner, the protection control circuit further comprises a hand-closing circuit, a reclosing circuit and a remote-closing circuit, wherein the hand-closing circuit, the reclosing circuit and the remote-closing circuit are all electrically connected with the closing circuit;
when any loop in the manual loop, the reclosing loop and the remote loop is electrified and triggered, a first normally open contact of the closing holding relay is closed, the closing loop is conducted, the closing coil of the circuit breaker is electrified, meanwhile, a second normally open contact of the closing holding relay is closed, the time relay is conducted, a first normally closed contact of the time relay is opened in a delayed mode, and the closing coil of the circuit breaker is powered off and reset.
In a possible implementation manner, the protection control circuit further comprises a hand-tripping circuit, a protection tripping circuit, a remote tripping circuit and a perpetual tripping circuit, wherein the hand-tripping circuit, the protection tripping circuit, the remote tripping circuit and the perpetual tripping circuit are all electrically connected with the tripping circuit;
when any loop in the hand trip loop, the protection trip loop, the remote trip loop and the permanent trip loop is electrified and triggered, the first normally open contact of the tripping holding relay is closed, the tripping loop is conducted, the tripping coil of the circuit breaker is electrified and acts, meanwhile, the second normally open contact of the tripping holding relay is closed, the time relay is conducted, the second normally closed contact of the time relay is opened in a delayed mode, and the tripping coil of the circuit breaker is powered off and reset.
In one possible implementation manner, the fixed delay time of the time relay is T, the normal closing time of the circuit breaker is T1, and the normal tripping time of the circuit breaker is T2, so that T is more than or equal to T1, and T is more than or equal to T2.
In one possible implementation, the protection control loop further includes a power supply that powers each loop.
In one possible implementation, the power supply is provided with a power switch.
In one possible implementation, the power source is a dc power source.
According to the tripping and closing coil burnout prevention loop, after the second normally open contact of the tripping holding relay is connected in parallel with the second normally open contact of the closing holding relay, the coil of the time relay is connected in series, so that the time relay trigger circuit is connected into a power supply of the protection control loop, the coil of the tripping holding relay, the first normally open contact of the tripping holding relay and the first normally closed contact of the time relay are connected in series into the closing loop, the coil of the tripping holding relay, the first normally open contact of the tripping holding relay and the second normally closed contact of the time relay are connected in series into the tripping loop, the time relay delays to control the switching holding relay to lose electricity, the first normally open contact of the breaker is disconnected, the tripping coil of the breaker is disconnected to reset to prevent burnout, the time relay delays to control the tripping holding relay to lose electricity, the first normally open contact of the tripping holding relay is disconnected, and the tripping coil of the breaker is disconnected to reset to prevent burnout, and thus the tripping and coil burnout problem of the tripping holding relay is solved.
Drawings
Fig. 1 is a circuit diagram of a tripping and closing coil burnout prevention loop provided by the application.
Detailed Description
In order to better understand the technical solutions in the present application, the following description will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present application.
Referring to fig. 1, a circuit diagram of a burnout prevention loop of a tripping and closing coil is shown, wherein components in the circuit diagram include; TBJ-trip hold relay; TBJ1 —a first normally open contact of a trip hold relay; TBJ2 —a second normally open contact of the trip hold relay; hbj—closing hold relay; HBJ1- -the first normally open contact of the closing hold relay; HBJ2- -the second normally open contact of the closing hold relay; sj—time relay; SJ1—the first normally closed contact of the time relay; SJ2—the second normally closed contact of the time relay; TWJ1, TWJ2—trip position relays; HWJ1, HWJ2 —closing position relay; TBJV- -anti-trip relay; kkj—post-closing position relay; STJ- -hand-skip relay; TJR-permanent trip relay; hq—a closing coil; tq—trip coil; DL 1-a first auxiliary switch contact; DL 2-second auxiliary switch contact.
The embodiment of the application provides a tripping and closing coil burnout prevention loop, which comprises a protection control loop, a tripping hold relay TBJ, a closing hold relay HBJ and a time relay SJ;
the protection control loop comprises a closing loop and a tripping loop, wherein the closing loop is provided with a breaker closing coil HQ, and the tripping loop is provided with a breaker tripping coil TQ.
The tripping holding relay TBJ second normally open contact TBJ is connected in parallel with the switching-on holding relay HBJ second normally open contact HBJ2 and then is connected in series with a time relay SJ coil to form a time relay trigger circuit, and the time relay trigger circuit is connected into a protection control loop power supply;
the coil of the closing holding relay HBJ, the first normally-open contact HBJ1 of the closing holding relay and the first normally-closed contact SJ1 of the time relay are all connected in series to a closing loop, and the coil of the tripping holding relay TBJ, the first normally-open contact TBJ1 of the tripping holding relay and the second normally-closed contact SJ2 of the time relay are all connected in series to a tripping loop;
after switching on, the time relay SJ delays to control the switching-on maintaining relay HBJ to lose electricity, so that a first normally open contact HBJ1 of the switching-on maintaining relay is disconnected, and further, a switching-on coil HQ of the circuit breaker is powered off and reset, and burning is prevented;
after tripping, the time relay SJ delays to control the tripping hold relay TBJ to lose power, so that the first normally open contact TBJ of the tripping hold relay is opened, and further the tripping coil TQ of the circuit breaker is powered off and reset, and the circuit breaker is prevented from being burnt.
According to the tripping and closing coil burnout prevention loop, after the second normally open contact TBJ of the tripping maintaining relay is connected with the second normally open contact HBJ2 of the closing maintaining relay in parallel, the coils of the time relay SJ are connected in series to form a time relay trigger circuit, the time relay trigger circuit is connected into a power supply of a protection control loop, the coils of the closing maintaining relay HBJ, the first normally open contact HBJ1 of the closing maintaining relay and the first normally closed contact SJ1 of the time relay are connected in series to the closing loop, the coils of the tripping maintaining relay TBJ, the first normally open contact TBJ of the tripping maintaining relay and the second normally closed contact SJ2 of the time relay are connected in series to the tripping loop, the time relay SJ is enabled to delay to control the switching maintaining relay HBJ to lose electricity, the first normally open contact HBJ1 of the switching maintaining relay is enabled to be disconnected, the switching coil HQ of the circuit breaker is enabled to be reset to prevent from being burnt out, the time relay SJ is enabled to delay to control the tripping maintaining relay HBJ TBJ to lose electricity, the first normally open contact TBJ of the tripping maintaining relay is enabled to be disconnected, and the tripping relay is enabled to be disconnected to prevent the normally open coil of the tripping relay from being broken, and the problem is solved.
Referring to fig. 1, in some embodiments, the protection control circuit further includes a hand-on circuit, a reclosing circuit, and a remote-on circuit, when the hand-on circuit, the reclosing circuit, and the remote-on circuit are closed, the first contact HBJ1 of the closing holding relay is closed, the closing coil HQ of the circuit breaker is electrified after the closing circuit is always conducted, when the contact DL1 is opened after the circuit breaker is closed, the closing holding relay HBJ is powered off, the contact HBJ1 of the closing holding relay is opened, the closing coil HQ of the circuit breaker is powered off and reset, and if the circuit breaker cannot be closed for various reasons, the auxiliary switch contact DL1 cannot be opened, the closing circuit is always conducted until the closing coil HQ is electrified and burned out for a long time;
the switching-on maintaining relay HBJ is enabled to act when the switching-on maintaining relay is switched on, reclosing and remote-control, the first normally open contact HBJ1 of the switching-on maintaining relay is closed, the switching-on coil HQ of the circuit breaker is enabled to act in a charged mode after the switching-on loop is always conducted, the second normally open contact HBJ2 of the switching-on maintaining relay is closed at the moment, the time relay SJ is enabled to be conducted, the auxiliary switch contact DL1 cannot be disconnected when the circuit breaker cannot be switched on, the switching-on loop can be always conducted, the time relay is enabled to be disconnected in a delayed mode, the switching-on maintaining relay HBJ is powered off, the first normally open contact HBJ1 of the switching-on maintaining relay is disconnected, the switching-on coil HQ of the circuit breaker is powered off and reset, the switching-on coil HQ is prevented from being burnt, the switching-on maintaining relay HBJ2 is disconnected, and the time relay SJ is powered off and reset.
The protection control loop further comprises a hand-jump loop, a protection jump loop, a remote jump loop and a permanent jump loop, wherein the hand-jump loop, the protection jump loop, the remote jump loop and the permanent jump loop are electrically connected with the tripping loop;
when the tripping relay TBJ acts, the first normally open contact TBJ of the tripping relay is closed, so that the tripping coil TQ of the circuit breaker acts in a charged manner after the tripping circuit is always conducted, when the DL2 contact is disconnected after the circuit breaker trips, the tripping relay TBJ is powered off, the contact TBJ1 of the tripping relay TBJ is disconnected, and the tripping coil TQ of the circuit breaker is powered off and reset, if the circuit breaker cannot trip due to various reasons, the auxiliary switch contact DL2 cannot be disconnected until the tripping coil is charged and burnt for a long time;
the trip-keeping relay TBJ is enabled to act when the trip-keeping relay is in a tripping state, the protection trip, the remote trip and the permanent trip are performed, the trip-keeping relay first normally-open contact TBJ1 is closed to enable the tripping circuit to conduct all the time, then the breaker tripping coil TQ is electrified, the trip-keeping relay second normally-open contact TBJ2 is closed to enable the time relay SJ to conduct, when the breaker cannot trip, the auxiliary switch contact DL2 cannot be opened to enable the tripping circuit to conduct all the time, the time relay acts SJ2 to disconnect, the tripping-keeping relay TBJ loses electricity, the trip-keeping relay first normally-open contact TBJ1 is disconnected, the breaker tripping coil TQ is in a power-off reset state, the tripping coil TQ is prevented from being burnt, the trip-keeping relay TBJ contact TBJ2 is disconnected, and the time relay SJ is in a power-off reset state.
The fixed time delay of the time relay is T, the normal closing time of the circuit breaker is T1, and the normal tripping time of the circuit breaker is T2, wherein T is more than or equal to T1, and T is more than or equal to T2.
In some embodiments, the protection control loop further comprises a power supply, the power supply supplies power to each loop, a power switch is arranged on the power supply, and the power supply is a direct current power supply.
By the above-mentioned technical characteristics record, the trip, closing coil that this application provided prevents burning out return circuit theory of operation in the practical application scene does:
when the circuit breaker cannot be switched on due to various reasons, when the auxiliary switch contact DL1 cannot be switched off, the first normally open contact HBJ1 of the switching-on holding relay is closed, the switching-on coil HQ of the circuit breaker is electrified after the switching-on loop is always switched on, the second normally open contact HBJ2 of the switching-on holding relay is closed, the time relay SJ is switched on, the time relay SJ is delayed for T time, the first normally closed contact SJ1 is switched off, the switching-on holding relay HBJ is powered off, the first normally open contact HBJ1 of the switching-on holding relay is switched off, the switching-on coil HQ of the circuit breaker is powered off and reset, and the switching-on coil HQ is prevented from being burnt;
when the breaker cannot trip due to various reasons, when the auxiliary switch contact DL2 cannot be opened, the first normally open contact TBJ1 of the trip holding relay is closed, the trip coil TQ of the breaker is electrified after the trip circuit is always conducted, the second normally open contact TBJ2 of the trip holding relay is closed, the time relay SJ is conducted, after the time relay SJ is delayed for T time, the contact of the time relay SJ2 is opened, the trip holding relay TBJ is in power failure, the first normally open contact TBJ1 of the trip holding relay is opened, the trip coil TQ of the breaker is in power failure reset, and the trip coil TQ is prevented from being burnt;
the utility model has the remarkable advantages of simple structure, easy realization, effective prevention of the burning of the tripping and closing coils, small influence on the original control loop and the like.
It is to be understood that, based on the several embodiments provided in the present application, those skilled in the art may combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments, where none of the embodiments exceed the protection scope of the present application.
The foregoing detailed description of the embodiments of the present application has further described the objects, technical solutions and advantageous effects thereof, and it should be understood that the foregoing is merely a specific implementation of the embodiments of the present application, and is not intended to limit the scope of the embodiments of the present application, and any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the scope of the embodiments of the present application.
Claims (7)
1. The utility model provides a tripping and closing coil prevents burning out return circuit which characterized in that: the protection control circuit comprises a protection control loop, a tripping hold relay, a closing hold relay and a time relay;
the protection control loop comprises a closing loop and a tripping loop, wherein the closing loop is provided with a breaker closing coil, and the tripping loop is provided with a breaker tripping coil;
after the second normally open contact of the tripping hold-down relay is connected in parallel with the second normally open contact of the closing hold-down relay, the coils of the time relay are connected in series to form a time relay trigger circuit, and the time relay trigger circuit is connected into a power supply of the protection control loop;
the coil of the closing holding relay, the first normally open contact of the closing holding relay and the first normally closed contact of the time relay are all connected in series to the closing loop;
the coil of the trip holding relay, the first normally open contact of the trip holding relay and the second normally closed contact of the time relay are all connected in series to the trip circuit;
the time relay is used for controlling the switching-on maintaining relay to lose electricity in a time delay manner, so that a first normally open contact of the switching-on maintaining relay is disconnected, and further, a switching-on coil of the circuit breaker is powered off and reset to prevent the switching-on coil from being burnt;
the time relay is also used for controlling the tripping hold-down relay to lose electricity in a time delay manner, so that the first normally open contact of the tripping hold-down relay is disconnected, and further the tripping coil of the circuit breaker is powered off and reset to prevent the tripping coil from being burnt.
2. The trip and closing coil burnout prevention circuit according to claim 1, wherein:
the protection control loop further comprises a hand-closing loop, a reclosing loop and a remote closing loop, wherein the hand-closing loop, the reclosing loop and the remote closing loop are electrically connected with the closing loop;
when any loop in the manual loop, the reclosing loop and the remote loop is electrified and triggered, a first normally open contact of the closing holding relay is closed, the closing loop is conducted, the closing coil of the circuit breaker is electrified, meanwhile, a second normally open contact of the closing holding relay is closed, the time relay is conducted, a first normally closed contact of the time relay is opened in a delayed mode, and the closing coil of the circuit breaker is powered off and reset.
3. The trip and closing coil burnout prevention circuit according to claim 2, wherein:
the protection control loop further comprises a hand-tripping loop, a protection tripping loop, a remote tripping loop and a perpetual tripping loop, wherein the hand-tripping loop, the protection tripping loop, the remote tripping loop and the perpetual tripping loop are all electrically connected with the tripping loop;
when any loop in the hand trip loop, the protection trip loop, the remote trip loop and the permanent trip loop is electrified and triggered, the first normally open contact of the tripping holding relay is closed, the tripping loop is conducted, the tripping coil of the circuit breaker is electrified and acts, meanwhile, the second normally open contact of the tripping holding relay is closed, the time relay is conducted, the second normally closed contact of the time relay is opened in a delayed mode, and the tripping coil of the circuit breaker is powered off and reset.
4. The trip and closing coil burnout prevention circuit of claim 3, wherein:
the fixed time delay of the time relay is T, the normal closing time of the circuit breaker is T1, and the normal tripping time of the circuit breaker is T2, wherein T is more than or equal to T1, and T is more than or equal to T2.
5. The trip and closing coil burnout prevention circuit of claim 4, wherein:
the protection control loop also comprises a power supply, and the power supply supplies power to each loop.
6. The trip and closing coil burnout prevention circuit of claim 5, wherein:
the power supply is provided with a power switch.
7. The trip and closing coil burnout prevention circuit of claim 5, wherein:
the power supply is a direct current power supply.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320333703.0U CN219458655U (en) | 2023-02-28 | 2023-02-28 | Anti-burning loop for tripping and closing coil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320333703.0U CN219458655U (en) | 2023-02-28 | 2023-02-28 | Anti-burning loop for tripping and closing coil |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219458655U true CN219458655U (en) | 2023-08-01 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202320333703.0U Active CN219458655U (en) | 2023-02-28 | 2023-02-28 | Anti-burning loop for tripping and closing coil |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219458655U (en) |
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2023
- 2023-02-28 CN CN202320333703.0U patent/CN219458655U/en active Active
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