A main circuit breaker anti-tripping circuit and control method based on time delay relay

Abstract

The present invention provides a main circuit breaker anti-jump circuit and control method based on a time delay relay, which relates to the electrical field. The circuit includes a closing button SB1, a main circuit breaker normally closed contact QF1, a first normally closed contact K1', a main circuit breaker closing coil LC and a first relay coil KT1, which are connected in series in sequence, and the first normally open contact K1 is connected in parallel with a series circuit formed by the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1; an opening button SB2, a main circuit breaker normally open contact QF2, a second normally closed contact K2', a main circuit breaker opening coil LT and a second relay coil KT2 are connected in series in sequence; and the second normally open contact K2 is connected in parallel with a series circuit formed by the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker opening coil LT and the second relay coil KT2. The present application solves the main circuit breaker jumping problem under various fault conditions and has good engineering applicability.

Description

Technical Field

[0001] The present invention belongs to the field of electrical technology, and in particular to the field of direct current shore power supply, and in particular to a main circuit breaker anti-tripping circuit and a control method based on a time delay relay. Background Art

[0002] At present, after the circuit breaker is closed, due to some reasons, the closing contact is not restored (sticking, short circuit), when encountering equipment failure, the protection action will cause the circuit breaker to trip and there will be multiple "trip-close-trip-close" phenomena, which is called jumping phenomenon. The jumping phenomenon can easily damage the circuit breaker and cause the accident to expand. In order to prevent the occurrence of jumping phenomenon, an anti-trip circuit can be added to the circuit breaker mechanism or the internal control circuit of the protection device.

[0003] The existing anti-tripping circuit generally only handles the sticking of the closing switch of the main circuit breaker. At this time, it handles the situation where the closing switch is suddenly disconnected due to a fault after closing, or the closing failure occurs during opening. The sticking of the opening switch is not considered. At the same time, the existing anti-tripping circuit has the problem of complex structure.

[0004] Therefore, how to provide a main circuit breaker anti-tripping circuit based on a time delay relay has become a technical problem that urgently needs to be solved in this field. Summary of the invention

[0005] The object of the present invention is to provide a main circuit breaker anti-tripping circuit and a control method based on a time delay relay.

[0006] According to a first aspect of the present invention, there is provided a main circuit breaker anti-tripping circuit based on a time delay relay, comprising a closing button SB1, an opening button SB2, a first relay, a second relay, a main circuit breaker normally closed contact QF1, a main circuit breaker normally open contact QF2, a main circuit breaker closing coil LC and a main circuit breaker opening coil LT;

[0007] The main circuit breaker anti-tripping circuit includes a closing circuit and an opening circuit;

[0008] The closing circuit and the opening circuit are both arranged between the positive and negative electrodes;

[0009] The closing circuit comprises: a closing button SB1, a main circuit breaker normally closed contact QF1, a main circuit breaker closing coil LC and a first relay connected in series in sequence;

[0010] The opening circuit comprises: an opening button SB2, a main circuit breaker normally open contact QF2, a main circuit breaker opening coil LT and a second relay which are connected in series in sequence.

[0011] Optionally, the first relay includes a first relay coil KT1 and a first normally closed contact K1';

[0012] The closing button SB1, the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1 are connected in series in sequence.

[0013] Optionally, the first relay further includes a first normally open contact K1;

[0014] One end of the first normally open contact K1 is connected to the opening end of the normally closed contact QF1 of the main circuit breaker;

[0015] The other end of the first normally open contact K1 is connected to the tail end of the first relay coil KT1;

[0016] The first normally open contact K1 is connected in parallel with a series circuit formed by the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1.

[0017] Optionally, the second relay includes a second relay coil KT2 and a second normally closed contact K2';

[0018] The opening button SB2, the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker opening coil LT and the second relay coil KT2 are connected in series in sequence.

[0019] Optionally, the second relay further includes a second normally open contact K2;

[0020] One end of the second normally open contact K2 is connected to the opening end of the normally open contact QF2 of the main circuit breaker;

[0021] The other end of the second normally open contact K2 is connected to the tail end of the second relay coil KT2;

[0022] The second normally open contact K2 is connected in parallel with a series circuit formed by the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker tripping coil LT and the second relay coil KT2.

[0023] Optionally, the first relay is a time-delay relay, and the delay time is 5-30 seconds.

[0024] Optionally, the second relay is a time-delay relay, and the delay time is 5-30 seconds.

[0025] Optionally, the main circuit breaker closing coil LC controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2.

[0026] Optionally, the main circuit breaker tripping coil LT controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2.

[0027] According to a second aspect of the present invention, a control method for a main circuit breaker anti-tripping circuit based on a time delay relay is provided, using the main circuit breaker anti-tripping circuit based on a time delay relay as described in any one of the first aspects of the present invention;

[0028] When closing:

[0029] Press the closing button SB1, the closing circuit is energized, the main circuit breaker closing coil LC is energized, the main circuit breaker normally closed contact QF1 is disconnected, and the main circuit breaker normally open contact QF2 is closed. After the first relay reaches the preset time, the first relay coil KT1 is energized, and the first normally open contact K1 is closed, and the first normally closed contact K1' is disconnected;

[0030] When the closing button SB1 is stuck or short-circuited and has not been restored, if the equipment encounters a fault and the closing button SB1 trips or is normally opened, the main circuit breaker normally closed contact QF1 is closed and the main circuit breaker normally open contact QF2 is disconnected. Since the first normally closed contact K1' is disconnected at this time, the main circuit breaker closing coil LC loses power, and the closing button SB1 is connected to the first normally open contact K1 and is connected, avoiding the reclosing situation caused by the adhesion of the closing button SB1;

[0031] When opening:

[0032] When the opening button SB2 is pressed, the normally closed contact QF1 of the main circuit breaker is disconnected and the normally open contact QF2 of the main circuit breaker is closed. At this time, the opening circuit is energized, and the opening coil LT of the main circuit breaker is energized. At this time, the normally open contact QF2 of the main circuit breaker is disconnected and the normally closed contact QF1 of the main circuit breaker is closed. After the second relay reaches the set time, the coil KT2 of the second relay is energized. At this time, the second normally open contact K2 is closed and the second normally closed contact K2' is disconnected;

[0033] When the opening button SB2 is stuck, the opening button SB2 is connected to the second normally open contact K2 and a circuit is opened.

[0034] It can be seen from the above scheme that the embodiment of the present invention provides a main circuit breaker anti-tripping circuit based on a time delay relay, which has the following beneficial effects:

[0035] This application fully considers the sticking of the opening switch and the complex anti-jumping circuit structure. This application utilizes a power-on delay relay and a power-off delay relay to prevent the closing and opening contact jumping problem caused by switch sticking during closing and opening, and has good engineering applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The present invention is a schematic diagram of a main circuit breaker anti-tripping circuit based on a time delay relay provided according to an embodiment. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] like Figure 1 As shown, according to a first aspect of the present invention, a main circuit breaker anti-tripping circuit based on a time delay relay is provided, comprising a closing button SB1, an opening button SB2, a first relay, a second relay, a main circuit breaker normally closed contact QF1, a main circuit breaker normally open contact QF2, a main circuit breaker closing coil LC and a main circuit breaker opening coil LT;

[0039] The main circuit breaker anti-tripping circuit includes a closing circuit and an opening circuit;

[0040] The closing circuit and the opening circuit are both arranged between the positive and negative electrodes;

[0041] The closing circuit comprises: a closing button SB1, a main circuit breaker normally closed contact QF1, a main circuit breaker closing coil LC and a first relay connected in series in sequence;

[0042] The first relay comprises a first relay coil KT1 and a first normally closed contact K1';

[0043] The closing button SB1, the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1 are connected in series in sequence.

[0044] The first relay also includes a first normally open contact K1;

[0045] One end of the first normally open contact K1 is connected to the opening end of the normally closed contact QF1 of the main circuit breaker;

[0046] The other end of the first normally open contact K1 is connected to the tail end of the first relay coil KT1;

[0047] The first normally open contact K1 is connected in parallel with a series circuit formed by the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1.

[0048] The opening circuit comprises: an opening button SB2, a main circuit breaker normally open contact QF2, a main circuit breaker opening coil LT and a second relay which are connected in series in sequence.

[0049] The second relay comprises a second relay coil KT2 and a second normally closed contact K2';

[0050] The opening button SB2, the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker opening coil LT and the second relay coil KT2 are connected in series in sequence.

[0051] The second relay also includes a second normally open contact K2;

[0052] One end of the second normally open contact K2 is connected to the opening end of the normally open contact QF2 of the main circuit breaker;

[0053] The other end of the second normally open contact K2 is connected to the tail end of the second relay coil KT2;

[0054] The second normally open contact K2 is connected in parallel with a series circuit formed by the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker tripping coil LT and the second relay coil KT2.

[0055] The main circuit breaker closing coil LC controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2; the main circuit breaker opening coil LT controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2.

[0056] The first relay is a time-delay relay, and the time delay is 5-30 seconds, preferably 20 seconds.

[0057] The second relay is a time-delay relay, and the delay time is 5-30 seconds, preferably 20 seconds.

[0058] Working principle:

[0059] like Figure 1 As shown, the present application proposes a main circuit breaker anti-tripping circuit based on a time delay relay, specifically:

[0060] When closing, SB1 is closed, SB1, QF1, K1', LC, KT1 branches are energized, and after the main circuit breaker is closed, the state of the energized contacts of the main circuit breaker motor is reversed, QF1 is disconnected, and QF2 is closed. After the set time, K1 is closed and K1' is disconnected. When SB1 is stuck or short-circuited and the situation is not restored, if the equipment encounters a fault trip or is normally opened at this time, QF1 is closed and QF2 is disconnected. Since K1' is disconnected at this time, the closing coil LC loses power, and SB1 is connected to K1, avoiding reclosing due to SB1 adhesion.

[0061] When opening, SB2 is closed. Since QF1 is disconnected and QF2 is closed when closing, SB2, QF2, K2', LT, and KT2 branches are energized. After the main circuit breaker is opened, the state of the energized contacts of the main circuit breaker motor is reversed, QF2 is disconnected, and QF1 is closed. After the set time is reached, K2 is closed and K2' is disconnected. When SB2 is adhered, SB2 is connected to K2. If the main circuit breaker is closed at this time, the contact state is reversed, QF1 is disconnected, and QF2 is closed. Since K2' is disconnected, SB2 cannot supply power to the opening coil LT through the QF2, LT, and KT2 branches, and the main circuit breaker will not be opened after closing.

[0062] According to a second aspect of the present invention, a control method for a main circuit breaker anti-tripping circuit based on a time delay relay is provided. The method adopts the main circuit breaker anti-tripping circuit based on a time delay relay as described in any one of the first embodiments. The specific method is as follows:

[0063] When closing:

[0064] Press the closing button SB1, the closing circuit is energized, the main circuit breaker closing coil LC is energized, the main circuit breaker normally closed contact QF1 is disconnected, and the main circuit breaker normally open contact QF2 is closed. After the first relay reaches the preset time, the first relay coil KT1 is energized, and the first normally open contact K1 is closed, and the first normally closed contact K1' is disconnected;

[0065] When the closing button SB1 is stuck or short-circuited and has not been restored, if the equipment encounters a fault and the closing button SB1 trips or is normally opened, the main circuit breaker normally closed contact QF1 is closed and the main circuit breaker normally open contact QF2 is disconnected. Since the first normally closed contact K1' is disconnected at this time, the main circuit breaker closing coil LC loses power, and the closing button SB1 is connected to the first normally open contact K1 and is connected, avoiding the reclosing situation caused by the adhesion of the closing button SB1;

[0066] When opening:

[0067] When the opening button SB2 is pressed, the normally closed contact QF1 of the main circuit breaker is disconnected and the normally open contact QF2 of the main circuit breaker is closed. At this time, the opening circuit is energized, and the opening coil LT of the main circuit breaker is energized. At this time, the normally open contact QF2 of the main circuit breaker is disconnected and the normally closed contact QF1 of the main circuit breaker is closed. After the second relay reaches the set time, the coil KT2 of the second relay is energized. At this time, the second normally open contact K2 is closed and the second normally closed contact K2' is disconnected;

[0068] When the opening button SB2 is stuck, the opening button SB2 is connected to the second normally open contact K2 and the circuit is open; if the closing button SB1 is closed at this time, the main circuit breaker closing coil LC is energized, and the main circuit breaker normally closed contact QF1 is disconnected, and the main circuit breaker normally open contact QF2 is closed; since the second normally closed contact K2' is disconnected, the opening button SB2 cannot supply power to the main circuit breaker opening coil LT through the QF2, LT, and KT2 branches, and the main circuit breaker will not be closed and then opened.

[0069] In summary, the present invention provides a main circuit breaker anti-tripping circuit based on a time delay relay to solve the problem that the anti-tripping circuit in the prior art does not consider the sticking condition of the opening switch and the anti-tripping circuit has a complex structure:

[0070] 1) This application fully considers the sticking of the opening switch and the complex structure of the anti-tripping circuit. This application uses a power-on delay relay and a power-off delay relay to prevent the problem of closing and opening contact jumping caused by switch sticking during closing and opening, and has good engineering applicability;

[0071] 2) The present application utilizes the auxiliary contacts of the power-on delay relay and the power-off delay relay. When the closing and opening switches are sticking, the current passes through the auxiliary contact circuit instead of passing through the closing and opening switch branches, thereby avoiding the jumping of the closing and opening contacts and realizing protection of the main circuit breaker.

[0072] The present application fully considers the sticking of the closing and opening switches and the various fault conditions of disconnection due to faults during closing, and solves the main circuit breaker tripping under various fault conditions.

[0073] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A main circuit breaker anti-tripping circuit based on a time delay relay, characterized in that: include: Closing button SB1, opening button SB2, first relay, second relay, main circuit breaker normally closed contact QF1, main circuit breaker normally open contact QF2, main circuit breaker closing coil LC and main circuit breaker opening coil LT; The main circuit breaker anti-tripping circuit includes a closing circuit and an opening circuit; The closing circuit and the opening circuit are both arranged between the positive and negative electrodes; The closing circuit comprises: a closing button SB1, a main circuit breaker normally closed contact QF1, a main circuit breaker closing coil LC and a first relay connected in series in sequence; The opening circuit comprises: an opening button SB2, a main circuit breaker normally open contact QF2, a main circuit breaker opening coil LT and a second relay which are connected in series in sequence.

2. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 1 is characterized in that: The first relay comprises a first relay coil KT1 and a first normally closed contact K1'; The closing button SB1, the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1 are connected in series in sequence.

3. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 2 is characterized in that: The first relay also includes a first normally open contact K1; One end of the first normally open contact K1 is connected to the opening end of the normally closed contact QF1 of the main circuit breaker; The other end of the first normally open contact K1 is connected to the tail end of the first relay coil KT1; The first normally open contact K1 is connected in parallel with a series circuit formed by the main circuit breaker normally closed contact QF1, the first normally closed contact K1', the main circuit breaker closing coil LC and the first relay coil KT1.

4. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 3 is characterized in that: The second relay comprises a second relay coil KT2 and a second normally closed contact K2'; The opening button SB2, the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker opening coil LT and the second relay coil KT2 are connected in series in sequence.

5. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 4 is characterized in that: The second relay also includes a second normally open contact K2; One end of the second normally open contact K2 is connected to the opening end of the normally open contact QF2 of the main circuit breaker; The other end of the second normally open contact K2 is connected to the tail end of the second relay coil KT2; The second normally open contact K2 is connected in parallel with a series circuit formed by the main circuit breaker normally open contact QF2, the second normally closed contact K2', the main circuit breaker tripping coil LT and the second relay coil KT2.

6. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 5 is characterized in that: The first relay is a time-delay relay, and the time-delay time is 5-30 seconds.

7. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 6 is characterized in that: The second relay is a time-delay relay, and the delay time is 5-30 seconds.

8. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 5, characterized in that: The main circuit breaker closing coil LC controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2.

9. The main circuit breaker anti-tripping circuit based on the time delay relay according to claim 6, characterized in that: The main circuit breaker tripping coil LT controls the opening and closing of the main circuit breaker normally closed contact QF1 and the main circuit breaker normally open contact QF2.

10. A control method for a main circuit breaker anti-tripping circuit based on a time delay relay, characterized in that: Using the main circuit breaker anti-tripping circuit based on the time delay relay according to any one of claims 6 to 9, the control method includes: When closing: Press the closing button SB1, the closing circuit is energized, the main circuit breaker closing coil LC is energized, the main circuit breaker normally closed contact QF1 is disconnected, and the main circuit breaker normally open contact QF2 is closed. After the first relay reaches the preset time, the first relay coil KT1 is energized, and the first normally open contact K1 is closed, and the first normally closed contact K1' is disconnected; When the closing button SB1 is stuck or short-circuited and has not been restored, if the equipment encounters a fault and the closing button SB1 trips or is normally opened, the main circuit breaker normally closed contact QF1 is closed and the main circuit breaker normally open contact QF2 is disconnected. Since the first normally closed contact K1' is disconnected at this time, the main circuit breaker closing coil LC loses power, and the closing button SB1 is connected to the first normally open contact K1 and is connected, avoiding the reclosing situation caused by the adhesion of the closing button SB1; When opening: When the opening button SB2 is pressed, the normally closed contact QF1 of the main circuit breaker is disconnected and the normally open contact QF2 of the main circuit breaker is closed. At this time, the opening circuit is energized, and the opening coil LT of the main circuit breaker is energized. At this time, the normally open contact QF2 of the main circuit breaker is disconnected and the normally closed contact QF1 of the main circuit breaker is closed. After the second relay reaches the set time, the coil KT2 of the second relay is energized. At this time, the second normally open contact K2 is closed and the second normally closed contact K2' is disconnected; When the opening button SB2 is stuck, the opening button SB2 is connected to the second normally open contact K2 and a circuit is opened.

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