CN205070616U - Supervision return circuit of trip(ping) circuit - Google Patents

Abstract

The monitoring circuit of the trip circuit of the utility model includes a DC control power supply, a circuit breaker, a first detection point BI1 and a second detection point BI2, and the circuit breaker includes a trip coil TQ, a normally open contact DL1 and a normally closed contact DL2; The normally closed contact DL2 is connected in series with the second detection point BI2 and then connected in parallel with the normally open contact DL1. The two ends of the above parallel circuit are respectively connected to the first end of the trip coil TQ and the first end of the first detection point BI1. The second terminal of the coil TQ is connected to the first pole of the DC control power supply, and the second terminal of the first detection point BI1 is connected to the second pole of the DC control power supply. Not only can it monitor the status of the tripping coil of the circuit breaker, but it can also monitor whether the control power supply disappears, whether there is any loose wire in the circuit, and whether there is a wrong connection in the circuit. The status of the circuit breaker trip coil and the loss of control power can be monitored at any time.

Description

Monitoring circuit for tripping circuit

technical field

The utility model relates to a monitoring circuit, in particular to a monitoring circuit of a tripping circuit.

Background technique

The control objects of the power system mainly include circuit breakers, isolating switches and other equipment. Among them, the circuit breaker is used to connect and control the important equipment of the power grid equipment and lines, and the reasonable, reliable and perfect circuit breaker operation circuit design can significantly improve the dynamic performance of the circuit breaker. correctness and reliability.

As shown in Figure 1, in the traditional protection device, the normally closed contact of the closing position relay HWJ is connected in series with a normally open contact of the circuit breaker to form the monitoring circuit of the trip circuit. When the circuit breaker is closed, the normally open contact DL is closed, if the trip coil TQ is intact, the relay HWJ starts, the normally closed contact of the relay HWJ opens, the circuit is blocked, and the trip circuit disconnection signal is not sent; if the trip coil TQ is disconnected, Then the relay HWJ does not start, the normally closed contact of the relay HWJ is closed, the circuit is connected, and the trip circuit disconnection signal is sent. In the traditional protection device, only the state of the trip coil TQ is monitored when the circuit breaker is in position, and the relay set in the protection device complicates the circuit and increases the difficulty of troubleshooting.

Utility model content

The technical problem to be solved by the utility model is to provide a monitoring circuit of the tripping circuit, which can monitor the state of the tripping coil of the circuit breaker and control whether the power supply disappears at any time.

The monitoring circuit of the tripping circuit adopted by the utility model to solve its technical problems includes a DC control power supply, a circuit breaker, a first detection point BI1 and a second detection point BI2, and the circuit breaker includes a tripping coil TQ, a normally open contact DL1 and Normally closed contact DL2; the normally closed contact DL2 is connected in parallel with the normally open contact DL1 after being connected in series with the second detection point BI2. One end, the second end of the trip coil TQ is connected to the first pole of the DC control power supply, and the second end of the first detection point BI1 is connected to the second pole of the DC control power supply.

Further, the second terminal of the trip coil TQ is connected to the negative pole L− of the DC control power supply, and the second terminal of the first detection point BI1 is connected to the positive pole L+ of the DC control power supply.

Further, an alarm device is connected at the positions of the first detection point BI1 and the second detection point BI2.

Further, the alarm signal of the alarm device is sent by an alarm lamp.

The beneficial effects of the utility model are: not only can monitor the state of the tripping coil of the circuit breaker, but also can monitor whether the control power supply disappears, whether there is any loose thread in the circuit, and whether there is any wrong connection in the circuit.

Description of drawings

Fig. 1 is a schematic diagram of a monitoring circuit of a traditional tripping circuit;

Fig. 2 is the schematic diagram of the monitoring circuit of the tripping circuit of the present invention;

Fig. 3 is a schematic diagram of the channel when the circuit breaker is in the divided state;

Fig. 4 is a schematic diagram of the channel when the circuit breaker is in the closed state;

detailed description

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

As shown in Figure 2, the monitoring circuit of the trip circuit of the present invention includes a DC control power supply, a circuit breaker, a first detection point BI1 and a second detection point BI2, and the circuit breaker includes a trip coil TQ, a normally open contact DL1 and Normally closed contact DL2; the normally closed contact DL2 is connected in parallel with the normally open contact DL1 after being connected in series with the second detection point BI2. One end, the second end of the trip coil TQ is connected to the first pole of the DC control power supply, and the second end of the first detection point BI1 is connected to the second pole of the DC control power supply.

As shown in Figure 2, the wire connecting the trip coil TQ with the normally open contact DL1 is L1, the wire connecting the first detection point BI1 with the normally open contact DL1 is L2, and the normally closed contact DL2 is connected with the second detection point BI2 The wire connected to the second detection point BI2 is L3, the wire connecting the second detection point BI2 to the wire L2 is L4, and the wire connecting the normally closed contact DL2 to the wire L1 is L5.

Wherein, when the second terminal of the trip coil TQ is connected with the positive pole L+ of the DC control power supply, the second terminal of the first detection point BI1 is connected with the negative pole L- of the DC control power supply; when the second terminal of the trip coil TQ is connected with the DC control power supply When the negative pole L- of the power supply is connected, the second terminal of the first detection point BI1 is connected with the positive pole L+ of the DC control power supply. In this embodiment, the second end of the trip coil TQ is connected to the negative pole L− of the DC control power supply, and the second end of the first detection point BI1 is connected to the positive pole L+ of the DC control power supply.

In order to directly reflect the current signals of the first detection point BI1 and the second detection point BI2 and facilitate on-site operation, as a preferred embodiment, an alarm device 2 is connected at the positions of the first detection point BI1 and the second detection point BI2. The alarm signal of the alarm device 2 can be sent by a voice control device such as a buzzer. In this embodiment, the alarm signal of the alarm device 2 is sent by a warning light.

When the circuit breaker is in position, the normally open contact DL1 is opened, and the normally closed contact DL2 is closed. The schematic diagram of the channel is shown in Figure 3. If the trip coil TQ is intact, the first detection point BI1 and the second detection point BI2 have current signals; if the trip coil TQ is disconnected, the first detection point BI1 and the second detection point BI2 have no current signal, and the alarm light is on. When the alarm light is on, it indicates that the trip circuit is disconnected. Remind the staff to check the tripping circuit to avoid the circuit breaker refusing to move when a fault occurs, thereby expanding the scope of the accident.

When the circuit breaker is in the closing position, the normally open contact DL1 is closed, and the normally closed contact DL2 is open, as shown in Figure 4. If the trip coil TQ is intact, there is a current signal at the first detection point BI1 and no current signal at the second detection point BI2; if the trip coil TQ is disconnected, there is no current signal at the first detection point BI1 and the second detection point BI2, The alarm light is on, and if the alarm light is on, it indicates that the trip circuit is disconnected. Remind the staff to check the tripping circuit to avoid the circuit breaker refusing to move when a fault occurs, thereby expanding the scope of the accident.

During routine maintenance and troubleshooting of the monitoring circuit of the tripping circuit of the present invention, corresponding maintenance can be done according to the states of BI1 and BI2 in the table below.

Among them, X: there is current signal, —: no current signal.

When there is no current signal at BI1 and BI2, the alarm light is on, reminding the staff to check the trip circuit, so as to avoid the circuit breaker refusing to move in case of a fault and expanding the scope of the accident. The staff checks according to the following steps:

1. Check whether the control power supply is out of power;

2. Check whether the tripping coil is disconnected;

3. Check whether DL1 and DL2 are connected incorrectly;

4. Check whether there is any loose thread and broken circuit.

Therefore, the monitoring circuit of the trip circuit of the utility model can not only monitor the state of the trip coil of the circuit breaker, but also monitor whether the control power supply disappears, whether there is a loose thread in the circuit, and whether there is a wrong connection in the circuit.

Claims (4)

1. The monitoring circuit of the trip circuit is characterized in that it includes a DC control power supply, a circuit breaker, a first detection point BI1 and a second detection point BI2, and the circuit breaker includes a trip coil TQ, a normally open contact DL1 and a normally closed contact DL2 ; The normally closed contact DL2 is connected in series with the second detection point BI2 and then connected in parallel with the normally open contact DL1, and the two ends of the parallel circuit are respectively connected to the first end of the trip coil TQ and the first end of the first detection point BI1. The second terminal of the trip coil TQ is connected to the first pole of the DC control power supply, and the second terminal of the first detection point BI1 is connected to the second pole of the DC control power supply. 2. The monitoring circuit of the trip circuit according to claim 1, characterized in that: the second end of the trip coil TQ is connected to the negative pole L- of the DC control power supply, and the second end of the first detection point BI1 is connected to The positive pole L+ of the DC control power supply is connected. 3. The monitoring circuit of the tripping circuit according to claim 1 or 2, characterized in that an alarm device (2) is connected at the positions of the first detection point BI1 and the second detection point BI2. 4. The monitoring circuit of the tripping circuit according to claim 3, characterized in that: the alarm signal of the alarm device (2) is sent by an alarm lamp.