CN221263454U - Main transformer low-voltage side circuit breaker circuit of 220kV transformer substation main transformer spraying system - Google Patents

Abstract

The utility model discloses a main transformer low-voltage side circuit breaker circuit of a 220kV transformer substation main transformer spraying system, which comprises a receiving module, a spraying system main machine and an intermediate relay, wherein the receiving module is connected with the main machine; the power supply anode of the receiving module is connected to the split position signal pin of the receiving module through the auxiliary node of the main transformer high-voltage side breaker, the auxiliary node of the main transformer medium-voltage side breaker and the node of the intermediate relay which are connected in series; the control coil of the intermediate relay is connected in series with the auxiliary node of the low-voltage side breaker of the main transformer and then is connected between the positive electrode and the negative electrode of the power supply of the receiving module. The utility model provides a main transformer low-voltage side circuit breaker circuit for a main transformer spraying system of a 220kV transformer substation; the utility model not only can completely and reliably realize the function of the main transformer spraying system of the 220kV transformer substation, but also has higher reliability and better safety.

Description

Main transformer low-voltage side circuit breaker circuit of 220kV transformer substation main transformer spraying system

Technical Field

The invention belongs to the field of electric automation, and particularly relates to a main transformer low-voltage side circuit breaker circuit of a main transformer spraying system of a 220kV transformer substation.

Background

Along with the development of economic technology and the improvement of living standard of people, electric energy becomes an indispensable secondary energy source in the production and living of people, and brings endless convenience to the production and living of people. Therefore, ensuring stable and reliable supply of electric energy becomes one of the most important tasks of the electric power system.

The main transformer of the 220kV transformer substation is a core component of the 220kV transformer substation. Therefore, the normal operation of the main transformer of the 220kV transformer substation is ensured, and the transformer is one of the core operation of a power system. The main transformer spraying system of the 220kV transformer substation is mainly a system for spraying a large amount of water mist to the main transformer body to cool the transformer under the condition that the main transformer is not electrified before the main transformer of the 220kV transformer substation is overheated or a fire disaster occurs.

The main transformer spraying system is started in a manual mode and an automatic mode. The external conditions required for starting the spraying system are as follows: 1. overheat signals of the temperature sensing wire of the transformer; 2. and the dividing signal of the main transformer three-side circuit breaker. The starting mode of the spraying system is divided into an automatic mode and a manual mode, and a main transformer temperature sensing line overheat signal is not needed in the manual mode. However, in either the manual mode or the automatic mode, the spraying system host needs to receive the position dividing signal of the three-side circuit breaker of the main transformer, so that the main transformer is ensured to be not electrified, and the spraying system can start the operation of spraying water to the main transformer body. Therefore, the split position signal of the main transformer three-side circuit breaker is crucial for the main transformer spraying system: the spraying system cannot be started due to the lack of the split position signal of the main transformer three-side circuit breaker.

At present, a main transformer low-voltage side circuit breaker circuit of a main transformer spraying system of a 220kV transformer substation adopts the scheme shown in fig. 1: the connection mode of the branch positions of the three-side circuit breakers of the main transformer used by the main transformer spraying system is generally that normally, normally closed nodes S1 (corresponding to high-voltage side normally closed nodes), S2 (corresponding to medium-voltage side normally closed nodes) and S3 (corresponding to low-voltage side normally closed nodes) of three auxiliary nodes of the circuit breakers of the main transformer are connected in series and are connected between the power supply positive electrode of the receiving module and branch position signal pins; the split position signal pin receives a split signal, provides the split signal for a receiving module of the main transformer spraying system and transmits the split signal to a spraying system host through the receiving module; the normally closed node is a node which is connected with the auxiliary node when the circuit breaker is in a split state. The circuit shown in fig. 1 is the most common solution.

Such a scheme as shown in fig. 1 is simple in circuit structure; however, this solution also brings a greater risk of operation, namely: when the low-voltage side bus of the 220kV transformer substation is subjected to power failure maintenance, the main transformer continues to operate. At this time, the normal operation of operating personnel is to break the main transformer low-voltage side breaker of the bus to be overhauled, pull the breaker trolley to the test position and pull out the corresponding aviation plug, realize the safety isolation of main transformer low-voltage side and overhauling the bus. Because the circuit breaker split signal of the low-voltage side of the main transformer is transmitted by the aviation plug, the split signal of the main transformer cannot be transmitted to the receiving module of the spraying system in the situation. This may result in a situation where the main transformer is not started up in the case where the main transformer is already not charged when the main transformer is in operation, if the main transformer is overloaded and the temperature exceeds the allowable set temperature to cause a fire, and the high-medium side circuit breaker is tripped at this time, thereby lengthening the period in which the main transformer is kept at a high temperature. This situation may greatly reduce the insulation performance of the internal structure of the main transformer, and such reduction of the insulation performance may not be recovered, thereby shortening the operation life of the main transformer and also reducing the reliability of the main transformer.

Disclosure of utility model

The utility model aims to provide a main transformer low-voltage side circuit breaker circuit of a 220kV transformer station main transformer spraying system, which is high in reliability and good in safety.

The main transformer low-voltage side circuit breaker circuit of the 220kV transformer substation main transformer spraying system comprises a receiving module, a spraying system main machine and an intermediate relay, wherein the receiving module is connected with the intermediate relay; the power supply anode of the receiving module is connected to the split position signal pin of the receiving module through the auxiliary node of the main transformer high-voltage side breaker, the auxiliary node of the main transformer medium-voltage side breaker and the node of the intermediate relay which are connected in series; the control coil of the intermediate relay is connected in series with the auxiliary node of the low-voltage side breaker of the main transformer and then is connected between the positive electrode and the negative electrode of the power supply of the receiving module.

And the auxiliary node of the main transformer high-voltage side breaker is a normally closed node.

And the auxiliary node of the main transformer medium-voltage side breaker is a normally closed node.

And the auxiliary node of the main transformer low-voltage side breaker is a normally open node.

The node of the intermediate relay is a normally closed node.

The type of the intermediate relay is JZX-22F (D).

The main transformer low-voltage side circuit breaker circuit of the main transformer spraying system of the 220kV transformer substation comprehensively considers the requirements and habits of 10kV bus overhaul of the current power system on the safety measure operation of the main transformer low-voltage side circuit breaker, and provides the main transformer low-voltage side circuit breaker circuit for the main transformer spraying system of the 220kV transformer substation; the utility model not only can completely and reliably realize the function of the main transformer spraying system of the 220kV transformer substation, but also has higher reliability and better safety.

Drawings

Fig. 1 is a schematic diagram of a main transformer low-voltage side circuit breaker of a main transformer spraying system of a conventional 220kV transformer substation.

Fig. 2 is a schematic diagram of functional modules of the present utility model.

Fig. 3 is a schematic diagram of a circuit state of a main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system when the circuit breaker is separated.

Fig. 4 is a schematic diagram of a circuit state of a main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system when the circuit breaker is in a closed position.

Detailed Description

Fig. 2 is a schematic diagram of functional modules of the present utility model: the utility model discloses a main transformer low-voltage side circuit breaker circuit of a main transformer spraying system of a 220kV transformer substation, which comprises a receiving module, a spraying system main machine and an intermediate relay, wherein the receiving module is connected with the main transformer low-voltage side circuit breaker circuit of the main transformer spraying system; the power supply anode of the receiving module is connected to the split position signal pin of the receiving module through the auxiliary node of the main transformer high-voltage side breaker, the auxiliary node of the main transformer medium-voltage side breaker and the node of the intermediate relay which are connected in series; the control coil of the intermediate relay is connected in series with the auxiliary node of the low-voltage side breaker of the main transformer and then is connected between the positive electrode and the negative electrode of the power supply of the receiving module.

In particular, a preferred embodiment is: the auxiliary node of the breaker at the high voltage side of the main transformer is a normally closed node; the auxiliary node of the main transformer medium-voltage side breaker is a normally closed node; the auxiliary node of the main transformer medium-voltage side breaker is a normally open node; the node of the intermediate relay is a normally closed node.

In specific implementation, the type of the intermediate relay is JZX-22F (D)

Fig. 3 is a schematic diagram of a circuit state of a main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system when the circuit breaker is separated: when the main transformer works normally, if abnormal conditions such as overhigh temperature occur, the main transformer low-voltage side circuit breaker is closed at the split position, the S1 and the S2 are closed, the connected node S3 is opened, the intermediate relay S4 does not act, and the normally closed node for providing the split position signal for the receiving module on the intermediate relay is closed, so that the receiving module can receive the split position signal of the circuit breaker, and the situation is consistent with the actual situation. At this time, the 220kV transformer substation main transformer spraying system can work normally.

Or in the maintenance state, the aviation plug of the breaker trolley is pulled out, and the trolley is in a test state (at the moment, the connection between the low-voltage side of the main transformer and the 10kV bus is disconnected, so that the main transformer is in a separated state and the separated position is illustrated in the application), and the node S3 is opened; at this time, if an abnormal condition such as an excessive temperature of the main transformer occurs, the main transformer low-voltage side circuit breaker is closed at the split position, the S1 and the S2, and the intermediate relay does not act in the maintenance state, and the normally closed node for providing the split position signal for the receiving module on the intermediate relay is also closed, so that the receiving module can receive the split position signal of the circuit breaker, which is consistent with the actual condition. Therefore, in the overhaul state, the circuit can enable the main transformer spraying system of the 220kV transformer substation to work normally.

Fig. 4 is a schematic diagram of a circuit state of a main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system when the circuit breaker is in a closed position: when the circuit breaker on the low-voltage side of the main transformer is in a closed position (no abnormal condition exists at the moment), the connected node S3 is closed, the intermediate relay acts, the normally closed node which provides the split position signal for the receiving module on the intermediate relay is opened, and the receiving module can not receive the split position signal of the circuit breaker, so that the circuit breaker is consistent with the actual situation.

Claims (6)

1. A main transformer low-voltage side circuit breaker circuit of a 220kV transformer substation main transformer spraying system comprises a receiving module and a spraying system main machine, and is characterized by further comprising an intermediate relay; the power supply anode of the receiving module is connected to the split position signal pin of the receiving module through the auxiliary node of the main transformer high-voltage side breaker, the auxiliary node of the main transformer medium-voltage side breaker and the node of the intermediate relay which are connected in series; the control coil of the intermediate relay is connected in series with the auxiliary node of the low-voltage side breaker of the main transformer and then is connected between the positive electrode and the negative electrode of the power supply of the receiving module.

2. The main transformer low-voltage side breaker circuit of the 220kV transformer substation main transformer spraying system according to claim 1, wherein the auxiliary node of the main transformer high-voltage side breaker is a normally closed node.

3. The main transformer low-voltage side breaker circuit of the 220kV transformer substation main transformer spraying system according to claim 2, wherein the auxiliary node of the main transformer medium-voltage side breaker is a normally closed node.

4. The main transformer low-voltage side breaker circuit of the 220kV transformer substation main transformer spraying system according to claim 3, wherein the auxiliary node of the main transformer medium-voltage side breaker is a normally open node.

5. The main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system according to claim 4, wherein the node of the intermediate relay is a normally closed node.

6. The main transformer low-voltage side circuit breaker of the 220kV transformer substation main transformer spraying system according to one of claims 1 to 5, wherein the type of the intermediate relay is JZX-22F (D).