CN202009236U - Single-bus segmental running control device of substation - Google Patents

Abstract

The utility model discloses a segmental operation control device for a single busbar in a substation, which includes a control device for a bus coupling cabinet, a control device for a No. 1 power supply incoming cabinet, and a control device for a No. 2 power incoming cabinet. The DL1 normally closed contact (1) of the No. 1 power incoming circuit breaker and the DL2 normally closed contact (2) of the No. 2 power incoming circuit breaker are connected in parallel to the closing circuit of the bus tie circuit breaker DL3. The brake button (3) is connected in series with the brake coil (4); the closing circuit is connected with a switch (5) in series, and the switch (5) has two positions, and the first position is the normal position corresponding to the two circuit breakers. After the closed contacts are connected in parallel, they are connected in series to the closing circuit of the third circuit breaker; the second position is to connect the corresponding normally closed contacts of the two circuit breakers in parallel and then short circuit, and the closing circuit of the third circuit breaker is connected to the control power supply. The utility model can ensure the safety of the switching operation of the power supply, and is flexible in operation, and is suitable for the entire middle and low voltage system with a single bus section.

Description

Substation single bus segment operation control device

technical field

The utility model relates to a medium and low voltage power supply system, in particular to a substation operation control device for a single bus bar in a substation.

Background technique

With the continuous development of industrial enterprises, higher requirements are put forward for the reliability and safety of the power supply and distribution system of the factory. At present, the medium and low voltage power supply system adopts the substation with single busbar segmental operation mode, as shown in Figure 1. The three circuit breakers are No. 1 power incoming circuit breaker DL1, No. 2 power incoming circuit breaker DL2, and bus tie circuit breaker DL3. There are two main ways to switch incoming lines and bus tie cabinets:

The first is the operation mode in which the three circuit breakers of the incoming line and the bus tie cabinet can be closed at the same time without interlocking: For example, Chinese patent 200410067201 discloses a method for introducing a second power line into a high-voltage line for uninterrupted switching. It can realize uninterrupted switching of two power sources. If the incoming line I needs power outage maintenance, first confirm that the incoming line transformer meets the basic conditions for parallel operation, and then carry out phase verification work on the power supplies on both sides of the bus tie circuit breaker DL3. After the voltage difference, frequency difference, and phase difference between Ⅰ and incoming line Ⅱ meet the parallel conditions, close the bus tie circuit breaker DL3, and separate the circuit breaker DL1 of the incoming line Ⅰ after the operation is normal, and the load equipment downstream of the incoming line Ⅰ section will continue to supply power , Realize the uninterrupted switching of the two power supplies. However, this control method brings great hidden dangers to the safety of the long-term operation of the substation. Once the operation and maintenance personnel fail to check the power phase and close the bus tie circuit breaker DL3 by mistake, it will cause an asynchronous closing accident in the medium and high voltage power supply system. , It may cause a power trip in the substation area, or cause casualties, equipment damage, and large-scale power outages in the factory, affecting production.

The second is that the incoming bus-tie circuit breaker has a 3-in-2 interlocking control method: in order to ensure the safety of the power supply system, the commonly used substation incoming bus-tie circuit breaker has a 3-in-2 interlocking function. Control mode, that is, only two circuit breakers DL1, DL2, and DL3 are in the closed operating state at the same time; see Figure 2, taking the control device of the bus-connector cabinet as an example, the No. The normally closed contact corresponding to circuit breaker DL2 is connected in parallel to the closing circuit of bus tie circuit breaker DL3. When the incoming circuit breaker DL2 is in the closing working position, their corresponding normally closed contacts are opened, the closing circuit of the bus tie circuit breaker DL3 cannot be conducted, and the bus tie circuit breaker DL3 cannot perform the closing operation. The structure and electrical connection method of the No. 1 power incoming cabinet control device and the No. 2 power incoming cabinet control device are the same as the bus tie cabinet control device, and the closing circuit principle of circuit breaker DL1 and circuit breaker DL2 is also the same. In this way, it is avoided that the operation and maintenance personnel mistakenly close the third circuit breaker when the two circuit breakers are running, resulting in an asynchronous closing accident of the two power supplies paralleling each other, which improves the safety of the power supply system. However, in this electrical interlocking control mode, when there is a section of the incoming line that needs to be overhauled, due to the existence of the 3-in-2 interlocking function, the bus tie circuit breaker DL3 must first be disconnected before the bus tie circuit breaker DL3 is closed. As a result, the power supply of the load equipment downstream of the power supply that needs to be repaired is interrupted, and the uninterrupted switching of the power supply cannot be realized, which brings difficulties to arrange maintenance in important production areas of the factory.

Contents of the invention

The purpose of this utility model is to provide a substation single-bus section operation control device, which can ensure the safety of power supply switching operation, has no influence on the safe operation of the power supply system, and is flexible in operation. segmented system.

In order to achieve the above object, the utility model adopts the following technical solutions:

A control device for segmental operation of a single busbar in a substation, including a control device for a bus-connection cabinet, a control device for a No. 1 power incoming cabinet, and a control device for a No. 2 power incoming cabinet. The normally closed contact corresponding to the circuit breaker is connected in parallel to the closing circuit of the third circuit breaker;

For the bus tie cabinet control device, the DL1 normally closed contact of No. 1 power incoming circuit breaker and the DL2 normally closed contact of No. 2 power incoming circuit breaker are connected in parallel to the closing circuit of bus tie circuit breaker DL3, and the closing circuit is routed The closing button is connected in series with the gate coil; the structure and electrical connection method of the No. 1 power incoming cabinet control device and the No. 2 power incoming cabinet control device are the same as the bus coupling cabinet control device;

A changeover switch is connected in series in the closing circuit, and the changeover switch has two positions, the first position is to connect the normally closed contacts corresponding to the two circuit breakers in parallel and connect the closing contacts of the third circuit breaker in series. The gate circuit; the second position is to short-circuit the normally closed contacts corresponding to the two circuit breakers in parallel, so that the closing circuit of the third circuit breaker is directly connected to the control power supply.

The changeover switch is connected between the parallel connection of normally closed contacts corresponding to the two circuit breakers and the closing circuit.

The beneficial effects of the utility model are:

1. The utility model retains the 3-in-2 interlocking function of the circuit breaker, and this function is used in daily operation to eliminate the possibility of misalignment of power supplies and ensure the safe operation of the power supply and distribution system.

2. When the power supply system is overhauled, the 3-in-2 interlock function is temporarily switched off through the transfer switch and the power supplies are arranged side by side, which can meet the uninterrupted power supply of electrical equipment, which is of great significance to equipment maintenance and industrial production.

The utility model can ensure the safety of power supply switching operation, has no influence on the safe operation of the power supply system, and is flexible in operation. Defects have improved the operation and management level of the substation.

Description of drawings

Figure 1 is a schematic diagram of the existing single bus section operation mode

Figure 2 is the electrical schematic diagram of the existing bus coupler control device;

Fig. 3 is the electrical principle diagram of the control device of the bus coupler cabinet of the present invention.

In the figure: 1 circuit breaker DL1 normally closed contact, 2 circuit breaker DL2 normally closed contact, 3 circuit breaker DL3 closing button, 4 circuit breaker DL3 closing coil, 5 switchover switch.

Detailed ways

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

Referring to Fig. 3, a control device for segmental operation of a single busbar in a substation, including a control device for bus-connection cabinets, a control device for No. 1 power incoming cabinet, and a control device for No. 2 power incoming cabinets. Both include the normally closed contacts corresponding to the two circuit breakers and are connected in parallel to the closing circuit of the third circuit breaker; a switch 5 is connected in series in the closing circuit, and the switch 5 is connected to the normally closed contacts corresponding to the two circuit breakers. After the closed contacts are connected in parallel and the closing circuit; the switch 5 has two positions, the first position is to connect the normally closed contacts corresponding to the two circuit breakers in parallel and then connect the closing circuit of the third circuit breaker in series. circuit; the second position is to short-circuit the normally closed contacts corresponding to the two circuit breakers in parallel, so that the closing circuit of the third circuit breaker is directly connected to the control power supply.

For example: for the control device of the bus tie cabinet, the normally closed contact 1 of the No. 1 power incoming circuit breaker DL1 and the normally closed contact 2 corresponding to the No. 2 power incoming circuit breaker DL2 are connected in parallel and then connected in series to the switch 5, and the switch 5 In the closing circuit of the bus tie circuit breaker DL3 connected at the other end, the closing circuit is composed of the closing button 3 of the bus tie circuit breaker DL3 connected in series with the closing coil 4 . The diverter switch 5 has two positions. The first position is to connect the normally closed contacts 1 and 2 corresponding to the two circuit breakers DL1 and DL2 in parallel and then turn on the closing circuit of the bus tie circuit breaker DL3 in series. During the daily operation of the substation, the 3-in-2 interlock function can be used to eliminate the hidden danger of the power supply of the substation being mistakenly arranged side by side. The second position is to short-circuit the normally closed contacts 1 and 2 corresponding to the two circuit breakers DL1 and DL2 in parallel, and the closing circuit of the third circuit breaker is directly connected to the control power supply 220V. Release the 3-in-2 interlock function to complete the side-by-side operation, so as to ensure the uninterrupted power supply of the load equipment.

The structure and electrical connection method of the No. 1 power incoming cabinet control device and No. 2 power incoming cabinet control device are the same as the bus tie cabinet control device; the closing circuit principle of circuit breaker DL1 and circuit breaker DL2 is also the same.

After the installation of the utility model substation single bus segmental operation control device is completed, the control function needs to be checked. Take the substation (35kV/10kV) bus coupler cabinet as an example to illustrate, that is, the No. 1 power supply line is broken DL1 and No. 2 power incoming circuit breaker DL2 are in the working position, and bus tie circuit breaker DL3 is used. The verification steps are as follows:

1) The 35kV system first runs in parallel, and the 35kV/10kV transformer meets the conditions for parallel operation;

2) After the 35kV systems are paralleled, check the phase on the 10kV system side, and after confirming that the parallel conditions are met, turn the control switch of the bus coupler cabinet to the second position;

3) Press the close button of the bus tie cabinet, the bus tie circuit breaker DL3 is closed, and confirm that the voltmeter and ammeter on the panel of the bus tie cabinet have indications;

4) Open the bus tie circuit breaker DL3;

5) Turn the transfer switch of the bus tie cabinet to the first position, press the closing button of the bus tie cabinet again, the bus tie circuit breaker DL3 cannot be closed, and the 3-in-2 interlock function is valid;

6) The above verification proves that the switching mode of the bus coupler cabinet has been transformed successfully, and the 35kV system will be unmerged and restored to the original operation mode. After that, carry out the functional verification of the control device of No. 1 power incoming cabinet and the control device of No. 2 power incoming cabinet, and the method is the same as that of the bus coupling cabinet.

The above are only preferred embodiments of the present utility model, and are not used to limit the scope of protection of the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be Included within the protection scope of the present utility model.

Claims (2)

1. A substation single bus segmental operation control device, comprising a bus coupling cabinet control device, No. 1 power supply incoming cabinet control device and No. 2 power supply incoming cabinet control device, and the control devices of the three cabinets all include The normally closed contacts corresponding to the two circuit breakers are connected in parallel to the closing circuit of the third circuit breaker; For the bus tie cabinet control device, the No. 1 power incoming circuit breaker DL1 normally closed contact (1) and the No. 2 power incoming circuit breaker DL2 normally closed contact (2) are connected in parallel to the closing circuit of the bus tie circuit breaker DL3 Among them, the closing circuit is composed of a closing button (3) connected in series with a closing coil (4); The structure and electrical connection method of the No. 1 power incoming cabinet control device and the No. 2 power incoming cabinet control device are the same as those of the bus coupler cabinet control device; It is characterized in that: a switching switch (5) is connected in series in the closing circuit, and the switching switch (5) has two positions, the first position is to connect the normally closed contacts corresponding to the two circuit breakers in parallel to lead The closing circuit of the third circuit breaker is connected in series; the second position is to connect the normally closed contacts corresponding to the two circuit breakers in parallel and then short-circuit, so that the closing circuit of the third circuit breaker is directly connected to the control power supply. 2. The substation single-bus section operation control device according to claim 1, wherein the transfer switch (5) is connected between the parallel connection of normally closed contacts corresponding to two circuit breakers and the closing circuit.

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