CN203720293U - Device used for monitoring DC insulation bus interaction - Google Patents

Abstract

The utility model discloses a device for monitoring the mutual channeling of DC insulated busbars. The device comprises two independently operated DC busbars respectively equipped with two separate DC grounding insulation monitoring devices; Two DC grounding insulation monitoring devices respectively input the balance bridge resistance of the other party to monitor the grounding resistance value of the other party; a set of communication lines are set between the two DC grounding insulation monitoring devices running separately for data communication; two DC grounding insulation monitoring devices The monitoring device respectively receives and acquires relevant measurement data through the communication line receiving and acquisition module; according to the measurement data, it is determined whether the DC crossover corresponding to the DC bus crossover occurs, and the utility model can accurately monitor whether the DC crossover occurs, and the occurrence of DC The DC line that crosses each other will give an alarm, and accurately find the circuit where the two DC busses cross each other.

Description

A device for monitoring cross-channeling of DC insulating busbars

technical field

The utility model relates to the technical field of electric power system insulation monitoring, and more specifically relates to a method and a device for monitoring the mutual channeling of DC insulating busbars.

Background technique

In the power system, in order to ensure the safe operation of the DC power supply for the substation, two independent DC power supplies are often provided, and the two DC sections of the same substation are required to operate independently. During operation, due to wiring errors or equipment aging, two sections of busbars are usually electrically connected, that is, the phenomenon of two sections of busbars holding hands.

The existing DC system is prone to electrical connection, that is, two-point grounding phenomenon. The two-point grounding phenomenon often causes certain dangers to the normal operation of relay protection in substations. Therefore, using a multimeter to monitor whether the two sections of the busbars are connected to each other can not accurately monitor whether the DC busbars are connected to each other, nor can it provide accurate alarms, and it is impossible to accurately find the circuit where the two sections of the DC busbars are connected to each other.

Therefore, the present invention provides a device for monitoring the mutual channeling of DC insulated busbars, which can accurately monitor whether DC channeling occurs, give an alarm to the DC line where DC channeling occurs, and accurately find the circuit where two sections of DC busbars have channeling together , is a problem to be solved urgently by those skilled in the art.

Utility model content

In view of this, the utility model provides a device for monitoring the cross-channeling of DC insulated busbars. Since a multimeter is used for monitoring in the prior art, it is impossible to accurately monitor whether DC cross-channeling occurs, and an alarm is given to the DC line where DC-insulated bus-bars have occurred. And accurately find the problem of the circuit where the two sections of DC buses cross each other.

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

A device for monitoring cross-channeling of DC insulation busbars, comprising:

Two DC grounding insulation monitoring devices respectively arranged on two independently operated DC busbars, and the two DC grounding insulation monitoring devices are connected by communication lines for data communication;

Two sets of balance bridge resistors set between the positive and negative terminals of the DC bus;

An acquisition module that is connected to the DC ground insulation monitoring device through a communication line and receives and acquires relevant measurement data.

Wherein, the communication line is an RS584 communication line.

It can be seen from the above-mentioned technical solutions that, compared with the prior art, the utility model discloses a device for monitoring the cross-channeling of DC insulating buses. Monitoring device: Wiring according to the way that DC bus crossing occurs, two DC grounding insulation monitoring devices input the balance bridge resistance of each other respectively, and monitor each other's grounding resistance resistance; between the two DC grounding insulation monitoring devices operating separately Set up a set of communication lines for data communication; two DC grounding insulation monitoring devices respectively receive and acquire relevant measurement data through the communication lines; determine whether DC crossover corresponding to the way of DC bus crossover occurs according to the measurement data, through this The invention can accurately monitor whether the DC crossover occurs, give an alarm to the DC line where the DC crossover occurs, and accurately search the circuit where the two DC busbars cross each other.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description It is only an embodiment of the utility model, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is a schematic structural diagram of a device for monitoring the mutual channeling of DC insulated buses disclosed in an embodiment of the present invention;

Fig. 2 is a wiring diagram of mutual channeling between the negative terminal of the first section of the busbar and the negative terminal of the second section of the busbar disclosed by the embodiment of the present invention;

Fig. 3 is a wiring diagram in which the positive end of the first section of the busbar and the positive end of the second section of the busbar disclose each other;

Fig. 4 is a wiring diagram in which the positive terminal of the first section of the busbar and the positive terminal of the second section of the busbar, and the negative terminal of the first section of the busbar and the negative terminal of the second section of the busbar are simultaneously interchanging;

Fig. 5 is a wiring diagram in which the negative terminal of the first section of the busbar and the positive terminal of the second section of the busbar are intersected according to the embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

The utility model discloses a device for monitoring the mutual channeling of DC insulated busbars. The device comprises two independently operated DC busbars respectively equipped with two separate DC grounding insulation monitoring devices; Two DC grounding insulation monitoring devices respectively input the balance bridge resistance of the other party to monitor the grounding resistance value of the other party; a set of communication lines are set between the two DC grounding insulation monitoring devices running separately for data communication; two DC grounding insulation monitoring devices The monitoring device receives and acquires relevant measurement data through the communication line receiving and acquisition module respectively; according to the measurement data, it is determined whether DC crossover corresponding to the way of DC bus crossover occurs, and whether DC crossover occurs can be accurately monitored through the present invention, and the occurrence of DC crossover is determined. Alarm for the channeling DC line, and accurately find the circuit where the two DC bus bars are channeling each other.

Please refer to accompanying drawing 1, which is a structural schematic diagram of a device for monitoring cross-channeling of DC insulating busbars disclosed in an embodiment of the present invention. The embodiment of the present invention discloses a device for monitoring the mutual channeling of DC insulating buses. Specifically, the device includes: two DC grounding insulation monitoring devices 101 and 102 respectively arranged on two independently operating DC buses. The ground insulation monitoring devices are connected through communication lines 103, and data communication is carried out; two sets of balance bridge resistors 104 are arranged between the positive and negative ends of the DC bus; and the DC ground insulation monitoring devices 101 and 102 are connected through communication lines 103 is connected to the collection module 105 that receives and collects the acquired relevant measurement data.

Preferably, the communication line mentioned above is an RS584 communication line.

Specifically, please refer to accompanying drawing 3, which is a wiring diagram of the mutual crossing between the negative terminal of the first busbar and the negative terminal of the second busbar disclosed by the embodiment of the present invention. As shown in Figure 3, the two independently operating DC busbars are equipped with two DC grounding monitoring devices respectively. Call the police. It usually happens when the two independently operated DC circuits have mutual channeling, and the two insulation monitoring devices 1 and 2 input the balanced resistance bridges of the other side to monitor the grounding resistance resistance of each other. In addition, there is a set of RS584 communication interfaces between the two DC monitoring devices running separately, and this set of communication interfaces also applies the multi-extension system of the master-slave structure.

From the above, as shown in Figure 2, when the independent DC power supplies have DC cross-channeling, that is, A and B in the figure are connected, the insulation detection of the insulation monitoring device 1 is that the negative bus 60k is grounded, and the insulation monitoring device 2 is insulated It is detected that the negative busbar 60k is grounded, and the two parties communicate through RS485. When the two instruments receive the relevant measurement data of the other party, they accurately measure and determine the DC mutual channeling. Both sides start the branch circuit inspection at the same time, the insulation detection device 1 will check that the branch 1 is 60k grounded, and the insulation detection device 2 will also check that the branch 1 is 60k resistance grounded, then it will be identified as the negative pole of the two branches Mutual channeling. Wherein, it needs to be explained that branch 1 may be any circuit, here only circuit 1 as shown in the figure should be any circuit.

Specifically, please refer to accompanying drawing 3, which is a wiring diagram of the positive end of the first section of the busbar and the positive end of the second section of the busbar disclosed by the embodiment of the present invention. As shown in Figure 3, when the independent DC power supplies have DC cross-channeling, that is, A and B in the figure are connected, the insulation detection of the insulation monitoring device 1 is that the positive bus 60k is grounded, and the insulation detection of the insulation monitoring device 2 is that the positive bus 60k Grounding, the two parties communicate through RS485, and when the two instruments receive the relevant measurement data of the other party, they will accurately measure and determine the DC crossover. Both parties start the branch circuit inspection at the same time, and the insulation detection device 1 will inquire that the branch circuit 1 is 60k grounded, and the insulation detection device 2 will also check that the branch circuit 1 is 60k grounded. We believe that the negative poles of these two branches are channeling each other. Among them, what needs to be explained is: branch 1 may be any circuit, we just follow the circuit 1 shown in the figure, it should be any circuit.

Specifically, please refer to accompanying drawing 4, which is a wiring diagram in which the positive terminal of the first section of the busbar and the positive terminal of the second section of the busbar, and the negative terminal of the first section of the busbar and the negative terminal of the second section of the busbar are simultaneously interchanging according to the embodiment of the present invention. As shown in Figure 4, the phenomenon that the positive and negative poles of two sections of busbars are connected to each other at the same time means that two sections of busbars have two insulation monitoring devices on one section of busbar. The two grounding points will interfere with each other, and there is usually no voltage difference between the two instruments, and the respective ground voltages of the two busbars are exactly the same. When the bus voltage of the two sections of the bus is not the same, the voltage difference phenomenon will occur.

When the independent DC power supplies have DC cross-channeling, that is, A and C in the figure are connected, and B and D are connected, the insulation detection of the insulation monitoring device 1 is that the positive busbar 60k is grounded, and the negative busbar is also a negative grounding resistance of 60k, and the insulation monitoring The insulation detection of device 2 is positive busbar 60k grounding, and the negative busbar is also negative grounding resistance 60k. The two parties communicate through RS485, and the two instruments receive the relevant measurement data from each other and exchange them. The two instruments can then accurately measure and judge DC mutual channeling. Both sides start the branch circuit inspection at the same time, the insulation detection device 1 will inquire that the branch circuit 1 is 30k grounded, and the insulation detection device 2 will also check that the branch circuit 1 is 30k grounded. We believe that the negative poles of the two branches are crossing each other. At this time, it is the resistance value of the two resistors connected in parallel to the ground. At this time, the resistance to the ground is not 60K. Among them, what needs to be said is: branch 1 may be any circuit, we just follow the circuit 1 shown in the figure, it should be any circuit.

Specifically, please refer to accompanying drawing 5, which is a wiring diagram of the mutual crossing of the negative terminal of the first section of the busbar and the positive terminal of the second section of the busbar disclosed by the embodiment of the present invention. As shown in Figure 5, we only list two phenomena for this phenomenon: Phenomenon 4: The negative terminal of the first busbar and the positive terminal of the second busbar appear to cross each other in two independent DC systems. Phenomenon 5: The positive terminal of the first section of the busbar and the negative terminal of the second section of the busbar appear to cross each other in the two-section DC system that operates independently. We combine these two into Phenomenon 4 to illustrate. The two independently operated DC busbars have different polarities. This phenomenon is rare, and when it occurs in the same branch circuit, a large current will appear in the two branch circuits. Posing the greatest danger, its excessive current usually causes the tripping of the protective circuit breaker. So we only make an explanation for the cross-channeling that occurs with different polarities. Take the negative terminal of the first busbar and the positive terminal of the second busbar as an example.

As shown in Figure 5, when the independent DC power supplies have DC cross-channeling, that is, B and C in the figure are connected, or A and D are connected, the insulation detection of the insulation monitoring device 1 is that the negative bus 60k resistance is grounded, and the insulation monitoring device 2. Insulation detection is the 60k resistance grounding of the positive busbar. The two parties communicate through RS485. The two instruments receive the relevant measurement data from each other and exchange them. The two instruments can also accurately measure and determine the DC crossover. Both parties start the branch circuit inspection at the same time, and the insulation detection device 1 will inquire that the branch circuit 1 is 60k grounded, and the insulation detection device 2 will also check that the branch circuit 1 is 60k grounded. We believe that the different polarities of the two branches are channeling each other, and the resistance to ground is 60K at this time. Among them, what needs to be explained is: branch 1 may be any circuit, we just follow the circuit 1 shown in the figure, it should be any circuit.

To sum up: the present invention discloses a method and device for monitoring the mutual channeling of DC insulated buses. The two DC grounding insulation monitoring devices respectively input the balance bridge resistance of each other to monitor each other's grounding resistance resistance; a set of communication lines is set between the two DC grounding insulation monitoring devices running separately to carry out data Communication; two DC grounding insulation monitoring devices respectively receive and acquire relevant measurement data through the communication line receiving and acquisition module; determine whether DC cross-channeling corresponding to the DC bus cross-channeling occurs according to the measurement data, and whether DC cross-channeling occurs can be accurately monitored through the present invention Mutual crossing, alarm the DC line where the DC crossing occurs, and accurately find the circuit where the two DC busses cross each other.

The above description of the disclosed embodiments enables those skilled in the art to realize or use the utility model. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims (2)

1. A device for monitoring the mutual channeling of DC insulation buses, characterized in that it comprises: Two DC grounding insulation monitoring devices respectively arranged on two independently operated DC busbars, and the two DC grounding insulation monitoring devices are connected by communication lines for data communication; Two sets of balance bridge resistors set between the positive and negative terminals of the DC bus; An acquisition module that is connected to the DC ground insulation monitoring device through a communication line and receives and acquires relevant measurement data. 2. The device according to claim 1, wherein the communication line is an RS584 communication line.