CN110349782A - A kind of electrical five-defence block circuit - Google Patents

Abstract

The invention provides an electrical five-proof locking circuit, which includes a grounding knife locking circuit, a first isolating switch locking circuit on the bus side, a second isolating switch locking circuit, a third isolating switch locking circuit on the line side, and a temporary grounding knife locking circuit ;In the first isolating switch closing circuit and the second isolating switch closing circuit, the first isolating switch position contact is connected to the common node through the temporary grounding knife locking circuit, and the second isolating switch position contact is connected to the common node through the temporary grounding knife locking circuit. node connection. Wherein, the common node is the node where the position contact of the first isolating switch and the position contact of the second isolating switch are connected to the same place. When the temporary grounding knife is grounded, because the temporary grounding knife blocking circuit is connected or disconnected according to the bus voltage, it can adaptively solve the problem that due to the lack of effective blocking of the temporary grounding line, when debugging the isolating switch of the current bus bar, it is mistakenly connected to another live bus bar Technical problems of casualties and equipment damage caused by isolating switches.

Description

An electrical five-proof locking circuit

technical field

The invention relates to the technical field of electrical equipment maintenance, in particular to an electrical five-proof locking circuit.

Background technique

The safety of the power grid puts forward the requirements of "five preventions" for electrical equipment, which clearly stipulates that electrical equipment with a voltage level of 110kV and above should first adopt the design principle of electrical misoperation prevention interlocking. Therefore, it has become an effective and feasible means to prevent human misoperation and other accidents from setting up electrical lockout on the secondary circuit of the operation. The switching operation should be carried out in strict accordance with the prescribed power-off and transmission sequence, and it is strictly forbidden to close the switch with the ground wire.

As shown in Figure 1, there are isolation switches 1G and 2G on the bus side of a certain line interval. One end of the 1G isolation switch is connected to the first section of the bus 1M, and the other end is connected to the 2G isolation switch and then connected to the circuit breaker DL. The 2G isolation switch One end of the bus is connected to the second section of the bus 2M, and the other end is connected to the 1G disconnector; the 2G disconnector is connected to the 02G grounding blade and is an integrated structure, and there is a mechanical interlocking relationship between the 2G disconnecting switch and the 02G grounding blade, that is, when the 2G When the isolating switch is in the closing position, the 02G grounding knife mechanical interlocking circuit control cannot perform closing operation. On the other hand, when the 02G grounding knife is in the closing position, the 2G isolating switch mechanical interlocking circuit control cannot perform closing operation.

When the 2G isolating switch on the bus side in Figure 1 needs to be overhauled, first disconnect the bus coupler, that is, disconnect the bus coupler circuit breaker ML, disconnect its 1G isolating switch and 2G isolating switch, and then disconnect the second section of the bus 2M Power outage, exit operation with maintenance interval, that is, disconnect the circuit breaker DL, put the 1G isolating switch, 2G isolating switch, and 4G isolating switch in the disconnected position, and then put the 02G grounding knife and the grounding knife on the second busbar 2M IIGD1 are all closed, and both sides of the isolating switch with maintenance 2G are grounded to ensure the safety of the maintenance personnel.

When the 1G isolating switch on the bus side in Figure 1 needs to be overhauled, first disconnect the bus coupler, that is, disconnect the bus coupler circuit breaker ML, disconnect its 1G isolating switch and 2G isolating switch, and then disconnect the first section of the bus 1M Power outage, exit operation with maintenance interval, that is, disconnect the circuit breaker DL, put the 1G isolating switch, 2G isolating switch, and 4G isolating switch in the disconnected position, and then put the 02G grounding knife and the grounding knife on the first busbar 1M All IGD1s are closed, and both sides of the isolating switch 1G with maintenance are grounded to ensure the safety of the maintenance personnel.

However, since the isolating switch 1G and 2G need to check their closed and disconnected states during debugging during the maintenance process, when the switch needs to be closed, the 02G grounding knife needs to be separated. To protect the safety of personnel, it is necessary to add a temporary grounding wire as shown in L02G in Figure 2. L02G represents the temporary grounding knife, that is, the temporary grounding knife of L02G should be closed (in the closed position) at this time.

However, at present, the location of the temporary grounding knife is not connected to the on-site electrical five-proof locking circuit (as shown in Figure 3). Separated (in the sub-position), since the DL contact, 02G contact, 04G1 contact, and 2G contact are all in the sub-position, the 1G control circuit can be unlocked for use, and there may be misoperations that cause the 1G isolation switch to close. Since the bus 1M is charged, it will work at this time There are serious safety problems when the personnel are debugging the isolation switch 2G. They often need to be unlocked to debug the knife switch. The knife lock circuit has no way to meet the needs of self-adaptive maintenance and is only suitable for traditional switching operations.

Therefore, due to the lack of effective blocking of the temporary ground wire, when debugging the isolating switch of the current bus, the casualties and equipment damage caused by mis-closing the isolating switch of another live bus have become a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

The embodiment of the present invention provides an electrical five-prevention locking circuit, which is used to solve the casualties caused by wrongly closing the isolating switch of another live bus when debugging the isolating switch of the current bus due to the lack of effective locking of the temporary ground wire. The technical problem of equipment damage, and the need for self-adaptive maintenance of the closed loop can be achieved without any unlocking key.

In view of this, the present invention provides an electrical five-proof locking circuit, including the grounding knife locking circuit, the first isolating switch locking circuit on the bus side, the second isolating switch locking circuit, the third isolating switch locking circuit on the line side and temporary Grounding knife locking circuit;

In the first isolating switch closing circuit and the second isolating switch closing circuit, the position contact of the first isolating switch is connected to the common node through the temporary grounding knife locking circuit, and the position contact of the second isolating switch is connected to the common node through the A temporary grounding knife blocking loop is connected to the common node;

Wherein, the common node is the node where the first isolating switch dividing contact and the second isolating switch dividing contact are connected to the same place;

When the temporary grounding knife is grounded, the temporary grounding knife blocking circuit is connected or disconnected according to the bus voltage.

Preferably, the temporary grounding knife locking circuit between the second isolating switch position contact and the common node includes: a first closing contact of the temporary grounding knife and a first voltage contact;

The common node, the first closing contact of the temporary grounding knife, the first voltage contact and the second isolating switch dividing contact are sequentially connected;

Wherein, the first closing contact of the temporary grounding blade is connected or disconnected according to the grounding state of the temporary grounding blade. The first voltage contact is connected or disconnected according to the voltage of the first bus corresponding to the first isolation switch.

Preferably, the temporary grounding knife locking circuit between the first isolating switch position contact and the common node includes: a first closing contact of the temporary grounding knife and a first voltage contact;

The common node, the second closing contact of the temporary grounding knife, the second voltage contact and the first isolating switch dividing contact are sequentially connected;

Wherein, the second closing contact of the temporary grounding blade is connected or disconnected according to the grounding state of the temporary grounding blade. The second voltage contact is connected or disconnected according to the voltage of the second bus bar corresponding to the second isolating switch.

Preferably, the temporary grounding knife locking circuit between the second isolating switch divider contact and the common node further includes: a first divider contact of the temporary grounding knife;

The branch formed by the first closing contact of the temporary grounding blade and the first voltage contact is connected in parallel with the first dividing contact of the temporary grounding blade.

Preferably, the temporary grounding knife locking circuit between the first isolating switch divider contact and the common node further includes: a second divider contact of the temporary grounding knife;

The branch formed by the second closing contact of the temporary grounding blade and the second voltage contact is connected in parallel with the second dividing contact of the temporary grounding blade.

Preferably, each contact in the electrical five-proof locking circuit is from a relay contact.

Preferably, both the first voltage contact and the second voltage contact are from three-phase non-voltage relay contacts.

Preferably, the three-phase no-voltage relay detects the voltages of A630, B630, C630 and N600 on the bus.

Preferably, when the voltages among the A630, the B630, the C630 and the N600 are all lower than the settable low-voltage setting value 1, the three-phase no-voltage relay detects that the bus is no-voltage.

It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages:

The invention provides an electrical five-proof locking circuit, which includes a grounding knife locking circuit, a first isolating switch locking circuit on the bus side, a second isolating switch locking circuit, a third isolating switch locking circuit on the line side, and a temporary grounding knife locking circuit ; In the first isolating switch locking circuit and the second isolating switch locking circuit, the first isolating switch position contact is connected to the common node through the temporary grounding knife locking circuit, and the second isolating switch position contact is connected to the common node through the temporary grounding knife locking circuit. node connection. Wherein, the common node is the node where the position contact of the first isolating switch and the position contact of the second isolating switch are connected to the same place. When the temporary grounding knife is grounded, because the temporary grounding knife blocking circuit is connected or disconnected according to the bus voltage, it can solve the problem that due to the lack of effective locking of the temporary grounding wire, when debugging the isolating switch of the current bus, the isolating switch of another live bus is mistakenly closed The resulting technical problems of casualties and equipment damage can also meet the needs of the self-adaptive maintenance of the closed circuit and the temporary ground wire.

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 drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings on the premise of not paying creative efforts.

Figure 1 is a schematic diagram of the actual main wiring on site;

Figure 2 is a schematic diagram of the actual main wiring after the on-site temporary grounding wire is connected;

Fig. 3 is the structural representation of existing electrical five-prevention locking circuit;

Fig. 4 is a structural schematic diagram of an embodiment of an electrical five-prevention locking circuit provided by an embodiment of the present invention;

Fig. 5 is a structural schematic diagram of a temporary grounding knife blocking circuit between the second isolating switch position contact and the common node;

Fig. 6 is a structural schematic diagram of a temporary grounding knife blocking circuit between the first isolating switch position contact and the common node;

FIG. 7 is a schematic structural diagram of the first voltage contact.

Detailed ways

The embodiment of the present invention provides an electrical five-proof locking circuit, which is used for casualties and equipment caused by mistakenly closing the isolating switch of another live bus when debugging the isolating switch of the current bus due to the lack of effective locking of the temporary ground wire. For the technical problem of damage, abandon the original practice of relying on unlocking and debugging, and achieve self-adaptive locking loop.

In order to make the purpose, features and advantages of the present invention more obvious and understandable, 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 following The described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 4, an embodiment of an electrical five-proof blocking circuit provided by the present invention, including: temporary grounding knife blocking circuit b, temporary grounding knife blocking circuit c, grounding knife blocking circuit, and the first isolating switch on the bus side are locked loop, the second isolating switch locking loop and the third isolating switch locking loop on the line side.

It should be noted that each contact point in FIG. 4 corresponds to each isolating switch and grounding knife in FIG. 2 . The first isolating switch locking loop in the embodiment of the present invention includes: DL split contact, 02G split contact, 04G1 split contact, temporary grounding knife locking loop b, 2G split contact, 2G closing contact and 1G control loop. The second isolating switch locking circuit includes: DL split contact, 02G split contact, 04G1 split contact, temporary grounding knife locking circuit c, 1G split contact, 1G closing contact and 2G control loop. The third isolating switch locking loop includes: DL split contact, 02G split contact, 04G1 split contact, 04G2 split contact and a 4G control loop. And there are three grounding knife locking circuits: namely (1) the circuit composed of DL split contact, 1G split contact, 2G split contact, 4G split contact and 02G control loop; (2) DL split contact, 1G split contact The circuit composed of contacts, 2G position contacts, 4G position contacts and 04G1 control circuit; (3) The circuit composed of DK7 position contacts, YJS position contacts, 4G position contacts and 04G2 control circuit.

In the first isolating switch closing circuit and the second isolating switch closing circuit, the first isolating switch position contact (that is, 1G position contact) is connected to the common node a through the temporary grounding knife locking circuit c, and the second isolating switch position contact (that is, the 2G sub-point contact) is connected to the common node a through the temporary grounding knife blocking circuit b.

Wherein, the common node a is the node where the position contact of the first isolating switch and the position contact of the second isolating switch are connected to the same place.

When the temporary grounding knife is grounded, the temporary grounding knife blocking circuit b or c is connected or disconnected according to the bus voltage, which can solve the problem of mistakenly closing another live bus when debugging the isolating switch of the current bus due to the lack of effective locking of the temporary grounding Technical problems of casualties and equipment damage caused by isolating switches.

Further, as shown in Fig. 5, the temporary grounding knife blocking circuit b between the second isolating switch position contact and the common node a includes: the first closing contact k1 of the temporary grounding knife, the first voltage contact k2 and the temporary grounding Knife first subpoint contact k3.

The common node a, the first closing contact k1 of the temporary grounding knife, the first voltage contact k2 and the second dividing contact of the isolating switch are connected in sequence.

The first close contact k1 of the temporary grounding knife and the branch circuit formed by the first voltage contact k2 are connected in parallel with the first partial contact k3 of the temporary grounding knife.

Among them, the first closing contact k1 of the temporary grounding knife is connected or disconnected according to the grounding state of the temporary grounding knife, that is, when the temporary grounding knife L02G is grounded in Figure 2, the first closing contact k1 of the temporary grounding knife is connected, and it is disconnected if not grounded. open. The first voltage contact k2 is connected or disconnected according to the voltage of the first bus bar corresponding to the first isolating switch, that is, when the voltage of the bus bar 1M in Fig. When it is higher than the voltage setting value 2, it will be disconnected. It should be noted that the judging condition for whether the first sub-point contact k3 of the temporary grounding blade is on or off is opposite to that of the first closing contact k1 of the temporary grounding blade.

Furthermore, as shown in Figure 6, the temporary grounding knife blocking circuit c between the first isolating switch divider contact and the common node a includes: the second closing contact k4 of the temporary grounding knife, the first voltage contact k5 and the second Temporary grounding knife sub-point contact k6.

The common node a, the second closing contact k4 of the temporary grounding knife, the second voltage contact k5 and the first isolating switch dividing contact k6 are sequentially connected.

The branch formed by the second closing contact k4 of the temporary grounding knife and the second voltage contact k5 is connected in parallel with the second dividing contact k6 of the temporary grounding knife.

Among them, the second closing contact k4 of the temporary grounding knife is connected or disconnected according to the grounding state of the temporary grounding knife, that is, when the temporary grounding knife L02G is grounded in Figure 2, the second closing contact k4 of the temporary grounding knife is connected, and it is disconnected if it is not grounded. open. The second voltage contact k5 is connected or disconnected according to the voltage of the second bus bar corresponding to the second isolating switch, that is, when the voltage of the bus bar 2M in Fig. When it is higher than the voltage setting value 2, it will be disconnected. It should be noted that the judging condition of whether the temporary grounding knife second sub-position contact k6 is on or off is opposite to that of the temporary grounding knife second closing contact k4.

Furthermore, each contact in the electrical five-proof locking circuit provided by the embodiment of the present invention is from an auxiliary contact or a relay contact. In addition, both the first voltage contact k2 and the second voltage contact k5 are from three-phase non-voltage relay contacts. As shown in FIG. 7 (taking the first voltage contact k2 as an example), the three-phase non-voltage relay detects the voltage between A630, B630, C630 and N600 on the bus. When the voltage between A630, B630, C630 and N600 is less than the settable low-voltage setting value 1, the three-phase no-voltage relay detects that the bus is no voltage.

In this embodiment, it should be noted that the closing contact means that if the switch or grounding knife corresponding to the contact is in the closed state in Figure 2, the closing contact in Figure 4 is connected, and the dividing contact means If the switch or the grounding knife corresponding to the contact is in the disconnected state in Figure 2, the closing contact in Figure 4 is turned on.

The following will introduce the working process of a kind of electrical five-prevention locking circuit provided by the present invention:

In Fig. 2, after the temporary ground wire L02G needs to be installed after the maintenance of the isolating switch 2G, in order to operate the isolating switch 1G, due to the existence of the temporary grounding knife locking circuit b of the electrical five-proof locking circuit provided by the present invention, it must satisfy The two contacts of "L02G close" and "bus 1M no voltage" (that is, the first close contact k1 and the first voltage contact k2 of the temporary grounding knife) are connected, that is, when the temporary grounding knife L02G is grounded, the "first The 1G voltage transformer of the section busbar has no power in the three phases" before it is allowed to operate the 1G isolation switch. When the temporary grounding knife L02G is not grounded, the sub-point contact of the temporary grounding knife L02G (the first sub-point contact k3 of the temporary grounding knife) is connected, and the above-mentioned blocking circuit is short-circuited to restore the normal blocking wiring as shown in Figure 3. When the isolating switch 2G needs to be installed with a temporary ground wire L02G for maintenance, in order to operate the isolating switch 2G, the two contacts of "L02G close" and "2M no voltage" must be satisfied (that is, the second close contact k4 of the temporary grounding knife, The second voltage contacts k5) are all connected, that is, when the temporary grounding knife L02G is grounded, it is only allowed to operate the isolating switch 2G when the condition that "the voltage mutual inductance of the second busbar 2M and the three phases have no electricity" must be met. When "temporary grounding knife L02G is not grounded", the sub-point contact of temporary grounding knife L02G (the second sub-point contact k6 of temporary grounding knife) is connected, and the above-mentioned blocking circuit is short-circuited to restore the normal blocking wiring as shown in Figure 3.

In the same way, when the isolation switch 1G overhaul needs to be installed with a temporary ground wire L02G, if you want to operate the isolation switch 2G, due to the existence of the temporary ground knife locking circuit c of the electrical five-proof locking circuit provided by the present invention, the "L02G" must be satisfied. The two contacts of "closed" and "2M no voltage" (i.e. the second closed contact k4 and the second voltage contact k5 of the temporary grounding knife) are both connected, that is, when the temporary grounding knife L02G is grounded, the "second bus 2M The voltage mutual inductance and the three phases have no power" is allowed to operate the isolating switch 2G. When "temporary grounding knife L02G is not grounded", the sub-point contact of temporary grounding knife L02G (the second sub-point contact k6 of temporary grounding knife) is connected, and the above-mentioned blocking circuit is short-circuited to restore the normal blocking wiring as shown in Figure 3. When the isolation switch 1G needs to be installed with a temporary ground wire L02G, if you want to operate the isolation switch 1G, you must meet the two contacts of "L02G close" and "bus 1M no voltage" (that is, the first close contact of the temporary grounding knife k1 , the first voltage contact k2) are all connected, that is, when the temporary grounding knife L02G is grounded, the 1G isolating switch must be operated only when "the first busbar 1M voltage transformer has no power in three phases". When the temporary grounding knife L02G is not grounded, the sub-point contact of the temporary grounding knife L02G (the first sub-point contact k3 of the temporary grounding knife) is connected, and the above-mentioned blocking circuit is short-circuited to restore the normal blocking wiring as shown in Figure 3.

Therefore, through the electrical five-proof locking circuit provided by the present invention, when the "temporary grounding wire is in the access position", only when the corresponding busbar three-phase voltage is absent, the corresponding isolation switch is allowed to operate. The newly added locking circuit is short-circuited at the access position, and the original locking state is restored without affecting other operations. An additional unlocking circuit is also required. Therefore, the newly added locking circuit in this issue is only for the temporary ground wire after it is put into use. Only when it works, it has good pertinence, can effectively prevent accidents with temporary grounding wires from accidentally closing the isolating switch, and can also avoid accidental unlocking, and is self-adaptive.

This invention subverts the previous method of relying on human management to ensure that the temporary ground wire does not have malicious misoperation. Due to human reasons, the wrong interval often occurs, and the method of manual unlocking leads to malicious misoperation. The new blocking circuit will be from human defense to technical defense. change. As long as the temporary grounding wire (i.e. the temporary grounding knife in the present invention) is hung up, the isolating switch on the side of the bus bar where the voltage relay is charged during the maintenance interval will not be able to operate, so as to prevent the occurrence of vicious misoperation, but the normal switching operation will Without any influence, this kind of comprehensive anti-misoperation locking circuit using voltage and switching values is self-adaptive and reliable.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still understand the foregoing The technical solutions recorded in each embodiment are modified, or some of the technical features are replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (9)

1. a kind of electrical five-defence block circuit, including earthing locked loop, the first isolating-switch locking circuit of bus bar side, The third isolating-switch locking circuit in two isolating-switch locking circuits and line side, which is characterized in that further include: temporary grounding knife Locked loop；

In first isolating-switch locking circuit and second isolating-switch locking circuit, the first disconnecting switch quartile is connect Point is connect by the temporary grounding knife locked loop with common node, and the second disconnecting switch quartile contact is temporarily connect by described Earthing knife-switch locked loop is connect with the common node；

Wherein, the common node is that the first disconnecting switch quartile contact and the second disconnecting switch quartile contact are connected to same place Node；

After temporary grounding knife ground connection, the temporary grounding knife locked loop is connected to or disconnects according to busbar voltage.

2. electrical five-defence block circuit according to claim 1, which is characterized in that the second disconnecting switch quartile contact The temporary grounding knife locked loop between the common node includes: temporary grounding knife the first coincidence contact and the first electricity Crimping point；

The common node, the first coincidence of temporary grounding knife contact, the first voltage contact and described second are kept apart Quartile contact is closed to be sequentially connected；

Wherein, the first temporary grounding knife coincidence contact is connected to or disconnects according to the ground state of the temporary grounding knife.Institute First voltage contact is stated to be connected to or disconnect according to the voltage of the first bus corresponding with the first disconnecting switch.

3. electrical five-defence block circuit according to claim 2, which is characterized in that the first disconnecting switch quartile contact The temporary grounding knife locked loop between the common node includes: temporary grounding knife the second coincidence contact and the second electricity Crimping point；

The common node, the second coincidence of temporary grounding knife contact, the second voltage contact and described first are kept apart Quartile contact is closed to be sequentially connected；

Wherein, temporary grounding knife the second coincidence contact is connected to or disconnects according to the ground state of the temporary grounding knife.Institute Second voltage contact is stated to be connected to or disconnect according to the voltage of the second bus corresponding with the second disconnecting switch.

4. electrical five-defence block circuit according to claim 3, which is characterized in that the second disconnecting switch quartile contact The temporary grounding knife locked loop between the common node further include: temporary grounding knife the first quartile contact；

The branch and the temporary grounding knife first that the first coincidence of temporary grounding knife contact, the first voltage contact are constituted Quartile contact is in parallel.

5. electrical five-defence block circuit according to claim 4, which is characterized in that the first disconnecting switch quartile contact The temporary grounding knife locked loop between the common node further include: temporary grounding knife the second quartile contact；

The branch and the temporary grounding knife second that the second coincidence of temporary grounding knife contact, the second voltage contact are constituted Quartile contact is in parallel.

6. according to claim 1 to electrical five-defence block circuit described in 5 any one, which is characterized in that described electrical five is anti- Each contact in locked loop is the contact of relay.

7. electrical five-defence block circuit according to claim 6, which is characterized in that the first voltage contact and described Two voltage points are the contact that three-phase is no-voltage relay.

8. electrical five-defence block circuit according to claim 7, which is characterized in that the equal no-voltage relay inspection of three-phase Survey the voltage of A630, B630, C630 and N600 on bus.

9. electrical five-defence block circuit according to claim 8, which is characterized in that as the A630, B630, described Voltage between C630 and the N600 is respectively less than when can adjust low pressure definite value 1, and the equal no-voltage relay of three-phase detects bus For no-voltage.