CN109327009B - Method for preventing misoperation of dangerous pressing plate during circuit breaker protection scheduled inspection - Google Patents
Method for preventing misoperation of dangerous pressing plate during circuit breaker protection scheduled inspection Download PDFInfo
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- CN109327009B CN109327009B CN201810961576.2A CN201810961576A CN109327009B CN 109327009 B CN109327009 B CN 109327009B CN 201810961576 A CN201810961576 A CN 201810961576A CN 109327009 B CN109327009 B CN 109327009B
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- circuit breaker
- breaker
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/02—Details
- H02H3/05—Details with means for increasing reliability, e.g. redundancy arrangements
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Abstract
The invention discloses a method for preventing mistaken throwing of a dangerous pressing plate during the regular inspection of circuit breaker protection, which is characterized in that a mistaken throwing preventing loop is added in the existing circuit with the risk of mistaken collision during the stopping interval and the related running interval, the outlet of a device is controlled by the state of the pressing plate, the protection is locked in the state of the regular inspection, the protection can be released only when all the pressing plates related to the running interval are in the withdrawing state, and the protection function of the device is in the locking state and cannot be output when one or more pressing plates related to the running are mistakenly thrown. The use of the invention can reduce the cost of each time of the regular inspection, and the function is realized by adopting the self-feedback of the device, the error operation of the pressing plate is not caused by the influence of personnel factors, the risk of operation interval misoperation caused in the process of the regular inspection of the line is fundamentally avoided, and the invention has stronger popularization and application values.
Description
Technical Field
The invention relates to the technical field of relay protection, in particular to a method for preventing misoperation of a dangerous pressing plate during regular detection of circuit breaker protection.
Background
As is well known, the relay protection miss-collision risk belongs to one of three mistakes, and the consequence is serious. If the 220kV line protection is checked regularly, the 220kV mother-to-mother differential pressure plate is thrown in a fault and started in a failure mode, the 220kV mother-to-mother differential misoperation can be caused, serious accidents at all intervals on the mother-to-mother differential are avoided, irreparable economic losses are caused to a power grid, and a loop of the 220kV line protection starting mother-to-differential failure is shown in fig. 1.
At present, when relay protection personnel carry out scheduled inspection protection (such as line protection), in order to prevent a protection action from misoperation of an operation interval (such as bus differential protection) related to the interval, a pressure plate (A phase start failure, B phase start failure and C phase start failure) related to the operation interval is usually withdrawn, and after the pressure plate is withdrawn, a protection outlet is physically separated from the operation interval, but the pressure plate cannot be guaranteed to be mistakenly thrown by a person in the scheduled inspection process, namely, the pressure plate is influenced by uncertain factors of the person, so that the currently adopted method is to wrap one end, which is connected with the outside and is provided with minus 110V electricity, with an insulating adhesive tape so as to warn and prevent the person from mistakenly throwing the pressure plate. However, this often has the following disadvantages:
1. the insulating tape is easy to fall off, and the insulating tape cannot play the roles of isolating the terminal and preventing the error-throwing pressure plate after falling off;
2. because an additional tool is additionally needed, the insulating tape needs to be used every time, the waste of the insulating tape is caused, and when the tape is forgotten to be taken, the error touch cannot be guaranteed;
3. the insulation tape wrapping is extremely irregular and beautiful.
Since the line protection regular inspection belongs to the conventional operation and the risk of wrong operation is huge, a method for preventing the wrong operation of a dangerous pressing plate in the main transformer protection regular inspection needs to be designed.
Disclosure of Invention
In view of the above, the present invention provides a method for preventing a dangerous pressing plate from being mistakenly thrown during a regular check of a circuit breaker, which can avoid the drawbacks of the existing methods.
The purpose of the invention is realized by the following technical scheme:
the method is characterized in that in a stopping interval and an operation related interval, an anti-misoperation loop is added in a loop with the risk of mistaken collision in the existing protection of the related circuit breaker, the outlet of a device is controlled through a pressure plate state, the protection is locked in a fixed detection state, the protection can be released only when all pressure plates related to the operation interval are in an exit state, and when one or more pressure plates related to the operation are mistakenly thrown in, the protection function of the device is in a locking state and cannot be output.
Particularly, the stopping interval is set as a line protection I, a side breaker and a middle breaker of the line protection I, and the operation related interval is set as a line protection II and an interval breaker thereof;
the method comprises the following steps:
(1) circuit breaker protection to limit circuit breaker:
step 1: an intermediate relay connected with a master differential pressing plate of the failure delay starting A set and a master differential pressing plate of the failure delay starting B set in series is added into a failure delay starting A set of master differential pressing plate (two sets) and a failure delay starting B set of master differential pressing plate (two sets) in a protection screen of the existing side circuit breaker I, the voltage is taken from +110V and-110V of the protection, and when the protection is performed, the intermediate relay is switched into a de-excitation state through the pressing plates;
step 2: taking each pair of normally open contacts of the intermediate relay as a set of mother difference (two sets) of failure delay starting A and a set of mother difference (two sets) of failure delay starting B to open A, B sets of mother difference protection failure opening access contacts;
and step 3: a pair of normally closed contacts of each intermediate relay form a locking loop, and in order to distinguish the regular inspection state and the normal operation state, the total knife switch position of the edge of the shutdown circuit 1 and the breaker position is taken as a locking condition;
(2) circuit breaker protection for medium-sized circuit breakers;
step 1: adding an intermediate relay which is connected with a pressure plate of the breaker protection failure delay jump operation interval breaker and a remote pressure plate of the breaker protection failure delay line protection II auxiliary protection communication device in series into a remote transmission (four groups) loop of the breaker protection failure delay jump operation interval breaker (two groups) and the auxiliary protection communication device of the breaker protection failure delay line protection II in the existing side breaker protection screen, wherein the voltages are taken from +110V and-110V of the protection, and when the protection is performed, the intermediate relay is excited through the pressure plates;
step 2: taking a pair of normally open contacts of the intermediate relay as breaker protection failure delay jump operation interval breakers (two groups), remotely transmitting breaker protection failure delay (four groups) to an interval breaker operation box through a line protection 2 auxiliary protection communication device, remotely transmitting the interval breaker operation box permanent jump contacts (two groups), remotely transmitting line protection II auxiliary A protection (two groups) and remotely transmitting line protection II auxiliary B protection (two groups);
and step 3: a pair of normally closed contacts of the intermediate relay are used for forming a locking loop, and in order to distinguish the scheduled inspection state from the normal operation state, the sum of the positions of the edge of the outage line protection I and the breaker is always used as a locking condition.
The invention has the beneficial effects that:
the use of the invention can reduce the cost (such as an insulating tape) during the regular inspection each time, and the function is realized by adopting the self-feedback of the device, so that the error-throwing pressing plate is not influenced by personnel factors, the risk of operation interval misoperation in the regular inspection process is fundamentally avoided, and the invention has strong popularization and application values.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof.
Drawings
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings, in which:
fig. 1 shows a 5033 side circuit breaker protection starting 500kV a set busbar differential circuit failure circuit;
fig. 2 is a modified 5033 side circuit breaker protection starting 500kV a set of mother-difference circuit failure excitation intermediate locator circuit;
fig. 3 is a diagram of a modified 5033-side circuit breaker protection starting 500kV a set busbar differential circuit failure;
fig. 4 shows a 5033 side circuit breaker protection starting 500kV B set bus differential circuit failure circuit;
fig. 5 is a modified 5033 side circuit breaker protection starting 500kV B set mother-difference circuit failure excitation intermediate locator circuit;
FIG. 6 shows a modified 5033-side circuit breaker protection starting 500kV B-set busbar differential circuit failure circuit;
fig. 7 is a pressure plate anti-false-throw lockout protection circuit (for the side circuit breaker 5033 protection device) in connection with the operation of line 1;
fig. 8 is a latch circuit (for the side breaker 5033 protection device) with the line 1 protection device in a ready condition for a scheduled inspection state;
fig. 9 is a circuit of circuit breaker protection failure delay trip interval circuit breaker 5031 (first group) in 5032;
fig. 10 shows a modified 5032 circuit breaker protection failure delay trip interval circuit breaker 5031 (first group) excitation intermediate relay loop;
fig. 11 is a modified circuit 5032 with a circuit breaker protection failure delay trip interval circuit 5031 (first group);
fig. 12 shows a circuit of the circuit breaker protection failure delay trip interval circuit breaker 5031 (second group) in 5032;
fig. 13 shows a modified 5032 circuit breaker protection failure delay trip interval circuit breaker 5031 (second group) excitation intermediate relay circuit;
fig. 14 shows a modified circuit 5032 with circuit breaker protection failure delay trip interval circuit 5031 (first, second group);
fig. 15 is a circuit diagram of a circuit breaker protection failure delay line protection 2 auxiliary a protection communication device remote transmission circuit in 5032;
fig. 16 is a modified 5032 circuit of the circuit breaker protection failure delay line protection 2 auxiliary a protection communication device remote excitation intermediate relay circuit;
fig. 17 is a modified 5032 remote transmission circuit of the circuit breaker protection failure delay line protection 2 auxiliary a protection communication device;
fig. 18 is a circuit breaker protection failure delay line protection 2 auxiliary B protection communication device remote transmission loop in 5032;
fig. 19 is a modified 5032 circuit of the circuit breaker protection failure delay line protection 2 auxiliary B protection communication device remote excitation intermediate relay circuit;
fig. 20 is a modified 5032 remote transmission loop of the circuit breaker protection failure delay line protection 2 auxiliary B protection communication device;
fig. 21 is a circuit diagram of a protection circuit (protection device for the interrupter 5032) for protection against a jam associated with the operation of the line 1;
fig. 22 shows a latch circuit (for the interrupter 5032 protection device) in a condition where the line 1 protection device is ready for a scheduled test state.
Detailed Description
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are illustrative of the invention only and are not limiting upon the scope of the invention.
The invention relates to a method for preventing mistaken throwing of a dangerous pressing plate during the regular inspection of the protection of a circuit breaker, which is characterized in that a mistaken throwing preventing loop is added in the existing circuit which is protected by the circuit breaker and has the mistaken touching risk in a stopping interval and a related operating interval, the outlet of a device is controlled by the state of the pressing plate, the protection is locked in the state of the regular inspection, the protection can be released only when all the pressing plates related to the operating interval are in an exit state, and the protection function of the device is in a locking state and cannot be output when one or more pressing plates related to the operation are mistakenly thrown.
In the present invention, taking the regular inspection of 500kV line protection 1 as an example, the shutdown interval is line protection 1 and its side circuit breaker 5033 and middle circuit breaker 5032, and the operation related interval is line protection 2 and its interval circuit breaker 5031.
(1) The 500kV 3/2 wired edge breaker 5033 protects the pressure plate at risk of misputting comprises: a sets of mother differential pressure plates (two sets) are started in a failure delay way, and B sets of mother differential pressure plates (two sets) are started in a failure delay way;
(2) the 500kV 3/2 wired interrupt 5032 protection pressure plate at risk of misputting includes: a failure delay jumping 5031 three-phase (first group) pressing plate, a failure delay jumping 5031 three-phase (second group) pressing plate, a failure delay line protection 2 communication device command 1 remote transmission pressing plate, a failure delay line protection 2 communication device command 2 remote transmission pressing plate, a failure delay line protection 2 communication device command 3 remote transmission pressing plate and a failure delay line protection 2 communication device command 4 remote transmission pressing plate;
needle-to-edge circuit breaker 5033 circuit breaker protection screen: (see FIGS. 1-8)
Step 1: an intermediate relay (K1-K4) which is connected with the A set of female differential pressure plates for failure delay starting and the B set of female differential pressure plates for failure delay starting in series is added into the A set of female differential pressure plates for failure delay starting and the B set of female differential pressure plates for failure delay starting (two sets) in the protection screen of the existing side circuit breaker 5033, the voltage is taken from +110V and-110V of the protection, and when the protection is performed, the de-excitation intermediate relay (K1-K4) is put in through the pressure plates;
step 2: taking a pair of normally open contacts of intermediate relays K1, K2, K3 and K4 as a set of mother difference (two sets) of failure delay starting A and a set of mother difference (two sets) of failure delay starting B to be respectively opened to a set of mother difference protection failure opening access contact of 500kV A and a set of mother difference protection failure access contact of B;
and step 3: a pair of normally closed contacts of intermediate relays K1, K2, K3 and K4 are used for forming a locking loop, and in order to distinguish the regular detection state from the normal operation state, the total knife switch position of the side of the shutdown circuit 1 and the breaker position is used as a locking condition.
When the master differential pressing plates of the A set of the failure delay starting coil (two sets) and the B set of the master differential pressing plates of the failure delay starting coil (two sets) are all in the exit state, the coil of the unlocking relay is in the power-on state, the protection is in the unlocking state, at the moment, the master differential pressing plates of the A set of the failure delay starting coil (two sets) and any one pressing plate of the master differential pressing plates of the B set of the failure delay starting coil (two sets) are put into use, normally closed contacts of the intermediate relays corresponding to the master differential pressing plates can be disconnected, the coil of the unlocking relay is powered off, the protection function returns to the locking state, and the coil.
Centering the circuit breaker 5032 protection screen: (see FIGS. 9-22)
Step 1: in the circuit loop (four groups) of the circuit breaker protection failure delay jump operation interval circuit breakers 5031 (two groups) in the protection screen 5032 of the existing side circuit breaker 5032 and the circuit breaker protection failure delay in the 5032 are remotely transmitted through the auxiliary protection communication device of the circuit protection 2, an intermediate relay (K5-K10) which is connected with a pressure plate of the circuit breaker protection failure delay jump operation interval circuit breaker 5031 in the 5032 and the circuit breaker protection failure delay in the circuit breaker protection failure delay jump operation interval circuit breaker in the 5032 in series through the remote pressure plate of the auxiliary protection communication device of the circuit protection 2 is added, the voltage is taken from +110V and-110V of the protection, and when the protection is performed, the de-excitation intermediate relay (K5-K10) is put;
step 2: a pair of normally open contacts of each of the intermediate relays K5-K10 are taken as breaker protection failure delay jump operation interval breakers 5031 (two groups) in 5032, breaker protection failure delay in 5032 is remotely transmitted (four groups) to the side breaker 5031 operation box permanent jump contacts (two groups) through a line protection 2 auxiliary a protection remote transmission access (two groups), and a line protection 2 auxiliary B protection remote transmission access (two groups) respectively;
and step 3: a pair of normally closed contacts of each of the intermediate relays K5-K10 are used for forming a locking loop, and in order to distinguish the regular detection state from the normal operation state, the sum of the positions of the edge of the shutdown circuit 1 and the breaker is used as a locking condition.
When the circuit breaker protection failure delay jump operation interval circuit breaker 5031 pressure plates (two groups) in 5032 and the circuit breaker protection failure delay line circuit protection 2 auxiliary protection communication device remote pressure plates (four groups) in 5032 are in an exit state, the coil of the unlocking relay is in a power-on state, and the protection is in an unlocking state, at the moment, when the circuit breaker protection failure delay jump operation interval circuit breaker 5031 pressure plates (two groups) in 5032 and the circuit breaker protection failure delay line protection 2 auxiliary protection communication device remote pressure plates (four groups) in 5032 are put into use, the normally closed contact of the corresponding intermediate relay is disconnected, so that the coil of the unlocking relay is powered off, the protection function returns to the locking state, and the circuit breaker protection function cannot be exported.
The invention realizes the function by adopting the self-feedback of the device, and the device is not influenced by personnel factors to cause the error operation of the pressing plate, thereby fundamentally avoiding the risk of operation interval misoperation in the process of the regular inspection.
Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.
Claims (2)
1. A method for preventing mistaken operation of a dangerous pressing plate during regular detection of circuit breaker protection is characterized by comprising the following steps: the method is characterized in that an anti-misoperation loop is added in a circuit with the risk of mistaken collision in the existing protection of the related circuit breaker in a stopping interval and a related operating interval, the outlet of the device is controlled through the state of a pressure plate, the device is protected to be locked in a fixed detection state, the protection can be released only when all the pressure plates related to the operating interval are in an exit state, and the protection function of the device is in a locking state and cannot be released when one or more pressure plates related to the operation are mistakenly thrown in.
2. The method of claim 1 for preventing accidental pressing plate operation at risk during regular check of circuit breaker protection, characterized in that: setting the stopping interval as a line protection I, a side circuit breaker and a middle circuit breaker of the line protection I, and setting the running related interval as a line protection II and an interval circuit breaker thereof;
the method comprises the following steps:
(1) circuit breaker protection to limit circuit breaker:
step 1: adding an intermediate relay which is connected with a master differential pressing plate of the failure delay starting A set and a master differential pressing plate of the failure delay starting B set in series into the master differential pressing plate of the failure delay starting A set and the master differential pressing plate of the failure delay starting B set in the protection screen of the existing two sets of side circuit breakers I, wherein the voltage is taken from +110V and-110V of the protection, and when the protection acts, the intermediate relay is switched into and switched out of excitation through the pressing plates;
step 2: taking each pair of normally open contacts of the intermediate relay as two sets of mother differences of failure delay starting A and two sets of mother differences of failure delay starting B respectively to A, B sets of mother difference protection failure opening contacts;
and step 3: a pair of normally closed contacts of each intermediate relay form a locking loop, and in order to distinguish the regular inspection state and the normal operation state, the total knife switch position of the edge of the shutdown circuit 1 and the breaker position is taken as a locking condition;
(2) circuit breaker protection for medium-sized circuit breakers;
step 1: adding an intermediate relay which is connected with a breaker protection failure delay jump operation interval breaker pressing plate and an breaker protection failure delay line protection II auxiliary protection communication device remote transmission pressing plate in series in the auxiliary protection communication device remote transmission loop of two groups of breaker protection failure delay jump operation interval breakers and four groups of breaker protection failure delay line protection II in the existing side breaker protection screen, wherein the voltage is taken from +110V and-110V of the protection, and when the protection is performed, the intermediate relay is switched into de-excitation through the pressing plates;
step 2: taking a pair of normally open contacts of the intermediate relay as two groups of circuit breaker protection failure delay jump operation interval circuit breakers respectively, and remotely transmitting the protection failure delay of the four groups of circuit breakers to two groups of circuit breaker operation boxes through a line protection 2 auxiliary protection communication device to open the circuit breakers in a permanent jump contact mode, two groups of line protection II auxiliary A protection remote transmission opening mode and two groups of line protection II auxiliary B protection remote transmission opening mode;
and step 3: a pair of normally closed contacts of the intermediate relay are used for forming a locking loop, and in order to distinguish the scheduled inspection state from the normal operation state, the sum of the positions of the edge of the outage line protection I and the breaker is always used as a locking condition.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810961576.2A CN109327009B (en) | 2018-08-22 | 2018-08-22 | Method for preventing misoperation of dangerous pressing plate during circuit breaker protection scheduled inspection |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810961576.2A CN109327009B (en) | 2018-08-22 | 2018-08-22 | Method for preventing misoperation of dangerous pressing plate during circuit breaker protection scheduled inspection |
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| CN109327009A CN109327009A (en) | 2019-02-12 |
| CN109327009B true CN109327009B (en) | 2020-01-07 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202142905U (en) * | 2011-05-25 | 2012-02-08 | 广东电网公司深圳供电局 | Logic device for shutting mistaken switching of spare power source automatic switch device of power supply |
| CN204204683U (en) * | 2014-09-18 | 2015-03-11 | 国家电网公司 | The anti-misoperation protective cover of protection pressing plate |
| CN104734349A (en) * | 2015-03-03 | 2015-06-24 | 南京国电南自电网自动化有限公司 | Automatic pressing plate inputting and retreating method based on secondary equipment self-inspection in intelligent substation |
| CN108318769A (en) * | 2018-04-17 | 2018-07-24 | 国网河南省电力公司电力科学研究院 | A kind of intelligent substation busbar protective device pressing plate state alarm method and device |
-
2018
- 2018-08-22 CN CN201810961576.2A patent/CN109327009B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202142905U (en) * | 2011-05-25 | 2012-02-08 | 广东电网公司深圳供电局 | Logic device for shutting mistaken switching of spare power source automatic switch device of power supply |
| CN204204683U (en) * | 2014-09-18 | 2015-03-11 | 国家电网公司 | The anti-misoperation protective cover of protection pressing plate |
| CN104734349A (en) * | 2015-03-03 | 2015-06-24 | 南京国电南自电网自动化有限公司 | Automatic pressing plate inputting and retreating method based on secondary equipment self-inspection in intelligent substation |
| CN108318769A (en) * | 2018-04-17 | 2018-07-24 | 国网河南省电力公司电力科学研究院 | A kind of intelligent substation busbar protective device pressing plate state alarm method and device |
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| CN109327009A (en) | 2019-02-12 |
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