CN110932227B - Method for replacing protection device without power outage - Google Patents
Method for replacing protection device without power outage Download PDFInfo
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- CN110932227B CN110932227B CN201911264140.9A CN201911264140A CN110932227B CN 110932227 B CN110932227 B CN 110932227B CN 201911264140 A CN201911264140 A CN 201911264140A CN 110932227 B CN110932227 B CN 110932227B
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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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- 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
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Abstract
The invention adopts a method for replacing a protection device without power failure, the method connects a standby protection device into a power supply line through a protection current switch connected with the output end of a protection current transformer in series, removes the original protection device under the protection of the standby protection device, and installs, debugs and puts into use a new device, thereby solving the problem that the protection device can not be replaced in a charged way. The method adds a protection current switch which is connected in series with the output end of the protection current transformer to the original line reconstruction, and has the advantages of simple reconstruction, mature technology, low material cost and good universality; the replacement steps are few, the operation is simple, and the operability is strong. The power system is ensured to supply power continuously, more economic benefits are gained for power supply companies and clients, and the use experience of users is improved.
Description
Technical Field
The invention belongs to the technical field of electric power overhaul, and particularly relates to a method for replacing a protection device of a transformer substation.
Background
The protection device is used as a safety component for monitoring the abnormity and the fault of the power system and responding in time, and is particularly important for the safe and economic operation of the power system. The protection circuit is used as a part of an electric power system, and a voltage input end and a current input end are sequentially connected with an output end of protection voltage and an output end of protection current; the control output end of the protection device sends a control signal to a circuit breaker connected in series with a power supply line according to internal logic judgment to control the opening and closing actions of the circuit breaker, and the protection device adopts an external power supply to supply power such as AC 220V. The circuit breaker is connected in series with a power supply line, is used for cutting off or closing no-load current and load current in the power supply line, receiving a control signal of the protection device when a system breaks down, and cutting off overload current and short-circuit current, and comprises an energy storage motor and a mechanical structure, wherein the energy storage motor is used for opening and closing coils, and is used for storing mechanical energy during opening and closing actions. The protection voltage transformer used as the protection voltage signal acquisition end of the power supply line is incorporated into the power supply line at the primary side and is used as the output end of the protection voltage at the secondary side. The power supply line passes through the inside of an iron core of the power supply line, and the output end of the power supply line is used as the output end of the protection current. According to the structure and the principle, the output of the voltage transformer cannot be short-circuited, and the output of the current transformer cannot be open-circuited; the inventor finds that the protection current transformer cannot be disconnected in an electric power system, and the key point of preventing the protection device from being replaced in a non-power-off mode is the protection current transformer. The power distribution cabinet comprises an instrument for analyzing the running state and technical indexes of the power system, can display and record various parameters including phase voltage, current, active power, reactive power and power factors of each phase, and is high in required accuracy and good in real-time performance.
The method for replacing the protection device of the power system comprises the following steps: after the power failure of the power system is confirmed, the power supply, the protection voltage input end, the protection current input end and the control signal output end of the original protection device are disconnected with the outside, and the original protection device is removed; then connecting a power supply, a protection voltage input end, a protection current input end and a control output end of the new protection device with corresponding external terminals; turning on a power supply of the new protection device, transmitting power to the power system, and putting the new protection device into use after the new protection device is qualified in debugging; the new protection device comprises a complete protection device to be accessed or an original protection device qualified through overhaul. Therefore, the method for replacing the protection device in power failure brings inconvenience to production and life, and influences the experience of a large number of users.
The invention content is as follows:
in order to solve the problems in the background art, the invention adopts a method for replacing the protection device without power failure; the method introduces a standby protection device and continues the protection work when the original protection device exits the power system.
The invention adopts the following technical scheme:
a method for replacing a protection device without power failure comprises the following steps:
one end of each of the two temporary protection current input lines is connected with two ends of a protection current switch, the other end of each temporary protection current input line is connected with a current signal input end of a standby protection device, the protection current switches are connected in series with output ends of protection current transformers, and one of the protection current switches is always in a closed state; the voltage input end of the standby protection device is connected with the output end of the protection voltage transformer; the control output end of the standby protection device is connected with the input end of a circuit breaker connected in series with a power supply line; connecting a standby protection device power supply; and powering on the standby protection device, disconnecting the protection current switch and putting the standby protection device into use.
After the original protection device is powered off, two protection current input lines connected with the current input end of the original protection device are in short circuit connection; the current input end, the voltage input end, the control output end and the power supply end of the power supply are disconnected with the outside; and keeping the two protection current input lines in a short-circuit state all the time, and removing the original protection device.
Connecting the voltage input of the new protection device with the output end of the protection voltage transformer; the control output end of the new protection device is connected with the input end of a circuit breaker connected in series with a power supply line; connecting a protection current input line to a current input end of a new protection device, keeping the previous short-circuit state all the time, and connecting a power supply of the new protection device; the new protection device is powered on, and two protection current input lines which are always kept in a short-circuit state before the new protection device is disconnected; debugging the new protection device to be qualified; the new protection device comprises an accessed intact protection device or an original protection device qualified through overhaul.
Powering off the standby protection device and closing the protection current switch; the current input end, the voltage input end, the control output end and the power supply end of the power supply are disconnected with the outside; and after the standby protection device is removed, the new protection device is put into use.
The further improvement is that the standby protection device firstly confirms to be qualified, sets internal parameters in advance, and then starts to wire and use.
The protection current input temporary line is connected to two ends of the protection current switch in parallel, and the output end of the external current transformer is used as the output end of the protection current and connected with the current input end of the standby protection device.
The further improvement lies in that before the control output end of the standby protection device is connected with the input end of the circuit breaker connected in series with a power supply line, the opening, closing and energy storage motor coils of the circuit breaker are firstly confirmed, so that the circuit breaker is ensured to be free of circuit breaking, and the resistance value is in a reasonable range.
The further improvement lies in that: after the opening and closing of the circuit breaker and the energy storage motor coil are confirmed, the opening and closing records of the circuit breaker within one year are taken, the fact that the circuit breaker has been mechanically operated recently is confirmed, the structure is reliable, and the action is free of abnormity.
The further improvement is that before the standby protection device is electrified for the first time, the corresponding relation between the phase sequence, the polarity and the voltage input end and the current input end is confirmed.
The further improvement is that after the corresponding relation between the voltage input end and the current input end of the standby protection device is confirmed, before the standby protection device is connected with the control output end, the standby protection device is powered on and a display menu of the standby protection device is called out, and after the current and the voltage are confirmed to be consistent with the display of the instrument on the power distribution cabinet, the standby protection device is powered off to perform the next operation.
The further improvement lies in that when the voltage input end of the original protection device is disconnected, an insulating sleeve is sleeved on a metal exposed part of each input line connected with the input end of the voltage transformer to prevent short circuit when the input line is disconnected.
The further improvement is that before the new protection device is powered on for the first time, the corresponding relation between the phase sequence, the polarity and the voltage input end and the current input end is confirmed.
The further improvement is that before the standby protection device is powered off, the new protection device calls a display menu, and after the current and the voltage are confirmed to be consistent with the instrument display on the power distribution cabinet, the next operation is carried out.
The invention has the following positive effects:
compared with the prior art, the invention adopts a method for replacing the protection device without power failure, which comprises the following steps: according to the method, the protection current switch connected with the protection current transformer in series is used for connecting the standby protection device into a power supply line, the original protection device is removed under the protection of the standby protection device, and the new device is installed, debugged and put into use, so that the problem that the protection device cannot be replaced in a charged mode is solved. The method adds a protection current switch which is connected in series with the output end of the protection current transformer to the original line reconstruction, and has the advantages of simple reconstruction, mature technology, low material cost and good universality; the protection device is replaced on the premise that the standby protection device protects the power supply line, and the safety of the power supply line is guaranteed; the replacement steps are few, the operation is simple, and the operability is strong. The power system is ensured to supply power continuously, more economic benefits are gained for power supply companies and clients, and the use experience of users is improved.
Drawings
FIG. 1 is a schematic view of a modification of the terminal and external connections of the protection device;
FIG. 2 is a simplified schematic diagram of FIG. 1;
FIG. 3 is a schematic representation of an alternate step of an embodiment of the present invention;
FIG. 4 is a schematic diagram of a connection according to an embodiment of the present invention;
FIG. 5 is a schematic diagram of a second replacement step according to the embodiment of the present invention;
fig. 6 is a schematic connection diagram according to a second embodiment of the invention.
Detailed Description
Example one
The terminal and wiring diagram of the protection device are shown in fig. 1, and the control output ends are CC1, CO1 and COM1, specifically meaning the closing control output end, the opening control output end and the control output common end, which are connected with the closing coil input end, the opening coil input end and the opening and closing coil common input end of the circuit breaker connected in series to the power supply line; VA1, VB1, VC1 and VN1 are used as voltage input ends, specifically, A, B, C phase voltage input ends and voltage input common ends are respectively connected with A, B, C phase sequence protection voltage transformer phase output ends and common ends; the input ends of the protection voltage transformers (TVA, TVB and TVC) are connected in parallel to a power supply line; AA1, AB1, AC1 and AN1 are used as current input ends, specifically, A, B, C phase current input ends and current input common ends are respectively connected with A, B, C phase sequence protection current transformer phase output ends and common ends; the power supply line passes through the inside of the iron core of the protective current transformer (TAA, TAB, TAC). L, N, PE is used as the input terminal of the power supply and is connected with the external power supply.
The invention relates to a further improvement of a power supply line, wherein switches are arranged on protection current output lines of all phases, TAA output lines AL1 are taken as an example (the other output lines of all phases are AL 1), a switch S1 is connected into AL1 in parallel through terminals N10 and N11 of the switch S1, and a lead of AL1 between N10 and N11 is disconnected; two terminals N12 and N13 are arranged at two ends of the switch S1.
For the method involving shorting of the protection current lines, the TAB output line AL2 (the remaining phase outputs are the same as AL 2) is used to connect AL2 to AN1 via a temporary shorting line LL 1.
For convenience of explanation and appropriate reduction of system complexity, the schematic diagram of fig. 1 is further simplified as shown in fig. 2, the control output end of the protection device is simplified as N2, the input end of each phase voltage is simplified as N3, the input end of each phase current is simplified as N4, and the common end of the current input is N5.
The replacement step is as shown in fig. 3, one end of each of two protection current input temporary lines L3 and L4 in fig. 4 is respectively connected to two ends N12 and N13 of a protection current switch S1, and the other end is connected to current signal input ends N8 and N9 of a standby protection device, at this time, the protection current switch S1 is in a closed state; the voltage input end N7 of the standby protection device is connected with the output end of a protection voltage transformer TV 1; the control output end N6 of the standby protection device is connected with the input end QF1 of the circuit breaker connected in series with the power supply line; connecting a standby protection device power supply; the standby protection device is powered on, and a protection current switch S1 connected in series with the protection current transformer is disconnected, so that the standby protection device is put into use.
When the original protection device is powered off, two protection current input lines connected with current input ends N4 and N5 of the original protection device are in short circuit through a protection current input temporary line L5; disconnecting the current input ends N4 and N5, the voltage input end N3, the control output end N2 and the connection N1 of a power supply end and the outside; it is ensured that both protection current input lines L1, L2 are always in a short-circuited state.
Connecting a voltage input end N3 of the new protection device with an output end of a protection voltage transformer TV 1; the control output end N2 of the new protection device is connected with the input end of a breaker QF1 of a power supply line in series; connecting the protection current input lines L1 and L2 to the current input ends N4 and N5 of the new protection device; connecting a new protection device power supply; the new protection device is powered on, and two protection current input lines L1 and L2 which are kept in a short-circuit state until the new protection device is powered on are disconnected; debugging the new protection device to be qualified; the new protection device comprises an accessed intact protection device or an original protection device qualified through overhaul.
Powering off the standby protection device and closing the protection current switch S1; the current input ends N8 and N9, the voltage input end N7, the control output end N6 and the power supply end are disconnected with the outside; after the spare protection device is removed, the new protection device is put into use.
Example two
The replacing steps are shown in fig. 5, and this embodiment is a further improvement of the first embodiment, and the differences are that: the standby protection device firstly confirms the qualification and sets internal parameters in advance. For the standby protection device of the external current transformer, a protection current input temporary line L5 in fig. 6 passes through the inside of the iron core of the external current transformer TA2, two ends of the protection current input temporary line are respectively connected with terminals N12 and N13 of a protection switch S1, an output end of the external current transformer TA2 is used as an output end of a protection current signal, and current input terminals N8 and N9 of the standby protection device are connected through output lines L3 and L4.
Before the output end of the standby protection device is connected, the opening and closing of a circuit breaker and an energy storage motor coil are confirmed, so that the circuit breaker is ensured to be free of circuit breaking, and the resistance value is in a reasonable range; the opening and closing records of the circuit breaker within one year are taken, and the fact that the circuit breaker has been mechanically operated recently is confirmed, so that the structure is reliable, and the action is not abnormal; before the standby protection device is electrified for the first time, the corresponding relation between a phase sequence, a polarity and a voltage input end N7 and current input ends N8 and N9 is confirmed; and electrifying and calling out a display menu of the standby protection device, confirming that the current and the voltage are consistent with the display of the instrument on the power distribution cabinet, then cutting off the power, connecting a control output end N6 of the protection device with a corresponding connecting terminal of a breaker QF1, electrifying the standby protection device, and disconnecting a protection current switch S1, wherein the standby protection device is put into use.
After the original protection device is powered off, when the protection voltage input end N3 of the original protection device is disconnected, each input line connected with the voltage input end N3 is disconnected, the metal exposed part of the input line is sleeved with an insulating sleeve, and short circuit is prevented.
Before the new protection device is electrified, the corresponding relation between a phase sequence, a polarity and a voltage input end N3 and current input ends N4 and N5 is confirmed; the new protection device calls out a display menu to confirm that the current and the voltage are consistent with the instrument display on the power distribution cabinet.
The second embodiment is an improvement of the first embodiment, the first embodiment is refined from the processes of connecting a standby protection device and a new protection device and dismantling an original protection device respectively, for example, before the standby protection device is connected, the reliability of an internal coil and a mechanical device of a circuit breaker is confirmed, under the condition that a control output end is not connected, the input and corresponding relation of each phase voltage and current is confirmed, when the original protection device is dismantled, a protection voltage input line is well protected to prevent short circuit, and the work aims to improve the safety of the device which is guaranteed to be replaced without power outage and reduce the possibility of power failure of a power system caused by misoperation.
The embodiments described above are only preferred embodiments of the invention and are not exhaustive of the possible implementations of the invention. Any obvious modifications to the above would be obvious to those of ordinary skill in the art, but would not bring the invention so modified beyond the spirit and scope of the present invention.
Claims (8)
1. A method for replacing a protection device without power failure is characterized by sequentially comprising the following steps:
the standby protection device firstly confirms the qualification and sets internal parameters in advance;
one end of each of the two temporary protection current input lines is connected with two ends of a protection current switch, the other end of each temporary protection current input line is connected with a current signal input end of a standby protection device, the protection current switches are connected in series with output ends of protection current transformers, and one of the protection current switches is always in a closed state;
the voltage input end of the standby protection device is connected with the output end of the protection voltage transformer; the control output end of the standby protection device is connected with the input end of a circuit breaker connected in series with a power supply line; connecting a standby protection device power supply; the standby protection device is electrified, the protection current switch is switched off, and the standby protection device is put into use;
after the original protection device is powered off, two protection current input lines connected with the current input end of the original protection device are in short circuit connection; the current input end, the voltage input end, the control output end and the power supply end of the power supply are disconnected with the outside; keeping the two protection current input lines in a short circuit state all the time, and removing the original protection device;
connecting the voltage input of the new protection device with the output end of the protection voltage transformer; the control output end of the new protection device is connected with the input end of a circuit breaker connected in series with a power supply line; connecting a protection current input line to a current input end of a new protection device, keeping the previous short-circuit state all the time, and connecting a power supply of the new protection device; the new protection device is powered on, and two protection current input lines which are always kept in a short-circuit state before the new protection device is disconnected; debugging the new protection device to be qualified; the new protection device comprises an accessed intact protection device or an original protection device qualified through maintenance;
the standby protection device is powered off, the protection current switch is closed, all terminals of the protection current switch are disconnected with the outside, and the new protection device is put into use;
for the standby protection device of the external current transformer, a protection current passing through the inside of an iron core of the external current transformer is input into a temporary line and is connected with a protection current switch in parallel, and the output end of the external current transformer is connected with the current input end of the standby protection device.
2. The method for replacing a protection device without power outage of claim 1, wherein: before the control output end of the standby protection device is connected with the input end of a circuit breaker connected in series with a power supply line, the opening, closing and energy storage motor coils of the circuit breaker are firstly confirmed, the circuit breaker is ensured not to be broken, and the resistance value is in a reasonable range.
3. The method for replacing a protection device without power outage as claimed in claim 2, wherein: after the opening and closing of the circuit breaker and the energy storage motor coil are confirmed, the opening and closing records of the circuit breaker within one year are taken, the fact that the circuit breaker has been mechanically operated recently is confirmed, the structure is reliable, and the action is free of abnormity.
4. A method of replacing a protective device without power outage as claimed in claim 3, wherein: before the standby protection device is electrified for the first time, the corresponding relation between a phase sequence, a polarity and a voltage input end and a current input end is confirmed.
5. The method for replacing a protection device without power outage as claimed in claim 4, wherein the method comprises the following steps: after the corresponding relation between the voltage input end and the current input end of the standby protection device is confirmed, before the standby protection device is connected with the control output end, the standby protection device is powered on and a display menu of the standby protection device is called out, the current and the voltage are confirmed to be consistent with the display of the instrument on the power distribution cabinet, and then the standby protection device is powered off to carry out the next operation.
6. The method for replacing a protection device without power outage of claim 1, wherein:
when the original protection device is disconnected from the voltage input end, an insulating sleeve is sleeved on a metal exposed part of each input line connected with the voltage input end when the input line is disconnected, so that short circuit is prevented.
7. The method for replacing a protection device without power outage of claim 1, wherein: before the new protection device is electrified for the first time, the corresponding relation between the phase sequence, the polarity and the voltage input end and the current input end is confirmed.
8. The method for replacing a protection device without power outage of claim 1, wherein: before the standby protection device is powered off, the new protection device calls a display menu, and after the current and the voltage are confirmed to be consistent with the instrument display on the power distribution cabinet, the next operation is carried out.
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| CN201911264140.9A CN110932227B (en) | 2019-12-11 | 2019-12-11 | Method for replacing protection device without power outage |
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| CN201911264140.9A CN110932227B (en) | 2019-12-11 | 2019-12-11 | Method for replacing protection device without power outage |
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| CN110932227A CN110932227A (en) | 2020-03-27 |
| CN110932227B true CN110932227B (en) | 2022-03-01 |
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| CN113507072B (en) * | 2021-07-04 | 2023-02-14 | 国网辽宁省电力有限公司锦州供电公司 | Method for replacing 10kV relay protection device in live mode |
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| CN2888718Y (en) * | 2006-03-29 | 2007-04-11 | 门宇华 | A non-stop DC operated power supply device for substation |
| CN103532096B (en) * | 2013-10-18 | 2017-07-18 | 国家电网公司 | 10kV feeder protection equipments, which do not have a power failure, eliminates defect method |
| CN203734299U (en) * | 2014-03-19 | 2014-07-23 | 江苏沙洲电气有限公司 | Relay protection system |
| CN108594072A (en) * | 2018-04-19 | 2018-09-28 | 广东电网有限责任公司 | A kind of 10kV line protective devices do not have a power failure periodical inspection method |
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