CN110687386A - Three-phase inconsistent protection test box for circuit breaker body - Google Patents
Three-phase inconsistent protection test box for circuit breaker body Download PDFInfo
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- CN110687386A CN110687386A CN201911072059.0A CN201911072059A CN110687386A CN 110687386 A CN110687386 A CN 110687386A CN 201911072059 A CN201911072059 A CN 201911072059A CN 110687386 A CN110687386 A CN 110687386A
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
The invention discloses a three-phase inconsistent protection test box of a breaker body, which relates to the field of relay protection acceptance and regular inspection work of a power system, wherein three liquid crystal display timers are arranged in a box body, the display parts of the three liquid crystal display timers are embedded into a panel to display outwards, each liquid crystal display timer comprises a pair of power supply contacts, a pair of meter starting contacts and a pair of meter stopping contacts, three pairs of meter starting jacks and three pairs of meter stopping jacks are arranged on the panel, each pair of meter starting jacks is correspondingly connected with one pair of meter starting contacts, and each pair of meter stopping jacks is correspondingly connected with one pair of meter stopping contacts; the panel is also provided with four jacks of THG, THA, THB and THC and three buttons of STA, STB and STC, the interior of the THG jack is connected with the same end of the three buttons, and the interiors of the three jacks of THA, THB and THC are respectively connected with the other ends corresponding to the three button switches of STA, STB and STC; the panel is also provided with a power switch and a grounding jack of the test box shell, and the power supply is supplied by alternating current 220V. The invention improves the protection and regular inspection efficiency, shortens the power failure maintenance time and enhances the operation reliability of the power grid.
Description
Technical Field
The invention relates to the field of relay protection acceptance and scheduled inspection work of a power system, in particular to a three-phase inconsistent protection test box for a circuit breaker body, which is suitable for performing scheduled inspection test on three-phase inconsistent protection of the circuit breaker body.
Background
In an electric power system, switches of 220kV and above voltage classes are generally provided with circuit breakers operated in a split-phase mode, in order to prevent the misoperation or the operation rejection accidents of the circuit breakers caused by the inconsistent three-phase positions of the circuit breakers, namely, the three phases can break one phase or two phases to cause the misoperation or the operation rejection accidents of the circuit breakers, the three-phase inconsistent protection is adopted for the circuit breakers, according to the technical regulation of relay protection and safety automatic devices of GB/T14258 + 2006, the three phases of the circuit breakers of 220 ~ 500kV are inconsistent, the three-phase inconsistent protection of a body of the circuit breakers is to be protected as far as possible by adopting the three-phase inconsistent protection of the body of the circuit breakers, the three-phase inconsistent protection of the body of the circuit breakers is to connect normally open auxiliary contacts and normally closed of A, B, C three-phase switches in parallel and then in series, and then to start a time relay, when the three-phase positions of the circuit breakers are inconsistent, the intermediate relay is actuated by time delay, and the three-phase circuit breakers are tripped, and the 220 kV.
With the continuous rising of the load level of a power grid, the load current of a power transmission line with the voltage class of 220kV or above is also continuously increased, so that when the line is in non-full-phase operation, override tripping can be caused if the line is not quickly cut off, and the non-full-phase operation can cause great damage to large equipment such as a generator, and the constant detection of three-phase inconsistent protection of a circuit breaker is very important. As the inconsistent protection of the circuit breaker body is realized as long as the three-phase position of the switch is inconsistent, the time relay outlet is started to trip, and no locking condition exists, the time relay is required to operate reliably. The three-phase inconsistent protection action time of the 220kV circuit breaker body is generally set to be 2s, the main transformer is generally set to be 1.5s, and whether the time is qualified or not is checked through tests.
At present, in an actual fixed-inspection test, because a special formed three-phase inconsistent protection test device for a circuit breaker body is not provided, a worker generally uses a single-strand short-circuit method at a circuit breaker terminal box to cause one-phase tripping of the circuit breaker, so that the three-phase inconsistent protection action is exported, and then judges whether time delay is correct or not through a signal on a monitoring system, so that firstly, the fixed-inspection efficiency is very low, because the monitoring system has a lot of information and is difficult to display time clearly, the corresponding switch position information is generally found to be obtained by calculating the time difference; and secondly, the working personnel use the single strand wire to short-circuit the tripping positive and negative power supplies of one phase of switch, so that the direct current grounding or short circuit is easy to occur, and even the electric shock accidents of the personnel are easy to occur. Based on this, it is necessary to develop a tool to carry out the scheduled inspection test for the inconsistent protection of circuit breaker body three-phase, can improve protection scheduled inspection efficiency like this, shorten the power failure repair time, reinforcing electric wire netting operational reliability, can reduce the emergence of staff's electric shock accident simultaneously.
Disclosure of Invention
The invention provides a three-phase inconsistent protection test box for a circuit breaker body, aiming at solving the problems that the three-phase inconsistent protection of the circuit breaker body is subjected to a scheduled inspection test so as to improve the protection scheduled inspection efficiency and reduce the occurrence of electric shock accidents of workers.
The invention is realized by the following technical scheme: a three-phase inconsistent protection test box for a circuit breaker body comprises a box body, wherein three liquid crystal display timers are arranged in the box body and are respectively marked as TXA, TXB and TXC, display parts of the three liquid crystal display timers are embedded into a panel to be displayed externally, each liquid crystal display timer comprises a pair of power supply contacts, a pair of meter starting contacts and a pair of meter stopping contacts, three pairs of meter starting jacks and three pairs of meter stopping jacks are arranged on the panel, each pair of meter starting jacks corresponds to one pair of meter starting contacts of one liquid crystal display timer, each pair of meter stopping jacks corresponds to one pair of meter stopping contacts of one liquid crystal display timer, the lower end of the inside of each meter starting jack is connected with the corresponding meter starting contact, and the lower end of the inside of each meter stopping jack is connected with the corresponding meter stopping contact; the panel is also provided with four jacks of THG, THA, THB and THC and three buttons of STA, STB and STC, wherein the interior of the THG jack is connected with one ends of three button switches of STA, STB and STC, and the interiors of the three jacks of THA, THB and THC are respectively connected with the other ends corresponding to the three button switches of STA, STB and STC; and the panel is also provided with a power switch and a test box shell grounding jack, and the power switch and the test box shell grounding jack are powered by alternating current 220V.
The invention provides a three-phase inconsistent protection test box for a circuit breaker body, which has the following principle: three liquid crystal display timers (TXA, TXB and TXC) are adopted to respectively test the three-phase inconsistent protection action outlet time when a three-phase switch of a breaker A, B, C trips, three small button switches (STA, STB and STC) are respectively connected in series to a tripping (closing) loop of a three-phase switch of a breaker A, B, C, the TXA, TXB and TXC respectively correspond to A, B, C three phases, display parts of the three liquid crystal display timers are embedded into a panel to display the time, generally, the rear part of each liquid crystal display timer comprises a pair of power contacts, a pair of meter starting contacts and a pair of meter stopping contacts, three pairs of meter starting jacks and three pairs of meter stopping jacks are arranged on the panel, each pair of meter starting jacks corresponds to one pair of meter starting contacts of the liquid crystal display timer, each pair of meter stopping jacks corresponds to one pair of meter stopping contacts of the liquid crystal display timer, the lower end inside each meter starting jack is connected with the corresponding meter starting contacts, the lower end in each meter stopping jack is connected with a corresponding meter stopping contact, each pair of meter starting jacks and meter stopping jacks are used for plugging a test wire, and the other end of each pair of meter starting jacks and meter stopping jacks is connected with an auxiliary contact of a circuit breaker; the panel is also provided with four jacks of THG, THA, THB and THC and three buttons of STA, STB and STC, the interior of the THG jack is connected with one end of three button switches of STA, STB and STC, namely the THG is a common end, the interiors of the three jacks of THA, THB and THC are respectively connected with the other ends corresponding to the three button switches of STA, STB and STC, the four jacks of THG, THA, THB and THC are used for inserting test wires during testing, and the other ends of the test wires are respectively connected with the positive/negative ends of the three-phase tripping circuit; the three button switches of STA, STB, STC are used for making each phase trip, still are equipped with switch and proof box shell ground connection jack on the panel, adopt and exchange 220V power supply. Taking the example that three phases of the circuit breaker are all closed, the auxiliary contact of the circuit breaker is CBJ-A, CBJ-B, CBJ-C in a dashed line frame in a graph of FIG. 4, and after the A-phase switch is tripped, two phases of B, C are tripped through the inconsistent protection action outlet of the three phases of the circuit breaker body, the invention has the following specific operations: one end of each of 2 test wires is respectively inserted into the THG common end and the THA jump A phase jack, and the other end of each test wire is respectively connected to the positive end and the negative end of the A phase trip loop, so that the small button switch STA is connected into the A phase trip loop to be used for pressing the STA button and tripping the A phase switch; then, the normally closed auxiliary contact CBJ-A of the A-phase breaker is respectively connected into the watch-playing jacks of the timers TXB and TXC through 2 test lines, and the functions are that the TXB and the TXC start to time after the A-phase switch trips; the normally closed auxiliary contact CBJ-B, CBJ-C of the B, C-phase breaker is respectively connected to the stop watch jacks of the timers TXB and TXC by using a test wire, and the TXB and TXC are used for ending the timing after the B, C-phase switch trips, so that the three-phase inconsistent protection action exit time of the breaker body is displayed. In addition, simulating a B-phase trip, and leading the three-phase inconsistent protection action to exit A, C two phases; simulating C-phase tripping, and leading the three-phase inconsistent protection action to jump A, B two phases; simulating AB two-phase tripping, three-phase inconsistent protection action outlet tripping C phase, BC two-phase tripping and AC two-phase tripping; and when the circuit breaker is switched on, only one phase or two phases can be switched on successfully, and then the circuit breaker is tripped through a three-phase inconsistent protection action outlet, and the test method is the same.
Compared with the prior art, the invention has the following beneficial effects: when the test box is used for carrying out the regular inspection test on the three-phase inconsistent protection of the circuit breaker body, whether the three-phase inconsistent protection action of the circuit breaker body is correct or not and whether the action export time is qualified or not can be visually and clearly displayed, so that the protection regular inspection efficiency can be improved, the power failure maintenance time can be shortened, and the operation reliability of a power grid can be enhanced.
Drawings
FIG. 1 is a schematic view of the arrangement of the panels of the test chamber of the present invention.
FIG. 2 is a schematic diagram of the power supply of the LCD timer according to the present invention.
Fig. 3 is a schematic diagram of electrical connection of a three-phase tripping switch of the circuit breaker A, B, C according to the present invention.
Fig. 4 is a schematic diagram of the electrical connection between the start watch and the stop watch of the timer (taking the switch on position, the hand jump a phase, and the protection jump B, C phase as examples).
The figures are labeled as follows: the test box comprises a test box power jack and a small switch, a test box shell grounding jack, a circuit breaker A, B, C three-phase tripping and closing button, a 4-A, B, C three-phase liquid crystal display timer, a 5-timer stopping jack, a 6-timer starting jack and a 7-circuit breaker A, B, C three-phase tripping and closing jack.
Detailed Description
The present invention is further illustrated by the following specific examples.
A three-phase inconsistent protection test box of a breaker body is disclosed, a panel is shown in figure 1, and electrical connections are shown in figures 2 and 3: the liquid crystal display timing device comprises a box body, wherein three liquid crystal display timers are arranged in the box body and are respectively marked as TXA, TXB and TXC, display parts of the three liquid crystal display timers are embedded into a panel to be displayed outwards, each liquid crystal display timer comprises a pair of power contacts, a pair of meter starting contacts and a pair of meter stopping contacts, three pairs of meter starting jacks and three pairs of meter stopping jacks are arranged on the panel, each pair of meter starting jacks corresponds to one pair of meter starting contacts of one liquid crystal display timer, each pair of meter stopping jacks corresponds to one pair of meter stopping contacts of one liquid crystal display timer, the lower end of the inside of each meter starting jack is connected with the corresponding meter starting contact, and the lower end of the inside of each meter stopping jack is connected with the corresponding meter stopping; the panel is also provided with four jacks of THG, THA, THB and THC and three buttons of STA, STB and STC, wherein the interior of the THG jack is connected with one ends of three button switches of STA, STB and STC, and the interiors of the three jacks of THA, THB and THC are respectively connected with the other ends corresponding to the three button switches of STA, STB and STC; and the panel is also provided with a power switch and a test box shell grounding jack, and the power switch and the test box shell grounding jack are powered by alternating current 220V.
Taking the example that three phases of the circuit breaker are all closed, the auxiliary contact of the circuit breaker is CBJ-A, CBJ-B, CBJ-C in a dashed line frame in a graph of FIG. 4, and after the A-phase switch is tripped, two phases of B, C are tripped through the inconsistent protection action outlet of the three phases of the circuit breaker body, the invention has the following specific operations: one end of each of 2 test wires is respectively inserted into the THG common end and the THA jump A phase jack, and the other end of each test wire is respectively connected to the positive end and the negative end of the A phase trip loop, so that the small button switch STA is connected into the A phase trip loop to be used for pressing the STA button and tripping the A phase switch; then, the normally closed auxiliary contact CBJ-A of the A-phase breaker is respectively connected into the watch-playing jacks of the timers TXB and TXC through 2 test lines, and the functions are that the TXB and the TXC start to time after the A-phase switch trips; the normally closed auxiliary contact CBJ-B, CBJ-C of the B, C-phase breaker is respectively connected to the stop watch jacks of the timers TXB and TXC by using a test wire, and the TXB and TXC are used for ending the timing after the B, C-phase switch trips, so that the three-phase inconsistent protection action exit time of the breaker body is displayed. The electrical connection schematic diagram of the test box is shown in fig. 3 and 4, in addition, the tripping of the phase B is simulated, and the two phases of the three-phase inconsistent protection action are tripped A, C; simulating C-phase tripping, and leading the three-phase inconsistent protection action to jump A, B two phases; simulating AB two-phase tripping, three-phase inconsistent protection action outlet tripping C phase, BC two-phase tripping and AC two-phase tripping; and when the circuit breaker is switched on, only one phase or two phases can be switched on successfully, and then the circuit breaker is tripped through a three-phase inconsistent protection action outlet, and the test method is the same.
The scope of the invention is not limited to the above embodiments, and various modifications and changes may be made by those skilled in the art, and any modifications, improvements and equivalents within the spirit and principle of the invention should be included in the scope of the invention.
Claims (1)
1. The utility model provides a inconsistent protection test case of circuit breaker body three-phase which characterized in that: the liquid crystal display timing device comprises a box body, wherein three liquid crystal display timers are arranged in the box body and are respectively marked as TXA, TXB and TXC, display parts of the three liquid crystal display timers are embedded into a panel to be displayed outwards, each liquid crystal display timer comprises a pair of power contacts, a pair of meter starting contacts and a pair of meter stopping contacts, three pairs of meter starting jacks and three pairs of meter stopping jacks are arranged on the panel, each pair of meter starting jacks corresponds to one pair of meter starting contacts of one liquid crystal display timer, each pair of meter stopping jacks corresponds to one pair of meter stopping contacts of one liquid crystal display timer, the lower end of the inside of each meter starting jack is connected with the corresponding meter starting contact, and the lower end of the inside of each meter stopping jack is connected with the corresponding meter stopping; the panel is also provided with four jacks of THG, THA, THB and THC and three buttons of STA, STB and STC, wherein the interior of the THG jack is connected with one ends of three button switches of STA, STB and STC, and the interiors of the three jacks of THA, THB and THC are respectively connected with the other ends corresponding to the three button switches of STA, STB and STC; and the panel is also provided with a power switch and a test box shell grounding jack, and the power switch and the test box shell grounding jack are powered by alternating current 220V.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911072059.0A CN110687386B (en) | 2019-11-05 | 2019-11-05 | Three-phase inconsistent protection test box for circuit breaker body |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911072059.0A CN110687386B (en) | 2019-11-05 | 2019-11-05 | Three-phase inconsistent protection test box for circuit breaker body |
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| CN110687386A true CN110687386A (en) | 2020-01-14 |
| CN110687386B CN110687386B (en) | 2022-04-19 |
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