CN214380077U - Extremely fast zero-loss degree of depth current limiting device - Google Patents

Abstract

The utility model relates to a very fast zero loss degree of depth current limiting device, include first transformer and the second transformer that is connected with the live wire, be connected through the very fast zero loss degree of depth current limiting device between first transformer and the second transformer, a serial communication port, the very fast zero loss degree of depth current limiting device includes the current sensor who is connected with the electric wire netting generating line, the current sensor output is established ties and is had quick transverter and broad width current limiting reactor after parallelly connected and carry out ground protection, just the current sensor output other end is connected with station control layer monitoring center through the observing and controlling unit electricity that has current transformer, station control layer monitoring center output data connection has local computer, realize the data connection transmission through LAN or wireless network between this body computer and the remote computer. Has the advantages that: the utility model discloses both solved the short circuit capacity problem, saved again because of the investment that needs change bigger breaking capacity switchgear.

Description

Extremely fast zero-loss degree of depth current limiting device

Technical Field

The utility model relates to an electric power protection device technical field, concretely relates to extremely fast zero loss degree of depth current limiting device.

Background

The grade of the short-circuit current of the power system is continuously improved, and the value of the short-circuit current of the power grid is directly approaching the maximum allowable level. Therefore, the short-circuit current is bound to exceed the allowable value of primary system equipment, which is called as the phenomenon of exceeding the short-circuit current, so that the equipment is bound to be stable in movement and thermal stability, and the current main current limiting measures of the power grid are damaged because the equipment cannot bear the phenomenon of exceeding the standard: although a method of additionally installing a current-limiting reactor is generally adopted, although short-circuit current can be effectively inhibited, a large reactive power and active power loss are caused by long-term operation, the economic performance of a power grid is seriously influenced by a method of switching a current-limiting reactance type device by combining an explosive bridge body and a current-limiting fuse, and the following problems still exist in operation and maintenance:

the explosive bridge-current limiting fuse device needs to be powered off and replaced with expensive spare parts after each action, has long power-off time and high operation cost, saves electric energy, saves cost and can be compensated and returned

Secondly, the purchase, use, storage and transportation of the explosive assembled in the body cavity of the explosion bridge are strictly controlled by the state, and the replacement operation risk coefficient is high, so that the popularization and the application of the power grid are not facilitated.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a can effectively restrain the short-circuit current peak value sharply rising of newly-built system or current system dilatation, the short-circuit current maximum value that actually flows through is far below anticipated peak value, has both solved the short-circuit capacity problem, has saved again because of the very fast zero loss degree of depth current limiting device of the investment of more break-make ability switchgear that needs to be changed, is realized through following scheme.

In order to realize the above purpose, the utility model discloses a technical scheme be: the utility model provides a very fast zero loss degree of depth current limiting device, includes first transformer and the second transformer that is connected with the live wire, be connected through very fast zero loss degree of depth current limiting device between first transformer and the second transformer, very fast zero loss degree of depth current limiting device includes the current sensor who is connected with the electric wire netting generating line, the current sensor output is established ties and is had quick transverter and broad width current limiting reactor after parallelly connected and carry out ground protection, just the current sensor output other end is connected with station control layer monitoring center through the observing and controlling unit electricity that has current transformer, station control layer monitoring center output data connection has local computer, realize the data connection transmission through LAN or wireless network between local computer and the remote computer, just station control layer monitoring center output is equipped with the alarm that is connected with local computer, alarm, A temperature meter and an irradiator.

Furthermore, the quick converter is driven by a turbine and comprises a transmission connecting rod and a transmission assembly kept by a disc spring group, and repulsive force generated by the turbine is transmitted to an insulating pull rod connected with a moving end contact according to the proportion of the holding force required by the vacuum arc-extinguishing chamber through a transmission connecting lever.

Furthermore, observe and control unit fixed mounting and organize the cabinet alone on the instrument room door on the main cabinet body, and observe and control unit and go up to be connected with rather than the demonstration accuse end of looks adaptation.

Furthermore, the current transformer is a low-impedance shielding layer isolation electronic coil between the primary winding and the secondary winding, and an iron core on the current transformer is a low-residual-magnetic-band air-gap iron core.

The technical effects of the utility model reside in that:

1. the impact of the bus short-circuit fault on the main transformer can be effectively reduced, and the bus short-circuit current can be effectively reduced;

2. when the bus has a short-circuit fault, the device measurement and control unit converts the detected fault signal into an instruction, and the instruction is sent to an execution mechanism of the special current converter to put the wide-width current-limiting reactor into operation, so that the bus short-circuit current is greatly reduced, and the damage to the transformer is reduced.

Drawings

FIG. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a schematic circuit diagram of the very fast zero loss deep current limiting device of the present invention;

fig. 3 is a schematic connection diagram of the station-level monitoring center of the present invention.

Reference numerals: 1-a first transformer; 2-a second transformer; 3-a top-speed zero-loss deep current limiting device; 4-a grid bus; 5-a current sensor; 6-a fast converter; 7-wide current limiting reactor; 8, a measurement and control unit; 9-station control layer monitoring center; 10-a local computer; 11-a remote computer; 12-an alarm; 13-a temperature meter; 14-irradiator.

Detailed Description

Referring to the attached figures 1-2, a very-speed zero-loss deep current limiting device comprises a first transformer 1 and a second transformer 2 connected with a live wire, wherein the first transformer 1 and the second transformer 2 are connected with each other through a very-speed zero-loss deep current limiting device 3, the very-speed zero-loss deep current limiting device 3 comprises a current sensor 5 connected with a power grid bus 4, the output end of the current sensor 5 is connected in series with a fast converter 6 and a wide current limiting reactor 7 which are connected in parallel and performs ground protection, the other output end of the current sensor 5 is electrically connected with a station control layer monitoring center 9 through a measurement and control unit 8 with a current transformer, the data connection of the output end of the station control layer monitoring center 9 is connected with a local computer 10, and the local computer 10 and a remote computer 11 realize data connection transmission through a local area network or a wireless network, and the output end of the station control layer monitoring center 9 is provided with an alarm 12, a temperature meter 13 and an irradiation meter 14 which are connected with a local computer 10.

The specific embodiment of the scheme is that the fast converter 6 is driven by a turbine, the fast converter 6 comprises a transmission connecting rod and a transmission assembly kept by a disc spring group, and repulsive force generated by the turbine is transmitted to an insulating pull rod connected with a moving end contact according to the proportion of the keeping force required by a vacuum arc-extinguishing chamber through a transmission connecting lever.

The specific embodiment of this scheme does, observe and control unit 8 fixed mounting is on the instrument room door on the main cabinet body and group cabinet alone, and observe and control unit and go up to be connected with rather than the demonstration accuse end of looks adaptation.

The specific embodiment of the scheme is that the current transformer is a low-impedance shielding layer isolation electronic coil between a primary winding and a secondary winding, and an iron core on the current transformer is a low-remanence iron core with an air gap.

The specific embodiment of the scheme is that when the system is in a normal state during normal operation, the fast converter 6 of the extremely-fast zero-loss deep current limiting device 3 is in a switching-on position, the converter bears the line working current, and the device is in a zero-impedance state and shows zero loss, no pressure drop and no magnetic field pollution;

when a short-circuit fault occurs in the system, the measurement and control unit of the measurement and control unit detects the instantaneous value and the current change rate of the system current in real time, and if and only if the instantaneous value and the current change rate both reach a setting value, the current converter is commanded to immediately act to open a brake, the device can quickly put a wide-width current-limiting reactor in l5ns and present a high-impedance state, the short-circuit current is limited in an expected value, and other conventional circuit breakers in the circuit are ensured to be reliable and have no short-circuit fault;

after the short-circuit fault is removed, if the measurement and control unit detects that the system current is smaller than a preset return current fixed value, the short-circuit fault is eliminated, the rapid current converter 6 is commanded to be switched on immediately, the wide current-limiting reactor 7 is bypassed within 15ms, the device is in a zero impedance state, the system can recover to operate in a normal lossless state, if the measurement and control unit detects that the system current does not reach the return current fixed value, the fact that the rapid current converter 6 is always in a switching-off state when the system short-circuit fault does not exist is shown, the rapid current converter enters a self-protection state within 2s, the rapid current converter 6 is commanded to be switched on, the function also serves as self-healing protection after the rapid zero-loss deep current limiting device 3 is switched off by mistake, and the device is fast in action speed and can switch off the short-circuit current within 10ms when the system is short-circuited.

The fast converter 6 in the device can realize three-phase three-mechanism split-phase control, ensures that each phase action is switched on and off at a critical zero crossing point by reasonably judging the contact time, ensures the arc burning time to be shortest, can greatly increase the switching allowance of the arc extinguish chamber, improves the short-circuit switching capacity, can easily reach the effective value of the short-circuit current of 80kA at the maximum, and can realize the synchronous action of a three-phase one-mechanism or three-mechanism according to the system requirement.

The wide-width current-limiting reactor in the device has good current-limiting effect, no current passes through, no energy loss and no voltage drop and no magnetic leakage field is generated when the wide-width current-limiting reactor normally operates. The short-circuit protection circuit is only put into operation when a short circuit occurs, the reactance value can limit the short-circuit current to be less than 50% of the expected short-circuit current value according to the system requirement, so that the short-circuit current is greatly reduced in the short-circuit process, the transformer is prevented from being impacted by huge short-circuit current, and the opening and closing capacity of a circuit breaker in the system is correspondingly reduced.

The specific embodiment of the scheme is that the fast converter 6 adopted by the scheme uses a simple and efficient transmission mechanism, has small mechanical abrasion, higher mechanical service life and reliability, has the brake-separating time of less than 3ms and high speed, adopts the integrally cast solid-sealed polar pole to ensure that the vacuum arc-extinguishing chamber is reliably protected, avoids the influence of mechanical impact, dust and moisture, has high brake-separating speed, ensures that the dynamic and static contacts of the vacuum arc-extinguishing chamber are quickly disconnected, is beneficial to extinguishing electric arc, has the arc-burning quantity of less than 10 percent of a common circuit breaker during the arc-burning period, greatly improves the breaking capacity, has small contact burning, increases the electrical service life of contacts in a series manner, has zero loss, does not generate heat and does not have pressure drop when a wide current-limiting reactor has no short circuit, has long service life and high reliability, is produced according to the highest quality requirement even under the strong electromagnetic interference environment, the converter can still operate reliably, and the self-diagnostic system of the fast converter avoids the functions of mistaken switching on and off and jump prevention. The electronic controller of the complete set of device has a real-time self-checking function, all function information can be monitored by sending a background alarm, the device has small action dispersion degree, basically no rebound when the device is switched on, the design of a core component transmission mechanism is simple, the switching-on time is short, the dispersion degree of the switching-on time and the switching-off time can be controlled within 0.2ms, a special disc spring is adopted to do work in the auxiliary work of the second half section of switching-on and switching-off, and finally, the movable and static contacts driven by the vortex disc are kept at the switching-on and switching-off positions, and meanwhile, the occurrence of the rebound when the device is switched on is also avoided.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the principles of the present invention may be applied to any other embodiment without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (4)

1. The utility model provides a very fast zero loss degree of depth current limiting device, includes first transformer (1) and second transformer (2) that are connected with the live wire, be connected through very fast zero loss degree of depth current limiting device (3) between first transformer (1) and second transformer (2), its characterized in that, very fast zero loss degree of depth current limiting device (3) are including current sensor (5) that are connected with electric wire netting generating line (4), current sensor (5) output is established ties and is had quick transverter (6) and broad width current limiting reactor (7) and carry out ground protection after parallelly connected, just current sensor (5) output other end is connected with station control layer surveillance center (9) through observing and controlling unit (8) electricity that have current transformer, station control layer surveillance center (9) output data connection has local computer (10), realize data through LAN or wireless network between local computer (10) and remote computer (11) And the station control layer monitoring center (9) is connected and transmitted, and an alarm (12), a temperature meter (13) and an irradiation meter (14) which are connected with a local computer (10) are arranged at the output end of the station control layer monitoring center.

2. The device according to claim 1, wherein the fast inverter (6) is driven by a turbine, and the fast inverter (6) comprises a transmission assembly which is kept and held by a transmission connecting rod and a disc spring set, and the repulsive force generated by the turbine is transmitted to an insulating pull rod connected with a moving end contact according to the proportion of the holding force required by a vacuum arc-extinguishing chamber through a transmission connecting lever.

3. The device according to claim 1, wherein the measurement and control unit (8) is fixedly mounted on an instrument room door on the main cabinet body and is independently assembled into a cabinet, and the measurement and control unit is connected with a display and control end matched with the measurement and control unit.

4. The device of claim 1, wherein the current transformer is a low impedance shielding layer between the primary and secondary windings to isolate the electronic coil, and the core of the current transformer is a low remanence air gap core.

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