CN211181919U

CN211181919U - Lightning protection transformer

Info

Publication number: CN211181919U
Application number: CN202020095125.8U
Authority: CN
Inventors: 曾祥军; 陆绍斌; 潘健洪; 任锦焯; 冯杰华; 姚天洪
Original assignee: Orion Transformers & Electrics Co ltd
Current assignee: Orion Transformers & Electrics Co ltd
Priority date: 2020-01-16
Filing date: 2020-01-16
Publication date: 2020-08-04
Anticipated expiration: 2030-01-16

Abstract

The utility model discloses a lightning protection transformer, which comprises an oil tank, a transformer body, a high-voltage input sleeve, a low-voltage output sleeve and a lightning-inducing sleeve, wherein the transformer body is arranged in the oil tank, and is immersed in insulating oil, the high-voltage input sleeve, the low-voltage output sleeve and the lightning-inducing sleeve are arranged on the oil tank, the transformer body comprises an iron core, a low-voltage winding and a hedging winding, the hedging winding is arranged on one side of the iron core, the low-voltage winding is wound on the other side of the iron core, the hedging winding comprises a high-voltage winding and a lightning-inducing winding, the winding direction of the high-voltage winding is opposite to that of the lightning-induced winding, the high-voltage input sleeve is electrically connected with the high-voltage winding, the low-voltage output sleeve is electrically connected with the low-voltage winding, the lightning-leading sleeve is electrically connected with the lightning-leading winding, and the starting end of the hedging winding is provided with a shielding ring, and the shielding ring and the hedging winding are connected in parallel and then are grounded. The utility model discloses effectively prevent the transformer thunderbolt, improve product safety and reliability, prolong the transformer life-span, reduce and restore and the loss of shutting down.

Description

Lightning protection transformer

Technical Field

The utility model relates to a transformer technical field, in particular to lightning protection transformer.

Background

At present, a large number of small and medium-sized distribution transformers are installed in various outdoor environments, many domestic places are areas with active thunder and lightning, and some places count thunderstorm days every year and even can reach more than dozens of days. Transformers and other outdoor operated electrical equipment damaged by lightning strikes are numerous.

The small distribution transformers of conventional insulating construction have several disadvantages:

1. the self-healing protection structure is not available, and once the self-healing protection structure is impacted by overvoltage, the self-healing protection structure is permanently damaged; 2. after being impacted by overvoltage, the device can not be self-repaired, and the reliability of the device without 'robustness' is not high; 3. the additional losses such as the self destruction of the equipment and the power failure and shutdown of the power grid are huge, and the influence is wide.

At present, a transformer structure which can withstand lightning or overvoltage is a traditional structure developed based on the last century, a low-voltage inner winding is mostly designed into a ZIGZAG structure, and when the voltage is converted in a positive direction and a negative direction, impact waves can be offset in the winding to achieve the effects of lightning protection and impact resistance. The structure has the following defects: 1. the manufacturing process is complex, the consumption of materials such as electromagnetic wires is increased by about 12%, and the load loss of the transformer is correspondingly improved; 2. the transformer has limited manufacturing capacity, troublesome winding connection, insulation aging damage after receiving electricity and thermal shock, and the transformer can be used after being repaired.

Disclosure of Invention

The to-be-solved technical problem of the utility model is, to the not enough among the above-mentioned prior art, provide a lightning protection transformer, it effectively prevents the transformer thunderbolt, improves product safety and reliability, prolongs the transformer life-span, reduces to restore and the loss of shutting down.

In order to solve the technical problem, the technical scheme of the utility model is that:

a lightning protection transformer comprises an oil tank, a transformer body, a high-voltage input sleeve, a low-voltage output sleeve and a lightning triggering sleeve, wherein the transformer body is arranged in the oil tank, and is immersed in the insulating oil, the high-voltage input sleeve, the low-voltage output sleeve and the lightning-inducing sleeve are arranged on the oil tank, the transformer body comprises an iron core, a low-voltage winding and a hedging winding, the hedging winding is arranged on one side of the iron core, the low-voltage winding is wound on the other side of the iron core, the hedging winding comprises a high-voltage winding and a lightning-inducing winding, the winding direction of the high-voltage winding is opposite to that of the lightning-induced winding, the high-voltage input sleeve is electrically connected with the high-voltage winding, the low-voltage output sleeve is electrically connected with the low-voltage winding, the lightning-leading sleeve is electrically connected with the lightning-leading winding, and the starting end of the hedging winding is provided with a shielding ring, and the shielding ring and the hedging winding are connected in parallel and then are grounded.

Preferably, the shielding ring comprises a shielding ring body and a transient resistance curtain, and the transient resistance curtain is arranged inside the shielding ring body at intervals.

Preferably, the number of transient resistance curtains is 8-12.

As a preferable scheme, the shielding ring body includes a shielding foil layer and a heat-resistant layer, and the heat-resistant layer wraps the outer side of the shielding foil layer.

As a preferable scheme, corrugated sheets for heat dissipation are arranged on two sides of the oil tank.

As a preferable scheme, the lightning protection transformer further comprises a current leakage cable, and the shielding ring and the hedging winding are connected in parallel and then pass through a current leakage cable grounding wire.

Preferably, the current leakage cable includes a copper wire and a heat-resistant insulating layer, and the heat-resistant insulating layer is wrapped around the copper wire.

The utility model has the advantages that: the transformer can be prevented from being struck by lightning through the matching of the iron core, the opposed winding, the high-voltage input sleeve and the lightning-triggering sleeve, the safety and the reliability of a product are improved, the service life of the transformer is prolonged, and the repair and shutdown losses are reduced; because the winding direction of the high-voltage winding is opposite to that of the lightning attracting winding, the high-voltage winding and the lightning attracting winding can mutually impact to offset a magnetic field, so that the high-voltage winding and the lightning attracting winding are prevented from being broken down due to overvoltage generated by induction, the transformer is protected from being damaged by overvoltage, and the service life of the transformer is effectively prolonged; the earth connection after shield ring and counterpulsation winding are parallelly connected, and the shield ring is including shielding ring body and transient resistance curtain, under the produced overvoltage effect of thunderbolt, the resistance of transient resistance curtain is the low value, the produced electric current of thunderbolt just can flow into the ground through the counterpulsation winding, so just can be with the voltage control on the counterpulsation winding in the safety range to the safety of protection transformer, and after the voltage that is higher than transient voltage disappears, the high resistance state just can be recovered to the transient resistance curtain, even this transformer has the self-healing function.

Drawings

FIG. 1 is a schematic view of an assembly structure according to an embodiment of the present invention;

fig. 2 is a schematic structural view of the opposed winding and the iron core of the present invention;

FIG. 3 is a schematic view of the shielding ring of the present invention;

FIG. 4 is a schematic diagram of the direction of the magnetic force generated by the high-voltage winding of the present invention;

fig. 5 is a schematic view showing the direction of the magnetic force generated by the lightning strike winding according to the present invention.

In the figure: 1-oil tank, 2-high voltage input sleeve, 3-lightning-leading sleeve, 4-low voltage output sleeve, 5-iron core, 6-high voltage winding, 7-lightning-leading winding, 8-shielding ring body, 9-transient resistance curtain, 10-shielding foil layer, 11-heat-resistant layer, 12-corrugated sheet and 13-current leakage cable.

Detailed Description

The structure and operation of the present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 1 to 3, a lightning protection transformer comprises an oil tank 1, a transformer body, a high voltage input sleeve 2, a low voltage output sleeve 4 and a lightning triggering sleeve 3, wherein the transformer body is arranged in the oil tank 1 and immersed in insulating oil, the high voltage input sleeve 2, the low voltage output sleeve 4 and the lightning triggering sleeve 3 are arranged on the oil tank 1, the transformer body comprises an iron core 5, a low voltage winding and a hedging winding, the hedging winding is arranged on one side of the iron core 5, the low voltage winding is wound on the other side of the iron core 5, the hedging winding comprises a high voltage winding 6 and a lightning triggering winding 7, the winding direction of the high voltage winding 6 is opposite to that of the lightning triggering winding 7, the high voltage input sleeve 2 is electrically connected with the high voltage winding 6, the low voltage output sleeve 4 is electrically connected with the low voltage winding, the lightning triggering sleeve 3 is electrically connected with the lightning triggering winding 7, and the winding end of the hedging winding is provided, and the shielding ring and the hedging winding are connected in parallel and then are grounded.

Preferably, the shielding ring comprises a shielding ring body 8 and a transient resistance curtain 9, and the transient resistance curtain 9 is arranged inside the shielding ring body 8 at intervals.

Preferably, the number of transient resistive curtains 9 is 8-12.

As a preferred scheme, the shielding ring body 8 includes a shielding foil layer 10 and a heat-resistant layer 11, and the heat-resistant layer 11 is wrapped on the outer side of the shielding foil layer 10, so that electromagnetic induction interference of higher harmonics to a low-voltage winding can be blocked, and simultaneously, most of instantaneous heating of current can be isolated to conduct heat radiation to an offset winding, so that the transformer is protected from being damaged, and the service life of the transformer is prolonged.

As a preferable scheme, the corrugated sheets 12 for heat dissipation are arranged on both sides of the oil tank 1, so that the heat dissipation effect can be improved, the phenomenon that the transformer is damaged due to overheating can be effectively avoided, and the service life of the transformer is prolonged.

As a preferable scheme, the lightning protection transformer further comprises a current leakage cable 13, and the shielding ring and the hedging winding are connected in parallel and then pass through a current leakage cable grounding wire, so that a large current generated by lightning stroke can be quickly led into the ground through the current leakage cable 13, the damage of the large current to the transformer is effectively prevented, and the service life of the transformer is further prolonged.

As a preferable scheme, the current leakage cable 13 comprises a copper conductor and a heat-resistant insulating layer, and the heat-resistant insulating layer is wrapped on the outer side of the copper conductor, so that the heat-resistant insulating layer can isolate instant heating of current, quickly guide the current into the ground, protect the current leakage cable 13 from being damaged by electric and thermal breakdown, and further prolong the service life of the transformer.

As shown in fig. 4, the direction of the magnetic force line generated by the high-voltage winding 6 is shown in fig. 5, the direction of the magnetic force line generated by the lightning-induced winding 7 is shown in fig. 4 and fig. 5, it can be seen from fig. 5 that the direction of the magnetic force line generated by the high-voltage winding 6 is exactly opposite to the direction of the magnetic force line generated by the lightning-induced winding 7, and the high-voltage winding 6 and the lightning-induced winding 7 can mutually collide to cancel out a magnetic field, so that the breakdown caused by the overvoltage generated by induction between the high-voltage winding 6 and the lightning-induced winding 7 is avoided, the transformer is protected from being damaged by.

The transient resistance curtain 9 is a material with excellent nonlinear volt-ampere characteristics, and has the advantages of good response characteristics, no follow current, large through-current capacity, low residual voltage, strong overvoltage suppression capability and the like. The transient resistance value of the transient resistance curtain 9 is very large under normal working voltage (namely, smaller than the transient voltage), which is equivalent to an insulation state, and under the action of overvoltage generated by lightning stroke, the resistance of the transient resistance curtain 9 is low, so that current generated by the lightning stroke can flow into the ground through the oppositely-rushing winding, and the voltage on the oppositely-rushing winding can be controlled within a safety range, thereby protecting the safety of the transformer. When the voltage higher than the transient voltage disappears, the transient resistance curtain 9 can recover the high resistance state, even if the transformer has the self-healing function.

Compared with the common transformer, the material cost of the opposed winding is slightly increased by about 4-8%, and the direct benefits are as follows: compared with the conventional transformer, the transformer has stronger self-healing capability, effectively prevents the transformer from being struck by lightning, improves the safety and reliability of products, prolongs the service life of equipment, reduces the loss of repair and shutdown, can realize the win-win of manufacturers, users and power grid companies, and has more obvious economic and social benefits.

The above, only the utility model discloses preferred embodiment, all be according to the utility model discloses a technical scheme does any slight modification, the equivalent change and the modification to above embodiment, all belong to the utility model discloses technical scheme's within range.

Claims

1. A lightning protection transformer, its characterized in that: including oil tank, transformer body, high-pressure input sleeve, low pressure output sleeve and lightning-inducing sleeve, the transformer body is located in the oil tank to the submergence is in insulating oil, high pressure input sleeve, low pressure output sleeve and lightning-inducing sleeve locate on the oil tank, the transformer body includes iron core, low voltage winding and offset winding, one side of iron core is located to the offset winding, the low voltage winding is around the opposite side of locating the iron core, the offset winding includes high voltage winding and lightning-inducing winding, the winding of high voltage winding is opposite with the winding of lightning-inducing winding, high voltage input sleeve is connected with the high voltage winding electricity, low pressure output sleeve is connected with the low voltage winding electricity, lightning-inducing sleeve is connected with lightning-inducing winding electricity, the winding end of offset winding is equipped with the shielding ring, the ground wire after shielding ring and the offset winding are parallelly connected.

2. The lightning protection transformer of claim 1, wherein: the shielding ring comprises a shielding ring body and transient resistance curtains, and the transient resistance curtains are arranged inside the shielding ring body at intervals.

3. The lightning protection transformer of claim 2, wherein: the number of the transient resistance curtains is 8-12.

4. The lightning protection transformer of claim 2, wherein: the shielding ring body comprises a shielding foil layer and a heat-resistant layer, and the heat-resistant layer wraps the outer side of the shielding foil layer.

5. The lightning protection transformer of claim 1, wherein: and corrugated sheets for heat dissipation are arranged on two sides of the oil tank.

6. The lightning protection transformer of claim 1, wherein: the shielding ring and the hedging winding are connected in parallel and then pass through a current leakage cable grounding wire.

7. The lightning protection transformer of claim 6, wherein: the current leakage cable comprises a copper conductor and a heat-resistant insulating layer, wherein the heat-resistant insulating layer is wrapped on the outer side of the copper conductor.