Thermal shrinkage materials used in substation comprehensive insulation protection can reduce the occurrence of accidents, improve the reliability of power supply system, the safe operation of power system is of great significance. So what problems should the substation implement insulation protection to pay attention to?

Precautions for insulation protection of substation:

(1) Different heat shrinkage materials are selected according to different power transformation facilities.

For Bare Masterbatch, the parent row insulating casing (MPG) can be selected, and the composite insulated heat shrinkable Belt (FJRD) may also be wound. The former must disassemble the master row, construction is difficult, the time required is long, but after treatment beautiful, high gloss, the latter do not have to disassemble the mother row, construction is easier, short time. Users can choose according to the actual situation. If the new substation is not shipped, the time is generous can be used MPG way, the old station transformation power outage time is limited may consider the use of FJRD way.

An insulating joint protective box may be used at the junction of the parent row or at the junction with the casing (e.g. wall casing, main variable low pressure side casing). Because the joint junction often needs to be unloaded, the use of insulation protective box can be flexibly opened, closed, easy to repair, do not use insulated casing or hot shrinkage to fix death. Users must contact the manufacturer in advance, according to the situation in the field prefabricated various shapes of insulation protection connector box (type I, J type, T type, etc.).

Thermal shrinkage Belt (FJRD) should be used to carry out insulation treatment for special, non-often disassembled charged bodies.

(2) About heating treatment

Insulation casing or heat shrinkable belt can only shrink to the surface of the charged body by heating treatment, therefore, the heating treatment process is not only related to the life of the material, but also related to safety. Heating treatment should pay attention to the following points: ① appearance heating should be smooth and uniform, shrinkage after the wall thickness does not exceed 3mm below. ② Thermal Shrinkage Whether the use of casing or heat shrinkage belt, should ensure that the shrinkage in place, the middle does not residual air gap, otherwise it will lead to heat impact life, especially the corner should be carefully handled to ensure that in place. ③ coupling treatment of heat shrinkable casing (length 1m) or thermal shrinkage belt connection is very important, the heating time at the junction must be long enough to ensure its thermal shrinkage and smooth transition, so as to ensure that the front and rear two sections and the electrical performance of the junction is consistent.

(3) Residual mother row Live experience electrical position

The bus and the front and rear of the switch must be set aside for the electrical inspection grounding position, in order to repair the electrical grounding. The electrical inspection position of ABC Three-phase must be selected according to the actual field. A, B, C three-phase position should be triangular, should not be a glyph, in order to increase the distance of three-phase bare charged body to prevent small animals short circuit, in addition, should be as far away from supporting insulators as possible, to prevent the charged body to the porcelain bottle flashover, see Figure 1.

(4) About climbing distance growth device

When supporting porcelain bottle to add anti-fouling and climbing skirt, it is necessary to first carry out strict and meticulous cleaning of the porcelain bottle, and then add the crawl growth device, as shown in Figure 2, at A Place with 502 glue adhesive, the treatment of the junction will directly affect the use of the effect. Ideally, the junction should be flat and smooth, with no bumps. If the joint is not smooth, long time wind and rain will be residual dust around it, so not only did not increase the crawl distance, but increased the hidden danger of dirt, therefore, the construction must be strictly checked.

(5) Other precautions

For the implementation of thermal shrinkage insulation protection of the substation facilities, in addition to the power inspection, other charged body exposed parts should be fully protected with heat shrinkable casing or heat shrinkable belt, can not leave a dead angle. If the main variable low pressure casing is not protected by insulation, the recent use of special-shaped protective box for insulation protection, effectively prevent small animals to cause the main to close short circuit. In addition, the disassembly of the mother row for insulation protection, the restoration of the original wiring method must ensure that the junction is fixed and firm, to prevent the bolt is not tight caused by the heating at the junction.

Of course, we can not adhere to the rut, in addition to the above need to pay attention to We also see the substation insulation protection of the specific situation analysis and treatment.

变电站实施绝缘防护应注意的问题

热缩材料用于变电站的综合绝缘防护可减少意外事故的发生，提高供电系统的可靠性，对电力系统的安全运行具有重要意义。那么变电站实施绝缘防护应注意哪些问题呢？

变电站绝缘防护注意事项：

（1）根据不同的变电设施选用不同的热缩材料。

对裸露母排，可选用母排绝缘套管（MPG），也可用复合绝缘热缩带（FJRD）缠绕。前者必须拆卸母排，施工难度较大，所需时间长，但处理后美观、光泽度高；后者不必拆母排，施工较容易，时间短。用户可根据实际情况选用。如新建变电站未投运、时间宽裕可采用MPG方式，老站改造停电时间有限可考虑采用FJRD方式。

母排接头处或与套管连接处（如穿墙套管、主变低压侧套管）可采用绝缘接头防护盒。由于接头联结处常常需要卸装，采用绝缘防护盒可灵活打开、合上，便于检修，不要用绝缘套管或热缩带固定死。用户须事先与厂商联系，根据现场状况预制各种形状的绝缘防护接头盒（I型、J型、T型等）。

对外型特殊、不经常拆卸的带电体应采用热缩带（FJRD）实施绝缘处理。

（2）关于加热处理

绝缘套管或热缩带只有通过加热处理才能收缩于带电体表面，因此，加热处理工艺不仅关系到材料的寿命，而且关系到安全性。加热处理应注意以下几点：①外观　加热后应光滑均匀，收缩后壁厚不超过3mm以下。②热收缩性　无论采用套管还是热缩带，均应保证收缩到位，中间不残留气隙，否则会导致发热影响寿命，尤其是弯角处应仔细处理才能保证到位。③联结处理　热缩套管（长1m）或热缩带连接处的处理至关重要，联结处加热时间必须足够长才能保证其热收缩性和平稳过渡，从而保证前后两段和联结处的电气性能一致。

（3）留余母排带电体验电位置

对母线以及开关前后母排必须留出验电接地位置，以便检修时验电接地用。必须根据现场实际选择ABC三相的验电位置。A、B、C三相位置应呈三角形，不应呈一字形，以增加三相裸露带电体的距离防止小动物短路；另外，应尽可能远离支持绝缘子，以防带电体对瓷瓶闪络，见图1。

（4）关于爬距增长器

对支持瓷瓶加装防污增爬裙时，必须首先对瓷瓶进行严格细致的清洁处理，然后加装爬距增长器，如图2所示，在A处用502胶粘上，联结处的处理将直接影响使用效果。理想情况应是联结处平整光滑，没有凹凸不平。如果联接处不平滑，长时间的风吹雨淋必将在其周围残留灰尘，这样不仅没有增加爬距，反而增加了污闪隐患，因此，施工中必须严格把关。

（5）其他注意事项

对于实施热缩绝缘防护的变电设施，除验电处外，其他带电体裸露部分应全部用热缩套管或热缩带进行防护，不能留死角。如主变低压套管处以前未进行绝缘防护，最近采用异型防护盒进行绝缘防护，有效地防止了小动物引起主变近距离短路。另外，对拆卸母排进行绝缘防护的，恢复原接线方式后必须保证联结处固定牢固，以防因螺栓不紧而造成联结处发热。

当然我们不能墨守成规，除了以上需要注意的我们还要视变电站绝缘防护的具体情况分析处理。