Working Principle of Silicone Rain Booster Shed

Once a large-scale pollution flashover accident in power transmission and transformation equipment occurs, it will cause long-time power outages, urgent maintenance tasks, and large economic loss. In order to ensure safe operation of external insulation equipment of power transmission and transformation, the power department will take a variery of effective composite insulator technical measures to avoid pollution flashover accidents, such as sweeping every stop, live cleaning, water flushing, replacing insulators and so on. In this process, silicone ruuber shed for high voltage boosters, bushings, and insulators is used and its effect is very obvious.

Working Principle of Silicone Rubber Booster Shed

In the past, many power departments used super heated shrinkage silicone rain booster shed. During the installation, it was sleeved into the porcelain skirts from the top of the insulator and then heated by a blowtorch to make the silicone rain booster shed shrink by itself, and the inner diameter part was firmly clamped on the insulator porcelain skirts. 

According to relevant statistics, the incidence of pollution flashover after installing a rain booster shed has been an obvious downward trend, and the actual operation effect is really good. The fixed silicone ruuber shed for high voltage boosters, bushings, and insulators is made of rubber (the same material as the rain booster shed of synthetic insulators). It is made into an open rain booster shed by molding or cutting, which is sleeved on the edge of the porcelain rain booster shed. The fixed silicone rain booster shed is closely bonded with the porcelain skirt by adhesive (RTV silica gel) to form a composite insulation structure.

Antipollution Flashover Mechanism of Silicone Rain Booster Shed

Increase Creepage Distance

After the rain booster shed with a large diameter is sleeved on the porcelain skirt, the current situation of the external insulation of the original porcelain bottle is changed, the arc channel is prolonged, and the creepage distance is increased.

Limit Leakage Current

Under the condition of pollution flashover, the surface insulation resistance of porcelain decreases sharply. While, because the silicone rain booster shed has the characteristics of hydrophobicity, it still maintains a fairly high insulation resistance connected in series in the circuit. This high resistance plays a role in curbing the increase of leakage current to prevent pollution flashover.

Undertake The Working Voltage

Select appropriate numbers of silicone rain booster sheds and distribute them evenly on the porcelain. By doing this, when the porcelain performance falls evenly in the pollution flashover state, silicone ruuber shed for high voltage boosters, bushings, and insulators still maintains the original insulation strength. That's the reason why it can undertake a high distribution voltage and plays the main insulation role.

Avoid Short Rain Circuits And Air Gap

Because the diameter of silicone rubber booster shed is larger than that of the porcelain skirt, when it is washed by rains or water, it can block the rainwater flowing down the edge of the porcelain petticoat like an umbrella, so that the rainwater floats out and does not flow down the  porcelain skirt,. In this way, the silicone rubber booster shed can prevent the continuous downflow of excessive rainwater from short circuiting the air gap between the porcelain petticoat. In addition, to a certain extent, the booster shed also prevents the short circuit of birds and other small animals.