Suspension insulator is widely used in the insulation and mechanical fixation of high voltage overhead transmission lines. And suspension insulator can be divided into disc suspension insulator and rod suspension insulator. Disc suspension insulator is the most widely used insulator in transmission line. Rod suspension insulator has been widely used in Germany and other countries.
When the voltage is higher than 33kV, the performance of pin insulator will decrease due to the increasing size and weight. At the same time, the handling and replacement of single insulator with larger size also bring great challenges to the actual operation. In order to solve these problems, suspension insulator came into being.
Suspension insulator is widely used in the insulation and mechanical fixation of high voltage overhead transmission lines. And suspension insulator can be divided into disc suspension insulator and rod suspension insulator. Disc suspension insulator is the most widely used insulator in transmission line. Rod suspension insulator has been widely used in Germany and other countries.
The suspension insulator is composed of several porcelain discs which are connected in series in the form of strings through metal chain links. The wire is fixed on the bottom insulator, while the insulator on the top is fixed on the cross arm of electric tower. Single insulator porcelain disc can be applied to low-voltage lines, while multiple insulator porcelain discs in series can be applied to higher voltage. For example, six 11 kV insulator porcelain discs in series can be applied to 66 kV transmission and distribution lines.
Advantages of suspension insulator:
1) On the basis of that the rated voltage of each porcelain disc is 11kv (the higher rated voltage is 15kV), suspension insulators string can be applied to any voltage level by using different number of discs insulator.
2) When any disc insulator in the suspension insulator string is damaged, the maintenance workers can quickly replace the damaged insulator.
3) Because the wire is suspended on the flexible suspension insulator string, the mechanical stress on each insulator is smaller.
4) Since the wire is carried by the bottom insulator, the height of the conductor position is always less than the total height of the supporting structure. Therefore, the conductor is safer.
Disadvantages of suspension insulator:
1) The price of suspension insulator string is higher than that of pin insulator.
2) Compared with pin insulator or post insulator, suspension insulator string needs higher support space to ensure the current conductor is far away from the ground.
3) In suspension insulator system, the free swing amplitude of wire is large, so there should be a large space between wires.
