Abstract
Lightning surge and switching surge can be suppressed with an arrester. Generally, it is effective to install the arrester at the open end of the bus or the transmission line, and the overvoltage value can be calculated by using a digital computer or a TNA. But we can not know the value before the computation is done.
This paper gives a simple formula with which we can know easily the overvoltage value on the line with the arrester installed at the open end.
By the way, lightning surge in a substation becomes lower by using the arrester with more reduced residual voltage. But it must deal with more energy of switching surges. So, reducing the residual voltage has its limits. Also, even if the arrester is used, it happens to exceed the desired overvoltage value when the bus circuit is long.
This paper also shows that the lightning surge can be suppressed well by installing a supplemental arrester at the open end of the bus, even if it is a light-duty arrester. The overvoltage value is shown by using the formula developed in the paper.
