Device for overvoltage control in live line working

Abstract

A new device for control of overvoltages during live work has been developed in Ukraine. The device provides improved limitation of overvoltages at the worksite in comparison with the traditional portable protective gap that has been in use for several decades. The new device consist of a rod air gap connected in series with a highly nonlinear ZnO resistor. The sparkover voltage of the device is 1.5 to 1.7 times the peak phase-to-earth maximum nominal system voltage. The new device has been tested extensively in the laboratory and is now undergoing in-service validation tests.