Experimental Research on Residual Voltage Characteristics of 10kV Entire Arrester Under 8/20 μs Impulse Current

Lightning arrester in distribution network is an important overvoltage protection device. The residual voltage characteristic under the lightning current impulse is an important parameter to describe the overvoltage protection capability of the arrester. Past research has often focused on the angle of ZnO resistors. The standard IEC is also to carry out test experiments from the view of ZnO resistors of the arrester. However, the lightning arrester passed the test still has a high damage rate. For the whole arrester operated for a period of time, there is no reliable research method to reflect its performance. For the entire arresters with unknown state, the lightning current residual voltage test and DC characteristic parameters test were designed to evaluate the arresters' performance from multiple angles. The results show that in the residual voltage test of the 10kV ZnO arresters of four manufacturers, the two manufacturers have passed the test, and the other two didn't meet the standards. The dynamic volt-ampere curves of four arresters during different lightning current shows the capability of limiting voltage of different arresters. The test of the DC characteristic parameters after the impulse of the whole arresters shows that as the lightning current increases, the DC parameters of the arrester decrease significantly. Finally, the instantaneous residual voltage ratio is defined to quantify the performance differences of the arresters under different lightning currents. It provides a tool for measuring the instantaneous performance of the arresters. The residual voltage ratio calculation results are consistent with the damage of the samples.