Critical Insight Into Performance Requirements and Test Methods for Surge Protective Devices Connected to Low-Voltage Power Systems

Surge protective devices, SPDs, improve the reliability of power systems by mitigating the risk of equipment failure due to impinging overvoltages. The role of SPDs is more challenging today when considering the advent of smart grids and the associated integration of sensitive electronic equipment into modern low-voltage power systems. This work provides critical insight into performance requirements and test methods for surge protective devices according to IEC 61643 and UL 1449 standards; SPD ratings and fail-safe behavior are on focus. Experimental arrangements are proposed to represent in a laboratory environment the surge current and/or temporary overvoltage events that SPDs may be exposed to in the field; experimental evidence, ATP-EMTP simulation results and field experience are used to support these proposals. Grey zones of SPDs performance and failure mode are discussed in the context of the integrated components technology.