Understanding design, installation, and testing methods that promote substation IED resiliency for high-altitude electromagnetic pulse events

Recently, governments and concerned private entities have given considerable attention to high-altitude electromagnetic pulse (HEMP) events. Both groups are concerned that a HEMP event would have a serious social and economic impact on our society. However, to date, a limited amount of literature exists that focuses on HEMP events as they relate to substation intelligent electronic devices (IEDs). This paper demonstrates IED resiliency to HEMP events through analysis and test results. It presents substation grounding and wiring practices that are HEMP resilient and also highlights available HEMP standards as they relate to IEDs and substation control houses. This information will help utilities prevent unnecessary mitigation efforts and address the concerns regarding the effects of HEMP on substations and substation IEDs.