Effectiveness of the Industry Standard Peninsula Technique for Grounding the Neutrals of Shunt Capacitors in High Voltage Substations

The industry standard IEEE C37.99-2000 implicitly recommends the use of peninsula grounding as the preferred method to ground the neutrals of capacitor banks in high voltage substations. The basis for this recommendation is a 1972 IEEE paper by Rogers and Gillies that has remained unchallenged until now. This paper compares the overall performance of a 735/230 kV substation grounding system designed according to the peninsula method and a more conventional design consisting of reasonably dense ground conductors in the 230 kV capacitor banks area and concludes that the conventional design offers superior performance both from a safety and EMI perspective. Although the analysis was conducted based on the full back-to-back capacitor switching transient current discharge, this paper focuses on the performance as computed based on the main resonant frequency due to the extent of the main results to be presented. A future paper will report the results of the transient analysis and will discuss resonance conditions that were observed at frequencies around 100 kHz