Annual Power Engineering Exchange (APEX) SUMMIT 2015

About APEX SUMMIT 2015 - Flyer

The Programme - Programme

About the Presenters - About the Presenters

APEX PAPER WINNER 2015

Gavin Austin, Mitton ElectroNet

Gavin is an Assistant Engineer, joining MEL after completing his engineering degree at the University of Canterbury in 2013. Since joining MEL Gavin has undertaken a range of studies, including arc flash studies, lightning studies, PSCAD modelling, earthing system modelling and earth grid testing.

Mitigating Earthing Hazards

Earthing systems are an essential element within a power system, providing reference voltage levels for the system, and paths for fault currents to flow.

Under fault conditions, large voltages may arise on the earthing system of a site, creating the potential for hazardous voltages to exist, both inside and outside of the site. Three categories of hazard exist: touch voltages, step voltages, and reach voltages. These hazards can be identified through earth grid modelling or earth grid injection testing.

Once hazards have been identified, there are often many mitigation options available, ranging from the cheap and simple to implement, to complex earthing schemes. Hazards can exist onto a wide range of equipment within the substation, and onto third party infrastructure, requiring a wide range of approaches to mitigation. Mitigation options include refurbishing the existing earth grid or infrastructure to remove the hazards or replacing the existing infrastructure with more suitable alternatives. Risk based analysis may also be used to determine whether mitigation is necessary.

Presentations