Lightning Protection of Electrical Substations - Thesis Example

The topics examined include the provision of air terminals, correctly sized down conductors and an effective earth system to conduct direct lighting strike currents safely to earth. In addition, the paper examines the recommendation in the standard to the use of co-ordinated surge protection devices with each piece of electrical and electronic equipment in the substation. The paper also includes the importance of maintaining lightning protection components for the 30-35 year expected life of a substation.

Two media headlines from the past two years dramatically illustrate the disruption that can be caused by lightning strikes on electrical substations. One incident is from the city of London in the UK and the other from a Southern California suburb in the US.On 19 April 2012, at about 5:30 pm, a lightning strike at the Wandsworth substation caused a voltage surge that damaged railway signalling equipment at two of London’s busiest stations, Victoria and Waterloo. This caused cancellations and long delays in train services inconveniencing thousands of homebound commuters.

Engineers worked through the night to restore normal services the following morning (BBC News).On 1 March 2014 at 02:30 AM, a lightning strike at the Harvey-Lynn substation in Riverside, California caused a fire and three sub-transmission lines went out of service affecting 21,000 customers including a hospital. Maintenance crews worked through the night to restore power to most consumers by 06:30 AM (CBS Los Angeles).. The chart below shows that the number of power outages affecting 50,000 or more customers in the US has increased from about 180 in the 2001 to 2005 period to over 250 outages in the 2006 to 2010 period (Amin).

A survey conducted by The National Lightning Safety Institute (NLSI) of the US in data compiled for the year 2008 says that 30% of all power outages in the US are lightning-related and cost over $ 1 billion annually (NLSI Report)