WHITEPAPER: A Comparative Study on Cost Savings Offered by Traveling Wave System Fault Locators over Traditional Distance Relays for Long Distance Transmission Lines

El Paso Electric (EPE) has experienced an average annual load increase of 2.88% over the past 10 years. The peak loads in 2014, 2015 and 2016 were 1766MW, 1794MW and 1892MW respectively. To deliver this load there are a total of 14 x 345kV transmission lines totalling 945 miles, 73 x 115kV transmission lines totalling 462 miles and 32 x 69kV transmission lines totalling 204 miles.

The 345KV network is particularly important as it is used to import approximately 645MW, about 30% of the peak load. High availability is essential to maintain power to the service area. The majority of these 345kV lines are in very remote, rough terrain. Two of the lines are in excess of 200 miles long. Consistent, accurate fault location has been an essential operational tool to effectively manage these lines and return significant cost savings by quickly reaching fault sites and minimising downtime.