Lifting of Transmission Towers Under Liver Line Conditions

To maintain adequate conductor ground clearance under emergency operating conditions, tower raising was required on existing double-circuit 230 kV transmission lines. A special tower lifting system was developed for raising towers while adding tower extensions all without de-energizing the lines. Since the method and equipment was unique, a major performance/acceptance test program was conducted which also served to confirm design assumptions. The system was demonstrated on a three-tower test line.