Analysis and Control of Transient Overvoltages on UHV Transmission Systems

The results of a comprehensive study of transient overvoltages on a UHV transmission network are presented. In the study, the expected magnitudes of switching overvoltages due to the energization and reclosing, operations were evaluated for a conceptual 1500-kV system. Fault initiation and fault clearing overvoltages were also studied. The sensitivity of transient overvoltages to network configuration and to key system parameters was examined. The effectiveness of various means of overvoltage control was evaluated. It is demonstrated that the overvoltages can be reduced to a practical level depending on the type and complexity of the control technique utilized.