Test results and initial operating experience for the BPA 500 kV thyristor controlled series capacitor design, operation, and fault test results

A cooperative effort has resulted in the construction of the first 500 kV Thyristor Controlled Series Capacitor (TCSC). This device is installed on the Bonneville Power Administration (BPA) transmission system in the Northwestern United States. Project participants included BPA, the Electrical Power Research Institute (EPRI), General Electric Company (GE), and the Portland General Electric Company (PGE). The TCSC was commissioned in the fall of 1993, initiating an extended test and evaluation period. Evaluation tests included: harmonic performance, staged system faults, subsynchronous resonance (SSR) torsional mode damping, and system swing damping performance. Results of the system tests illustrate the TCSC's ability to improve power system operation. Upon completion of the evaluation tests, the TCSC was placed into commercial operation in January 1995. This initiated a one year trial operational period to evaluate the long term operation of the device.