Document ymRXndEyd0obgw96xYwBbpD16

This simplified map oj the Bonneville system shows the. location of theJour Elliott 50,000-kia synchronous condensers. The Olympia substation is located at the base of the Olympia peninsula, the J. P. Alvey substation in Midwestern Oregon, the Midway substation lies at the hub of the system in central Washington} and the Anaconda substation is in Montana. Elliott synchronous condensers on the Bonneville power system by W. P. VonVranlteii, Application Engineer, Ridgway Division, Elliott Company Four Elliott synchronous condensers serve as Alvey, Midway, and Anaconda--a 3-phase, 60- "balance wheels" on the extensive power network cycle, 13,800-volt condenser is connected to the of the Bonneville Power Administration in north 230-kv bus through a suitable transformer. Each western United States. Under normal or "static" condenser is intended to help stabilize voltage conditions, the condensers merely act like static under either steady-state or transient conditions. capacitors, delivering about half their capacity to For example, the lagging rea:tive capacity of the the system in leading kilovars. In the event of un Anaconda unit generally serves to limit voltage rises usual load fluctuations or of a fault on the system, which are induced by light loads and the effects of however, the condensers automatically pitch in to line-charging current. The J. P. Alvey condenser, help maintain system stability. on the other hand, is called upon to deliver leading Each of the Bonneville condensers is a hydrogen- reactive kva, thus preventing voltage drop in this cooled unit, rated 50,000 kva at 0.5 psi or 60,000 more heavily loaded area of the system. kva at 15 psi. They are among the largest of this All of the condensers perform perhaps their most type in operation today. Engineering studies of important function in the event of faults. System present and potential system requirements indi faults are usually accompanied by a severe drop in cated that for best system stability the condensers line or bus voltage. High-speed (3-cycle) reclosing should be located at four widely separated points circuit breakers are installed which disconnect on the system, as shown on the accompanying a faulted line and lock it open if the fault has simplified sketch of the system. not cleared after a certain number of automatic i*- At each of four substations--Olympia, J. P. reclosings of the breaker. 29