Aerial picture of a hydroelectric in Canada. Photo: ViaLite/Shutterstock.

Hydro-Quebec, which operates more than 60 hydroelectric power plants in Canada, including the ninth largest in the world with a total installed capacity of over 36,000 MW, has installed Radio Frequency (RF) over fiber links from ViaLite.

With hydroelectric plants, accurate regulation of the speed of power generator units is crucial as all the other systems depend on this performance. The systems regulating this can be highly automated but must be precisely timed.

To accomplish this, Hydro-Quebec uses a new Symmetricom XLi Time and Frequency System, which synchronizes the frequency from the transport line and gives it a precise time stamp. The timing signal feed comes from a remote GPS antenna and is transported using RF over fiber. Hydro-Quebec selected ViaLite fiber links instead of coaxial cables to prevent distortion and loss.

Originally Hydro-Quebec stated it tried syncing the Symmetricom unit with an Inter-Range Instrumentation Group B (IRIG-B) signal, but as this was not accurate enough the company decided to use GPS as the primary input and IRIG-B signal as the secondary.