Victoria Weekend

It was a cold, wet, windy weekend, and everybody came to open their cottages anyways. Lion’s Head was hopping. There were lineups in the grocery store, the liquor store, the convenience store. The crane was there to put the boats in. And electricity demand was HIGH.

Of course, they were Lion’s Head versions of lineups. I had to wait for a car before turning left. Unbelievably stressful. I don’t know how folks manage in Toronto or Kitchener.

But electricity demand was through the roof. I know, because the turbine shut down due to low voltage, and assymetric voltage – basically brownouts. It was like clockwork. At 8 AM, as people rose, and started coffee, toasters, and turned up the heat, the problem surfaced. And even though I had a low voltage ride through package installed on the turbine, that lets it operate through to 90% of nominal voltage, instead of 95%, the voltage dropped by more than 10%.

So I called Hydro One. They have a tap changer on the transformer in Owen Sound that feeds the Peninsula. It adjusts automatically, but they manually over rode it to try to increase voltage further. It wasn’t enough. Demand on Saturday was 300 amps. On Thursday, before the cottagers arrived, and when it was a bit warmer, demand peaked at about 120 amps. The turbine produces a maximum of 26 amps in the high winds we had, so the production was not enough to withstand the demand related brownout on the line. Hydro One was helpful, but evidently the problem is not easily resolved with existing equipment. Perhaps the addition of two more turbines would help.

By Saturday night around 11 PM, voltage was back up, and so was the turbine. Same thing on Sunday. And Monday, the voltage was back by around 3PM, as people left for the south, so the turbine reconnected.

One of the problems with the situation is that the voltage on the line in Owen Sound appears OK to Hydro One. But by the time it gets here, it has dropped considerably. The turbine was measuring voltages in the generator as low as 351 V on a phase, whereas it is normally 390-400. And the voltage on the different phases was substantially different. It is likely that more cottages are served from one phase than the other two, and so that phase drops by more. The turbine controller detects these problems, and shuts down to protect itself. When voltage drops, the current increases, creating excess heat.
Consumers don’t feel this brownout, as they are served by feeders that are north of the Ferndale regulating station. But the turbine is south of there.

Perhaps the addition of 2 turbines will help, as then maximum production will be a greater percentage of the load.

In addition to lost production, it is embarassing to have the turbine off when so many people are visiting. This problem is far less common on other summer long weekends, probably because they are warmer, so demand does not spike as much.

The normal high for this time of year is 17 degrees C.  It didn’t get above 7 degrees on Monday.

I will call Hydro One tomorrow to see if there is anything else that can be done.

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