10kW Wind Turbine 0, Storm 2

Twice in one-and-a-half years.

A mammoth windstorm during Saturday night on February 12th, 2011 has once again "fried" Power One's 6kW inverters, only this time both inverters were affected.  At bedtime, I noticed windspeed was 58 kph as recorded on the residence's Bios weather station.

Last year's mid-May storm affected only one of our two parallel-wired inverters.  This time it's both.

Energy West's Paul Wende on Monday logged onto the controller software via his laptop.
He checked settings and advised that all were within safe operating ranges, but since the controller of the 10 kW wind turbine has no built-in memory, no record exists of the voltage and RPMs of the turbine.
Controller hardware appeared to be physically unaffected by the night's events.

Paul removed the two Aurora inverter covers and announced both inverters "fried".

Paul Wende investigates

A lot of "soot" inside the second inverter

More "soot" inside the first inverter

Inverters were packed into boxes for return to Power One in California, where an investigation will show inverter logs of the last voltages received.  After inverter damage in May of 2010, a new inverter took two months to arrive, its last log indicated maximum voltages had NOT been exceeded!  The two-month timeframe will likely be repeated in this case.

That wasn't the only damage that night.
The new nets and poles at the golf course's west fenceline were still standing, but a hardware bolt--holding the aircraft cable on Pole 3--broke, allowing the cable and net to droop.  Advanced Powerline of Kelowna was called and, five minutes later, their crew drove into the driveway.  A crew member chuckled at my stunned look, "we weren't far away when we got the call from the office!"

Jeff, plus two colleagues on the ground, raised the cable.

"Haven't seen one of those hardware pieces break recently, but they did get some bad ones a couple of years ago."  He added, "Maybe you got one of those."

"Have you got a couple of inverters in your office we could borrow?" suggests Kia.

10 kw Wind Turbine...operational again

Again operational, after two months and four days of downtime! 

Shown (at the right of the two) in the photo, this is the third Aurora inverter installed.

The first--slow to start up even when its parallel partner at the left was sending electricity to the grid last year--failed around midnight on May 19th, 2010. Sent back to Power One in California, after three weeks they had no answer as to why it failed. So the contractor asked for a replacement inverter to be sent. After several weeks it arrived and was programmed and wired parallel, only to discover it had an "internal fault". Power One was again contacted by Paul Wende of Energy West Power, who insisted a new 6 kw Aurora inverter be put onto Air Express to mitigate this lengthy downtime.

The third Aurora 6 kw inverter arrived Thursday, was immediately programmed, then installed Friday.  We're finally up and running again.

Of the changes made, contractor Paul Wende stated "we have implemented an independent braking function so that when the controller senses either a certain RPM, or voltage, or windspeed, or turbine head temperature, that it will apply the 10 kw dumpload in parallel with turbine output, thus loading the turbine and dissipating excess energy." He added: "We basically installed four new wires."

And early the next day, Paul said 16 kilowatts had been produced since Midnight.

"Thank goodness we have another fan going in this heat," pants Kia.