Mel Tyree
2nd July 2010, 13:59
I have failed to get the following message posted on small-wind-home. I think I should give up on them in future:worried: They seem to censor a wide range of comments these days. Maybe that is why the number of comments on that site are down by 75 to 80% from previous monthly activity? Anyway, I don't think I said anything offensive and want others to see what I wrote to Bill Slater. Let me know if you have any viewpoints or comments.
Hi Bill,
Thanks for your interest in BWC inverters. Please keep me informed of how your new BWC turbine with PowerSyncII works out in Edmonton, KY! You seem pleased with it so far. (Bill's original message below) You asked me for more details.
I currently have power, voltage and anemometer sensors etc on 7 turbines (6 in NY & 1 in Alberta).
PowerSyncII sites:
One of the turbines is an old style (ferro-magnet) BWC Xcels with a new PowerSyncII. It works well with few bus voltage outages and none have required manual resets. The owner of this PSII reports electrical noise produced by the inverter that causes AM radio interference in his home and causes his electric clocks to run fast in his home ( 1 h per day gain). I can see this electrical noise on my digital scope as a 15 kHz wave on top of the 60 Hz power output wave. My original GT!0 had a worse problem (higher amplitude 15 kHz noise causing AM radio interference 1/2 mile away and clocks running 10X faster) but this was corrected when the 'mother board' was replaced under warranty.
Soon I will add a new site with a new BWC Excels with Neo magnets, SH3055-23 blades & PowerSyncII, which should be the same as yours. The new systems currently sold by BWC have slightly longer blades.
GridTek10 sites:
Two other sites have the same GridTek10s as mine and I have been monitoring these for 9 months, and these have far fewer bus overvoltage errors (an very rarely require manual resets) even though one site is windier than my site. So I have concluded there is something wrong with my GridTek10. I wanted to learn more about power inverters and MPPT tables for inverters so in my case I installed two 6-kW Aurora inverters because I can program the MPPT tables and study how the MPPT table changes power curves. These Aurora inverters are working fine and give me a 15% improved power curve and since I have fewer outages that require resets I am expecting a 30% boost in annual energy yield. The Auroras have been online since Nov 2009. I have not done a complete analysis of data yet but I think I am on-track for the best-ever year so far in energy production even though wind speeds have been about average. I still have my old GT10 on the wall and this can be switched in or out at will. I am using my GT10 as a backup in case the Auroras should ever fail. I have blown some fuses in the Aurora wind box while trying to optimize the MPPT tables. My Auroras seem unstable when I program tables as generator Hz vs power out but are much more stable (do not blow fuses) when I program DC voltage in vs power out. The instability manifested itself as rapidly changing power out amplitude ( from 1 to 10 kW @ 2 or 3 times per second) even though wind speed was much more stable than that.
Other sites under study:
My other sites are: Two 10 kW Fortis Alize turbines and one 5 kW Endurance and one 3.5 kW Raum (to be installed this summer). I do not have enough data yet on any of these sites to say much. The power curves at the Alize sites are still being optimized for the WindyBoy inverters so it is not useful to anyone if I say much about past performance until the MPPT tables are optimized by Fortis America in Ithaca, NY. In Europe the Alize uses a Fortis-designed 3-phase 50 Hz inverter so they had to switch to a WindyBoy inverter for the small American market.
Recommendation to past and future owners of 10 kW BWC turbines:
BWC has made lots of improvements to their generator and inverters since I bought mine 4 years ago. Mechanically their turbines were always reliable and they are now much-improved electrically. In my opinion BWC turbines are the best option for future buyers of turbines in the 10 kW size-class. I will know more when I have > 12 months of data at all of my sites at which point I will post data and analysis and give talks at small wind conferences. In a rapidly changing small-turbine market, what is 'best' currently may not be best next year.
GridTek10 inverters are also reliable but rather variable in performance. All three inverters I monitor are 'noisy' in different ways. As these old units fail with age, owners will have to repair them or replace them. BWC has always been good at keeping old inverters that are out of production repaired. So far I think the power curve with old Xcels turbines connected to two Auroras is better than an old Xcels (Ferro magnets) connected to a PSII inverter. So a viable option to be considered is to replace old GT10s with new Auroras when costly repairs are needed. Installers can contact Rob Beckers at Solacity Inc for details and I will eventually post technical information on my website too.
Rob@Solacity.com
www.ualberta.ca/~mtyree/SWIEP
Best regards,
Mel Tyree
Mel Tyree, BA PhD (Cantab.) LLD (h.c.) FRSC
Professor
Department of Renewable Resources
444 Earth Sciences Building
University of Alberta
Edmonton, AB, Canada
T6G 2E3
780-492-5597 (Office)
780-902-6771 (Home)
518-594-3815 (Mobile)
From: B or E Slater [mailto:billbob1@scrtc.com]
Sent: Friday, June 25, 2010 8:42 AM
To: Tyree, Mel
Subject: Powersync ll Inverter
Dr. Tyree:
I read with interest your paper; Detailed Response to Mike Bergey 1/22/2009. At the end of the paper you asked Mike to "sell" you a Powersync ll so that you could provide analysis.
I recently installed a BWC Exel 10 Kw turbine with the Powersync ll. We have had the system for about a month now. At first we were experiencing over volt line faults during higher wind speeds. I don't have accurate data on the wind speed but suffice to say that it was probably not in excess of 35 mph and probably more in the mid 20 mph range. The over volt problem was apparently rectified by adjusting the threshold to 264. Now we are getting an under volt fault and curiously one of the under volt faults has occurred with little to no wind speed.
Did you ever get the opportunity to evaluate the Powersync ll? If so, I;d appreciate your insights. When you have the time. If you care to call, I have an "800" number: 1-800-282-2206.
Thanks
Bill Slater
Edmonton KY
Hi Bill,
Thanks for your interest in BWC inverters. Please keep me informed of how your new BWC turbine with PowerSyncII works out in Edmonton, KY! You seem pleased with it so far. (Bill's original message below) You asked me for more details.
I currently have power, voltage and anemometer sensors etc on 7 turbines (6 in NY & 1 in Alberta).
PowerSyncII sites:
One of the turbines is an old style (ferro-magnet) BWC Xcels with a new PowerSyncII. It works well with few bus voltage outages and none have required manual resets. The owner of this PSII reports electrical noise produced by the inverter that causes AM radio interference in his home and causes his electric clocks to run fast in his home ( 1 h per day gain). I can see this electrical noise on my digital scope as a 15 kHz wave on top of the 60 Hz power output wave. My original GT!0 had a worse problem (higher amplitude 15 kHz noise causing AM radio interference 1/2 mile away and clocks running 10X faster) but this was corrected when the 'mother board' was replaced under warranty.
Soon I will add a new site with a new BWC Excels with Neo magnets, SH3055-23 blades & PowerSyncII, which should be the same as yours. The new systems currently sold by BWC have slightly longer blades.
GridTek10 sites:
Two other sites have the same GridTek10s as mine and I have been monitoring these for 9 months, and these have far fewer bus overvoltage errors (an very rarely require manual resets) even though one site is windier than my site. So I have concluded there is something wrong with my GridTek10. I wanted to learn more about power inverters and MPPT tables for inverters so in my case I installed two 6-kW Aurora inverters because I can program the MPPT tables and study how the MPPT table changes power curves. These Aurora inverters are working fine and give me a 15% improved power curve and since I have fewer outages that require resets I am expecting a 30% boost in annual energy yield. The Auroras have been online since Nov 2009. I have not done a complete analysis of data yet but I think I am on-track for the best-ever year so far in energy production even though wind speeds have been about average. I still have my old GT10 on the wall and this can be switched in or out at will. I am using my GT10 as a backup in case the Auroras should ever fail. I have blown some fuses in the Aurora wind box while trying to optimize the MPPT tables. My Auroras seem unstable when I program tables as generator Hz vs power out but are much more stable (do not blow fuses) when I program DC voltage in vs power out. The instability manifested itself as rapidly changing power out amplitude ( from 1 to 10 kW @ 2 or 3 times per second) even though wind speed was much more stable than that.
Other sites under study:
My other sites are: Two 10 kW Fortis Alize turbines and one 5 kW Endurance and one 3.5 kW Raum (to be installed this summer). I do not have enough data yet on any of these sites to say much. The power curves at the Alize sites are still being optimized for the WindyBoy inverters so it is not useful to anyone if I say much about past performance until the MPPT tables are optimized by Fortis America in Ithaca, NY. In Europe the Alize uses a Fortis-designed 3-phase 50 Hz inverter so they had to switch to a WindyBoy inverter for the small American market.
Recommendation to past and future owners of 10 kW BWC turbines:
BWC has made lots of improvements to their generator and inverters since I bought mine 4 years ago. Mechanically their turbines were always reliable and they are now much-improved electrically. In my opinion BWC turbines are the best option for future buyers of turbines in the 10 kW size-class. I will know more when I have > 12 months of data at all of my sites at which point I will post data and analysis and give talks at small wind conferences. In a rapidly changing small-turbine market, what is 'best' currently may not be best next year.
GridTek10 inverters are also reliable but rather variable in performance. All three inverters I monitor are 'noisy' in different ways. As these old units fail with age, owners will have to repair them or replace them. BWC has always been good at keeping old inverters that are out of production repaired. So far I think the power curve with old Xcels turbines connected to two Auroras is better than an old Xcels (Ferro magnets) connected to a PSII inverter. So a viable option to be considered is to replace old GT10s with new Auroras when costly repairs are needed. Installers can contact Rob Beckers at Solacity Inc for details and I will eventually post technical information on my website too.
Rob@Solacity.com
www.ualberta.ca/~mtyree/SWIEP
Best regards,
Mel Tyree
Mel Tyree, BA PhD (Cantab.) LLD (h.c.) FRSC
Professor
Department of Renewable Resources
444 Earth Sciences Building
University of Alberta
Edmonton, AB, Canada
T6G 2E3
780-492-5597 (Office)
780-902-6771 (Home)
518-594-3815 (Mobile)
From: B or E Slater [mailto:billbob1@scrtc.com]
Sent: Friday, June 25, 2010 8:42 AM
To: Tyree, Mel
Subject: Powersync ll Inverter
Dr. Tyree:
I read with interest your paper; Detailed Response to Mike Bergey 1/22/2009. At the end of the paper you asked Mike to "sell" you a Powersync ll so that you could provide analysis.
I recently installed a BWC Exel 10 Kw turbine with the Powersync ll. We have had the system for about a month now. At first we were experiencing over volt line faults during higher wind speeds. I don't have accurate data on the wind speed but suffice to say that it was probably not in excess of 35 mph and probably more in the mid 20 mph range. The over volt problem was apparently rectified by adjusting the threshold to 264. Now we are getting an under volt fault and curiously one of the under volt faults has occurred with little to no wind speed.
Did you ever get the opportunity to evaluate the Powersync ll? If so, I;d appreciate your insights. When you have the time. If you care to call, I have an "800" number: 1-800-282-2206.
Thanks
Bill Slater
Edmonton KY