Trace UL and stupidity [RE-wrenches] + Islanding Patent

Wed Nov 28 15:48:35 PST 2001

Bill - I would like to set the record straight on this.

FIRST! - we have no plans of making our patent a way to prevent other
companies from connecting with the grid.  We are still developing a business
strategy for this, but at the most, would charge a nominal royalty that
would support further islanding research at AE, and more importantly,
islanding evangelism with the utilities (i.e., it really works), and support
for other inverter companies to use this technology.  There are many fine
points to making it work well.
We see the RLC test as being ultimately unwieldy and very time consuming and
would like to move standards to the "Sandia" method with verification that
it is working properly - this would also protect against multiple inverters
using different schemes possibly islanding, which is not currently tested
for.

SECOND! - a little history - Advanced Energy has been working on the
islanding problem since the mid 1990's.  We privately funded Mike Ropp to do
some of the first academic research in this area while he was a grad student
at Georgia Tech.  Mike found that the technique that we had been using up to
that point (basically generating a reference current waveform that was a
little slow, or fast) had "non-detect" zones when tested with the RLC
circuit.

After a lot of thinking and experiment here at Advanced Energy, we came up
with the accelerated feedback methods.  Then, on about November 10th, 1997,
Russ Bonn of Sandia contacted us and said that he wanted to have an industry
meeting on islanding - that it was such an important issue that we had to
meet with two weeks notice, and get together a few days before thanksgiving.

I realized that going to the meeting without filing a patent on what we had
invented would mean that I could not talk about it, so I wrote a provisional
patent application and filed it on November 24, 1997.

AT THE MEETING, Greg Kern of then Ascension Technology (now part of Schott
Applied Power) presented the results of his Federally Funded research -
basically that the techniques that he had been trying could not pass the RLC
test, and that this was potentially a big problem for the industry as
parallel efforts in the IEEE 929 working group relied on the concept of a
"non islanding inverter" to allow us to interconnect on a wide scale.
Ascension had, up until this time, proposed a proprietary scheme of theirs
(code named Zebra).

Later in the meeting, I presented Advanced Energy's anti-islanding
technique, and clearly stated that our work had been filed for a provisional
patent.  A copy of the provisional application was also sent, soon after, to
the IEEE 929 working group (so Bill - if you can check your 1997 email
archive, it should still be there..).

AS TIME WENT ON, Greg Kern and Sandia implemented our method in test
inverters, and found it to work very well.  They published reports on this
and called it the "Sandia Method".  Advanced Energy sent Sandia staff an
email reminding them that the method was subject to a provisional patent,
but never received a response.  I thought that this was not an issue worth
pursuing unless the final patent was granted.  But now it has been granted,
and we do want to set the record straight.

If we had not released our intellectual property at that meeting, we may not
have had an industry solution to islanding, and could have met a road block
in trying to develop IEEE 929, our national standard.

The work that Sandia has done is very valuable, and they have to be thanked
for that.  However, the business model that is used in our country is that
companies use intellectual property to make profits that pay for employees
pay checks.  We have spent hundreds of thousands of our own funds on
islanding research and testing.  It takes a lot of time and money to develop
inverter designs that can grid connect reliably and safely (the Multimode
family cost more than $2 million to develop..).

We plan to use our patent to further the PV industry and to make
grid-interconnection easier and safer.  What more could you want?

Regards

Rob Wills
Advanced Energy

-----Original Message-----
From: Bill Brooks [mailto:billbrooks7 at earthlink.net]
Sent: Monday, November 26, 2001 1:46 PM
To: RE-wrenches at topica.com
Cc: Chuck Whitaker
Subject: RE: Trace UL and stupidity [RE-wrenches]

Drake, Larry, and Rob,

The anti-islanding scheme was conceived and developed by Sandia National
Labs with federal funding. Advanced Energy apparently filed for a patent on
this process or some variation of it. If the process is identical to the one
developed by Sandia, than it is based on previous science and therefore the
patent office made a mistake awarding the patent to Advanced Energy.

Any manufacturer is free to apply the Sandia anti-islanding method. If
Advanced Energy decides to use there patent to prevent companies from
applying that federally funded method, that would be a very unwise (and
unpopular) move and would not hold up in a court of law with appropriate
expert witness.

Bill.

-----Original Message-----
From: Drake Chamberlin - Electrical Energy
[mailto:solar at eagle-access.net]
Sent: Monday, November 26, 2001 9:32 AM
To: RE-wrenches at topica.com
Subject: Re: Trace UL and stupidity [RE-wrenches]

Hi Larry and Rob,

Thanks for your comments.

It is good to hear that Advanced Energy has a solution to the problem of
islanding.  If it becomes available now, it may prevent yet another
debilitating institutional barrier, hobbling the progress of small scale,
privately owned photovoltaic systems connected to the grid.  I hope it is
economical and easy to implement.

I agree with Larry that the utility disconnect is not used.  The
requirement to install it has only been another hoop to jump through, as
far as I can tell.  But, in the event that an inverter failed to shut down,
a utility disconnect could be useful.

Rob said:
"Line-person safety is, as Larry Elliot, pretty much a red herring as the
NESC (the utility's NEC) etc. require a practice of testing and grounding
before working."

We all are apparently in strong agreement on this point.

During the days when "the powers that be" sought an energy economy based on
the Liquid Metal Fast Breeder Reactor (LMFBR), it was acknowledged that
tens of thousands of children would die of leukemia due to the
technology.  It was argued that this was acceptable since coal and other
technologies had similar degrees of health impact.

But, if solar electrical generation could "possibly" harm even one person,
drastic measures must be taken!  I am just curious to learn if there has
been one single problem to date.

If automobiles were held to the same safety standards as grid interactive
inverters, driving would have been outlawed years ago.  In any city, one
can hear sirens scream around the clock.

Maybe the islanding potential of Trace inverters really is a serious
hazard.  I'd just like to see some examples of the havoc that has been
created.  Maybe transformers are exploding like strings of lady fingers on
the Forth of July.  Maybe crispy linemen are dropping off power poles like
insects from bug zappers on a summer night in Louisiana.  ( - :

If so, lets see the statistics.

Peace,

Drake

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

==^================================================================
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9
Or send an email to: RE-wrenches-unsubscribe at topica.com

T O P I C A -- Register now to manage your mail!
http://www.topica.com/partner/tag02/register
==^================================================================