To: dudleydevices@aol.com
Subject: FW: Index Testing Kaplan Turbines using the HIT/ITB
methodology
Apologies for the
delay in writing this. Lee Sheldon’s passing on Christmas Day last year set
things back a bit here. Lee was a mentor and master-swami of hydropower
for the ITB project since 1984. He will be missed, but before he
checked-out we completed a comprehensive optimization at 4-heads of the 5MW
vertical Kaplan at Dorena Dam. He shared how
his “Smooth Curves” analysis technique that he had been using for over 50 years
works. After working with the ITB at Dorena Dam Lee said the ITB’s non-linear
statistical-analysis technique gleans steady-state data so much better that the
Smooth Curves method is no longer needed.
In December you
said it wasn’t the best time for you because your units are running full blast
so I hope this email is timely now to get the ball rolling. Fortunately,
a unit does not need to be shut down to start setting up for our new
optimization technique. In 1988 Ken Pflueger worked with Lee to setup an Index
Test Box demonstration at Wells Dam for BPA who paid for everything. With no
out-of-pocket expense Douglas County would have kept the ($65k-base price) ITB
in exchange for providing a turbine for BPA’s demonstration. It was a good deal
for everyone - but Woodward dropped the ball, the demonstration was
unsuccessful and the ITB project was abandoned. Lee called me in April of 1990 to complain about
Woodward’s failure. After learning that I had returned to working on aircraft
engines Lee urged me to continue working on the ITB personally if Woodward
refused to resume the project. This is what happened, culminating in the
successful 4-head index test at Dorena Dam from 2015 to 2017.
Everyone in the
index testing business has bemoaned that Fracking has reduced the cost of
natural gas fired electricity that at $50k each it’s just not worth index
testing and optimizing Kaplan turbines just to get a few percent more
electricity. The new HIT/ITB method can optimize a Kaplan turbine for
1/10th that cost ($5k per index test) and Lee’s endorsement said the
ITB does a better job of it. It won’t cost you any out-of-pocket funding to
find out for yourself. The deal I’m offering is for no money at all.
If you’ll setup your data recorder for 2-Hz scans and send me a sample of your
normal running data now to get my ITB setup for it and then send me the data
file recorded during a conventional index test, I’ll reduce it to determine the
As-Found and After-Optimization overall efficiency profiles and new 3-D Cam
blade-to-gate profile curve needed to get that indicated improvement. The first
demonstration will be free. If you like it, subsequent index tests and the
resulting as-found, after optimization comparisons will be free – but if you
want the 3-D Cam gate to blade profile curve to get that improvement it will
cost you $5k.
Here are the steps
for an index test:
Background
After Woodward abandoned
the ITB in April 1990 Lee reached out to me personally to say that the ITB was
still needed by BPA, and if the original inventor of record (me) of the ITB
resurrected the project BPA would still be interested as soon as the Patent expired.
The ITB project evolved from 1990 until 2016 under George Mittendorf and Dave
Kornegay’s tutelage until George (1936-2011) and Dave (1947-2016) passed away.
The evolutionary
process improved accuracy and reduced costs by improving the steady-state
algorithm and data processing methods to reduce scatter in the data result and
use only pre-existing powerplant instrumentation and recording equipment.
When Lee was
offered the job, his failing health, the 3-hour round trip drive to the dam and
his Oregon Institute of Technology (OIT) hydropower technology teaching schedule
precluded him performing these 4-index tests using traditional methods. Before
accepting the job Lee recalled our work together with the ITB in 1987 at Portland General Electric Power House
#2 (aka Bull Run Dam) and called to ask, “Can the ITB
perform a remote index test yet?” “Yes,” was the answer, but some
preconditions had to be met. Sufficient instrumentation, a data logger
and a means to position and hold the gates and blades at the required positions
for on and off-cam data points were needed. After a few conversations with the
maintenance personnel at the dam they got everything up to snuff and the test
was ready to go on 2015-11-15 when they sent the first streamed-data file from
their data logger to me.
Lee accepted the
index testing job at Dorena Dam in 2015 where we
employed the new HIT/ITB method commercially to perform a comprehensive
optimization of the 5MW vertical Kaplan turbine there at 4 different heads (48,
69, 85 and 102 Ft). The 4th index test at 102 Ft. gross head
was validated by a traditional, commercial index test by Hatch Inc. An email discussion with Hatch Senior Engineer Peter
Rodrigue clarified a few minor points to confirm the results.
One issue was the non-standard tailwater level sensing method that Peter sorted
and the other was a type-o in Hatch’s final report which was a gimmie.
The project
engineer coined the name, “Hybrid Index Testing (HIT)” to describe how the test
procedure came together. An overall checkout and “tune-up” should be performed
on every new Kaplan turbine immediately upon commissioning to assure the
greatest possible Return On Investment. Lee said that the HIT/ITB combination
worked perfectly and put it in writing in a POWER magazine article 2019-04-01
Optimizing Kaplan Turbine Efficiency with Minimal
Cost, Effort and Time (Sheldon).pdf and in the
FORWARD in a sales pitch to KGS Group.
Index Test Box
About 25 years ago, a device called an Index Test Box
(ITB) was invented. It is capable of performing unattended index tests. In
other words, it’s operated by simply plugging the unit into a governor and
recording performance data while the generating unit remains in normal
operation.
The ITB utilizes a constant power testing method that
does not cause wide swings in flow and power like conventional index testing
methods do. BPA evaluated this device, tested it at Portland General Electric’s
Hydro Plant 2, and found it worked perfectly.
Over the intervening years and culminating in 2016,
the inventor of the ITB perfected a method of achieving the most accurate of
index testing results, without even having to actually conduct any field tests.
This newest technique has been demonstrated at a privately owned, single-unit
Kaplan powerhouse that uses the forebay at Dorena Dam in Oregon, which is owned
by the USACE. This method needs only the data normally recorded on the
station’s supervisory control and data acquisition (SCADA) system.
A software program
from the ITB is used to sort and correlate this data into conventional tabular
format, and then a separate software program, developed by students at the
Oregon Institute of Technology in Wilsonville (OIT), analyzes this data exactly
as if it had been measured by field index tests.
Fig 1. This
excerpt from Lee’s article is critical of USACE’s hydro governors which is
quite likely why he published in POWER Magazine – but I still liked what he
said about my ITB.
At the time of his
passing, Lee was actively engaged at pitching our HIT/ITB methodology to KGS
Group. In his FORWARD to the proposal to KGS he touted our new
way to evaluate hydroelectric turbine health and long-term Condition Monitoring
Lee spoke very highly of the HIT/ITB method.
FORWARD
The following is a description of the latest version of the Index Test Box
(ITB) and its capability as an instrument to advance the state of the art in
monitoring hydroelectric generating units. It is designed to optimize the
performance of individual generating units powered by either Kaplan or Francis
turbines and to monitor their performance and alert an operator whenever there
is a degradation in performance that indicates a need for maintenance. The
original device was developed to be connected to the governor and in an
unattended manner to collect operational data and sort the data for
analysis. It was field tested several times and compared to manually
conducted index tests and found to work perfectly. In fact, it produced
data with virtually no uncertainty or scatter.
The
instrumentation technician invented the software while working at Woodward
Governor Company. Evaluation of signal composition in the frequency domain led
to the development of a nonlinear digital filter to glean steady-state data
from the noisy continuous data streams emanating from the machine.
Unfortunately, the ITB project did not achieve commercial success for Woodward
Governor Company. Some familiarity at index testing is necessary to fully
appreciate the ITB’s accuracy and laborsaving value. There are scant few
engineers with such expertise, especially in management/procurement positions.
Development work
continued on the device, particularly on the aspect of being able to feed
recorded data from the power station SCADA (Supervisory Control and Data
Acquisition System) directly into the ITB as though it was actual field
data. Playback is sped up to over 100 times normal speed. The sorting
process to decide what to keep and what is too noisy is fully automated. This remote
index testing capability was demonstrated to function perfectly in the Dorena
field-tests for index testing a Kaplan turbine. A long-term condition
monitoring system is available to track operational performance of generating
units over time so that maintenance may be scheduled on an as needed basis.
Lee Sheldon,
P.E.
Fig 2. FORWARD to
KGS.
Governor, 3-D Cam
and Blade Controller Checkout
The first step in
any Kaplan index test is to make sure the gates and blades are moving robustly
and positioned accurately. At Dorena the blade setpoint and position were not
available on the SCADA system or data recorder so they had to be brought out of
the blade control system first. It was a good thing too, because they showed a
problem right off the bat. The governor was a “home-brew” made by a
local controls company who had no prior experience with Kaplan governing. It’s
a long story that will come out in the book…
The animation SquirrelyCam.gif shows the
as-found blade-to-gate behavior of the Kaplan turbine at Dorena dam. The first
data logger file was only to checkout the data recorder and how the governor
and blade control systems behave. The time span of the event-record shown is 1
hour and 45 minutes, sped up to 32 seconds to make it easier to visualize
what’s happening. When the blades mounted the cam surface they wandered and
hunted wildly for almost 2 hours before they settled down. Because they didn’t
have blade angle indication anywhere on the system they had no way to see this
problem. To help correct the situation numerous Woodward manuals and industry
standards describing how closed loop systems and Kaplan governors are supposed
to behave were shared with the controls engineer. He took the advice to heart,
revised his governor control system software and the problem was quietly fixed
before the index tests began.
Project Status
Right now I’m
making videos to pitch the software’s function to hydropower agencies.
2015-12-14 Index
Test-1 at 69 ft gross head.wmv - this one is only partially narrated at this
time.
Another general
pitch for index testing took 2 weeks to compose and record.
Index Testing For Fun And Profit.wmv
Here’s how the
HIT/ITB Can Work at Wells Dam.
The biggest
drawback of the original ITB at Woodward was the $65k out of pocket expense to
buy the equipment just to get started. The new HIT/ITB method has a $0
out-of-pocket expense to get started because it uses your existing equipment
and your people do any setup and operational work.
You also don’t
need to shut down a machine to get started. Setup your recorder for 2-Hz scans,
record a bit of normal operational data and send it to me. I’ll use your data
sample to reconfigure the ITB input to read your files and evaluate the data
therein to be ready when you run your next index test. Here’s a 100-row sample of the data from
Dorena Dam as an example of how we did it that time. The only changes they made
to their instrumentation and data recorder was to bring-out the blade setpoint
and blade position to the SCADA system and along with the tailwater level add them
to the SCADA system and data recorder. A 24-hour data set was about 10MB in
size, easily attached to an email for transmission back to me.
Send a sample of
whatever data set and you are recording now for your index testing. I’ll write
a small program to rearrange the column-order to match how the ITB is setup
now. If you bought an ITB program the input format column-order of that copy of
the ITB program would be setup to read your files any way you want them.
To get started,
send me a small sample of your data recorder output as a “.csv” format for
whatever signal set and channel order that you have now.
Setting up for the
Test
The HIT/ITB method
starts by learning how you want to test the unit and inventorying the available
signals.
Efficiency determination
requires this signal list as a minimum:
Additional signals
enable evaluating governor dynamic performance are:
Optional signals
for trending include:
And then a bit of
housekeeping…
The first step is
to inventory the extant instrumentation and compare what is there to the list.
Missing signals are permanently added.
The gates and
blades can be exercised one of three ways:
#1 is the most
commonly used method and is how the example 4-head index test at Dorena Dam was
run and is probably how you run your index tests.
#2 is believed by
some hydropower engineers to have less of an impact on flow in response to
changes in blade angle. It is sometimes used for index tests in run-of-the-river
dams with small forebay ponds. This method is disfavored because in the early
governor designs the blades were more difficult to set than the gates.
#3 is the best way
because it keeps flow and power constant within a few percent while the gates
and blade are swept back and forth along the unit’s Constant Power curves. This
method requires a dynamically-robust and statically-accurate governor. A draft for magazine article expands on the Constant
Power method.
The HIT/ITB
program can use any one of these 3 or any other method you want. The primary
benefit of the ITB is it’s ability to glean the steady-state data from the
noisy continuous data streams emanating from a unit.
Whenever you are
ready, send me a sample of your 2-Hz scans data to get started. We’ll make any
adjustments needed using a trial-and error process.
Best regards,
Douglas Albright
Actuation Test
Equipment Company
(815) 335-1143
