The goal of this project is to design and conduct controlled experiments to systematically optimize manufacturing and testing processes for fluorene isophthalate terephalate (also known as fluorene polyester or FPE) capacitors to encourage the commercial availability of a reliable and affordable supply. Film casting, film metallization, and final capacitor assembly processes will be optimized.
Hamilton Sundstrand, Rockford, IL 61125
Brady Corporation, Milwaukee, WI 53201
Dearborn Electronics, Inc., Longwood, FL 32750
SteinerFilm, Williamstown, MA 01267
Capacitors are an important component of downhole logging-while-drilling (LWD) and measurement-while-drilling (MWD) electronics. There is a need to develop and enhance the electronics industry's capabilities to produce temperature resistant capacitors that will support the use of these tools at greater depths and under more hostile conditions.
FPE technology is currently used to provide high-temperature (HT) capacitors utilized in the aerospace industry. This industry has been using metalized film capacitors for power conditioning, filtering, and energy storage applications for decades. Metalized film capacitors have the ability to “clear” small defects, exhibit high reliability, and tend to fail in a controlled and manageable fashion at the end of a long and useful life. The alternatives have weaknesses: multilayer ceramic (MLC) capacitors have violent failure modes and are highly susceptible to vibration and thermal cycling environments, while electrolytic capacitors have problems with “dry-out”, have short lives, and exhibit low reliability at elevated temperatures. For these reasons, the aerospace industry has focused on metalized film capacitors as the most viable high-temperature capacitor solution.
Unfortunately, FPE capacitors have been manufactured on a “one-of-a-kind-special-order” basis and the industry suffers from poor manufacturing yields at all stages of the manufacturing process. Widespread use of FPE film capacitors (particularly for oil field drilling services applications) will not be practical until they can be efficiently mass-produced in a financially self-sustaining manner. Evidence of manufacturing feasibility will be required before Hamilton Sundstrand and downhole drilling equipment suppliers will be able to design and produce robust, saleable, distributable, and serviceable FPE capacitors.
This research project builds on the strong partnerships currently in place among Ferrania (FPE resin manufacturing), Brady Corporation (film casting), SteinerFilm (film metallization), Dearborn Electronics (capacitor manufacturing), and Hamilton Sundstrand (applications and systems expertise) to develop an optimized production process for HT FPE capacitors. These partners will collaborate on the systematic design of experiments involving four production-sized batches of FPE capacitors.
Successful execution of this effort will result in commercially available, reliable, and affordable 250 °C rated capacitors. HT capacitors could be extensively used in downhole drill motor drives and downhole MWD communication devices provided a reliable and affordable supply is available to the petroleum industry. The increased temperature capability of HT capacitors will minimize the cooling requirements in line-replaceable units (LRUs), allowing other components to utilize valuable heat sink areas. Alternatively, size and weight can be reduced in LRUs by decreasing the heat sink mass. In addition, increased thermal capability will greatly increase the reliability of capacitors. By providing a large thermal de-rating, a capacitor rated at 250 °C will be much more reliable at 150 °C operating conditions. The root-mean-square (RMS) current handling capability of HT capacitors will not be thermally limited when a 250 °C capacitor is used in a 150 °C application in place of conventional low-temperature capacitors.
This project is primarily focused on commercializing cost-effective, reliable, FPE capacitors for downhole applications. This in turn will reduce the drilling costs for developing deep gas resources, improving the likelihood that larger volumes of such resources can fill domestic consumer demand for natural gas at a reasonable price.
The project has been completed. The final report is available below under "Additional Information".