Communications: electrical – Systems – With specific power supply
Reexamination Certificate
2003-04-09
2004-11-16
Crosland, Donnie L. (Department: 2636)
Communications: electrical
Systems
With specific power supply
C340S693400, C340S007320, C455S574000, C455S127100, C455S127500, C363S019000, C320S153000, C307S064000, C307S066000, C136S208000, C330S297000, C330S130000, C330S199000
Reexamination Certificate
active
06819226
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to the field of data telemetry; and specifically to a system of method for storing energy for later use in electronic devices used in land-based telemetry.
2. Description of Related Art
Electronic metering and telemetry devices must accurately measure the flow or use of services, products or materials to external customers or internal processes. In addition to accurately measuring (“metering”) such quantities, the telemetry device must be able to transmit the measured quantity and other information to another device with a low margin of error in such transmission or receive information transmitted by another device. Often such transmission or receipt must occur when the telemetry device has lost its primary power source. Therefore, most electronic telemetry devices have a back-up power source and are designed with several common characteristics in mind, including: operating reliably and accurately over a wide temperature range; continuing to function for a limited time after the failure of the primary power source; operating continuously, reliably and without maintenance in excess of ten years; and being physically small enough for the desired application. Additionally, the telemetry device may consume peak power exceeding the instantaneous capability of the primary power source when the primary source is available or “on” and any back-up power source must be designed to supply this additional energy.
Although implementing each of these requirements separately poses some difficulty, it is extremely difficult to address all five simultaneously. The practical energy storage devices for these applications are batteries, electrolytic capacitors, and a class of capacitors commonly referred to as “Super” capacitors or “SuperCaps.” Generally, SuperCaps are capacitors with very high storage capacitance (e.g., on the order of one Farad, or higher). A drawback to SuperCaps is their very high “equivalent series resistance” or “ESR.” Recently, SuperCaps have been developed with intrinsically low ESR (e.g., on the order of less than one-half ohm DC resistance). These SuperCaps with low ESR are commonly referred to as “UltraCaps.” UltraCaps are commercially available from companies such as Cooper Electronic Technologies, a division of Cooper Industries, Ltd. (a Bermuda corporation, headquartered in Houston, Tex.) and Maxwell Technologies of San Diego, Calif.
Batteries are generally not a practicable solution to meet the above criteria because of their need for maintenance, their reduced life and because their operational characteristics are affected by temperature variations. SuperCaps (and to a lesser degree, UltraCaps), fail to operate consistently over wide variations in temperature. Furthermore, electrolytic capacitors are often large and bulky and rapidly discharge after a primary source power outage because of large leakage currents at high temperatures.
Because the life of batteries that are appropriate for these applications falls short of ten years and standard electrolytic capacitors are physically too large, it is more probable that the temperature performance of UltraCaps may be enhanced in some manner. Enhancing the performance of UltraCaps over a range of temperatures requires understanding the mechanisms that affect UltraCaps at temperature extremes: at low temperatures, the internal ESR of the capacitor increases notably, thereby decreasing the available energy at higher currents; and standard charging voltages at elevated operating temperatures may damage the internal materials of an UltraCap.
One way to address these issues is to operate the UltraCaps at a lower voltage at higher temperatures and to apply heat to the UltraCaps at low temperatures. This solution is problematic in that heating the UltraCaps requires additional energy that may not be available and operating the UltraCaps at a lower voltage requires an increase in the size or number of UltraCaps, in conflict with the need to keep the energy source small. Therefore, what is needed is an electronic metering and telemetry device and associated back-up power supply that simultaneously operates reliably and accurately over a wide temperature range; continues to function for a limited time after the failure of the primary power source; operates continuously, reliably and without maintenance in excess of ten years; is physically small enough for the desired application; and with a back-up power source capable of supplying additional energy when the telemetry device consumes peak power exceeding the instantaneous capability of the primary power source when the primary source is available or “on.” This invention demonstrates a method and system of meeting all of the design criteria using UltraCaps, while considering all of the device's shortcomings.
BRIEF SUMMARY OF THE INVENTION
The invention is a system and method for using a class of capacitors known as “UltraCaps” to provide energy storage in electronic devices. In particular, the invention provides energy storage for land-based telemetry devices. Specifically, the invention measures ambient air temperature and changes the voltage applied to one or more UltraCaps connected in series based on the measured ambient temperature.
The invention involves two power supplies, an input power supply and an output power supply, and one or more UltraCaps. The input power supply receives power from a primary power source, supplies charging voltage to the UltraCaps, and supplies power to the output power supply. The output power supply receives power from the input power supply and/or the UltraCaps and provides a constant voltage output for use by the telemetry device for its operation.
One or more of a microprocessor, microcomputer, microcontroller, control circuit or other external means controls the power supplies. The external control system may be associated with an associated metering device or the telemetry device. One or more algorithms controls the input power supply such that a lower voltage is applied to the UltraCaps at higher temperatures to prevent damaging the UltraCaps and a higher voltage is applied at low temperatures to compensate for internal energy dissipation caused by higher ESR. At lower temperatures the higher voltages do not damage the UltraCaps and in no case does the applied voltage exceed the manufacturer's ratings for the UltraCap.
In the event of a failure to the primary power source, the input power supply shuts down and power is furnished to the output power supply by one or more UltraCaps. The output power supply, in turn, provides power to the telemetry devices for a limited amount of time to enable the device to continue to receive and transmit information.
REFERENCES:
patent: 5251179 (1993-10-01), Wittman
patent: 5446453 (1995-08-01), Nagamoto et al.
patent: 5745532 (1998-04-01), Campana, Jr.
patent: 5748104 (1998-05-01), Argyroudis et al.
patent: 5757172 (1998-05-01), Hunsdorf et al.
patent: 5883886 (1999-03-01), Eaton et al.
patent: 5969436 (1999-10-01), Chalasani et al.
patent: 6208266 (2001-03-01), Lyons et al.
patent: 6246677 (2001-06-01), Nap et al.
patent: 6272190 (2001-08-01), Campana, Jr.
patent: 6388628 (2002-05-01), Dettloff et al.
patent: 6437692 (2002-08-01), Petite et al.
patent: 6459175 (2002-10-01), Potega
patent: 6480699 (2002-11-01), Lovoi
patent: 6538577 (2003-03-01), Ehrke et al.
patent: 2002/0014880 (2002-02-01), McAndrews
patent: 2002/0072868 (2002-06-01), Bartone et al.
patent: 2002/0082748 (2002-06-01), Enga et al.
patent: 2002/0084940 (2002-07-01), Dettloff et al.
patent: 2002/0109607 (2002-08-01), Cumeralto et al.
patent: 2002/0145537 (2002-10-01), Mueller et al.
patent: 2002/0161536 (2002-10-01), Suh et al.
patent: 2002/0193144 (2002-12-01), Belski et al.
patent: 2003/0034900 (2003-02-01), Han
patent: 2003/0036810 (2003-02-01), Petite
patent: 2003/0036822 (2003-02-01), Davis et al.
patent: 2003/0048199 (2003-03-01), Zigdon et al.
patent: 2003/0063723 (2003-04-01), Booth et al.
patent: 2003/0085621 (2003-05-01), Potega
Alston & Bird LLP
Crosland Donnie L.
SmartSynch, Incorporated
LandOfFree
Systems and methods for energy storage in land-based... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Systems and methods for energy storage in land-based..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Systems and methods for energy storage in land-based... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3282901