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Pratt, Richard M

Publications and source records attributed to Pratt, Richard M.

Grid regulation services for energy storage devices based on grid frequency

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

25 ENERGY STORAGE↗

Grid regulation services for energy storage devices based on grid frequency

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

25 ENERGY STORAGE↗

Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems

Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems. According to one aspect, a battery charging control method includes accessing information regarding a presence of at least one of a surplus and a deficiency of electrical energy upon an electrical power distribution system at a plurality of different moments in time, and using the information, controlling an adjustment of an amount of the electrical energy provided from the electrical power distribution system to a rechargeable battery to charge the rechargeable battery.

25 ENERGY STORAGE↗

Vehicle to Grid Communication Standards Development, Testing and Validation - Status Report

In the US, more than 10,000 electric vehicles (EV) have been delivered to consumers during the first three quarters of 2011. A large majority of these vehicles are battery electric, often requiring 220 volt charging. Though the vehicle manufacturers and charging station manufacturers have provided consumers options for charging preferences, there are no existing communications between consumers and the utilities to manage the charging demand. There is also wide variation between manufacturers in their approach to support vehicle charging. There are in-vehicle networks, charging station networks, utility networks each using either cellular, Wi-Fi, ZigBee or other proprietary communication technology with no standards currently available for interoperability. The current situation of ad-hoc solutions is a major barrier to the wide adoption of electric vehicles. SAE, the International Standards Organization/International Electrotechnical Commission (ISO/IEC), ANSI, National Institute of Standards and Technology (NIST) and several industrial organizations are working towards the development of interoperability standards. PNNL has participated in the development and testing of these standards in an effort to accelerate the adoption and development of communication modules.

33 ADVANCED PROPULSION SYSTEMS↗

Systems and methods for free space optical communication

Free space optical communication methods and systems, according to various aspects are described. The methods and systems are characterized by transmission of data through free space with a digitized optical signal acquired using wavelength modulation, and by discrimination between bit states in the digitized optical signal using a spectroscopic absorption feature of a chemical substance.

47 OTHER INSTRUMENTATION↗

RFID tag modification for full depth backscatter modulation

A modulated backscatter radio frequency identification device includes a diode detector configured to selectively modulate a reply signal onto an incoming continuous wave; communications circuitry configured to provide a modulation control signal to the diode detector, the diode detector being configured to modulate the reply signal in response to be modulation control signal; and circuitry configured to increase impedance change at the diode detector which would otherwise not occur because the diode detector rectifies the incoming continuous wave while modulating the reply signal, whereby reducing the rectified signal increases modulation depth by removing the reverse bias effects on impedance changes. Methods of improving depth of modulation in a modulated backscatter radio frequency identification device are also provided.

Scott, Jeffrey Wayne↗