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By Julian Nettlefold

07 Oct 08. “The added power requirements caused by the addition of complex C4I, IED-defeat and EO systems on today’s battlefields have reached critical levels,” Gary Smith, VP & General Manager of DRS Test & Energy Management Inc. told BATTLESPACE at this year’s AUSA. “We know of one particular vehicle type which actually experiences brown-outs during combat when all its systems are in use.”

There are a number of key programs being initiated in the USA to meet this challenge for legacy and new vehicle fleets. Both the Joint Light Tactical Vehicle (JLTV), in the USA, and the Operational Utility Vehicle System (OUVS), in the U.K., have mandated an on-board generating requirement of 30kW of 120/208V (in the USA), 3-phase utility-grade power.

Toward this end the Navy’s Office of Naval Research awarded the On-Board Vehicle Power Program (OBVP) to DRS Test & Energy Management Inc. DRS offered a combination of a 30Kw generator embedded within the bell housing of the Marine Corps M1123 HMMWV’s existing transmission thus saving space and minimizing the impact of this generating capability to the existing vehicle design. Prototype hardware has already been built and extensively tested in DRS’s System Integration Laboratory (SIL). The equipment has now been installed in the required M1123 HMMWV where it will continue to be tested as a fully integrated system. The specification requires the system to generate a total of 30 kWatts of exportable electric power while the vehicle is stationary and 11Kw while the vehicle is moving (power is restricted due to engine capability and mobility requirements). The ONR requirement also stipulates that the unit must provide either AC and DC power for specific missions. One of the key applications of the system, also recognized by the U.K. MoD, was the system’s ability to provide battery charging for tactical radio batteries and soldiers.

DRS displayed its transmission embedded solution at this year’s AUSA which generated great interest. The solution provided by DRS offers:

* Flexibility. The system can be forward-fit into new products such as MRAP, JLTV and OUVS or retrofit into existing HMMWV and Land Rover-type products.

* Reliability. The DRS solution provides the embedded generator design with no extension in overall driveline length. This is a very important feature when retrofitting existing vehicles. Mounted totally within the stock transmission envelope, it is possible to integrate the 30 kWatt generation capability by simply removing the existing transmission and replacing it with a modified unit. Power management and conversion electronic LRU’s can then be mounted in convenient locations around the vehicle. Installation of the equipment does not impede the operation of the vehicle’s power train when power is not being generated nor does it require extensive modification of any other vehicle components. Special control algorithms insure that the engine is operated at sufficient speed to support the amount of power requested. An on-board CANbus provides digital communications and controls between the generator and power management systems and allows this information to be integrated with electrical loads and load controlling devices.

* Versatility. The DRS generator is designed to operate in all military conditions, including desert conditions, water fording, salt/fog, sand, temperature extremes, abrasion, shock, vibration and contamination. It can also be scaled up or down in total power capability based on engine and transmission size and capacity.

Mr. Smith indicated that independent developmental testing will begin early next year by ONR to evaluate the operation and battlefield suitability of this power generation concept before moving on to production. In the mean time, efforts are underway to transition this technology to a number

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