SBIR-STTR Award

Many military missions involve the use of equipment that requires small batteries for power where AC grid power is unavailable. Also, there is a need for a high quality power output device that conditions a power input to make it suitable to power sensitive communications equipment. The weight of this equipment is also a factor which affects Its usefullness in quick moving military situations. Maintaining uninterrupted power at these locations can be critical in some situations. In the event of a power generation failure, there needs to be a carry-through period where the batteries in the power conditioning equipment can satisfy load requirements. The generators that supply power are often off-line unexpectedly and/or for random periods of time. Failure of this equipment can affect the ability of a military group to carry out its mission. An Uninterrupted Power Supply (UPS) is needed that supplies backup, has flexible input and output options, does not add significant weight or logistical burden to a mission and is rugged and able to withstand extremes of physical and environmental conditions. The currently available commercial off-the-shelf (COTS) UPS's are not suitable solutions for the above-described problem. These COTS units do not have variable input and output options, are not rugged and use valve regulated lead acid batteries that are heavy and make the unit inflexible for other applications. The research contemplated by this proposal would lead to the development of a Marine Portable Power Unit (MPPU) that can serve as both an UPS and a battery charging station. The unit should be designed around currently deployed military batteries so as to enhance its flexibility of use. The MPPU ideally would be under 50 pounds in weight. It should have multiple input and output power configurations, specifically 12 VDC, 24 VDC, and 120 VAC single phase 60 Hz capability. The unit should use the BB-2590/U Lithium Ion battery and be able to safely handle batteries in multiple series/parallel configurations. The system should be able to act as both an UPS and a battery recharging station with batteries easily able to hot swap in-and-out.

Keywords:
Uninterruptible Power Supply, Lithium Ion Batteries, Man Portable, Battery Charger, Current Conditioning, Rugged, Dual Voltage Input/Output

A conceptual design of a battery charging station with UPS back-up capability was completed under contract M67854-C-6509. The resulting system can charge up to twelve BB-2590 batteries at the maximum charging current (to minimize charging time) and provide 1000 Watts of back-up power (both AC and DC outputs are provided) for at least one hour. Individual batteries can be hot-swapped for field use in other equipment without interrupting the on-line UPS capability. The system accepts both universal AC and external DC power inputs, allowing use with worldwide power grids, portable generators, and automotive alternators. The system will implement Acumentrics’ field-proven environmentally ruggedized mechanical design and thermal management technology to ensure performance in potentially harsh environments. The objective of this proposal is to complete a detailed design of the conceptual system defined during the Phase I effort. All subsystems will be tested both individually and in a brassboard system configuration prior to completion of the system detailed design. Four prototype systems will be built and tested to ensure all power and functional requirements have been met. Two systems will then be delivered to the sponsor for end-user evaluation and two will be subjected to shock, vibration, environmental and EMI/EMC tests.

Keywords:
Ups, Rugged, Battery Charger, Universal Ac Input, External Auxiliary Dc Input, Lithium Ion Battery, Bb-2590