Magnetic current sensors for Space Station Freedom

The magnetic current sensor presented was created under the guidance of the NASA Lewis Research Center and is dependable, lightweight, and stable over time and temperature. Flexible topology allows the design of a pin programmable hybrid package which contains analog and digital circuitry necessary for both bidirectional and unidirectional current sensing. Current ranges at different control points of the system are from 0 A to 10 A up to 0 A to 300 A. The lower ranges have a high peak value; for example, the 10 A current sensor may see 300 A during a fault condition. The final sensor design uses only one current transformer for measuring unidirectional and bidirectional current. The toroid transformer has a primary that is the utility power to be measured passing through the center of the core and one secondary coil of up to 4000 turns. External clocking ensures continuous operation