INSTRUMENT POWER CONTROLLER AND METHOD FOR ADAPTIVELY PROVIDING AN OUTPUT VOLTAGE AND AN OUTPUT CURRENT THAT TOGETHER MAINTAIN A SUBSTANTIALLY CONSTANT ELECTRICAL OUTPUT POWER

摘要

An instrument power controller (120) for adaptively providing an outputvoltage V O and an output current I O thattogether maintain a substantially constant electrical output power P O isprovided. The controller (120) includes inputs (121) forreceiving an input power P I, outputs (122) for providing the substantiallyconstant output power P O to a variable impedance load L,and a communication path (126) for receiving a load voltage V L. Theinstrument power controller (120) is configured to determinean input voltage V I and an input current I I, determine an effectiveresistance R L of the load L and set the output voltage V O andthe output current I O based on the input voltage V I, the input current I I,and the effective resistance R L. The output voltage V O issubstantially independent from the input voltage V I. The output voltage V Oand the output current I O are varied to maximize a loadpower P L while maintaining the substantially constant electrical output powerP O.