High-resolution physically-windowed sensors for power electronics applications

This paper presents a high-resolution, physically-windowed sensor architecture that is well-suited for energy scorekeeping and diagnostic applications. The sensor can track a large-scale main signal while capturing small-scale variations. The prototype system measures a small current signal using a closed-loop Hall sensor, and extends the range by driving a compensation current through an auxiliary winding. The system combines the compensation command and the sampled output of the residual sensor to reconstruct the input signal. Results show that the prototype can measure both dc and ac currents with 10 mA resolution over a 160 A current range.