Current measurement device having floating amplifier for use in accurate determination of the voltage across a shunt in series with a noise voltage used in powering a three-phase motor for driving power steering in motor vehicles

摘要

Device comprises a shunt resistance (8) mounted in series with the supply voltage with an amplifier (15) to amplify the shunt signal. The amplifier is a floating amplifier and has means (C1, C2, D1, D2) for supplying the amplifier with a voltage which follows the voltage supplied to the shunt. An Independent claim is made for a procedure for measuring the current on a noise voltage supply line with an amplification stage for amplification of the voltage between input terminals (12) and output terminals (13) of a shunt (8) using a floating amplifier (15).