Temperature compensation of a contactless coil-based path measurement system, in which a compensation voltage is applied to the coil or coil-system to ensure a constant current flows in it and path measurements are accurate

摘要

Method for temperature compensation of a contactless, inductive or Eddy current type path measurement system. Said system has at least one coil that acts as a sensor with an alternating current supply to it. The current through the coil is maintained at a constant value even when the temperature of the coil varies. To achieve this the voltage drop across a series resistance is measured using an amplifier circuit and then used as a control value for a constant coil current. An Independent claim is included for a corresponding electric circuit for implementation of the method.