DEVICE FOR NON-DISSIPATIVE MEASUREMENT OF CURRENT IN AN INDUCTIVE RESISTOR

摘要

The invention relates to a device for measuring current in an inductive resistor (12), which is connected in parallel on said inductive resistor, comprising two terminals A and B. The device comprises: a network (10) in parallel to the inductive resistor, connected to terminals A and B having a resistor R2 in a series with a resistor R1 in parallel with a capacitor C1; a voltage offset circuit (16) having a direct current voltage generator E connected in parallel to an offset resistor (Roffset) in a series with two parallel resistors R3 and R4, whereby the positive pole of said voltage source is connected to terminal B of the inductor; a temperature compensation circuit comprising a current source controlled as a function of temperature, one of the two terminals being connected to the negative pole of the generator E and the other terminal of the current source being connected to different points of the measuring device according to the direction of the variation of the current from the source as a function of temperature. Measurement of the voltage Vmes image of current 1 in the inductive resistor 12 is carried out between the common point between resistors R1, R2 of the network and the common point between the offset resistor (Roffset) and the two resistors R3 and R4. The invention can be applied to measurements of currents in inductive resistors of switched mode power supplies, converters designed to raise or lower voltage.