US 2026/0147022 A1 · Measuring an Electrical Current Using Two Optical Current Transformers

Abstract

The invention relates to a method for measuring an electrical current (I). In the method, measurement signals (A) dependent on the current (I) are detected multiple times by each of at least two optical current transformers (5, 7), wherein the current transformers (5, 7) have differing unambiguous ranges (E1 to E4) in which the measurement signal (A) detected by the relevant current transformer (5, 7) monotonously increases or decreases as the current (I) increases. A sign value is continually determined for each current transformer (5, 7), the sign value indicating the sign of the first derivative of the measurement signal (A) detected by the current transformer (5, 7) with respect to the current (I). A modified unambiguous range (E1 to E4) of the current transformer (5, 7) is associated with the measurement signals (A) from a current transformer (5, 7) if the sign value determined for this current transformer (5, 7) changes and the sign value determined for at least one other current transformer (5, 7) does not change. The amperage of the electrical current (I) is determined from the measurement signals (A) from at least one current transformer (5, 7).

Claims12

Dependent claims

A method comprising:

repeatedly detecting one or more measurement signals dependent on an electrical current using at least two optical current transformers, wherein;
the optical current transformers have differing unambiguous ranges in which the measurement signals detected by each respective optical current transformer monotonously increase or decrease as the electrical current increases;
continually determining a sign value for each optical current transformer, the sign value indicating a sign of a first derivative of an associated measurement signal of the measurement signals with respect to the electrical current as detected by the respective optical current transformer;
associating a modified unambiguous range of each optical current transformer with a subset of measurement signals of the measurement signals associated with the corresponding optical current transformer if the sign value determined for this optical current transformer changes and the sign value determined for at least one other optical current transformer does not change;
and
determining an amperage of the electrical current from the measurement signals of at least one optical current transformer.

3 more elements

A measuring device for measuring an electrical current, the measuring device comprising:

at least two optical current transformers which are each configured to repeatedly detect one or more measurement signals dependent on the electrical current, wherein the optical current transformers have differing unambiguous ranges in which the measurement signals detected by the respective optical current transformer monotonously increases or decrease as the electrical current increases;
and
an evaluation unit, which is configured to:
continually determine a sign value for each optical current transformer, the sign value indicating a sign of a first derivative of an associated measurement signal of the measurement signals with respect to the electrical current as detected by the respective optical current transformer;
assign a modified unambiguous range of each optical current transformer to a subset of measurement signals of the measurement signals associated with the corresponding optical current transformer if the sign value determined for this optical current transformer changes and the sign value determined for at least one other optical current transformer does not change;
and
determine an amperage of the electrical current from the measurement signals of at least one optical current transformer.

4 more elements

Dependencies are inferred from the claim text.

Measuring an Electrical Current Using Two Optical Current Transformers

Life of this patent

Measuring an Electrical Current Using Two Optical Current Transformers

Life of this patent

Abstract

Claims12