Process and device for measuring an alternating electric current with temperature compensation

US5847560A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Thomas Bosselmann · Erlangen, DE
• Peter Menke · Erlangen, DE

Key dates

• Filing date: Mar 7, 1997
• Grant date: Dec 8, 1998
• Expiry date: Mar 7, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R15/246
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Linearly polarized measuring light is broken down into two differently polarized component light signals in an analyzer after passing through a Faraday sensor device. The intensity of the corresponding electric intensity signals is normalized by dividing the respective alternating signal component by the respective direct signal component. From the two normalized intensity signals S1 and S2, a measuring signal is derived according to the formula: EQU S=(2.multidot.S1.multidot.S2)/((S2-S1)+K.multidot.(S1+S2)) where cos(2.theta.+2.eta.)=-2/(3K) and sin(2.theta.-2.eta.)=1 are valid for a correction factor K, an injection angle .eta. between the plane of polarization of the injected measuring light to a natural axis of the linear birefringence in the sensor device and a exit angle .theta. between this natural axis and a natural axis of the analyzer.