Method and device for measuring an alternating electric quantity with temperature compensation by fitting

US5895912A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

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

Key dates

• Filing date: Apr 4, 1997
• Grant date: Apr 20, 1999
• Expiry date: Apr 4, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R15/247
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Polarized measuring light is coupled into a sensor device and, after passing through the sensor device, is decomposed in an analyzer into two differently, linearly polarized partial light signals. The corresponding electric intensity signals are intensity-normalized by dividing their respective AC signal component by their respective DC signal component. From the two intensity-normalized signals S1 and S2, a temperature-compensated measured signal M is derived in accordance with the two equations S1=f1(T)*M and S2=f2(T)*M. The functions f1(T) and f2(T) are predetermined by particular linear, quadratic, or exponential fit-functions of the temperature T. In particular, in the case of linear fit-functions f1(T) and f2(T), the measured signal is yielded as M=A*S1+B*S2.