Method for measuring the concentration of a gas component in a measurement gas

US9546989B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Ralf Bitter · Karlsruhe, DE
• Thomas Hankiewicz · Karlsruhe, DE
• Christoph Wolfgang Marquardt · Stockelsdorf, DE
• Jan Nygren · Västerås, SE
• Kai-Uwe Pleban · Blankenloch, DE
• Franz Steinbacher · Karlsruhe, DE

Key dates

• Filing date: Oct 1, 2014
• Grant date: Jan 17, 2017
• Expiry date: Jul 16, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/399
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for measuring the concentration of a gas component in a measurement gas using a gas analyzer comprises varying the wavelength of the light of a wavelength-tunable light source within periodically consecutive scan intervals for wavelength-dependent scanning of a gas component absorption line of interest. The method also comprises modulating the wavelength of the light of the wavelength-tunable light source with a frequency, guiding the modulated light through the measurement gas onto a detector and demodulating a measurement signal generated by the detector in the event of a harmonic of the frequency. The method further comprises producing a measurement result by fitting a desired curve to the profile of the demodulated measurement signal. A function orthogonal to the desired curve is provided, and an orthogonal component of the measurement result is produced by fitting the orthogonal function to the profile of the demodulated measurement signal.