The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 25, 2017
Filed:
May. 10, 2011
Xiangxun Chen, Beijing, CN;
Jianbo Guo, Beijing, CN;
Ping Jing, Beijing, CN;
Shuo Chen, Beijing, CN;
Shujie Yin, Beijing, CN;
Zhanyuan Liu, Beijing, CN;
Xiangxun Chen, Beijing, CN;
Jianbo Guo, Beijing, CN;
Ping Jing, Beijing, CN;
Shuo Chen, Beijing, CN;
Shujie Yin, Beijing, CN;
Zhanyuan Liu, Beijing, CN;
China Electric Power Research Institute, Beijing, CN;
Abstract
This present inversion provides a digital closed-loop fiber optical current sensor. The modulation signal of the optical wave 'phase modulator' of the fiber optical current sensor system is modulation square wave, signal processing system extracts any harmonic wave of the photoelectric converter output modulation square waves, and extracts the measured current information from it. The preamplifier of signal processing system is transimpedance amplifier TIA, the bandwidth is extracted 1/650 instantaneous amplitude square wave directly from the modulation square wave (existing), thus the thermal noise of the preamplifier output and shot noise level is reduced to the existing technology of below 1/650; the current-voltage gain of transimpedance amplifier TIA does not depend on the feedback network resistance, thus it can have high current-voltage conversion gain and use low resistance in the feedback network TIA at the same time. So it can reduce resistance thermal noise to negligible that is accounted for a large proportion of TIA output noise.