Output error of converse piezoelectric fiber voltage sensor caused by optical fiber factors

Abstract

In fiber voltage sensor, imperfect fiber splicing angle and length difference between the sensing fiber and the compensating fiber usually influence the system output performance. This article established the mathematical model of the system output error using the Jones matrix and analyzed the relationship between the system output error and the above two error factors, respectively. The results show that the angle error of 90° splice has a significant influence on the system output, and the tolerance of angle error varies with different test voltages. When the test voltage is higher than 6 kV, if the expected system error is less than 0.02%, the splicing angle error should be less than 0.15°. Additionally, the length difference also has a significant influence on the system output accuracy. The length difference between sensing fiber and compensating fiber should be less than 1 µm when the test voltage is 110 kV so that the system can meet the accuracy requirements of IEC 0.2s. This research provides a reference for the development of fiber voltage sensor based on the converse piezoelectric effect and also provides a basis for the design of intelligent power detection robot system.

Opto-mechanical modeling and experimental implementation of an FBG-based piezoelectric bimorph actuator for high voltage sensing applications

“…A total optical-power sensitivity of 0.03867 mW/kV was achieved for the proposed set-up. A long term operation analysis was executed to determine sensor stability, during the first stages of operation the uncertainty in measured power only drifted to a maximum of 0.4%, very close to commercial high-accuracy potential transformer sensors of 0.1% (Yang et al, 2019), and the accuracy of the sensor was found to be of 0.013% of input optical power. However, after 10 h of continuous operation, the setup experienced some deviations in measured power that showed a maximum drift in received optical power of 3.03%.…”

“…This deviation may be related to the temperature rise of the bimorph surface during operation, that was not totally compensated in the current set-up, as well as some possible light-source stability issues, voltage source excitation, among others. For the implemented case, this uncertainty limited the accuracy of the proposed sensor to be about 5.6 kV 6 30 V, which still offers a relatively good resolution for potentially protective and insulation coordination in high voltage systems (Yang et al, 2019).…”

“…Advantages that optical, and specifically fiber-based sensors, offer to high voltage electric systems include: light weight, high dielectric strength, and electromagnetic interference immunity, among others (Bohnert et al, 2005;Chen et al, 2011;Lee, 2003). These properties make optical sensors very attractive to new developments and implementations for power delivery, measurement and control operations in power systems and high voltage situations (Fusiek et al, 2012;Yang et al, 2019). Potential instrument transformers, namely current and voltage instrument transformers, are one of the most critical elements in measurement and control of electric power in substations, generation plants, transmission, and distribution systems (Sawa et al, 1990).…”