Virtual in-situ calibration method in building systems
Date of this Version
Y. Yu*, H. Li. (2015) "Virtual in-situ Calibration Method in Building Systems". Automation in Construction. 2015, Vol. 59: 59-67.
Sensors play an important role in guiding building systems to achieve desired operation and efﬁciency. However, sensors are subject to continuous degradation and failures over time. Although a periodical calibration is needed, it is exceptionally difﬁcult and/or impractical to many sensors with a conventional manual approach. Uncalibrated problematic sensors could signiﬁcantly compromise the systems' performance and lead to unintended loss of energy efﬁciency in buildings. We propose a methodology, termed virtual in-situ calibration, to solve this critical issue. It is developed by mathematically extracting the characteristics of essential aspects involved in a calibration, including the environment assessment, benchmark establishment, and uncertainty quantiﬁcation. A case study of a supply air temperature sensor in rooftop units illustrates the implementation process; the erratic uncertainty is reduced from ±19.2 °C to ±0.7 °C after the virtual in-situ calibration. The calibration method can be implemented online to signiﬁcantly improve the reliability of sensor networks in buildings.