Securable Networks for Nonintrusive Sensor Fusion

Fault detection and diagnostics (FDD) and energy scorekeeping for power systems can be performed nonintrusively with current and voltage sensing at a utility panel. The key problem remains that some important electromechanical behavior, including vibration and acoustic signatures, cannot be easily detected in the power stream, and a small set of additional sensors may be necessary for automated analysis. A nonintrusive power monitor can serve as a central point for collating or “fusing” sensor data from remote sensors, providing a correlated picture of remote sensor data with power consumption. A local, physically secured intranet eases the cybersecurity challenge of a facility by avoiding conventional Internet of Things (IoT) solutions. This article demonstrates a Wi-Fi-based implementation of an FDD intranet on the microgrids of several marine vessels. Connectivity tests presented in this work show that Wi-Fi is a viable link medium for an FDD intranet in shipboard environments. In addition, this work demonstrates the ability to track pump pressure, air conditioning (A/C) compressor loading state, and fan imbalance using fused nonintrusive sensing. Cyclostationary signal processing techniques identified a faulty relief valve in a vacuum pump that evaded traditional analysis. Four sensor network strategies are presented for these scenarios. This work concludes that synchronized power and vibration data provide complementary fault detection ability.