Pump Condition Monitoring Using Self-Powered Wireless Sensors

Fluid pumps are critical elements in many industrial, commercial, and marine systems. Continuous monitoring of pump systems is the most effective technique to insure efficient operation, help prevent unexpected pump failures, reduce repair costs and downtime, and provide early warning to avoid loss of pumped fluid. Wireless sensors are gaining increasing interest for equipment monitoring and surveillance applications. An alternative to battery-powered sensor nodes is the use of energy scavenged from the environment that may be converted and stored as needed to power remote sensors, processors, and RF communications. This article describes the development of a prototype, self-powered, wireless sensor node. Power is extracted from vibration using tuned piezoelectric elements. The self-powered sensor node performs local processing and transmits analytic results or raw sampled data to a central node for database storage and more extensive diagnostics and prognostics. The frequency of data analysis and transmission is a function of the available generated power. Examples are presented from a laboratory pump system and from a recent shipboard trial. Power efficiencies obtained are reported along with opportunities for adaptive power scavenging and dynamically optimizing power consumption.