Development of AgeAlert: A Predictive Maintenance Sensor for Electrical Insulation Systems in Nuclear Power Applications

Component failures resulting from degradation within insulation systems represents a significant contribution to reliability and cost issues facing the nuclear power industry. For example, the Electric Power Research Institute found that 37% of motor failures were due to winding failures, many of which involve failure of the insulation system. Although a number of visual, tactile, or electrical tests exist for detecting and locating insulation problems, current methods are complex and expensive, and require considerable expertise, or they are subjective and require shutdowns and/or disassembly. This project will develop a new sensing technology, called AgeAlert, which will provide the first direct measurement of insulation degradation, both in situ and in real time. In this approach, a tiny low-cost sensor ¿ installed in the windings of a motor, generator, or transformer ¿ responds to actual environmental conditions in the motor and accurately correlates to insulation degradation. Because AgeAlert sensors are conductive composites made with the same insulation resin of the insulation being monitored, the sensors respond in exactly the same manner, and under exactly the same conditions, as the insulation itself. Phase I developed prototype AgeAlert sensors and demonstrated feasibility by accurately tracking the insulation in a reactor coolant pump motor. In Phase II, expanded aging trials will be conducted on additional insulation systems in thermal, radiation, and humidity environments. The prototype sensor will be tested in a realistic nuclear component test bed, and an integrated system design will be completed for the incorporation of AgeAlert sensors in plant-wide condition-monitoring systems. Commercial Applications and Other Benefits as described by the awardee: The AgeAlert technology should reduce the cost of screening individual electrical components for insulation deterioration and provide advance warning of insulation degradation. In addition to the application to the nuclear power industry, the sensors should be applicable to degradation monitoring of virtually any polymeric material, opening possibilities for use in wire and cable systems, seals and gaskets, hybrid automobile motor/generators, tires, belts, and aerospace composite structures.