A DSB-SC demodulation technique for nonintrusive diagnostics of motor-operated valves

The health of motor-operated valves (MOVs) used in nuclear power plants may be monitored by analyzing the current drawn by its motor. This paper presents a technique for demodulating double sideband suppressed carrier modulation, an essential prerequisite for motor current analysis. Unlike conventional methods of demodulation, the technique does not require a synchronized sinusoid. The practical applicability of the technique is demonstrated by monitoring a nuclear-grade MOV through motor current analysis.