Development of a Cavitation Detection Technique for Inverter-Driven Pumps Using Motor Current Signals

Simple and cost-effective methods for cavitation detection are essential for stable operation of water pump systems. This paper reviews the characteristics of motor current signals under cavitation conditions and propose a cavitation detection technique for inverter-driven pumps based on these signals. Experimental observations show that the spectral “foot” around the fundamental harmonic in the power spectral density (PSD) of the motor current signals increases during cavitation. Based on this observation, we define an evaluation value metric that quantifies this feature for cavitation detection.