Hysteresis effects in high‐power ultrasonic transducers

摘要: It is well known that ultrasonic piezoelectric transducers can be difficult to drive at high power levels. Transducers usually have Qs, which implies a narrow driving bandwidth and characteristics may change with temperature, component wear, or variations in the load. Some method of feedback control required lock onto optimum transducer frequency. Small‐signal parameters are used design both amplifier matching system. In this work we measured several sandwich coupled water significant levels (50–250 V) by measuring current, voltage, phase. Increasing level shows decrease operating‐point addition, Q admittance point decreases. This creates practical problem as done on basis small‐signal values will inaccurate. also results an abrupt transition lower impedance value after onset cavitation. Decreasing shown exhibit hysteresis effect thought due persistence gas bubbles liquid.