Development of a load-adaptive power regulation ultrasonic generator for wire harness welding

Ultrasonic wire harness welding is a technique that uses ultrasonic vibrations and welding pressure to bond multiple strands of wire together. This method is a crucial connection technology in industries such as automotive, electronics, and aerospace. It offers advantages including excellent electrical performance of weld joints, low power consumption, and a controllable welding process. By analyzing the operational characteristics of the transducer used in ultrasonic wire harness welding, the impedance behavior of the transducer under various load conditions is explored. Based on these insights, a new ultrasonic generator is designed with the ability to automatically adjust its power output according to the load near the parallel resonance frequency. The generator is capable of automatically sweeping to the optimal operating frequency and maintaining amplitude stability by adjusting its frequency. Wire harness welding experiments are carried out on wires with different cross-sectional areas, ranging from 2.5 mm² to 17.5 mm². The results show that the generator successfully completes the welding of copper wires up to 17.5 mm² with an output power of 2500 W.