In ultrasonic welding, the generator is the power supply that produces the high-frequency electrical energy needed to drive the transducer and convert it into ultrasonic mechanical vibrations. The generator converts the input line power into a high-frequency AC signal that is sent to the transducer, which in turn produces high-frequency mechanical vibrations. The generator provides control over the output amplitude, frequency, and duration of the ultrasonic vibrations, which can be adjusted based on the specific requirements of the welding process. The generator also provides safety features to protect the system from overheating or overload conditions.