GaN-HEMT Based Very-High-Frequency AC Power Supply for Electrosurgery

To power electrosurgery, a very-high-frequency AC inverter (VHFI) is required. In this paper, a full-bridge based VHFI is proposed to enable electrosurgery. Its high-frequency output generating mechanism and the high order filter design are explained. To check the feasibility of the proposed VHFI, a 300 W Gallium Nitride High Electron Mobility Transistors (GaN HEMT) based experimental setup with 390 kHz output frequency, has been designed and implemented. Experimental efficiency and total harmonic distortion (THD) results are graphed for pure cutting mode. It turns out that maximum THD is less than 2.5% for the proposed VHFI. Further, recurring and burst experiment results are provided for blend cutting mode and coagulation mode, respectively. The experiment results show that the proposed VHFI has extreme fast-responding time for both blend cutting and coagulation mode, and crest factor is about 21 for coagulation mode. All experiment results together validate the feasibility of the proposed VHFI and also verify its capability of supporting different load values under different clinical modes.