Combined Feedforward Duty Cycle Predictive and Feedback Power Control for Electrosurgical Generator

Electrosurgical generator (ESG) is a medical equipment widely used in surgery, and its power needs to be precisely regulated to achieve a specific therapeutic effect. This article presents a combined feedforward duty cycle predictive and feedback power control (FDCPFP) method, which can achieve fast transient response to load resistance variation. A small-signal model of the proposed control method is established, and the closed-loop transfer function is derived to judge the power tracking performance when the load resistance changes. A 200W prototype was built in the laboratory, and the experimental results demonstrate that the proposed control method can diminish power fluctuation during the load resistance transition.