Power Closed-Loop Control System for Electrosurgical Generators Based on Active Disturbance Rejection Control

In modern surgical procedures, electrosurgical generators(ESG) are very widely used energy devices that achieve tissue cutting and coagulation by delivering high-frequency voltage and current. During actual operations, the contact impedance between the electrode and tissue undergoes dynamic variations due to changes in tissue properties and environmental conditions, leading to output power fluctuations that may compromise surgical outcomes. Thus, to stabilize the output power and enhance surgical safety and performance, this paper proposes a high-frequency ESG system with closed-loop power control. A cascaded control architecture is adopted, in which the outer loop features an Active Disturbance Rejection Control(ADRC) based power controller, while the inner loop consists of a voltage-current dual-loop PID controller. The proposed energy generation circuit and control strategy are modeled and validated through MATLAB/Simulink environment. Results demonstrate that the system can effectively maintain stable output power under load disturbances and exhibits faster dynamic response and stronger disturbance rejection capability compared to conventional control methods.