ELECTROSURGICAL GENERATOR CONTROLLER FOR REGULATION OF ELECTROSURGICAL GENERATOR OUTPUT POWER

摘要

An electrosurgical generator may reduce unintended tissue damage by improving regulation of output power. The electrosurgical generator may control the power during a cycle, and react to a change in power if arcing occurs. Voltage sources, especially, demonstrate the tendency to have large, uncontrolled power excursions during normal electrosurgical use. The magnitude of the power excursions may be dependent on various factors. An exemplary electrosurgical generator control scheme reduces or minimizes the thermal spread by accurately supplying the specified power within a few cycles. Additionally, fast and accurate regulation provided by the constant voltage mode reduces or minimizes unintentional tissue charring. Thus, reduced thermal spread and charring should result in better surgical outcomes by reducing scarring and decreasing healing times. An electrosurgical generator controller may be configured to control both a DC-DC buck converter and a DC-AC boost inverter based in part on electrical parameters of the electrosurgical generator.

主权项

1. An electrosurgical generator comprising:
a DC-DC buck converter configured to receive input power and to receive a first driver signal; a DC-AC boost inverter configured to receive a second driver signal, separate from the first driver signal; an inductor in communication with the DC-DC buck converter and the DC-AC boost inverter; a transformer having a primary winding and a secondary winding, wherein the transformer is configured to transmit output power to a load; wherein the DC-AC boost inverter is configured to receive an input from the inductor and transfer AC power to the primary winding of the transformer; and an electrosurgical generator (ESG) controller configured to control both the DC-DC buck converter and the DC-AC boost inverter; wherein the ESG controller comprises:
a current-mode controller configured to compare an inductor current iL(t) through the inductor to a control current limit iC, and wherein the current-mode controller is configured to generate a current-mode controller signal for use during either a constant current operating mode of the ESG or a constant power operating mode of the ESG;a voltage-mode controller configured to compare an output voltage vout(t) with a reference voltage Vmax, and wherein the voltage-mode controller is configured to generate a voltage-mode controller signal for use during a constant voltage operating mode of the electrosurgical generator;a mode selector configured to compare the inductor current iL(t) and the output voltage vout(t) to respective current limits and voltage limits and to generate an operating mode indicator; andsteering logic configured to receive: the operating mode indicator, and steering logic input signals; wherein the steering logic input signals comprise: the current-mode controller signal having a first duty cycle d1(t), the voltage-mode controller signal having a second duty cycle d2(t), a third signal having a fixed duty cycle d3, and a fourth signal having a fixed duty d4; wherein, based on the operating mode indicator, the steering logic is further configured to selectively pass one of the steering logic input signals to the first driver signal, and another of steering logic input signals to the second driver signal, thereby selecting an operating mode of the ESG from one of the constant current operating mode of the ESG, the constant power operating mode of the ESG, or the constant voltage operating mode of the ESG.