Systems and methods for improving efficiency of electrosurgical generators

Patent metadata

Field	Value
Publication number	US-9839469-B2
Application number	US-201414320804-A
Country	US
Kind code	B2
Filing date	Jul 1, 2014
Priority date	Sep 24, 2013
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

An electrosurgical generator is presented including a radio frequency (RF) amplifier coupled to an electrical energy source and configured to generate electrosurgical energy, the RF amplifier including an inverter configured to convert a direct current (DC) to an alternating current (AC), and a plurality of sensors configured to sense voltage and current of the generated electrosurgical energy. The electrosurgical generator further includes a controller coupled to the RF amplifier and the plurality of sensors. The electrosurgical may be further configured to determine a power level based on the sensed voltage and the sensed current, determine an efficiency of the electrosurgical generator, and insert a predetermined integer number of off cycles when the efficiency of the electrosurgical generator reaches a threshold power efficiency.

First claim

The invention claimed is:

1. An electrosurgical generator comprising:
a radio frequency (RF) amplifier having an inverter configured to convert a direct current (DC) to an alternating current (AC);
a plurality of sensors configured to sense voltage and current of generated electrosurgical energy; and
a controller coupled to the RF amplifier and the plurality of sensors;
wherein the controller is configured to:
generate a control signal for controlling the inverter;
determine a power level based on sensed voltage and sensed current;
determine a power efficiency of the inverter based on the determined power level; and
drop a predetermined integer number of cycles from the control signal to form cycles having no pulse signals when the power efficiency of the inverter reaches a threshold power efficiency, the predetermined integer number of the cycles being dropped from the control signal at random times.

2. The electrosurgical generator according to claim 1 , wherein a duty cycle is varied to facilitate maintenance of a desired power efficiency.

3. The electrosurgical generator according to claim 1 , wherein an average power is maintained regardless of how many cycles of the control signal are dropped.

4. The electrosurgical generator according to claim 1 , wherein the controller is further configured to switch from a continuous wave mode to a pulsed wave mode.

5. The electrosurgical generator according to claim 1 , wherein a duty cycle is determined to maintain the determined power level at a desired power level.

6. The electrosurgical generator according to claim 5 , wherein the duty cycle is varied to maintain a desired power efficiency.

7. The electrosurgical generator according to claim 1 , wherein a pulse width is determined to maintain the determined power level at a desired power level.

8. The electrosurgical generator according to claim 7 , wherein the pulse width is varied to maintain a desired power efficiency.

9. A method of improving efficiency of an electrosurgical generator, the method comprising:
sensing voltage and current generated by an inverter of the electrosurgical generator;
generating a control signal for controlling the inverter;
determining a power level based on sensed voltage and sensed current;
determining a power efficiency of the inverter of the electrosurgical generator based on the determined power level; and
dropping a predetermined integer number of cycles from the control signal to form cycles having no pulse signals when the power efficiency of the inverter reaches a threshold power efficiency, the predetermined integer number of the cycles being dropped from the control signal at random times.

10. The method according to claim 9 , further comprising varying a duty cycle to facilitate maintenance of a desired power efficiency.

11. The method according to claim 9 , further comprising maintaining an average power regardless of how many cycles of the control signal are dropped.

12. The method according to claim 9 , further comprising switching from a continuous wave mode to a pulsed wave mode.

13. The method according to claim 9 , further comprising determining a duty cycle to maintain the determined power level at a desired power level.

14. The method according to claim 13 , further comprising varying the duty cycle to maintain a desired power efficiency.

15. The method according to claim 9 , further comprising determining a pulse width to maintain the determined power level at a desired power level.

16. The method according to claim 15 , further comprising varying the pulse width to maintain a desired power efficiency.

Assignees

• Covidien Lp

Inventors

• Gilbert James A
• Johnston Mark A
• Mattmiller Aaron
• Johnson Joshua H

Classifications

• A61B2018/1266

  with DC current output · CPC title

• A61B2018/00892

  Voltage · CPC title

• A61B2018/00875

  Resistance or impedance · CPC title

• A61B2018/00827

  Current · CPC title

• A61B2018/00779

  Power or energy · CPC title