RF generator system for surgical vessel sealing

• US 10,342,599 B2
• Filed: 04/11/2017
• Issued: 07/09/2019
• Est. Priority Date: 10/22/2010
• Status: Active Grant

• Current Assignee: Bolder Surgical, LLC (Hologic Incorporated)
• Original Assignee: JustRight Surgical, LLC (Hologic Incorporated)
• Inventors: Ross, David, Helfer, Joel
• Primary Examiner(s): Porter, Allen
• Application Number:
  US15/484,645
• Publication Number:
  US 20170281258A1
• Time in Patent Office: 819 Days
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00779 Power or energy
• CPC Class Codes: A61B 2018/00827 Current
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/00892 Voltage
• CPC Class Codes: H02M 7/48 using discharge tubes with control electrode or semiconductor devices with control electrode
• CPC Class Codes: H02M 7/539 with automatic control of output wave form or frequency H02M7/5375 - H02M7/5387 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

Systems, methods, and apparatus for providing power to an electrosurgical instrument. A method of providing power to an electrosurgical instrument includes generating a non-sinusoidal driving voltage having a substantially constant driving frequency; providing the non-sinusoidal driving voltage to a series LC circuit having a resonant frequency of substantially twice the substantially constant driving frequency and configured to present an impedance that limits current spikes and voltage transient spikes during load fluctuations; generating a quasi-sinusoidal current in the series LC circuit from the non-sinusoidal driving voltage; and providing the quasi-sinusoidal current to an electrical output, wherein the electrical output is configured for coupling to an electrical input of a bipolar tissue-sealing surgical instrument.

Claims

1. A method of providing power for an electrosurgical instrument comprising:

generating a non-sinusoidal driving voltage having a driving frequency;

providing the non-sinusoidal driving voltage to a series LC circuit having a resonant frequency different from the driving frequency, the series LC circuit configured to present an impedance to limit current;

storing energy in the series LC circuit during a resonant cycle of the series LC circuit;

during the resonant cycle of the series LC circuit, discharging substantially all of the energy stored in the series LC circuit to a power provider comprising a DC bus; and

generating a quasi-sinusoidal current in the series LC circuit from the non-sinusoidal driving voltage.

2. The method of claim 1, wherein

the limiting current comprises presenting an impedance to the quasi-sinusoidal current in the LC circuit.

3. The method of claim 1, wherein the non-sinusoidal driving voltage is at least one of a pulsed waveform or a waveform having a square wave shape and a 50 percent duty cycle.

4. The method of claim 1, wherein the series LC circuit has a resonant frequency of substantially twice the substantially constant driving frequency.

5. The method of claim 1, wherein

the non-sinusoidal driving voltage is a waveform having a square wave shape and a 50 percent duty cycle;

and

the discharging substantially all of the energy stored in the series LC circuit comprises discharging so that the quasi-sinusoidal current in the series LC circuit approaches 0 amperes during a switching of the pulsed waveform.

6. The method of claim 5, wherein

the waveform has a square wave shape;

and

the discharging substantially all of the energy stored in the series LC circuit comprises discharging the energy to the power provider during a period of time, the period of time corresponding to a second half of a resonant cycle of the LC circuit.

7. The method of claim 1, wherein

the non-sinusoidal driving voltage is generated by the power provider.

8. The method of claim 7, further comprising

resupplying the substantially all of the energy back to the series LC circuit.

9. The method of claim 1, further comprising

resupplying the substantially all of the energy back to the series LC circuit.

10. A power supply for an electrosurgical instrument comprising:

a power provider having a DC bus and configured to generate a non-sinusoidal voltage at a driving frequency; and

a series LC circuit configured to receive the non-sinusoidal voltage and provide a quasi-sinusoidal current, the series LC circuit having a resonant frequency that is different from the driving frequency, the series LC circuit configured to

(a) present an impedance to limit current;

(b) store energy during a resonant cycle of the series LC circuit;

(c) during the resonant cycle, discharge substantially all of the energy stored in the series LC circuit to the power provider; and

(d) generate a quasi-sinusoidal current from the non-sinusoidal driving voltage.

11. The power supply of claim 10, wherein the power provider is configured to generate one of a pulsed waveform or a waveform having a square wave shape and a 50 percent duty cycle.

12. The power supply of claim 10, wherein

the power provider includes a power source, an h-bridge, and a buck-boost converter configured to provide DC power to the h-bridge;

and

the DC power has an amplitude configured to control a variable amplitude of the buck-boost converter.

13. The power supply of claim 12, wherein the h-bridge is configured to receive DC power from the power source, and provide a pulsed voltage to the series LC circuit at the driving frequency.

14. The power supply of claim 13, further configured to

pass energy from the power source to the h-bridge and to the series LC circuit during a first half of each pulse of the square wave shape;

and

pass energy from the series LC circuit to the h-bridge to the power source during a second half of each pulse of the square wave shape.

15. The power supply of claim 12, wherein the power source comprises a DC bus.

16. The power supply of claim 10, wherein

the series LC circuit is configured to discharge the substantially all of the energy to the power provider during a period of time, the period of time corresponding to a second half of a resonant cycle of the LC circuit.

17. The power supply of claim 10, wherein

the discharge substantially all of the energy stored in the series LC circuit comprises returning the energy to the power provider.

18. The power supply of claim 17, wherein

the power provider is configured to resupply the substantially all of the energy back to the series LC circuit.

19. The power supply of claim 10, wherein the power provider is configured to absorb substantially all energy stored in the series LC circuit during a period of time once per resonant cycle of the series LC circuit and to resupply the substantially all energy back to the series LC circuit.