Back to results
US 12,605,197 B2Granted
Electrosurgical generator control using dynamic process variables
AssigneeIntuitive Surgical Operations, Inc.
InventorsForrest R. Lundstrom, Rajeshwari Srinivasan
Life of this patent
Estimating the term…
Abstract
An electrosurgical system includes an RF output stage configured to impart RF power between first and second electrodes; measurement circuitry measures current and voltage imparted between the first and second electrodes; a processing circuit calculates power and impedance, based upon the measured current and the measured voltage; the processing circuitry uses a proportional-integral-derivative control loop to control RF power imparted between the electrodes, based upon a selected one of the measured current, the measured voltage, calculated power, and the calculated impedance.
Claims17
An electrosurgical system comprising:
- a first electrode;
- a second electrode;
- an RF output stage configured to impart RF power between the first and second electrodes;
- current measurement circuitry configured to measure current, at a sampling rate, imparted between the first and second electrodes;
- voltage measurement circuitry configured to measure voltage, at the sampling rate, imparted between the first and second electrodes;
- a processing circuit configured to perform operations including:
- calculating power imparted between the first and second electrodes, based upon the measured current and the measured voltage;
- calculating impedance between the first and second electrodes, based upon the measured current and the measured voltage;
- using a proportional-integral-derivative control loop to control RF power imparted between the electrodes, based upon a selected one of the measured current, the measured voltage, and the calculated power;
- and
- selecting the one of the measured current, the measured voltage, and the calculated power, based at least in part upon the calculated impedance and two or more of a normalized representation of a measured current value, a normalized representation of a measured voltage value, and a normalized representation of a calculated power value.
8 more elements
An electrosurgical system comprising:
- a first electrode;
- a second electrode;
- an RF output stage configured to impart RF power between the first and second electrodes;
- current measurement circuitry configured to measure current, at a sampling rate, imparted between the first and second electrodes;
- voltage measurement circuitry configured to measure of voltage, at the sampling rate, imparted between the first and second electrodes;
- a processing circuit configured to perform operations including:
- calculating power imparted between the first and second electrodes, based upon the measured current and the measured voltage;
- calculating impedance between the first and second electrodes, based upon the measured current and the measured voltage;
- using a proportional-integral-derivative control loop to control RF power imparted between the electrodes, based upon a selected one of the measured current, the measured voltage, and the calculated power;
- and
- wherein selecting the one of the measured current, the measured voltage, and the calculated power includes:
- comparing the calculated impedance with a reference impedance;
- selecting one of a normalized current and a normalized voltage, based upon whether the calculated impedance is greater than or less than the reference impedance;
- and
- selecting between a normalized power and the selected one of the normalized current and the normalized voltage, based upon magnitudes of the normalized power and the selected one of the normalized current and the normalized voltage.
12 more elements
A method to control electrosurgical generator that imparts RF power between a first electrode and a second electrode, comprising:
- measuring current, at a sampling rate, imparted between the first and second electrodes;
- measuring voltage, at the sampling rate, imparted between the first and second electrodes;
- calculating power imparted between the first and second electrodes, based upon the measured current and the measured voltage;
- calculating impedance between the first and second electrodes, based upon the measured current and the measured voltage;
- using a proportional-integral-derivative control loop to control RF power imparted between the electrodes, based upon a selected one of the measured current, the measured voltage, and the calculated power;
- selecting the one of the measured current, the measured voltage, and the calculated power for use by the proportional-integral-derivative control loop, based at least in part upon the calculated impedance;
- and
- selecting the one of the measured current, the measured voltage, and the calculated power, based at least in part upon the calculated impedance and two or more of a normalized representation of a measured current value, a normalized representation of a measured voltage value, and a normalized representation of a calculated power value.
5 more elements
An electrosurgical system comprising:
- a first electrode;
- a second electrode;
- an RF output stage configured to impart RF power between the first and second electrodes;
- current measurement circuitry configured to measure current, at a sampling rate, imparted between the first and second electrodes;
- voltage measurement circuitry configured to measure of voltage, at the sampling rate, imparted between the first and second electrodes;
- a processing circuit configured to perform operations including:
- calculating power imparted between the first and second electrodes, based upon the measured current and the measured voltage;
- calculating impedance between the first and second electrodes, based upon the measured current and the measured voltage;
- using a proportional-integral-derivative control loop to control RF power imparted between the electrodes, based upon a selected one of the measured current, the measured voltage, and the calculated power;
- comparing the calculated impedance with a reference impedance;
- selecting one of a normalized current value and the normalized voltage value based upon the comparison;
- and
- comparing the selected one of the normalized current value and the normalized voltage value with the normalized power value.
10 more elements
Dependencies are inferred from the claim text.