Method and apparatus for controlling a temperature-controlled probe

A method for controlling a power output of a probe connected to a system including controller circuitry to maintain a target temperature, the probe having a thermal element and a temperature sensor, the temperature sensor providing a sensed temperature, comprising the steps of:

• providing, in a memory, at least one set of probe settings including at least one gain parameter and corresponding to predetermined operating characteristics for a particular probe, the at least one gain parameter including a set specific proportional gain factor, a set specific integral gain factor and a set specific derivative gain factor;
• receiving the target temperature;
• receiving a first probe setting corresponding to a desired set of operating characteristics for a probe;
• selecting a set from the at least one set of probe settings in response to the first probe setting;
• receiving a sensed temperature;
• generating an error signal by comparing the sensed temperature to the target temperature;
• generating a proportional signal by multiplying the error signal by the selected set specific proportional gain factor;
• generating an integral signal by integrating the error signal and multiplying the integrated error signal by the selected set specific integral gain factor;
• generating a derivative signal by comparing the sensed temperature to a previous sensed temperature and applying a derivative function to generate an intermediate signal and multiplying the intermediate signal by the selected set specific derivative gain factor;
• summing the proportional signal, the integral signal and the derivative signal to generate the output control signal;
• controlling an amount of power output to the thermal element in response to the output control signal to maintain the target temperature;
• determining an antiwindup difference by subtracting a maximum predetermined output control value from the output control signal;
• generating an antiwindup adjustment signal by multiplying the antiwindup difference by an antiwindup gain factor;
• and
• generating a modified error signal by subtracting the antiwindup adjustment signal from the error signal, wherein said step of generating the integral signal integrates the modified error signal by the integral gain factor.

A system for controlling the power output of a probe connected to the system to maintain a temperature, the probe having a thermal element, and a temperature sensor providing a sensed temperature, comprising:

• a processor;
• and
• a memory storing at least one set of probe settings, the at least one set including at least one gain parameter and corresponding to a predetermined operating characteristics for a particular probe,
• the memory also storing instructions that cause the processor to:
• receive a target temperature value;
• receive a first probe setting corresponding to a desired set of operating characteristics for a probe;
• select a set of the probe settings in response to the first probe setting;
• generate an error value by comparing the sensed temperature value to the target temperature value;
• and
• determine an output control value by applying a control function to the error value, the control function using the at least one gain parameter from the selected set whereby an amount of power is outputted to the thermal element in response to the output control value to maintain the temperature.

A computer program product for controlling a power level of a probe connected to a medical device computer system, the computer program product for use in conjunction with the computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising:

• at least one set of probe settings including at least one gain parameter and corresponding to a predetermined operating characteristics for a particular probe;
• a first set of instructions that receive a target temperature value;
• a second set of instructions that receive a first probe setting corresponding to a desired set of operating characteristics for a probe;
• a third set of instructions that select a set from the at least one set of probe settings in response to the first probe setting;
• a fourth set of instructions that receive a sensed temperature value;
• a fifth set of instructions that generate an error value by comparing the sensed temperature value to the target temperature value;
• a sixth set of instructions that determine an output control value by applying a control function to the error value, the control function using the at least one gain parameter from the selected set;
• and
• a seventh set of instructions that cause an amount of power to be outputted to a thermal element in response to the output control value.