System and method for controlling power to a heater

A method for controlling a heater, the method of comprising:

• selecting a state model control, as an operational state of the heater, from among a plurality of state model controls, wherein each of the plurality of state model controls comprises one or more operation settings for controlling the heater for the respective state model control, the one or more operation settings comprises a transition condition that causes a transition from the operational state to one other state model control, and the transition condition comprises one or more of a modification of a temperature set-point, a difference between the temperature set-point and a measured temperature exceeding a predefined threshold, a process time, or entry of a new load to be processed;
• measuring, by a controller, an electrical characteristic of the heater with a heater sensor, wherein the electrical characteristic includes at least one of an electric current and a voltage;
• determining, by the controller, a primary temperature based on the electrical characteristic of the heater;
• measuring, by the controller, an electrical response from a reference temperature sensor;
• determining, by the controller, a reference temperature of a reference area at the heater based on the electrical response from the reference temperature sensor;
• controlling power to the heater based on the selected operational state, the measured electrical characteristic, the reference temperature, the primary temperature or a combination thereof;
• and
• causing the transition to the one other state model control, as the operational state, wherein the transition to the one other state model control is based on the transition condition.

A method for controlling a heater, the method of comprising:

• selecting a state model control, as an operational state of the heater, from among a plurality of state model controls;
• measuring, by a controller, an electrical characteristic of the heater with a heater sensor, wherein the electrical characteristic includes at least one of an electric current and a voltage;
• determining, by the controller, a primary temperature of the heater based on the electrical characteristic;
• measuring, by the controller, an electrical response from a reference temperature sensor;
• determining, by the controller, a reference temperature of a reference area at the heater based on the electrical response from the reference sensor;
• and
• controlling power to the heater based on the primary temperature, the electrical characteristic, the reference temperature, the operational state, or a combination thereof, wherein controlling the power further comprises reducing the power to the heater in response to a difference between the reference temperature and the primary temperature being greater than a preset threshold.