Systems and methods for real-time steam quality estimation

A system for determining a steam quality estimate of a steam generator, the system comprising:

• an input that is configured to obtain raw measurement values for process variables of the steam generator from sensors coupled to the steam generator;
• a steam quality sensor that is configured to receive the raw measurement values for the steam generator and slow-rate steam quality samples in order to determine a steam quality estimate, the steam quality sensor including:
• a measurement module that is configured to receive the raw measurement values and determine model input values and a robustness index;
• an estimator module that is configured to determine a raw steam quality estimate using the model input values and a model that is selected from several models depending on reliability of a corresponding combination of the raw measurements by:
• selecting a first model when a differential pressure of an individual pass of the steam generator is determined to be reliable;
• selecting a second model when the differential pressure of an individual pass of the steam generator is determined to be unreliable and when a flow rate of an inlet gas of the steam generator and a stack temperature of waste gas of the steam generator are determined to be reliable;
• selecting a third model when the differential pressure of an individual pass of the steam generator, a flow rate of an inlet gas of the steam generator and a stack temperature of waste gas of the steam generator are all unreliable;
• and
• determining the raw steam quality estimate as a function of the selected model;
• and
• a corrector module that is configured to determine the steam quality estimate using the raw steam quality estimate, the robustness index, and the slow-rate steam quality samples;
• an output that is coupled to the steam quality sensor and is configured to receive the steam quality estimate;
• and
• a control unit that is coupled to the output, the control unit being configured to receive the steam quality estimate and generate a control signal using the steam quality estimate to control at least one control input of the steam generator to maintain the steam quality of the steam generated by the steam generator within a desired range.