System and Method for Calculation of Thermodynamic Properties from Anomalous Reference Data

A control system for controlling a vapor compression system having a multicomponent refrigerant mixture and actuators, comprising:

• an input interface configured to receive setpoints of the vapor compression system from a user input and measurement data from sensors arranged in the vapor compression system;
• a memory configured to store fluid property data of a fluid flowing in the vapor compression system and computer-executable programs including a thermofluid property calculator and an interpolation function calculator, where the thermofluid property calculator and interpolation function calculator are constructed by
• generating reference thermodynamic property data;
• identifying anomalous data points in the reference thermodynamic property data;
• cleaning the reference thermodynamic property data by one or a combination of eliminating the anomalous data points and replacing the anomalous data points with estimated values matching expected physical properties of the fluid to obtain cleaned anomaly-free thermodynamic property data;
• and
• calculating optimal coefficients with respect to the cleaned anomaly-free thermodynamic property data;
• and
• a processor configured to:
• compute, with respect to the setpoints, a pair of input thermofluid property variables from the measurement data or from the stored fluid property data;
• compute a third thermofluid property variable using the interpolation function calculator;
• compute derivatives of the third thermofluid property variable with respect to the pair of input thermofluid property variables using the interpolation function calculator;
• compute control data from the measurement data and the third thermofluid property variable and the derivatives of the third thermofluid property variable;
• and
• transmit, via an output interface, the computed control data including instructions that control the actuators operating the vapor compression system to the vapor compression system.