Comparison Analysis of FIR, ARX, ARMAX by Least-Squares Estimation of the Temperature Variations of a Pasteurization Process

This research shows the control of the pasteurization process in the dairy industry to obtain milk derivatives, which consists of applying heat at a certain temperature, obtaining the elimination of microorganisms, the preservation of nutrients, and product quality, however, when the temperature is exceeded, these benefits are lost. In addition, the PT-100 sensor was used to obtain a quick response and actuate a 2W-0.25-08 solenoid to avoid exceeding 62.8 C°. The development of the project shows the application of a microcontroller that obtained 3 types of samples of 430 data where the instability of the system was observed, so the FIR, ARX, and ARMAX methods were used to see the comparison of these and to be able to choose the most efficient for the process using the MatLab program. It was obtained that the ARMAX method is more effective for temperature control since it allows a fast signal from the sensor to the actuator. In conclusion, applying control with the ARMAX method will prevent the dairy company from exceeding the pasteurization temperature and thus obtain a quality product.