M. Pasamontes

Bumpless switching in control - A comparative study

Industrial processes are characterized by changing dynamics associated to different operating points. Control systems usually face this behavior by adapting the control parameters or switching among controllers, in order to achieve high performance of the system in the whole process operation range. Different methods have been developed to avoid undesirable transients in the closed loop output signal when changes in the control system structure occur. This paper presents a comparative study of some of these methods showing simulation results.

Hybrid Modeling of a Solar Cooling System

Abstract Solar systems are deeply affected by weather conditions and their main energy source, irradiation, cannot be manipulated. This paper describes a solar cooling system located at the University of Almeria, Spain. The system is composed by a solar collector, a gas heather, and two serial connected tanks to storage hot water. They are used as energy sources for an absorption machine whose objective is to obtain chilled water for the fan-coil system. All these components are included or excluded from the cooling system by means of switching valves and activating or deactivating signals. The switching among different configuration modes in real time increases the system challenge to be modeled or controlled, due to the mix of both discrete signals and continuous dynamics. In this paper, a model for each energy source is developed and afterwards they are integrated into one state-space model used to obtain a hybrid model. This hybrid model is able to simulate the different configuration modes of the solar cooling system. Some real tests are presented.

Learning Switching Control: A Tank Level-Control Exercise

A key topic in multicontroller strategies is the mechanism for switching between controllers, depending on the current operating point. The objective of the switching mechanism is to keep the control action coherent. To help students understand the switching strategy involved in multicontroller schema and the relationship between the system dynamics and the switching structure, this paper proposes a student practical where basic linear control knowledge and a simple switching strategy are applied to an educational nonlinear control problem, that of controlling the level in a tank. Evaluation provided by the students is also included.

Easy Mobile Device Programming for Educational Purposes

This paper presents the architecture and several applications of a system aimed at developing mobile device-based courses in an easy and graphical way, without requiring knowledge and programming skills. The proposed system is used to create a remote course about greenhouse climatic control, as well as the necessary steps to build the mobile-based application.