Refrigeration loop dynamic analysis using PROTISS

Abstract

Integrated steady state and dynamic simulators represent the next step in the development of process modeling and simulation. PROTISS™ is one such simulator developed by Simulation Sciences. This general purpose process simulation package provides users with an analysis tool through the design phases of a project as well as allowing users to design and test viable control and optimization systems. Operability issues involving optimal process design for the entire range of process operation can be addressed effectively. Furthermore, control and instrumentation issues such as variable pairing, observability, and model mismatch can be addressed earlier in the project. This paper describes the use of the dynamic simulation tool for the operational analysis of a multi-stage refrigeration loop. Particular attention is given to analysis of advanced control system check out and tuning. Studies discussing model validation and tuning are presented for varying cooling load and demand changes and compressor upsets. The ability of the dynamic simulator to solve complex process configurations in real time using high fidelity models is described. The user is able to describe the process configuration in engineering terms. Discussion is provided to highlight the program's ability to solve complex and advanced control configurations. Simulation studies show the utility of using dynamic simulation for the analysis of control strategies with respect to the units performance and robustness issues during events such as load changes and disturbances.