Benchmark for PID control of Refrigeration Systems based on Vapour Compression

The Benchmark proposed for the 3rd IFAC Conference on Advances in Proportional-Integral-Derivative Control (PID’18) held in July 2017 is described. This facilitates researchers to test their recent developments in the design of PID controllers on a challenging control problem. The paper focuses on the control of refrigeration systems: the canonical vapour-compression cycle is first described and then the MIMO control problem selected for the Benchmark PID 2018 is addressed, where the cooling power (through the outlet temperature of the evaporator secondary fluid) is intended to be controlled, as well as the degree of superheating at the evaporator outlet, using the compressor speed and the expansion valve opening as manipulated variables. The control systems described in this paper are ready to test other multivariable control strategies, despite being focused on PID regulators. Full documentation about the Benchmark was linked on the website of PID’18 and it will remain in http://www.dia.uned.es/~fmorilla/benchmarkPID2018/.