Control Structure Selection for Vapor Compression Refrigeration Cycle - Intelligent Computing for Sustainable Energy and Environment - page 484

Fig. 4. The pressure of evaporator
resisting disturbance and strong tracking than the 2I2O controller and 4I4O con-
troller, which indicate that MPC controller based on 3I3O control structure not
only drives the system towards the references satisfactorily but also rejects the dis-
turbancesprovokedbythechangesonthetemperaturevariable,whichisconsistent
with the conclusion obtained by the proposed structure selection criterion.
5Conluon
This paper presents a structure selection criterion to simplify model and select
the optimal control structure for advancing towards further studies. To vali-
date its effectiveness, a comparison study has been carried out. According to
three low-order models, three controllers based on multivariable model predic-
tive control strategy are designed respectively, and the comparative results of
the control performance indicate that the optimal model structure is consistent
with the one obtained by the proposed structure selection criterion. Thus, the
proposed method of choosing optimal control structure for the refrigeration cycle
is a good trade-off which not only decreases the complexity of the computation,
but also improves the reliable control performance.
Acknowledgments. The work was funded by National Research Foundation
of Singapore: NRF2008EWT-CERP002-010. The other project partners are also
acknowledged.
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