Effects of superheat nonlinearity on the operational stability of a direct expansion (DX) air conditioning (A/C) system

Yudong Xia, Jing Du, Shiming Deng

Research output: Journal article publicationConference articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

The paper reports a study on examining the influences of superheat nonlinearity on the operational stability of a direct expansion (DX) air conditioning (A/C) system. Using an experimental DX A/C system, the static nonlinearity of the electronic expansion valve (EEV) and superheat nonlinearity of the evaporator exhibited under different operating conditions were obtained. A first-order plus dead time (FOPDT) model was used to characterize the dynamic responses of the evaporator when the experimental system was operated at different compressor speeds and evaporating temperatures. Using Nyquist stability criterion, the effects of superheat nonlinearity on the system operational stability were theoretically analysed. The study results showed that a higher chance to instability would be resulted in when the system was operated at a smaller EEV's opening, a lower compressor speed or evaporating temperature.
Original languageEnglish
Pages (from-to)1854-1859
Number of pages6
JournalEnergy Procedia
Volume142
DOIs
Publication statusPublished - 1 Jan 2017
Event9th International Conference on Applied Energy, ICAE 2017 - Cardiff, United Kingdom
Duration: 21 Aug 201724 Aug 2017

Keywords

  • air conditioning system
  • direct expansion
  • operational stability
  • superheat nonlinearity

ASJC Scopus subject areas

  • Energy(all)

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