Real Time HEVAC Simulation

Completed (1991 - 1995)


In the near future, the most promising energy saving measures are in advanced control and operational technologies. Lowest energy consumptions, one of the basic factors for reducing managing costs, will be reached together with well-organised maintenance, fast detection and correction of defects and best use of equipment performances. Thus the reliability, availability and the efficient use of the HVAC and control systems will be emphasised in the use and maintenance of buildings.

Partly these characteristics can be affected by integrated planning and product development. Another and parallel way is to develop methods for the real time analysis of the performance of HVAC processes and for the fault detection and diagnosis. The main goal of the Annex was to develop methodological procedures within a defined concept for real time and automatic performance optimisation, diagnosis and fault detection of HVAC processes. The ultimate goal of the project was BOFD prototypes that are implementable in Building Energy Management Systems. Part objectives of the Annex were:

  • To evaluate the best (most suitable) modelling approaches for the real time simulation of HVAC systems.
  • To develop methods for the qualitative availability analysis of HVAC systems.
  • To collect a data base of the most important troubles and faults in HVAC systems.
  • To demonstrate the implementation of the concepts in conjunction of a real BEM system.

The Annex concentrated on the energy performance diagnosis of a building and HVAC systems and the fault detection of HVAC components and subprocesses.

Main achievements:

  • A general BOFD system concept paper.
  • A classification of BOFD methods (draft report).
  • Reference systems; list of typical faults; and ranking of faults.
  • First applications of selected BOFD methods.
  • Test rigs.
  • New component and fault models.
  • Prototype expert system cell.

Operating Agent

Prof Reijo Kohonen
ABB Installaatiot Oy
Takomotie 8 A
Postfach 181
FIN-00381 Helsinki
Tel: +358 0564 8196


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