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Using Emulators to Evaluate the Performance of Building Energy Management Systems.

pdf icon Using Emulators to Evaluate the Performance of Building Energy Management Systems. (478 K)
Kelly, G. E.; May, W. B.; Kao, J. Y.; Park, C.


ASHRAE Transactions, Vol. 100, No. 1, [pages unknown], January 1994.


emulator; algorithms; building/HVAC/plant system; building energy management system; energy management; control system; performance evaluation; simulation; test and rating methodology; occupants


The performance of Building Energy Management System (BEMS) is directly related to the amount of energy consumed in a building and the comfort of the building's occupants. One approach with which to evaluate the performance of a BEMS is through the use of an emulator - a special computer/data acquisition system that is connected to the sensor inputs and command outputs of the BEMS. It replaces the building and its heating, ventilating, and air-conditioning (HVAC) systems and uses a computer program to simulate their response to BEMS commands. The BEMS, through its supervisory and/or direct digital control algorithms, then controls the simulated building/HVAC system as if it were an actual one. At the same time, the emulator evaluates the performance of the BEMS in terms of the energy consumed by the simulated building, the degree of comfort maintained in the simulated space, response time, accuracy, etc. This paper describes using emulators to evaluate a BEMS. Major topics include setting up a BEMS and an emulator, evaluating system/command and DDC software, and methodlogies for testing BEMS application algorithms. Considerations are presented for evaluating the programming capabilities of a BEMS, DDC control loop performance, and rating different aspects of BEMS's performance. A brief discussion of BEMS software is also included.