FDD_Modelica

1. Introduction

• (1) This repo is creating fault models in Modelica language for DXCoils and Airloops.
• (2) The fault models of DXCoils are based on the fault-free models in EnergyPlus.
• (3) Fault-free models for DXCoils are a set of performance curve equations, from the EnergyPlus Engineering Reference (Chapter 15.2.4, 15.2.5, 15.2.6, 15.2.7) .
• (4) The fault models of DXCoils were developed by NREL technical report: ** FDD_Algorithms_PurdueU.pdf ** (in the attachment).
• (5) The fault models of DXCoils are available in Ruby language in OpenStudio Measure: https://github.com/NREL/OpenStudio-fault-models/tree/master/fault_measures_2017.
• (6)The airloop fault models are: OA-temperature-sensor fault, SA-temperature-sensor fault, and OA-damper stuck.

2. Fault Models of DXCoils available in OS-Measure (to be implemented in Modelica):

• (1) condenser fouling
• (2) non-standard charging
• (3) condenser fan degradation
• (4) presence of non-condensable in refrigerant
• (5) liquid-line restriction
• (6) evaporator fouling

3. Fault Models for AirLoops:

• (1) biased OA temperature sensor
• (2) biased SA temperature sensor
• (3) OA-damper stuck

4. Fault Models currently not available, but worth exploring using Modelica:

• (1) compressor valve leakage