HVAC System Modeling and Fault Simulation Research Based on Modelica

HVAC (Heating Ventilating and Air Conditioning) system is a multifunctional air conditioning system that integrates several subsystems such as cooling subsystem and air handling subsystem interacting simultaneously. The causal modeling approach is very complex and difficult to establish an accurate physical model for HVAC system. In addition, the actual HVAC is generally not allowed to operate in a fault state. Therefore, it is difficult to obtain comprehensive and adequate fault sample data directly from the actual HVAC system. In order to solve the shortcomings of causal modeling and the inadequate fault samples of the actual system, an acausal modeling method based on the modelica language is proposed and the faults are simulated in the simulation platform to generate fault samples based on the fault types of the actual system. The results show that this method is not only able to build HVAC system models with more similar topology to the actual physical system but also has better scalability for effective fault simulation of the whole system compared to the traditional causal modeling approach.