REAL CONTROLLERS IN THE CONTEXT OF FULL-BUILDING, WHOLE-YEAR SIMULATION

Study of complex control strategies plays an increas- ing role in building design. Discrepancy between the intentions of the designer, often expressed as non- formalized control laws, and the as-built implementa- tion is a frequent source of malfunction and energy waste. Two approaches to remedy this problem in the context of equation-based, full-building, whole-year simulation are treated: (1) The availability of Mod- elica based libraries of functional blocks for typical objects such as integrator, gain, PID-controller and time-delay in a general system simulator enables off- line testing and tuning of realistic control systems. (2) Efficient implementation of algorithmic discrete- time controllers enables direct simulation of complex control algorithms described with the same source code in the simulator as in the real controller. The first approach is discussed and illustrated briefly. While not available in traditional building simulation environments, such block libraries have been availa- ble in other simulation domains for several years already. The second approach is treated more tho- roughly, since special methods are needed for build- ings, where controller sampling interval is much smaller than the typical timescales of the equation- based building model itself. Initial implementation and testing of a new simulation approach is pre- sented.