Flexible integration of BAS of buildings in service and under construction

With the rapid improvement of intelligent building, some large scale and complex buildings face with several problems. One side is that too many technologies are invented and most of them are incompatible. The other side is that more complex buildings possess a longer life cycle. So to large buildings in its whole life cycle, the longitudinal integration of BAS is an important and difficult issue. When a building which has built a relatively advanced and complete building automation system (BAS) for several years faces with some modification nowadays, we should draw the balance line between advance and compatibility of the newly selected technology and the maximization of investment benefit. How to deal with this problem is the paper´s interested area. A new approach based on flexible integration is proposed. The paper firstly introduces today´s situation of BAS with long life cycle, and then reviews the classical three-layer hierarchy model, including bottom field level, middle automation level and upper management level. The integration method in each layer and heterogeneous integration methods are described in detail. To prove their feasibility, a use case scenario based on an actual engineering application is presented. The results show that the employed flexible integration method can solve the problem, at least a part of the problem.