Hierarchical structure is a common feature of control solutions of complex dynamic systems. In large discrete-event system (DES) hierarchical supervisory control, provides the higher levels controllers (manager) with simplified abstract models of the lower levels. Generation of electricity and associated loads can be considered as a subsystem or a “microgrid’ in large electrical power systems. This view to microgrid, suggests a hierarchical structure for its supervisory control and operation. During disturbances, the generation and corresponding loads can be separated from the distribution network, to isolate the microgrid from the disturbance (and thereby maintaining service) without harming the transmission grid’s integrity. The difficult task is to achieve this functionality without extensive custom engineering and still have high system reliability and generation placement flexibility. This paper discusses a hierarchical structure for supervisory control of a typical microgrid energy system. The processes and control tasks in each level is determined. We investigate the nature of information and command signals in implementation of the hierarchical supervisory control for a microgrid system. To design a supervisory control in each level, the plant and control specifications should be recognized and models as DESs.
A. Afzalian- and A. Nabavi Niaki
Dept. of Control Systems Engineering, Shahid Abbaspour University of Technology, Tehran, Iran
Dept. of Electrical Engineering, University of Mazandaran, Babol, Iran