Hierarchical stabilization control with upper level multi-agent based controller and lower level local controller

This paper presents a hierarchical stabilization control system with a multi-agent based upper level stabilization controller and a lower level local stabilization controller. Two types of intelligent agents are proposed to realize the proposed upper level stabilization controller: a monitoring agent for gathering required information to stabilize the target power system and a stabilization control agent(supervisor) which performs the actual stabilization control on the selected device. All the required information is distributed through computer networks. The lower level stabilization controller utilizes only local information monitored at the site of the controlled device. Whenever interferences of computer networks happen, the multi-agent based stabilization controller is not able to continue the proper control action to stabilize the target power system. Therefore, under such circumstances the control system is switched to the lower level local stabilization controller to continue the stabilization control. To demonstrate the efficiency of the proposed hierarchical stabilization control scheme, experimental studies have been performed on a 5kVA laboratory system with the energy capacitor system as an energy storage device for the stabilization control.