Coordinated Frequency Control Strategy for an Islanded Microgrid With Demand Side Management Capability

This paper presents a novel coordinated frequency control (CFC) scheme with demand side management capability for an islanded microgrid. The proposed CFC scheme is a communication-free coordination among fast responding devices: thermostatically controlled loads (TCLs), photovoltaic power systems, battery energy storage systems, and a slow responding diesel generator (DZ). The fast responding devices are deployed to achieve a swift frequency regulation in transient state. In steady state, these devices are returned to their normal operating condition by changing loading conditions of the DZ without employing interdevice communication. The proposed control strategy not only achieves frequency regulation in adherence to IEEE Standard 1547, but also maintains customers' quality of service while manipulating TCLs for frequency regulation. A comprehensive study of the proposed CFC scheme is carried out on a modified IEEE 13-bus balanced industrial distribution network using MATLAB/Simulink. In addition, real-time performances of the CFC scheme have been validated experimentally using OPAL-RT simulator, and a well-programmed TMS320F28335 microcontroller. Both the simulation and experimental results demonstrate effective performance of the proposed CFC in achieving efficient frequency regulation.