Survey on microgrids: Analysis of technical limitations to carry out new solutions

Microgrids (MGs) are one of the most promising electrical systems for the next years. Since the definition of the MG paradigm by the first time, the investigation in this area is growing continuously and there are numerous research projects in this moment over the world. This paper makes a survey focused on two important features of MGs: unplanned islanding detection algorithms and inverter control in islanding. Islanding is an inherent property of MGs: the possibility to disconnect them from the main grid in case of disturbance but without stopping the energy generation in the MG. According with this, the different kind of algorithms used to detect the islanding are studied and compared to know their advantages and limitations. Once in islanding, the inverters of the MG must fix new references of voltage and frequency by means of different control techniques. The paper concludes with the solution proposed by the authors: a wireless communication system based on ZigBee in order to exchange the control set point between the inverters.