Communication networks for domestic photovoltaic-based microgrid protection

A domestic photovoltaic (PV) based microgrid is a distributed group of small solar PV systems installed at each household in a residential area. The distributed systems may be integrated to form a meshed microgrid structure which can operate in both islanded and grid-connected modes. Grid-connected microgrids of domestic solar PV systems can supplement the energy needs of homeowners. They are a potentially viable option for implementing demand-side management programs for curbing peak demand. Nevertheless, PV-based microgrids, like other microgrid technologies, are notorious for destabilising the National Grid when running in grid-connected mode. They introduce current transient problems, voltage and frequency mismatches, etc. Hence, a solid control and protection scheme is necessary. The backbone of any control and protection scheme is a communication network. Thus, the principal aim of this presentation is to investigate the feasibility of using wireless fidelity (Wi-Fi) for a metropolitan area network (MAN) of intelligent electronic devices (IEDs) used in the meshed network architecture of a microgrid. Supervisory control and data acquisition applications were traditionally based on power-line carrier (PLC) networks. Due to the meshed structure of the proposed network, this approach would dearly complicate the network, as devices such as signal traps and PLC modules would need to be installed on the many buses of the network. Thus, a wireless network, such as Wi-Fi, is a flexible and simpler solution. As an added advantage, Wi-Fi would allow fault location identification through use of triangulation methods. However, issues such as security and the interference proneness of the Wi-Fi protocol need to be considered.