# Smart Grid Architecture for Rural Distribution Networks: Application to a Spanish Pilot Network
## 3 Electrical Actuations to Evolve the Rural Grid  
As presented in Section 2, traditional rural networks present several weaknesses that difficult their management and planning. Among the aspects mostly affecting the planning, we highlight: the orography and the presence of aged and long resistive distribution lines to access to remote areas with spread and few consumers. In turn, among those affecting the operation, we identify: meteorological conditions that provoke frequent grid faults; sensible over and under voltages that affect power quality for consumers; and the stringent flexibility due to the inclusion of few and manually operated switches and disconnectors.  
Figure 1: Area from Pilot Network (PN) and its electrical scheme.  
Traditionally, electrical utilities solved these issues reinforcing the infrastructure (e.g., commissioning new lines, secondary substations, etc.) This strategy is neither the most economical one, nor possible from regulations for all cases.  
An example addressing economic aspects could be the commitment for distribution operators to feed a consumer in a remote location. In this case, the operator could opt for tracing a new line (and even a dedicated transformer) to the consumer, this being an expensive alternative. As a figure of merit, current prices for low voltage distribution four-wire cables (wire section between 50 mm\({}^{2}\) and 100 mm\({}^{2}\)) are between 10,000 \(\in\) /km and 20,000 \(\in\) /km [38]. Thus, depending on the distance to reach the isolated consumer, the commissioning of the whole new infrastructure could easily reach hundreds of thousands of euros. Instead of doing this, an alternative could be to install smart power electronics with embedded storage at the consumer's place and this may be an economical option, according to the experience of the authors of the present paper.  
Furthermore, as an example of addressing regulatory issues, to increase reliability of a radial network, it may be an option to close it, thus performing a ring with two feeders. However, and because of the orography and limited access to protected natural areas (regulatory issues), it may not be possible. Thus, an alternative is to reinforce such radial network with smart grid technologies (e.g., distributed storage and telecommunications).  
The above examples suggest the development of actuations to update rural grids in a different manner than traditional options, and these are proposed in the present paper. After deploying the innovative grid architecture and addressing the adoption of both new management tools and technologies, the PN will become deeply transformed, resulting in the scheme depicted in Figure 2. Next, the above actions for upgrading the rural grid are listed [18; 26; 32; 39], and the following subsections go deeper into describing the above updates for developing the rural grid: promoting the distributed generation (detailed in Section 3.1); including new protection devices (detailed in Section 3.2); installing back-up resources (detailed in Section 3.3); deploying a proper telecommunications network (detailed in Section 3.4); developing new control and management agents (detailed in Section 3.5); and (detailed in Section 3.6).