# Smart Grid Architecture for Rural Distribution Networks: Application to a Spanish Pilot Network
## 5 Study Case
### IDPRs Contributions in the Electrical Network  
The connected functionalities are the balancing of three-phase currents, the compensation of reactive power in the PN and cancellation of harmonic currents. Thus, as to fulfil this goal, the PN is modelled and simulated (time horizon for simulation, one day) in four different scenarios:  
* Scenario (1) serves as the base case; this scenario is representative of the initial state of the PN, which does not comprise IPDRs neither DGs. This scenario comprises the existing unbalance power flows among the three-phase distribution system. * Scenario (2) represents a transitory situation in which SSs are equipped with IDPRs, but there are no DGs. This scenario considers the initial state of the PN in a short term. The objective here is to evaluate the performance of the IDPRs while solving unbalanced power flows (and reactive components) among the three-phase distribution system due to the existing single phase loads. * Scenario (3) represents a fictitious situation in which the PN is not equipped with IDPRs, but it does comprise DGs. This situation can be representative of an unplanned evolution of DGs in a rural area. Such DGs are considered to be single phase facilities and their integration into the network is not pursuing balanced power flows. * Scenario (4) represents a final situation in which the PN is equipped with IDPRs and comprises DGs. The objective here is to evaluate the performance of the IDPRs while solving unbalanced power flows (and reactive components) among the three-phase distribution system due to single phase DGs and loads. The three-phase system of the PN is modelled in DigSilent PowerFactory software (PF v15.2, DIgSILENT GmbH, Gomaringen, Germany), addressing the characteristics previously presented in Section 2.2. The IDPRs, which are working on connected mode, are modelled as current sources. The loads are also modelled as current sources, aggregating the demand at each SS level. Figures 8 and 9 depict the active and reactive power demand profiles at each SS. These profiles derive from real data (see Figure 10) and are directly applied for the base case scenario (1), and also for scenario (2). Active power demand profiles at each SS for scenarios (3) and (4) are derived from the above profiles adding the effect of DGs (see Figure 11). The DG curves were extracted from the repository [59] and were added on the real consumption profiles. Conversely, reactive power demand profiles for scenarios (3) and (4) are the same as for scenarios (1) and (2), since it is assumed that DGs do not inject reactive power and the LV lines of the PN are basically resistive. Figure 8: Active power demand profile for phases A, B and C at each Secondary Substation (SS) for scenarios (1) and (2). Note that both scenarios share the same active power demand profile, so results can be applied to both scenarios. Figure 9: Reactive power demand profile for phases A, B and C at each SS for all scenarios. Figure 12 presents the performance of the IDPR while balancing the three-phase currents at each SS. Presented results refer to the point of connection of the PN with the external grid. As can be seen, in the case there are no IDPRs installed (scenarios (1) and (3)), the currents in the three-phase distribution system could be unbalanced. The provision of supply to consumers is planned by the distributor system pursuing balanced loading through the three phases of its network. This means that each consumer in the PN could be supplied by different phases. If such demand sharing is properly done, the system is translated into similar loading for each of the three-phases of the system (see scenario (1)). The eventual  
Figure 11: Net active power profile for phases A, B and C at each SS for scenarios (3) and (4). Note that both scenarios share the same net active power profile, so results can be applied to both scenarios. Figure 10: Total apparent power feed by each SS and the Pilot Network (PN) during 10 days.