Abstract
The rapid increase in the number of PV installations in current low voltage (LV) distribution networks brings many technical operational challenges. This claims for the deployment of control strategies to deal with these concerns, especially those related to overvoltage issues. Based on this, this paper presents a comprehensive assessment of the performance of PV inverters operating with droop control for overvoltage mitigation using a stochastic methodology based on a Monte Carlo approach. The uncertainty related to the PV generation and the users’ consumption behavior is fully considered through advanced statistical modeling techniques. Voltage magnitude and loading indexes are used as key metrics to assess the technical performance of the distribution network, simulated using OpenDSS, under two droop-based control strategies: Active Power Control (APC) and coordinated Reactive and Active Power Control (RPC-APC). The effects of curtailed energy on the PV users’ revenue is also analyzed. A case of study based on real smart meter data from The Netherlands is used. According to the obtained results, both control strategies are effective to mitigate voltage violations. Nevertheless, for the case of 100% PV penetration, the droop-based coordinated RPC-APC allowed an 18% more of exported energy than the droop-based APC control strategy.
| Original language | English |
|---|---|
| Pages (from-to) | 172-183 |
| Number of pages | 12 |
| Journal | Renewable Energy |
| Volume | 159 |
| DOIs | |
| Publication status | Published - 1 Oct 2020 |
Funding
Part of this research have been partially funded by the projects OPZuid Smart Energy Management (SEM) project (Funded by the European Commission ), the ERA-Net Smart Grid Plus (m2MGRID) project, and the TKI Decentralised Optimisation and Control of Electrical Distribution Grids (DOSE) project. In cases of large PV penetration, above 70%, the operation of both control strategies implemented have a significant impact on the economic operation of the PV owners. In this case, when the PV penetration is 80%, and as it is shown in Fig. 14, the impact of the curtained energy in the annual energy billing is around 371.95% and 105.09%, for Case II and Case III, respectively. Nevertheless, the major impact of the voltage control strategies was observed at PV penetrations higher than 80%. For instance, at 90% of PV penetration, due to the large amount of active power curtailment performed, the SAB varied from −2657.02 € in Case I (this corresponds to the PV owners revenue) to 3613.91 € in Case II. This means that at the end of the year the PV owners will face a fee of 3613.91 €, which corresponds to the value owned to the DSO (or the energy utility). For Case III, this impact is lower as the PV owner will actually receive revenue of −281.39 €, which is 88.7% lower than the one in Case I, i.e., a 88.7% loss of revenue. Notice that for the PV penetration of 100%, in Case III, the SAB is reduced in 37.1% when compared with Case I; while for Case II, the final value is 1143.57 €, which indicates that with such voltage control strategy the PV owners will face a fee for energy consumption at the end of the year. This result clearly shows the impact that this droop-based strategy can have on the PV owners’ revenue. Additionally, it is also important to highlight that, although the SBA reflects the economic impact of the voltage control strategies on the distribution system as a whole, this index does not reflect how each PV owner can be individually affected. Such impact is mainly related to their localization on the feeder, as owners located at the end of the feeder might experience overvoltage issues with higher frequency, leading to higher rates of PV generation curtailment. This suggests that to enable the implementation of such voltage control strategies, a fair approach that distributes among all the PV owners the economic impact derived from the PV generation curtailment is also required.Part of this research have been partially funded by the projects OPZuid Smart Energy Management (SEM) project (Funded by the European Commission), the ERA-Net Smart Grid Plus (m2MGRID) project, and the TKI Decentralised Optimisation and Control of Electrical Distribution Grids (DOSE) project.
Keywords
- Droop control
- LV distribution Systems
- Monte Carlo simulations
- Overvoltage
- PV inverters
