Adaptive protection system for distribution networks with distributed energy resources

Modern fault location methods are robust; however, they depend strongly on the availability of the measurements given by Distributed Energy Resources (DER). If the communication or synchronism of this information is lost, the fault location is not possible. This paper proposes an adaptive impedance-based fault location algorithm for active distribution systems. The proposal combines information provided by Intelligent Electronic Devices (IEDs) located at the substation, the knowledge of the network topology and parameters, as well as the distributed power sources, to estimate the fault location. Its adaptive feature is given by the use of a Distributed Energy Resources (DER) electrical model. This model is used to estimate the DER current contribution to the fault, in case the information provided by a local IED is not available. The method takes two types of DER technologies into account: Inverter non-interfaced DER (INIDER) and Inverter-interfaced DER (IIDER). The proposed method is validated on a modified IEEE 34-node test feeder, which was simulated with ATP/EMTP. The results obtained using the IEDs information, presented a maximum error of 0.8%. When this information is not available, the method’s performance decreases slightly, obtaining a maximum error of 1.1%. The proposed method showed better performance when compared with two state of the art methods, indicating potential use for real-life applications.

Download Full-text

Shunt fault analysis methodology for power distribution networks with inverter-based distributed energy resources of the Korea Electric Power Corporation

Renewable and Sustainable Energy Reviews ◽

10.1016/j.rser.2020.110140 ◽

2020 ◽

Vol 133 ◽

pp. 110140

Author(s):

Namhun Cho ◽

Sangwon Yun ◽

Jaesung Jung

Keyword(s):

Electric Power ◽

Power Distribution ◽

Distribution Networks ◽

Fault Analysis ◽

Energy Resources ◽

Distributed Energy Resources ◽

Distributed Energy ◽

Power Distribution Networks ◽

Analysis Methodology

Download Full-text

A Horizon Optimization Control Framework for the Coordinated Operation of Multiple Distributed Energy Resources in Low Voltage Distribution Networks

Energies ◽

10.3390/en12061182 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1182 ◽

Cited By ~ 7

Author(s):

Konstantinos Kotsalos ◽

Ismael Miranda ◽

Nuno Silva ◽

Helder Leite

Keyword(s):

Optimal Power Flow ◽

Low Voltage ◽

Distribution Networks ◽

Heat Pumps ◽

Energy Resources ◽

Distributed Energy Resources ◽

Distribution Grid ◽

Distributed Energy ◽

Control Framework ◽

Optimization Control

In recent years, the installation of residential Distributed Energy Resources (DER) that produce (mainly rooftop photovoltaics usually bundled with battery system) or consume (electric heat pumps, controllable loads, electric vehicles) electric power is continuously increasing in Low Voltage (LV) distribution networks. Several technical challenges may arise through the massive integration of DER, which have to be addressed by the distribution grid operator. However, DER can provide certain degree of flexibility to the operation of distribution grids, which is generally performed with temporal shifting of energy to be consumed or injected. This work advances a horizon optimization control framework which aims to efficiently schedule the LV network’s operation in day-ahead scale coordinating multiple DER. The main objectives of the proposed control is to ensure secure LV grid operation in the sense of admissible voltage bounds and rated loading conditions for the secondary transformer. The proposed methodology leans on a multi-period three-phase Optimal Power Flow (OPF) addressed as a nonlinear optimization problem. The resulting horizon control scheme is validated within an LV distribution network through multiple case scenarios with high microgeneration and electric vehicle integration providing admissible voltage limits and avoiding unnecessary active power curtailments.

Download Full-text