Impact of size and location of distributed generation on overcurrent relays in active distribution networks

Voltage control in active distribution networks must adapt to the unbalanced nature of most of these systems, and this requirement becomes even more apparent at low voltage levels. The use of transformers with on-load tap changers is gaining popularity, and those that allow different tap positions for each of the three phases of the transformer are the most promising. This work tackles the exact approach to the voltage optimization problem of active low-voltage networks when transformers with on-load tap changers are available. A very rigorous approach to the electrical model of all the involved components is used, and common approaches proposed in the literature are avoided. The main aim of the paper is twofold: to demonstrate the importance of being very rigorous in the electrical modeling of all the components to operate in a secure and effective way and to show the greater effectiveness of the decoupled on-load tap changer over the usual on-load tap changer in the voltage regulation problem. A low-voltage benchmark network under different load and distributed generation scenarios is tested with the proposed exact optimal solution to demonstrate its feasibility.

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Research on the Voltage Influence of Active Distribution Network with Distributed Generation Access

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.668-669.749 ◽

2014 ◽

Vol 668-669 ◽

pp. 749-752 ◽

Cited By ~ 3

Author(s):

Xiao Yi Zhou ◽

Ling Yun Wang ◽

Wen Yue Liang ◽

Li Zhou

Keyword(s):

Distributed Generation ◽

Power Distribution ◽

Distribution System ◽

Power Flow ◽

Distribution Network ◽

Distribution Networks ◽

Power Distribution Network ◽

Active Distribution Network ◽

Novel Approach ◽

Active Distribution Networks

Distributed generation (DG) has an important influence on the voltage of active distribution networks. A unidirectional power distribution network will be transformed into a bidirectional, multiple power supply distribution network after DGs access to the distribution network and the direction of power flow is also changed. Considering the traditional forward and backward substitution algorithm can only deal with the equilibrium node and PQ nodes, so the other types of DGs should be transformed into PQ nodes, then its impact on active distribution network can be analyzed via the forward and backward substitution algorithm. In this paper, the characteristics of active distribution networks are analyzed firstly and a novel approach is proposed to convert PI nodes into PQ nodes. Finally, a novel forward and backward substitution algorithm is adopted to calculate the power flow of the active distribution network with DGs. Extensive validation of IEEE 18 and 33 nodes distribution system indicates that this method is feasible. Numerical results show that when DG is accessed to the appropriate location with proper capacity, it has a significant capability to support the voltages level of distribution system.

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Hybrid Harmony Search Algorithm Applied to the Optimal Coordination of Overcurrent Relays in Distribution Networks with Distributed Generation

Applied Sciences ◽

10.3390/app11199207 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9207

Author(s):

Sergio D. Saldarriaga-Zuluaga ◽

Jesús M. López-Lezama ◽

Nicolás Muñoz-Galeano

Keyword(s):

Distributed Generation ◽

Search Algorithm ◽

Short Circuit ◽

Harmony Search ◽

Distribution Networks ◽

Harmony Search Algorithm ◽

Small Scale ◽

Coordination Problem ◽

Overcurrent Relays ◽

Optimal Coordination

In recent years, distributed generation (DG) has become more common in modern distribution networks (DNs). The presence of these small-scale generation units within a DN brings new challenges to protection engineers, since short-circuit currents tend to increase; additionally, as with microgrids, modern DNs may feature several operational modes depending on their topology and the availability of DG. This paper presents a methodology for the optimal coordination of overcurrent relays (OCRs) in modern DNs with a high presence of DG. Given the fact that protection coordination is a non-linear and non-convex optimization problem, a hybrid harmony search and simulated annealing (HS-SA) approach was implemented for its solution and compared against other techniques, such as conventional HS, genetic algorithm (GA), particle swarm optimization (PSO) and hybrid PSO-HS. Several tests were performed on a DN, considering different operative scenarios as a function of the DG available within the network. A comparison with other works reported in the specialized literature was carried out, evidencing the applicability and effectiveness of the HS-SA technique in solving the optimal OCR coordination problem in modern DNs.

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Coordinated allocation of distributed generation, capacitor banks and soft open points in active distribution networks considering dispatching results

Applied Energy ◽

10.1016/j.apenergy.2018.09.095 ◽

2018 ◽

Vol 231 ◽

pp. 1122-1131 ◽

Cited By ~ 12

Author(s):

Lu Zhang ◽

Chen Shen ◽

Ying Chen ◽

Shaowei Huang ◽

Wei Tang

Keyword(s):

Distributed Generation ◽

Distribution Networks ◽

Capacitor Banks ◽

Active Distribution Networks

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Probabilistic determination of the operational flexibility of active distribution networks with high penetration of full-converter interfaced renewable distributed generation units

2015 50th International Universities Power Engineering Conference (UPEC) ◽

10.1109/upec.2015.7339800 ◽

2015 ◽

Cited By ~ 1

Author(s):

Daniel Mayorga Gonzalez ◽

Johanna Myrzik

Keyword(s):

Distributed Generation ◽

Distribution Networks ◽

Operational Flexibility ◽

Renewable Distributed Generation ◽

High Penetration ◽

Active Distribution Networks

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Security-Constrained Optimal Protection Coordination for Dual-Setting Digital Directional Overcurrent Relays in the Distribution Network Including Non-Renewable/Renewable Synchronous Distributed Generation

10.21203/rs.3.rs-238081/v1 ◽

2021 ◽

Author(s):

Sasan Pirouzi ◽

Hosein Hasan Shahi ◽

Mohammad Reza Akbai Zadeh ◽

Amirreza Naderipour ◽

Zulkurnain Abdul-Malek

Keyword(s):

Distributed Generation ◽

Distribution Network ◽

Optimal Solution ◽

Operation Time ◽

Distribution Networks ◽

Time Interval ◽

Dial Setting ◽

Overcurrent Relays ◽

Overcurrent Relay ◽

Optimal Protection

Abstract In this paper, the security-constrained optimal protection coordination (SCOPC) is introduced for dual setting digital directional overcurrent relay (DDOCR) in distribution network, which including renewable and non-renewable synchronous distributed generation (SDG). The SCOPC minimizes the total operation time of DDOCRs in primary and backup protection operating to achieve a fast protection coordination. Also, to improve the flexibility in DDOCRs setting, the allowable limits of A and B coefficients, pickup current (PC) and time dial setting (TDS) in both reverse and forward directions are considered as constraints. Another constraint is the Coordination Time interval (CTI). To consideration of the mentioned scheme security, the SCOPC mechanism considered the unavailability of DDOCRs due to their failure, so the stochastic method is used to modelling of this parameter. To calculate the fault current, network variables are proportional to the daily stochastic operation results of distribution network. Moreover, the proposed problem is implemented on the standard distribution networks, and then the optimal solution is obtained with hybrid algorithm of grey wolf optimization (GWO) and training and learning optimization (TLBO). The numerical results illustrate that the proposed algorithm is able to achieve a reliable and fast protection coordination that has a low standard deviation.

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