Voltage Stability Analysis in Medium-Voltage Distribution Networks Using a Second-Order Cone Approximation

This paper addresses the voltage stability margin calculation in medium-voltage distribution networks in the context of exact mathematical modeling. This margin calculation is performed with a second-order cone (SOCP) reformulation of the classical nonlinear non-convex optimal power flow problems. The main idea around the SOCP approximation is to guarantee the global optimal solution via convex optimization, considering as the objective function the λ-coefficient associated with the maximum possible increment of the load consumption at all the nodes. Different simulation cases are considered in one test feeder, described as follows: (i) the distribution network without penetration of distributed generation; (ii) the distribution network with penetration of distributed generation; and (iii) the distribution grid with capacitive compensation. Numerical results in the test system demonstrated the effectiveness of the proposed SOCP approximation to determine the λ-coefficient. In addition, the proposed approximation is compared with nonlinear tools available in the literature. All the simulations are carried out in the MATLAB software with the CVX package and the Gurobi solver.

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Security-Constrained Day-Ahead Operational Planning for Flexible Hybrid AC/DC Distribution Networks

Applied Sciences ◽

10.3390/app9214685 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4685 ◽

Cited By ~ 1

Author(s):

Ahmad Asrul Ibrahim ◽

Behzad Kazemtabrizi ◽

Javier Renedo

Keyword(s):

Distributed Generation ◽

Optimal Power Flow ◽

Distribution Network ◽

Distribution Networks ◽

Operational Planning ◽

Hybrid Network ◽

Management Framework ◽

Medium Voltage ◽

Operational Costs ◽

Network Losses

A new active network management framework is presented based on a multi-period optimal power flow problem that is bounded by security constraints at the distribution level for upholding the security of supply. This can be achieved through active engagement with flexible demand and distributed generation to prepare for contingency events in day-ahead operational planning. This framework is coupled with a flexible hybrid AC/DC medium voltage (MV) distribution network topology. It contains an integrated multi-terminal medium voltage DC (MVDC) interface for a seamless interaction and integration of the flexible demand and generation on both AC and DC sides of the hybrid network. The active energy management framework when coupled with a flexible hybrid AC/DC topology provides unprecedented degrees of flexibility as well as security of operation under a variety of conditions. To this end, the 75-bus UK generic distribution network has been modified and converted into a hybrid AC/DC network using the integrated MVDC interface. This framework is then deployed to minimise operational costs to the network operator, considering costs of schemes such as distributed generation curtailment and flexible demand shifting, as well as network losses. Results show a significant improvement in operational costs when the network operates as a flexible hybrid when compared to a pure AC or a more conventional AC/DC hybrid.

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Rancang Bangun Alat Deteksi Stabilitas Tegangan Jangka Panjang Pada Jaringan Distribusi Tegangan Rendah

Electrician ◽

10.23960/elc.v12n2.2078 ◽

2019 ◽

Vol 12 (2) ◽

pp. 33

Author(s):

Osea Zebua ◽

Noer Soedjarwanto ◽

Jemi Anggara

Keyword(s):

Power Distribution ◽

Voltage Stability ◽

Low Voltage ◽

Distribution Network ◽

Distribution Networks ◽

Current Data ◽

Voltage Distribution ◽

Power Distribution Networks ◽

Long Time

Intisari — Stabilitas tegangan telah menjadi perhatian yang penting dalam operasi jaringan distribusi tenaga listrik. Ketidakstabilan tegangan dapat menyebabkan kerusakan pada peralatan-peralatan listrik bila terjadi dalam waktu yang lama. Makalah ini bertujuan untuk merancang dan membuat peralatan deteksi stabilitas tegangan jangka panjang pada jaringan tegangan rendah. Sensor tegangan dan sensor arus digunakan untuk memperoleh data tegangan dan arus. Mikrokontroler Arduino digunakan untuk memproses perhitungan deteksi stabilitas tegangan jangka panjang dari data tegangan yang diperoleh dari sensor. Hasil deteksi kondisi stabilitas tegangan ditampilkan dengan indikator lampu led. Hasil pengujian pada jaringan distribusi tegangan rendah tiga fasa menunjukkan bahwa peralatan dapat mendeteksi gangguan stabilitas tegangan jangka panjang secara online dan dinamis.Kata kunci — Deteksi, stabilitas tegangan jangka panjang, jaringan distribusi tegangan rendah. Abstract — Voltage stability has become important concern in the operation of electric power distribution networks. Voltage instability can cause damage to electrical equipments if it occurs for a long time. This paper aims to design and build long-term voltage stability detection equipment on low-voltage network. Voltage sensors and current sensors are used to obtain voltage and current data. The Arduino microcontroller is used to process calculation of long-term voltage stability detection from data obtained from the sensors. The results of detection of voltage stability conditions are displayed with the LED indicators. Test result on three-phase low-voltage distribution network shows that equipment can detect long–term voltage stability disturbance online and dynamically.Keywords— Detection, long-term voltage stability, low-voltage distribution network.

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Swarm-Intelligence-Based Optimal Placement and Sizing of Distributed Generation in Distribution Network

Advances in Systems Analysis, Software Engineering, and High Performance Computing - Applied Computational Intelligence and Soft Computing in Engineering ◽

10.4018/978-1-5225-3129-6.ch002 ◽

2018 ◽

pp. 29-48 ◽

Cited By ~ 1

Author(s):

Mahesh Kumar ◽

Perumal Nallagownden ◽

Irraivan Elamvazuthi ◽

Pandian Vasant ◽

Luqman Hakim Rahman

Keyword(s):

Distributed Generation ◽

Radial Distribution ◽

Distribution System ◽

Voltage Stability ◽

Reactive Power ◽

Distribution Network ◽

Stability Index ◽

Pso Algorithm ◽

Distribution Networks ◽

Optimal Placement

In the distribution system, distributed generation (DG) are getting more important because of the electricity demands, fossil fuel depletion and environment concerns. The placement and sizing of DGs have greatly impact on the voltage stability and losses in the distribution network. In this chapter, a particle swarm optimization (PSO) algorithm has been proposed for optimal placement and sizing of DG to improve voltage stability index in the radial distribution system. The two i.e. active power and combination of active and reactive power types of DGs are proposed to realize the effect of DG integration. A specific analysis has been applied on IEEE 33 bus system radial distribution networks using MATLAB 2015a software.

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Impact of distributed generation on the operational planning of medium voltage distribution networks using genetic algorithms

IEEE PES Innovative Smart Grid Technologies, Europe ◽

10.1109/isgteurope.2014.7028757 ◽

2014 ◽

Cited By ~ 1

Author(s):

Alexandre A. A. de Souza ◽

Nelson Kagan ◽

Miguel Edgar Morales Udaeta ◽

Klaus de Geus

Keyword(s):

Genetic Algorithms ◽

Distributed Generation ◽

Distribution Networks ◽

Operational Planning ◽

Voltage Distribution ◽

Medium Voltage

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Ultra-high-speed protection for medium voltage distribution networks with distributed generation

2008 IEEE/PES Transmission and Distribution Conference and Exposition: Latin America ◽

10.1109/tdc-la.2008.4641772 ◽

2008 ◽

Cited By ~ 8

Author(s):

M. A. Figueroa ◽

E. Orduna

Keyword(s):

Distributed Generation ◽

High Speed ◽

Distribution Networks ◽

Voltage Distribution ◽

Medium Voltage ◽

Ultra High Speed

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Location and Size of Distributed Generation Using Ant Colony Optimization

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.492.460 ◽

2014 ◽

Vol 492 ◽

pp. 460-466 ◽

Cited By ~ 1

Author(s):

Jorge Mendoza ◽

Miguel López ◽

Allison Delgado

Keyword(s):

Ant Colony Optimization ◽

Distributed Generation ◽

Electricity Generation ◽

Recent Trend ◽

Optimization Technique ◽

Distribution Networks ◽

Ant Colony ◽

Energy Sources ◽

Voltage Distribution ◽

Medium Voltage

Distributed generation (DG) is a recent trend of electricity generation, which aims to use various energy sources to inject electric power in a distributed manner at points close to the load. This paper develops an optimization model to choose the sizes and positions of DG in medium voltage distribution networks in order to minimize the power system losses, given a set of constraints. Ant Colony Optimization (ACO) was used as optimization technique, with excellent results.

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