Voltage and reactive power regulation by photovoltaics in distribution systems

Nowadays, response to electricity consumption growth is mainly supported by efficiency; therefore, this is the new main goal in the development of electric distribution networks, which must fully comply with the system’s constraints. In recent decades, the issue of independent reactive power services, including the optimal placement of capacitors in the grid due to the restructuring of the electricity industry and the creation of a competitive electricity market, has received attention from related companies. In this context, a genetic algorithm is proposed for optimal planning of capacitor banks. A case study derived from a real network, considering the application of suitable daily profiles for loads and generators, to obtain a better representation of the electrical conditions, is discussed in the present paper. The results confirmed that some placement solutions can be obtained with a good compromise between costs and benefits; the adopted benefits are energy losses and power factor infringements, taking into account the network technical limits. The feasibility and effectiveness of the proposed algorithm for optimal placement and sizing of capacitor banks in distribution systems, with the definition of a suitable control pattern, have been proved.

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Multi-objective optimization of optimal capacitor allocation in radial distribution systems

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2019-0206 ◽

2020 ◽

Vol 21 (3) ◽

Author(s):

Sayed Mir Shah Danish ◽

Mikaeel Ahmadi ◽

Atsushi Yona ◽

Tomonobu Senjyu ◽

Narayanan Krishna ◽

...

Keyword(s):

Radial Distribution ◽

Distribution System ◽

Distribution Systems ◽

Reactive Power ◽

Stability Index ◽

Distribution Networks ◽

Optimization Method ◽

Optimal Size ◽

Multi Objective Optimization ◽

Multi Objective

AbstractThe optimal size and location of the compensator in the distribution system play a significant role in minimizing the energy loss and the cost of reactive power compensation. This article introduces an efficient heuristic-based approach to assign static shunt capacitors along radial distribution networks using multi-objective optimization method. A new objective function different from literature is adapted to enhance the overall system voltage stability index, minimize power loss, and to achieve maximum net yearly savings. However, the capacitor sizes are assumed as discrete known variables, which are to be placed on the buses such that it reduces the losses of the distribution system to a minimum. Load sensitive factor (LSF) has been used to predict the most effective buses as the best place for installing compensator devices. IEEE 34-bus and 118-bus test distribution systems are utilized to validate and demonstrate the applicability of the proposed method. The simulation results obtained are compared with previous methods reported in the literature and found to be encouraging.

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Electric Vehicle Charging with Reactive Power Compensation to Distribution Systems

2020 IEEE Industry Applications Society Annual Meeting ◽

10.1109/ias44978.2020.9334838 ◽

2020 ◽

Author(s):

Khalil Sinjari ◽

Joydeep Mitra

Keyword(s):

Electric Vehicle ◽

Distribution Systems ◽

Reactive Power ◽

Reactive Power Compensation ◽

Electric Vehicle Charging ◽

Vehicle Charging

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Full-Observable Three-Phase State Estimation Algorithm Applied to Electric Distribution Grids

Energies ◽

10.3390/en12071327 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1327 ◽

Cited By ~ 7

Author(s):

Thiago Soares ◽

Ubiratan Bezerra ◽

Maria Tostes

Keyword(s):

State Estimation ◽

Real Time ◽

Distribution Systems ◽

Phase State ◽

Reactive Power ◽

Estimation Algorithm ◽

Load Flow ◽

Electrical Network ◽

The Real ◽

Three Phase

This paper proposes the development of a three-phase state estimation algorithm, which ensures complete observability for the electric network and a low investment cost for application in typical electric power distribution systems, which usually exhibit low levels of supervision facilities and measurement redundancy. Using the customers´ energy bills to calculate average demands, a three-phase load flow algorithm is run to generate pseudo-measurements of voltage magnitudes, active and reactive power injections, as well as current injections which are used to ensure the electrical network is full-observable, even with measurements available at only one point, the substation-feeder coupling point. The estimation process begins with a load flow solution for the customers´ average demand and uses an adjustment mechanism to track the real-time operating state to calculate the pseudo-measurements successively. Besides estimating the real-time operation state the proposed methodology also generates nontechnical losses estimation for each operation state. The effectiveness of the state estimation procedure is demonstrated by simulation results obtained for the IEEE 13-bus test network and for a real urban feeder.

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Optimal Capacitors Placement of Distribution Systems Using 2nd Order Power Loss Sensitivity Analysis and Hierarchical Clustering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.986-987.377 ◽

2014 ◽

Vol 986-987 ◽

pp. 377-382 ◽

Cited By ~ 1

Author(s):

Hui Min Gao ◽

Jian Min Zhang ◽

Chen Xi Wu

Keyword(s):

Sensitivity Analysis ◽

Hierarchical Clustering ◽

Distribution System ◽

Power Flow ◽

Distribution Systems ◽

Reactive Power ◽

Digital Simulation ◽

Second Order ◽

First Order ◽

The Impact

Heuristic methods by first order sensitivity analysis are often used to determine location of capacitors of distribution power system. The selected nodes by first order sensitivity analysis often have virtual high by first order sensitivities, which could not obtain the optimal results. This paper presents an effective method to optimally determine the location and capacities of capacitors of distribution systems, based on an innovative approach by the second order sensitivity analysis and hierarchical clustering. The approach determines the location by the second order sensitivity analysis. Comparing with the traditional method, the new method considers the nonlinear factor of power flow equation and the impact of the latter selected compensation nodes on the previously selected compensation location. This method is tested on a 28-bus distribution system. Digital simulation results show that the reactive power optimization plan with the proposed method is more economic while maintaining the same level of effectiveness.

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