Optimal placement of capacitors in radial distribution system using a Fuzzy-GA method

Requirement of green supply with higher quality has been consumers’ demand around the globe The electrical power system is expected to deliver undistorted sinusoidal rated voltage and current continuously at rated frequency to the consumers This paper presents a comprehensive review of signal processing and intelligent techniques for automatic classification of the power quality (PQ) events and an effect of noise on detection and classification of disturbances It is intended to provide a wide spectrum on the status of detection and classification of PQ disturbances as well as an effect of noise on detection and classification of PQ events to the researchers, designers and engineers working on power quality More than 150 research publications on detection and classification techniques of PQ disturbances have been critically examined, classified and listed for quick reference

A critical review of detection and classification of power quality events

Optimal capacitor placement in radial distribution systems using teaching learning based optimization

Optimal allocation of combined DG and capacitor for real power loss minimization in distribution networks

This paper presents a new genetic algorithm (GA)-based approach for the simultaneous power quality improvement and optimal placement and sizing of fixed capacitor banks in radial distribution networks in the presence of voltage and current harmonics. The objective function includes the cost of power losses, energy losses and that of the capacitor banks. Constraints include voltage limits, number/size and locations of installed capacitors (at each bus and the entire feeder) and the power quality limits of standard IEEE-519. Candidate buses for capacitor placement are selected based on an initial generation of chromosomes. Using a proposed fitness function, a suitable combination of objective and constraints is defined as a criterion to select (among the candidates) the most suitable buses for capacitor placement. A genetic algorithm computes improved generations of chromosomes and candidate buses until the solution is obtained. Simulation results for two IEEE distorted networks are presented and solutions of the genetic algorithm are compared with those of the maximum-sensitivities-selection (MSS), the maximum sensitivities selection-local variations (MSS-LV), and the fuzzy set algorithms. The main contribution of this paper is the computation of the near global solution, with weak dependency on initial conditions.

Optimal placement, replacement and sizing of capacitor Banks in distorted distribution networks by genetic algorithms

This paper presents a new approach to shunt capacitor placement in distribution systems having customers with different load patterns. The allocation of capacitors is considered in a system comprising a network of feeders fed from an upstream equivalent transmission system through a substation transformer. The benefits of capacitor placement, such as the system capacity release and reduction of overall power and energy losses, are considered. The fast method of total energy loss calculation based on the computation of the moments of normalized daily load curves is used to calculate the annual energy loss reduction. An example of optimal capacitor allocation in a distribution system is presented in which customers with commercial, urban residential, rural and light industrial load patterns are considered.

Optimal capacitor allocation in distribution systems using a genetic algorithm and a fast energy loss computation technique

This paper analyzes the temporary overvoltages (TOVs) that may appear in open-phase states in distribution networks with resonant grounding. The high overvoltages recorded during the open-phase states exceed the overvoltages corresponding to the existing theory. The detailed analytical study of the temporary overvoltages is performed. The closed-form expression of the neutral voltage is derived. The conditions for maximum phase-to-earth overvoltages are obtained. The case study for open-phase faults in the 33-kV resonantly grounded distribution network is described. The dependence of the TOVs on the number of distribution feeders, on the feeder loading, on detuning factor, on the additional damping factor, as well as on the saturation of the voltage transformers are analyzed. Remedies for the reduction of TOVs are considered. Detuning of the Petersen coil is compared with the permanent connection of the wattmetric resistance in parallel to the Petersen coil.

Analysis of Temporary Overvoltages During Open-Phase Faults in Distribution Networks With Resonant Grounding

The analysis of current unbalance in power systems with short transmission lines is presented. Measurements in the Israel Electric Transmission System as well as numerical simulations of three-phase load flow have revealed lines with a high level of current unbalance. It is found that significant current unbalance on short transmission lines may take place due to the following reasons: inherent asymmetry of untransposed transmission lines;) presence of line traps used for power-line carriers (PLC); electromagnetic coupling between lines on double-circuit towers; superposition of current symmetrical components in lines under light loading. It is shown that the current asymmetry may lead to overcurrents in individual phases of transmission lines as well as to growth of the magnetic field in proximity of the lines

A. Kalyuzhny

Papers

Optimal capacitor allocation in distribution systems using a genetic algorithm and a fast energy loss computation technique

Analysis of Temporary Overvoltages During Open-Phase Faults in Distribution Networks With Resonant Grounding

Analysis of Current Unbalance In Transmission Systems With Short Lines

System approach to shunt capacitor allocation in radial distribution systems