Abdelazeem A. Abdelsalam

A novel facts compensation scheme for power quality improvement in wind Smart Grid

This paper presents a novel FACTS based Static Switched Filter Compensation (SSFC) scheme. This FACTS SSFC scheme is an effective power quality mitigation, voltage stabilization, power losses reduction and power factor enhancement tool for wind schemes interfaced with Smart Grid-Distribution Networks. The FACTS SSFC-device is controlled by two regulators based on a tri-loop dynamic error driven inter-coupled input to VSC controller. The FACTS filter compensation scheme has been fully validated for effective harmonic mitigation, voltage stabilization, losses reduction and power factor correction using the Matlab Simulink software environment. The proposed FACTS Static Switched Filter Compensator Scheme can be extended to integrate other distributed/dispersed distributed generation schemes for power quality and power factor enhancement and compensation requirements such as voltage stabilization and efficient utilization.

Power quality enhancement in wind-grid interface based on switched filter compensator

Wind energy is an abundant renewable source of energy that can be used to feed isolated electric loads as well as grid connected ones. The variation of wind power with the continuous variations of wind speed can cause significant power quality issues. This paper presents a low cost switched capacitor filter compensator for power quality enhancement and harmonic mitigation of distribution networks with wind energy. The power filter/capacitor compensator scheme provides an effective way to enhance power quality, reduce harmonics.

A novel switched filter compensation scheme for power quality enhancement and loss reduction

The paper presents a novel FACTS-based dynamic voltage regulation and self adjusting switched filter Compensator (SFC). The SFC is controlled by a tri-loop dynamic error driven inter coupled weighted modified PID controller. SFC scheme has been fully validated for effective power quality (PQ) improvement, voltage stabilization, power factor correction and feeder losses reduction. The proposed FACTS based scheme can also be extended to distributed/dispersed renewable energy interface and utilization systems and can be easily modified for other specific stabilization, compensation requirements, voltage regulation and efficient utilization duties enhancement.

Optimal DG Allocation in Radial Distribution Systems with High Penetration of Non-linear Loads

Abstract This paper addresses the optimal distributed generation sizing and siting for voltage profile improvement, power losses, and total harmonic distortion (THD) reduction in a distribution network with high penetration of non-linear loads. The proposed planning methodology takes into consideration the load profile, the frequency spectrum of non-linear loads, and the technical constraints such as voltage limits at different buses (slack and load buses) of the system, feeder capacity, THD limits, and maximum penetration limit of DG units. The optimization process is based on the Genetic Algorithm (GA) method with three scenarios of objective function: system power losses, THD, and multi-objective function-based power losses and THD. This method is executed on the IEEE 31-bus system under sinusoidal and non-sinusoidal (harmonics) operating conditions including load variations within the 24-hr period. The simulation results using Matlab environment show the robustness of this method in optimal sizing and siting of DG, efficiency for improvement of voltage profile, reduction of power losses, and THD. A comparison with particle swarm optimization (PSO) method shows that the proposed method is better than PSO in reducing the power losses and THD in all suggested scenarios.

PSO-based control optimisation of microgrid with D-FACTS

Distributed energy resources are widely used within microgrid to offer optimised electricity supply to meet demand patterns in local regions. A proposed microgrid design comprising novel distribution FACTS devices is presented in this paper. The proposed design is used to stabilise the bus voltages, reduce the feeder losses, improve the power factor and mitigate the harmonic distortion. Modulated power filter compensators and green plug filter compensator are presented as AC-side and DC-side D-FACTS devices, respectively. D-FACTS devices are controlled using multi-loop error driven self-tuned PID controllers. The particle swarm optimisation is developed to optimise the self-tuning of PID controllers to achieve an effective integration of distributed energy resources technologies and to give higher microgrid performance. The results shown are generated from MATLAB simulation of the presented microgrid, where comparisons of the results with and without D-FACTS devices are presented. Results show superiority and improved performance using the presented D-FACTS.

Improvement of power quality in distribution network using a novel DSTATCOM device

This paper proposes a novel custom power device based on distribution static compensator (DSTATCOM) with PID controller driven by the unified error signal (UES) from a multi loop dynamic error controller scheme. Both DSTATCOM and UES are modified to meet the requirements for voltage stabilization, voltage waveform disturbance compensation and power factor improvement. A complete simulation model of the proposed system is developed in Matlab/Simulink Environment. The system is simulated with different control strategies under different operating conditions for comparison. The controllers and the control strategies are developed to have the novel DSTATCOM be operated for voltage stabilization, power factor improvement, energy losses reduction, power quality, and less harmonics distortion. The operational characteristics of a power system, supplying electrical power to hybrid loads consisting of linear and nonlinear and motorized loads, are investigated for better performance and higher power quality employing the proposed DSTATCOM and UES driven controllers.

Optimal distributed energy resources allocation using ant-lion optimizer for power losses reduction

This paper proposes a novel optimization algorithm called ant-lion optimizer (ALO) for optimal distributed energy resources (DERs) allocation in various radial distribution networks. The objective function is to maximize the percentage of power losses reduction. The proposed algorithm is executed on IEEE 34 and 118-bus radial distribution networks with different number of installed DERs. The simulation results using Matlab programming environment show that the effectiveness of the proposed methodology to minimize the losses and to enhance the system voltage profile. A comparison between the results of proposed ALO and those of other optimization methods such as cuckoo search, grid search, oppositional gravitational search, simulated annealing, quasi-oppositional teaching learning based optimization, and chaotic symbiotic organisms search is introduced to verify the superiority of ALO.

Optimal PMUs placement for full observability of electrical power systems using flower pollination algorithm

This paper presents a novel optimization method called flower pollination algorithm to solve the optimal placement problem of phasor measurement units (PMUs) in electrical power systems for achieving full system observability. PMU is considered as a one of the most important measuring devices used for improving state estimation of power system. This problem aims to minimize the number of PMUs to achieve full system observability and maximizing measurement redundancy at system buses. The efficiency and robustness of the proposed optimization method has been tested on the IEEE 14-bus, IEEE 30-bus, IEEE 57-bus, IEEE 118-bus test systems, New England 39-bus and Canal Network 49-bus and Western Delta Network 52-bus at Egypt. The results obtained by the proposed method are compared with other optimization methods such as binary particle swarm optimization method, greedy algorithm, single vertex and binary integer linear programming.

Distribution system performance enhancement using power filter/compensator device

In this paper, a novel low-cost power filter/compensator device is developed and validated for voltage stabilization, power factor correction and harmonic distortions mitigation. The operation of the power filter/compensator device is based on the intermittent switching between a double tuned filter and a series compensator. The switching process is achieved by a pulse signal generated from pulse-width modulation switching. The PID controller which is used to modulate the pulse-width modulation is driven by an error signal generated from a dual loop traditional controller. The Matlab/Simulink software environment is used as a simulation tool. The results show that the power filter/compensator device enhances the power factor and improves the voltage profile at the system buses. Also the power filter/compensator device has a great effect on the mitigation of harmonic distortions of the voltage at the system buses that is downstream it while the enhancement of the harmonic distortions is in the current waveforms at the system buses upstream it.

Dynamic performance of microgrid after fault provoked-islanding considering Induction Motor loads

Microgrids (MGs) are one of the most feasible structures that accommodate the increased penetration of the intermittent renewable distributed energy sources. Enabling MGs with renewable energy sources is crucial to meet the environmental concerns, and get economic benefits and reliability requirements. This paper details the effect of control strategies of an inverter-based distributed generation (DG) on the dynamic performance of MG after fault-caused islanding conditions with the presence of Induction Motor (IM) loads. The dynamic performance of MG is analyzed with different IM load conditions. Further, the effect of DGs penetration levels on the performance of MG is investigated. Voltage and frequency deviations are taken as a key indicator for MG stability. A MG model along with the control strategies is simulated on Matlab/Simulink environment. The model includes a composite generation consists of inverter-based DG and synchronous generator coupled with a critical load which contains static RLC load and IM loads. The simulation results declared that the control techniques of the inverter-based DG are highly affecting the MG stability. Moreover, the MG may lose its stable operation owing to IM loads and DGs penetration levels.