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This paper proposes a modified distribution static compensator (DSTATCOM) with the voltage controller. The modified DSTATCOM is incorporated in a three-phase four-wire distribution network. The design criteria of the modified DSTATCOM parameters is introduced. The Hysteresis Voltage Controller (HVC) is used to drive the Voltage Source Converter (VSC) and its reference voltage signal is generated based on the Instantaneous Symmetrical Components Theory (ISCT) to provide the proper compensation to stabilise the system voltage, improve the power factor and mitigate the harmonic distortion. Matlab/Simulink software is used to verify the performance of the modified DSTATCOM with the used controller under different load types and supply voltage conditions. The control algorithm ensures that the bus voltage is maintained at its rated value during different connected loads and supply conditions. Also, it compensates the non-linear and unbalanced supply currents and reducing the Total Harmonic Distortion (THD) of both current and voltage. The proposed modified DSTATCOM gives better results in comparison with the conventional DSTATCOM. [ABSTRACT FROM AUTHOR]

Technical and economic benefits of installing distributed energy resources (DERs) and capacitor banks (C-Bs) can be maximized by optimal allocation of them. The aim of this paper is to enrich technical benefits such as voltage profile, system losses and reliability and also to increase economic benefits by maximizing the savings of energy losses and decreasing the cost of energy not supplied. The work in this paper is divided into three stages; (i) optimal placement of DERs, (ii) optimal placement of C-Bs and (iii) optimal placement of C-Bs with the existence of installed optimal DERs. The daily load variations have been considered to optimally schedule fixed and switched C-Bs. Aim of this work is formulated as a maximum objective function and is solved by a modern optimization algorithm called sine cosine algorithm (SCA). The proposed SCA method is tested on standard IEEE 33 and 69-bus radial distribution systems. Results show that the developed SCA is able to maximize the annual savings and hybrid integration of DGs and C-Bs to distribution networks is preferable than integrating one of them alone. Also, superiority of the proposed algorithm is verified by comparing its results with other optimization methods and by using a non-parametric Wilcoxon statistical test. [ABSTRACT FROM AUTHOR]

This article introduces a problem solution of optimal allocation and hourly scheduling of capacitor banks (C-Bs) using the sine cosine optimization algorithm (SCA) to maximize the cost saving and enhance the system reliability. The impact of reliability enhancement reveals in the objective function as a reduction of energy not supplied cost. The optimal location and size of C-Bs are determined based on two strategies; strategy 1, loss sensitivity factor is used to select the candidate buses after that optimal size of C-Bs is determined by SCA while in strategy 2, the optimal location and size of C-Bs are determined by SCA. The proposed algorithm is tested on IEEE 33 and 69-bus radial distribution systems with different scenarios of single and multi-C-Bs installation. Also the daily load variations have been considered to optimally schedule switched C-Bs steps. The simulation results using Matlab programing environment have been verified using the non-parametric Wilcoxon signed rank statistical test. The superiority of proposed algorithm is also ensured by comparing its results with other optimization methods. [ABSTRACT FROM AUTHOR]

Microgrid (MG) gains higher potential and plays a key role in grid infrastructure upgrade. Although MG have many benefits, its performance during fault caused islanding conditions still needs more attentive investigations. In this context, the MG load types and the behavior of the distributed generations (DGs) control system have the significant impact on the stability of MG. This article analyzes the influence of various control techniques of the inverter DG unit on the dynamic performance MG after fault-provoked islanding conditions. To enhance the MG stability and the quality of voltage waveform, an adapted MG configuration equipped with a low-cost switched modulated power filter compensator (MPFC) is proposed. Using MPFC alongside the inverter DG unit gives adequate solution to overcome the shortcomings of the inverter and the flexibility of the interfacing control scheme. The MG structure equipped with MPFC is simulated using Matlab/Simulink software package. A wide perspective on the simulation results indicates that the MG stability is highly vulnerable to the inverter DG control techniques. Further, the MG may lose its stable operation due to some load type characteristics. The proposed MG structure with the MPFC can withstand longer fault durations and give better stability performance especially with induction motor (IM) loads. Moreover, the MG equipped with the MPFC has the ability to keep the voltage total harmonic distortion (THD) within the acceptable limits. [ABSTRACT FROM AUTHOR]