Electric Power Distribution Systems Research Articles

Communicationless Overcurrent Relays Coordination for Active Distribution Network Considering Fault Repairing Periods

This paper presents an integrated overcurrent relays coordination approach for an Egyptian electric power distribution system. The protection scheme suits all network topologies, including adding distribution generation units (DGs) and creating new paths during fault repair periods. The optimal types, sizes, and locations of DGs are obtained using HOMER software (Homer Pro 3.10.3) and a genetic algorithm (GA). The obtained values align with minimizing energy costs and environmental pollution. The proposed approach maintains dependability and security under all configurations using a single optimum setting for each relay. The calculations consider probable operating conditions, including DGs and fault repair periods. The enhanced coordination procedure partitions the ring into four parts and divides the process into four paths. The worst condition of two cascaded overcurrent relays from the DGs’ presence viewpoint is generalized for future work. Moreover, a novel concept addresses the issue of insensitivity during fault repair periods. The performance is validated through the simulation of an Egyptian primary distribution network.

Analysis of Power Quality and Technical Challenges in Grid-Tied Renewable Energy

The transition of power generation from fossil fuel to renewable energy is a cutting-edge phase in smart grid research. Renewable energy sources (RES), such as solar, photovoltaic, and wind are gradually overtaking other sources as the most attractive alternative within the power generation and distribution systems across many nations. Reduction in the carbon footprint is a major consideration in the choice of the RES. However, the technical challenges with RES pose a significant barrier to unified integration, even though the high penetration level appears plausible. The challenges are majorly caused by the variability and unpredictability of these sources. It is therefore a stimulating task to efficiently manage the electrical power distribution systems in the face of renewable energy integration. The purpose of this study is to examine the potential of renewable energy integration and the accompanying technical challenges that include power quality issues associated with grid-tied renewable energy (GtRE). The study also recommends techniques capable of mitigating prominent power quality challenges to guarantee seamless renewable energy integration in power systems.

Electric power distribution maintenance model for industrial customers: Total productive maintenance (TPM), reliability-centered maintenance (RCM), and four-discipline execution (4DX) approach

The reliability of the electric power distribution system is crucial for industrial consumers, particularly in Karawang Regency, one of the industrial centers in Indonesia. The management of electricity supply for industries in Karawang Regency is entrusted to the Indonesian State Electricity Enterprises, also known as PLN. However, there are still disturbances in the distribution system that affect industrial customers. The primary causes of these disturbances are 39% jointing damage, 36% damage caused by third parties, and 15% damage to cubicles. The occurrence of these disturbances is closely tied to maintenance activities on the electric power distribution system. To assess the distribution system's reliability, various indices are calculated, including the System Average Interruption Frequency Index (SAIFI), System Average Interruption Duration Index (SAIDI), energy not supplied (ENS), and feeder disturbance indices. Currently, PT PLN (Persero) UP3 Karawang employs a maintenance model that combines corrective and preventive methods with the four-discipline execution (4DX) approach. This study aims to develop an improved maintenance model that enhances the overall performance of the electric power distribution system for industrial customers. In this study, a maintenance model is proposed by integrating the total productive maintenance (TPM) method, reliability-centered maintenance (RCM) method, and four-discipline execution (4DX) approach. The developed maintenance model is tested on 40 feeders serving industrial customers. A comparative analysis is performed before and after implementing the maintenance model, considering the SAIFI, SAIDI, ENS, feeder disturbance, and overall equipment effectiveness (OEE) indexes. The analysis of the 40 feeders reveals improvements in performance following the implementation of the maintenance model using the TPM, RCM, and 4DX methods. Prior to implementation, the SAIFI was 0.24 times/cust.yr, SAIDI was 1.877 min/cust.yr, ENS was 60,470 kWh, feeder disturbance occurred 8 times, and OEE was 0.99935. After implementation, the SAIFI improved to 0.016 times/cust.yr, SAIDI reduced to 1.342 min/cust.yr, ENS decreased to 41,241 kWh, feeder disturbance reduced to 4 times, and OEE increased to 0.99962. Consequently, the performance improvements are as follows: SAIFI by 33%, SAIDI by 29%, ENS by 32%, feeder interference by 50%, and OEE by 0.027%.

Use of Plat-Bar Electrode Media to Detect Partial Discharge in Epoxy Resin Materials on PCB Surfaces

The electric power system must have a protection system with reliable electric power isolation, so that the supply of electrical energy works properly and optimally. There are several kinds of disturbances in the electric power distribution system, one of which is a partial discharge. This study aims to investigate the effect of plate-rod electrodes on partial discharge, partial discharge voltage limits in solid insulation, and the characteristics of partial discharge in electrode media, and waveforms in partial discharge detection sensors. After conducting research, it was found that in the plate-rod type electrode media, the PDIV voltage appeared earlier than the plate-plate electrode media due to the cross-sectional area of the electrode media. And the limit of the pre-discharge voltage of PCB type solid insulation on the plate-bar electrodes is at a voltage of 1.3 kV. Several indicators to determine the characteristics of the partial discharge are background noise off (BGN off), background noise on (BGN on), partial discharge inception voltage (PDIV), and partial discharge voltage. After being examined, the value of each partial discharge detection voltage was obtained at negative and positive polarity voltages on the electrode plates and plate needles respectively 2.85 kV, 2.95 kV and 1.32 kV, 1.57 kV.

Impact of Distributed Generation on the Effectiveness of Electric Distribution System Reconfiguration

Distribution system reconfiguration (DSR) is an essential activity in the operation of distribution utilities, usually carried out to lower active power losses and improve reliability metrics. The insertion of distributed generation (DG) units in electric power distribution systems (EPDS) causes the rearrangement of power flows through the conductors and changes the real power losses and voltage profile; therefore, up to a certain point, the insertion of certain quantities of DG may potentially delay or change the reconfiguration strategy of EPDS. This article presents an analysis of the impact of DG, for different locations of the units and different levels of active power supplied by them, on real power losses and on the effectiveness of DSR. The article presents tests with different distribution systems with varying sizes and topologies, showing that the allocation of DG units in buses far from the substation provided the best cost–benefit results. The DSR impact changes depending on the installment location and the generation level of the DG units, corroborating that DSR must be considered and performed using certain criteria, to maximize its efficiency.

SHORT CIRCUIT FAULT ANALYSIS IN THE ELECTRIC POWER DISTRIBUTION SYSTEM AT PT PLN (Persero) UP3 SOUTH MAKASSAR ULP KALEBAJENG USING ETAP

Short circuit fault analysis is needed to determine the amount of short circuit current flowing in a system. This study discusses the single-phase short-circuit current to the ground at the point where the disturbance occurs from the base of the network to the end of the Malewang feeder network. The purpose of this study was to determine the amount of short circuit fault current in the Electric Power Distribution System at PT PLN (Persero) UP3 South Makassar ULP Kalebajeng. This study used the ETAP program and manual calculations. The results of the study found that the contribution of the largest single-phase short-circuit fault current to the ground in the Malewang feeder occurred on Buses located at the base of the network close to the Substation, namely Bus 1 (Exim-Rec Kalaserena) of 0.311 kA, while thesmallest Buscontribution occurred on Buses located at the end of the network far from the Substation, namely Buses 14 (Bilonga) of 0.292 kA. From the results of the study, it can be concluded that the farther the interference bus is from the Substation, the greater the channel impedance. The greater the impedance, the smaller the short-circuit current.

Use of Symmetrical Components in the Study of Electrical Disturbances in Distribution Systems with Charging Allocation for Electric Vehicles and Battery Banks

This paper presents a study of electric power distribution systems, which include battery banks and electric vehicle charging.Emphasis is placed to detect and distinguish voltage disturbances, conductor breaks, and other events that commonly occur in distribution systems. The research uses free license software ATPDraw™ to accurately model distribution systems and replicate voltage characteristics. The study investigates the ideal location of electric vehicle chargers, battery banks and electrical voltage meters in distribution systems. For this purpose, the General Algebraic Modeling System (GAMS) will be used, which provides high-level mathematical optimization capabilities to improve the observability of the system. Research will focus on possible mitigation to the problems these factors can cause in the power distribution system and explore strategies to minimize their negative effects. The discoveries will help improve the system performance, stability, and reliability of power distribution systems and support the integration of electric vehicles and energy storage.

A Symbol Recognition System for Single-Line Diagrams Developed Using a Deep-Learning Approach

In numerous electrical power distribution systems and other engineering contexts, single-line diagrams (SLDs) are frequently used. The importance of digitizing these images is growing. This is primarily because better engineering practices are required in areas such as equipment maintenance, asset management, safety, and others. Processing and analyzing these drawings, however, is a difficult job. With enough annotated training data, deep neural networks perform better in many object detection applications. Based on deep-learning techniques, a dataset can be used to assess the overall quality of a visual system. Unfortunately, there are no such datasets for single-line diagrams available to the general research community. To augment real image datasets, generative adversarial networks (GANs) can be used to create a variety of more realistic training images. The goal of this study was to explain how deep-convolutional-GAN- (DCGAN) and least-squares-GAN- (LSGAN) generated images are evaluated for quality. In order to improve the datasets and confirm the effectiveness of synthetic datasets, our work blended synthetic images with actual images. Additionally, we added synthetic images to the original picture collection to prepare an augmented dataset for symbol detection. In this scenario, we employed You Look Only Once (YOLO) V5, one of the versions of YOLO. The recognition performance was improved, reaching an accuracy of 95% with YOLO V5, after combining the actual images with the synthetic images created by the DCGAN and LSGAN. By incorporating synthetic samples into the dataset, the overall quality of the training data was improved, and the learning process for the model became simpler. Furthermore, the proposed method significantly improved symbol detection in SLDs, according to the findings of the experiments.

Pengaruh Pembebanan Terhadap Efisiensi Transformator Distribusi Di PT. PLN (Persero) UP3 Garut

Transformer efficiency is defined as the ratio of the incoming power to the outgoing electric power. Even so the ideal transformer has 100% efficiency, this ideal transformer does not exist, because the energy that goes out is always less than the energy that goes in, meaning that there is energy loss. Load imbalance in an electric power distribution system always occurs and the imbalance is in single-phase loads in low-voltage network subscribers. Due to the load imbalance, a current appears in the neutral of the transformer. Perform analysis and compare efficiency. Analysis of used load capacity is not efficient. Analysis of the results of current and voltage measurements at the substation to obtain efficiency, and transformer losses in day and night conditions using LWBP and WBP methods. In this study, observations were made regarding the transformer efficiency analysis using the Outside Peak Load Time (LWBP) and Peak Load Time (WBP) methods. The LWBP method is carried out during the day for 20 hours, while the WBP method is carried out at night for 4 hours, from 18.00 to 22.00. Then measurements were made at PT. PLN (Persero) UP3 Garut. For the highest percentage of loading which is close to the standard of 80%, namely the afternoon loading at the PDDK substation, which is 50.93%, the load used is 50.93 kVA. The night load at the CITL substation is 77.49%, the load used is 77.49 kVA. For the lowest percentage of loading that deviates from the standard 80%, namely the daytime loading at the SJRK substation, which is 16.32%, the load used is 16.32 kVA. The night load at the SJRK substation is 21.52%, the load used is 21.52 kVA. Based on observations, it is not efficient because the unused load is very large, it is recommended to use a smaller transformer capacity. The highest efficiency in the LWBP method is at the CITK substation 97.87%, the lowest at the PDDK substation 94.55%. The highest efficiency in the WBP method is at SJRK substations 95.5%, the lowest at PDDK substations is 92.1%.

Analisis Ketidakseimbangan Beban Pada Tranformator Distribusi Di Gardu Induk Budurn

Electricity is a basic need for humans today, it has been proven that humans are very dependent on electricity for their daily activities. If electricity is not available, then human daily activities will be disrupted. The occurrence of load imbalance that occurs in the R, S, and T phases due to the absence of concurrent when the load is turned on, resulting in a neutral current flow on the secondary side of the transformer. with the development of electric power distribution systems. The benefit of reducing losses on the neutral conductor of the distribution transformer is that it can produce savings in the supply of electricity, and other benefits obtained include the resulting system. The method used is that the data resulting from field measurements are converted into mathematical equations. From the research conducted, the results showed the average value of the loading current and load imbalance in the distribution transformer at the Buduran Substation, namely the average loading current of (14.4 A), Load Imbalance of (28.3 A), Neutral Current Losses of (2.34 W). And Copper Losses of (0.510945 kW).

Keandalan Jaringan Distribusi Di Pulau Panjang Dengan Pembangkit Listrik Tenaga Diesel

By examining the issue of the electrical power distribution system's dependability, particularly on the outer islands, in this case Pulau Panjang, it can be seen that the usage of electrical energy in Indonesia is still predominantly controlled by steam power plants. It is discovered that the Diesel Power Plant is this location's primary source of electrical energy. Since 2019, the use of PLTD has been running continuously here, with four primary engines operating efficiently. However, each day, only two machines run alternately for 12 hours, raising a reliability concern that has to be looked into. The SAIDI and SAIFI values obtained using these approaches are extremely high (403,645 for SAIDI and 16 for SAIFI), Then, it was claimed that an index comparison based on SPLN 68-2: 1986, IEEE, and WCS as of January 2022 to June 2022 was erroneous. Thus, the installation of PLTS in the Long Island region is required as a substitute for electrical energy. In order to achieve optimal performance, the diesel working time limit is decreased using the PLTS technology

Coordinated planning of charging swapping stations and active distribution network based on EV spatial‐temporal load forecasting

AbstractElectric vehicles (EVs) charging swapping stations (CSSs), as well as multi‐functional integrated charging and swapping facilities (CSFs), have become important to reduce the impact of e‐mobility on the electric power distribution system. This paper presents a coordinated planning optimization strategy for CSSs/CSFs and active distribution networks (AND) that includes distributed generation. The approach is based on the application of a specifically developed spatial‐temporal load forecasting method of both plug‐in EVs (PEVs) and swapping EVs (SEVs). The approach is formulated as a mathematical programming optimization model that provides the location and sizing of new CSSs, the best active distribution network topology, the required distributed generation, and substation capacities. The developed model is solved using CPLEX, and its characteristics and performances are evaluated through a realistic case study.

Effect of a Single Fault Passage Indicator Placement on Radial Distribution System Reliability under Two Weather Conditions

The components in the overhead electrical network are continuously exposed to the physical environment of varying weather conditions. If the weather around an electrical network is normal and consistent throughout a certain period of time, then the weather can be modelled as normal or single weather (SW). However, in practice, the overhead electrical network is always subjected to varying weather conditions such as normal weather and adverse weather then the weather is modelled as two weather (TW) model. Adverse weather (AW) can cause significant physical damage to the components, resulting in higher average failure rates and longer durations for power restoration. Without considering the weather conditions, the reliability assessment of the overhead electric power distribution system can be over-optimistic, and influence the planning and design decisions. The investigation of system reliability under two weather conditions provides the effect of percentage failures that occurs in severe weather conditions on average interruption duration per customer per year and the amount of energy not supplied per customer per year. This paper evaluates the reliability of a radial distribution system (RDS) considering single weather and two weather conditions. Further, the effect of the fault passage indicator placement on RDS under SW and TW is also evaluated. A fault passage indicator (FPI) is a device that indicates and communicates the fault's location to the operator hence reducing the fault identification time and improving the system reliability by reducing the outage duration time.

Hosting Capacity Assessment in Electrical Power Distribution Systems Using Genetic Algorithm

Environmental issues and the current global energy crisis serve as further motivators for the promotion of renewable energy sources. However, integrating these sources into existing power grids presents numerous challenges. As the connection capacity approaches its limits, it is imperative to employ innovative engineering methods to integrate distributed generation (DG) into resilient, self-healing smart grids of the future. One such tool is Hosting Capacity (HC) analysis, which is an emerging power system-planning tool used to position investments toward parts of the network that can absorb additional generation and promote efficient use of energy sources, avoiding overloading, inefficiencies, DG misallocations, and network failures. In this study, a technique for calculating the ideal HC in a power system is presented. The goal of this research is to develop a replicable optimization methodology for determining HC in smart distribution systems using a single objective constrained optimization problem solved through the use of genetic algorithm (GA). Detailed power system load and generation modeling and the use of advanced open-source research tool for load flow optimization improve the confidence in the proposed model. This research contributes to collective knowledge of the subject matter and establishes a reliable optimization methodology for determining HC in power systems.

Co-Simulation of Electric Power Distribution Systems and Buildings including Ultra-Fast HVAC Models and Optimal DER Control

Smart homes and virtual power plant (VPP) controls are growing fields of research with potential for improved electric power grid operation. A novel testbed for the co-simulation of electric power distribution systems and distributed energy resources (DERs) is employed to evaluate VPP scenarios and propose an optimization procedure. DERs of specific interest include behind-the-meter (BTM) solar photovoltaic (PV) systems as well as heating, ventilation, and air-conditioning (HVAC) systems. The simulation of HVAC systems is enabled by a machine learning procedure that produces ultra-fast models for electric power and indoor temperature of associated buildings that are up to 133 times faster than typical white-box implementations. Hundreds of these models, each with different properties, are randomly populated into a modified IEEE 123-bus test system to represent a typical U.S. community. Advanced VPP controls are developed based on the Consumer Technology Association (CTA) 2045 standard to leverage HVAC systems as generalized energy storage (GES) such that BTM solar PV is better utilized locally and occurrences of distribution system power peaks are reduced, while also maintaining occupant thermal comfort. An optimization is performed to determine the best control settings for targeted peak power and total daily energy increase minimization with example peak load reductions of 25+%.

Dynamic Performance Enhancement of a Triple Active Bridge With Power Decoupling-Based Configurable Model Predictive Control

The multiport active bridge (MAB) converter has been recently proposed aiming to increase the power density and the availability of electrical power distribution systems. However, the dynamic performance of proportional-integral (PI) controller for MAB voltage control is characterized by a relatively slow response and large overshoot. To address this issue, a power decoupling based configurable control (PDC-MPC) strategy inspired by the model predictive control (MPC) was developed. The proposed control strategy can achieve good transient performance and high control flexibility with good precision to comply to DC voltage regulations. In this paper, the PDC-MPC was investigated and implemented in a triple active bridge (TAB) converter with multi-winding high frequency transformers. The operating principle of the PDC-MPC is divided into two phases: prediction of the DC current through a binary search and decoupling of the desired power of each isolated virtual branch to its phase shift angles under the single phase shift (SPS) modulation strategy. Steady-state and dynamic performances of the proposed PDC-MPC for TAB converters were analysed using modified cost function and predictive models. Simulation and experiments were conducted to validate the theoretical analyses.

Real-Time Coordinated Operation of Power and Autonomous Electric Ride-Hailing Systems

Integration of self-driving functions in electric vehicles is radically changing the transportation systems, and representing an opportunity for power utilities to develop innovative solutions for harnessing the spatio-temporal charging flexibility of autonomous electric vehicles (AEVs). This paper develops a multi-agent reinforcement learning model for intelligent real-time coordinated operation of interdependent autonomous electric ride-hailing system (AERS) and power distribution system (PDS), which enables the coordinated routing and charging of AEVs while ensuring the quality of service by meeting spatio-temporal passenger demand and regularly charging the batteries. The proposed model adopts a modified deep Q-network method with multi-agent rollout to determine the near-optimal solution for the coordinated operation problem that determines the routing and charging of numerous AEVs in real-time. The proposed model is tested on a 13-node transportation network, adopted from the Salt Lake City transportation system, and the IEEE 33-bus test power distribution system to showcase the efficiency of the proposed model in determining the real-time routing and charging decisions for AEVs while meeting the operational constraints of both AERS and PDS.

Emulated Inertia Control of Grid-connected Inverter-based Power Supply Sources for Mass Integration of Renewable Energy Resources

This study investigated the important elements of emulated inertia control for grid-connected inverter-based power supply sources and identified the issues to be addressed for its integration into the electric power transmission and distribution system. For the first time, we categorized the emulated inertial control algorithms into five types based on three different aspects. Five emulated inertia control algorithms were simulated in order to compare their effectiveness in suppressing frequency fluctuations. In addition, a representative emulated inertia control algorithm based on the voltage-controlled method and another based on the current-controlled method were distinguished. The two emulated inertia control algorithms were implemented and demonstrated using the experimental hardware of a 5 [kVA] inverter-based power supply.

Inductively coupled distributed static compensator for power quality analysis of distribution networks

<span lang="EN-US">In this research paper, an inductively coupled distributed static compensator (IC-DSTATCOM) for three phase three wire (3P3W) electric power distribution system (EPDS) is proposed. The contraction of power quality (PQ) was marked as a perilous droop mode bump into direct coupled distributed static compensator (DC-DSTATCOM). To regain the PQ, inductive coupling transformer is assisted in conjunction with DC-DSTATCOM. The system equivalent circuit of IC-DSTATCOM is accomplished by take into account of impedance of both transformer and DC-DSTATCOM to reveal the filtering technique. The filtering </span><em><span lang="EN-US">icos</span><span lang="EN-US">∅</span></em><span lang="EN-US"> mechanism is performed by following the generalized mathematical approach using MATLAB/Simulink. A case education is reviewed in detail to illustrate the performance of both DC-DSTATCOM and IC-DSTATCOM. The IC-DSTATCOM is amplified healthier as compared to other in terms of harmonics shortening, good power factor, load balancing, and potential regulation. To examine the effectiveness, simulation outputs of the IC-DSTATCOM with different PQ parameter indices are presented by following the benchmark measure of IEEE-2030-7-2017 and IEC-61000-1 system code.</span>

Neural architecture search algorithm to optimize deep Transformer model for fault detection in electrical power distribution systems

Neural architecture search algorithm to optimize deep Transformer model for fault detection in electrical power distribution systems