Electrical Power System Network Research Articles

Multi-Objective Optimal Placement of Distributed Generators by Modified BAT Algorithm

Day by day the need for electrical power is increasing due to the continuous growth and development in the social and economical status of the society. By and large in conventional electrical power system network, power flows from generating stations through transmission and distribution system to the end user. The demand for electrical power at the distribution systems is also increasing continuously. In order to meet the increase in the demand for the electrical power, it is required to increase the existing capacities of the generation and transmission & distribution system that involves lot of money and is a time consuming process. The best solution for this problem of increase in load demand is perfectly met with electric power generating units of smaller capacity which are going to be installed locally in the distribution system and are termed as “Distributed Generators (DGs)”. DGs not only supplies electrical power that meets the increase in load demand but also reduces the losses, improves the voltage profile and reliability of the system. To get maximum of these benefits, DGs are to be installed at its best optimal locations and are to be operated at its optimal generating capacities. In this work an algorithm based on MBAT is proposed to find the optimal locations and sizes of the DG units by considering the minimization of multiple objective functions like minimization of real power loss, cost function and total voltage deviation. The proposed algorithm is tested on IEEE-33 radial distribution systems and results are presented.

Pitch A ngle Control through PI and PID Controller based for Wind Energy Conversion System

The worldwide electrical energy consumption is growing day by day and also increasing the demand of power generation. So in addition into the electrical power system network for power production units a large number of renewable energy units is being combined. A wind energy generation system is the economical of all safe renewable energy sources and the environmentally clean in worldwide. The acceptance of variable speed generation systems the recent evolution of variable frequency drive and power semiconductors technology has been aided. Pitch angle control techniques is best factor to improve the efficiency as well as protection of the wind turbine blade. Therefore, presented in the work a comprehensive model of permanent magnet machines in wind turbine system. Modelling and simulation permanent magnet machines with wind turbine system of PI and PID controller based pitch angle control figuring performance is done by using MATLAB software. The significant result of these controller performance is being compared and also shown with validate approach with the existing survey.

An integrated ISM fuzzy MICMAC approach for modeling and analyzing electrical power system network interdependencies

Despite the attention that the modeling and analyis of infrastructure interdependencies have received over the past two decades, only a small number of methods have been proposed for modeling interdependencies among substations (S/Ss) in electric power system (EPS) networks. For this reason, this paper proposes a novel approach that integrates interpretive structural modeling (ISM) and fuzzy cross-impact matrix multiplication applied to classification (MICMAC). While the ISM provides managers with a holistic visual view of interdependencies among S/Ss, fuzzy MICMAC analysis categorizes the S/Ss in terms of their driving and dependence powers. This categorization offers an advantageous tool for decision makers to distinguish between S/Ss and their mutual associations, which enables them to identify the critical S/Ss. For demonstration, the approach is applied to a model and analyzes the independencies within real EPS S/Ss.

RELEVANCE OF DYNAMIC TARIFICATION APPLICATION FOR MICROGRID GENERATION SYSTEMS

The electric power industry of Ukraine is a technologically sophisticated, territorially ramified system combining power generating stations, the United Electric Power System (UES) and distribution electric networks of the country. The level of development of the electric power complex has a decisive influence on the condition of the economy in the state, on solving the problems of the social sphere and people's living standards. And it is no accident that energy independence is always associated with the national security of the state. The electric power complex of Ukraine was formed as an integral part of the electric power complex of the USSR and therefore does not fully comply with the requirements for the energy complex of an independent state. The structure of generating capacities requires a significant change. The strategic goal of the development of the electric power complex is its fundamental restructuring based on the latest technologies, ensuring maneuverability, energy and economic efficiency, environmental acceptability, external competitiveness and market operating conditions, ensuring a stable, reliable, safe, high-quality supply of electric energy to the country's economic and social sectors. Price regulation in the energy market now takes place in statics, which does not allow assessing the dynamic changes in the tariff price of electricity in local isolated systems. With a sudden change in the power of an isolated energy generating system, a change in the tariff price of electricity occurs, which cannot be taken into account when using static models. For the above example, the question arises of the need to use dynamic charging models, including the presence of transients when the generator operating modes change and their influence on the deviation of the real values of the economic parameters of the system. The dynamic impact of the electrical parameters of the generating system on the economic ones is a determining factor for rejecting the generally accepted hourly billing in Ukraine’s energy networks due to its unprofitability. It is relevant to use a model of flexible dynamic pricing, which will ensure an adequate tariff price for electricity.

Analysis of moth flame optimization optimized cascade proportional‐integral‐proportional‐derivative controller with filter for automatic generation control system incorporating solar thermal power plant

SummaryIn the fast developing electric power system network, ancillary services like automatic generation control (AGC) plays a vital and significant role to ensure good quality of power supply in the system. To distribute good quality of power, a hybrid AGC system along with an efficient and intelligent controller is compelled. So, in this article, a cascaded proportional‐integral (PI)‐proportional‐derivative (PD) controller with filter (PI‐PDF) is proposed as secondary controller for AGC system. A nature inspired optimization algorithm named as moth flame optimization (MFO) algorithm is employed for simultaneous optimization of controller gains. Initially, a two‐area interconnected nonreheat thermal power system is investigated. Analysis revealed that MFO‐tuned PI controller performs better than the different optimization techniques tuned PI controller for the same system and PI‐PDF controller performs better than PI controller does. Then, the study is extended to a three‐area interconnected hybrid system with proper generation rate constraint. Area‐1 consists of solar thermal‐thermal unit; area‐2 consists of thermal‐hydro unit and area‐3 thermal‐gas unit as generating sources. Performance of PI‐PDF controller is compared with classical controllers such as PI, PID, PIDF, and PI‐PD controller without filter. Result analysis divulges that MFO‐tuned PI‐PDF controller performs better than all other controllers considered in this article. Robustness of the PI‐PDF controller is evaluated using parameter variations and random load variation.

Planning Framework for Optimal Resource Utilization Strategy in Microgrid

The incorporation of distributed energy resources and technical innovations has restructured the electrical power system network from conventional grid to microgrid. Consequently, significant impacts on both distribution and utilization of power have been observed triggered by diverse operating condition and enhanced power demand. In planning of microgrid, energy management is a critical issue which is related to efficient utilization of available resources at minimum operating cost. Distributed and intermittent nature of generations in microgrid demands efficient and optimal allocation of existing resources. An allocation technique is necessary to attain optimal utilization of assets and to accomplish decision making for optimal power flow route through shortest path. This paper proposes a multi-objective optimization-based resource allocation technique to efficiently control available generation at any load condition to achieve minimum operating cost while maintaining all system constraints. In proposed framework, line flows are maximized to its load-carrying capability and by controlling power flow through shortest possible path. Proposed methodology suggests proper controller position to sustain desired power flow through the shortest path between each generator and load pair. An interconnected microgrid network topology is considered to demonstrate the proposed methodology.

A Comprehensive Review of Power Flow Controllers in Interconnected Power System Networks

Energy security is one of the most crucial factor in the development of any nation. Interconnections among different power system networks are made to lower the overall price of power generation as well as enhance the reliability and the security of electric power supply. Different types of interconnection technologies are employed, such as AC interconnections, DC interconnections, synchronous interconnections, and asynchronous interconnections. It is necessary to control the power flow between the interconnected electric power networks. The power flow controllers are used to (i) enhance the operational flexibility and controllability of the electric power system networks, (ii) improve the system stability and (iii) accomplish better utilization of existing power transmission systems. These controllers can be built using power electronic devices, electromechanical devices or the hybrid of these devices. In this paper, control techniques for power system networks are discussed. It includes both centralized and decentralized control techniques for power system networks. This paper also presents a comprehensive review of HVDC interconnections, asynchronous AC interconnections, synchronous AC interconnections and different types of power flow controllers used in these interconnections. Moreover, some important and multivariable flexible AC transmission system (FACTS) devices such as UPFC and IPFC are also discussed with their merits and limitations. Finally, a new asynchronous AC link called flexible asynchronous AC link (FASAL) system is also described in detail. At last, a summary of the comparative analysis of power system link and power flow controllers is given based on recent publications. More than 400 research articles and papers on the topic of power transfer control are covered in this review and appended for a quick reference.

Studi Perhitungan Indeks Keandalan Sistem Tenaga Listrik Menggunakan Graphical User Interface Matlab pada PT PLN (Persero) Rayon Kota Pinang

The level of reliability of a distribution system is very important to ensure the continuity of electricity supply to consumers. This research was conducted to calculate the Saidi reliability index and the Saifi 20 kV distribution system in Pinang PLN in 2017 with the help of the Matlab R2008a application. A GUI is one of the Matlab programs that is widely used in describing information and commands, and its users are possible to form and format themselves according to the needs of the system itself. With the help of this software, it is hoped that it will be easier to calculate the system reliability index, namely the calculation of SAIDI and SAIFI, then the results can be made so that the database is more organized. The calculation results obtained will show the highest and lowest SAIDI and SAIFI values ​​that occur in each of the current months, making it easier to evaluate, analyze and improve the reliability of the electrical power system network in the future, especially in PT.

THE MAGNETIC FLUX DENSITY OF VARIOUS GEOMETRIES OF ROGOWSKI COIL FOR OVERVOLTAGE MEASUREMENTS

Overvoltage phenomenon is the common problem that always occurs in the power system and can cause the electrical system network breakdown, and in some cases, it may explode. The frequent overvoltage also can affect and degrade the lifespan of the electrical power system components and network. Thus, the overvoltage sensor is needed to overcome this problem matter. The Rogowski coil (RC) is one of an inductive coil group, and it is suitable for measuring the alternating current (AC) and transient currents or overvoltage. This paper demonstrated the effect of RC magnetic flux density, B with difference cross-section, geometries sizing and the number of turns by using Finite Element Method (FEM). Commonly, there are three types of RC widely used; rectangular, circular and oval. Each of these cross-sections has different characteristics in term of performance. The results have shown that the rectangular cross-section is better than oval and circular cross-section based on the number of magnetic flux density.

An integrated two-layer network model for designing a resilient green-closed loop supply chain of perishable products under disruption

Disruption in the electric power system network can have dramatic effects on supply chain performance in terms of economic and environmental objectives, especially for perishable products. This paper addresses the design of a resilient green-closed loop supply chain network for perishable products under the risk of electric power network disruption. The research has presented an integrated model for the interdependent two-layer network structure as a strategy to mitigate the power disruption risk in order to minimize the expected total network cost and the expected total amount of carbon emissions. Integration of two networks on both objectives along with the effect of products’ lifetime has been analyzed in a real case study of the dairy industry. The results designate that the integration of the two networks leads to improvements in both objective functions. The average total network cost and total carbon emissions have been reduced by 21% and 25% compared to the non-integrated layers, respectively. Furthermore, by increasing the products lifetime, the projected model enjoys higher performance being compared with the non-integrated layers model. This paper concludes that the integrated decision making about the infrastructure networks e.g. power network with the supply chain enjoys economic and environmental benefits for both networks layers under power network disruptions.

Simulasi Daya Harmonik berbasis Transformasi Wavelet dengan Matlab

The progress of power electronics application technology, harmonic pollution in the electrical power system network is increasing seriously, having a serious impact on the energy supply network and equipment. In this discussion, the author studied harmonic characteristics, analysis of harmonic detection methods using wavelet algorithms with Matlab. The results of the simulation show that wavelet transforms can compose harmonic components that are settled in the system according to their needs.

REVIEW OF SCADA SYSTEM FOR DISTRIBUTION POWER SYSTEM AUTOMATION

Power system should be economic, reliable, stable and with high quality operation of the system. The major challenge is to achieve its operation goals with overcome on its continuous problems, therefore power system automation comes into consideration to achieve the best quality operation level of electrical power system network. Automation is defined as the usage of machines thus eliminating human efforts to finish a task. Power system automation is the act of automatically monitoring and controlling the power system via instrumentation and control devices. Power system automation is to incessant monitoring and controlling of all elements and parts in the electrical network, this concept achieves by collecting all required and essential information from field to central monitor and control location. This paper provides an overview of the automation of the distribution power system architecture and its main components.

Enhancing the performance of distance protection relays using interactive control system

Recently improvement of automation systems for electrical power system network became essential for increasing the realiability of power transmission during any disturbance. In a substations the setting of Distance Relays (DRs) are set manually which depends on human experience which may be led to undesirable operation. Any power transmission system may subjected to shortens and loss of adjusting its protection setting, DRs in protection systems are responsible for protected a High voltage transmission lines from short circuit, power swing, and load encroachment, A proposes automation system architecture is introduced to cover the setting and coordination of protection scheme based on DIgSILENT power factory, SIMATIC manger, and WinCC programs.

UNDERSTANDING THE LIGHTNING DISCHARGE WITHSTAND AND BREAKDOWN CHARACTERISTICS OF NANO SiO2 MODIFIED MINERAL OIL FOR TRANSFORMER APPLICATIONS

The successful operation of electrical power system network depends on the performance of insulation provided in the high voltage power transformers. Recent output of many research works confirm that the nano modified insulation system provides enhanced dielectric and thermal characteristics when compared with conventional system. Now a days nano modified mineral oils are considered as an alternative to conventional mineral oils as a dielectric insulation fluid in power transformers, leading to the improved dielectric strength of apparatus with further reduction in the size and manufacturing cost. Since distribution transformers are mainly used in outdoor applications, understanding its lightning discharge withstand and breakdown characteristics of nano modified insulating fluid is a vital issue. In this paper laboratory experimental works are performed to understand the lightning discharge performance of mineral oil along with SiO2 nanofiller at different %wt concentration such as 0.01%, 0.05% and 0.1%. Standard lightning impulse voltage of 1.2/50 µs time period with both positive and negative polarity is used in the experiments. Results illustrate that the nano modified mineral oil significantly improves the lightning impulse withstand and breakdown strength of insulation system.Â

Steady-state analysis of the integrated natural gas and electric power system with bi-directional energy conversion

Nowadays, the electric power system and natural gas network are becoming increasingly coupled and interdependent. A harmonized integration of natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables in terms of system flexibility. This work focuses on the steady-state analysis of the integrated natural gas and electric power system with bi-directional energy conversion. A unified energy flow formulation is developed to describe the nodal balance and branch flow in both systems and it is solved with the Newton–Raphson method. Both the unification of units and the per-unit system are proposed to simplify the system description and to enhance the computation efficiency. The applicability of the proposed method is demonstrated by analyzing an IEEE-9 test system integrated with a 7-node natural gas network. Later, time series of wind power and power load are used to investigate the mitigation effect of the integrated energy system. At last, the effect of wind power and power demand on the output of Power to Gas (P2G) and gas-fired power generation (GPG) has also been investigated.

A planning approach for reducing the impact of natural gas network on electricity markets

In this paper, we present a planning approach for reducing the impact that failure events in the natural gas (NG) network impose on the electricity market operation. For this purpose, an efficient computational methodology based on the Monte Carlo sequential simulation approach is developed, in order to realistically simulate the annual operation of the NG network and deduce the failure events at the connection nodes of the NG-fired power plants. The failure events are then fed into a mid-term scheduling model based on the day-ahead electricity market clearing algorithm, in order to quantify their impact on electricity prices, unit commitment and dispatch, and the energy mix. An appropriate methodology on the location selection of new storage capacity in the NG network is also described, and a case study based on the combined Hellenic electric power system and NG network is used as a test-bed for evaluating the alternative locations.

Performance Analysis of Packet Transport Network Communication for Integrated Wide-Area Protection

As a new protection, wide-area protection enables protective relaying, and automatic control based on electric power system network communications and comprehensive judgment of multi-point information, which plays an increasingly important role in the secure and stable operation of electric power system. Interaction of wide-area information relies on communication network featuring high reliability and low time delay. On the other hand, most service of power transformation station is gradually towards IP and data oriented, along with the development of smart grid. This paper aims to introduce the wide-area protection technology supported by Packet Transport Network (PTN) communication technology, with analyzing the QoS (Quality of Service) network assurance architecture of PTN network, which establishes three planes, including transport plane, management plane, and control plane, based on ASON (Automatically Switched Optical Network) technology. After demonstrating the QoS assurance system of PTN from traffic control and transmission route, this paper introduces PTN networking test. Based on detailed parameters in the test results, the transmission performance of PTN on time delay, protection, and time synchronization of various electric power communication services are analyzed, with showing that PTN can fully meet the requirements of electric power communication.

계절 ARIMA 모형을 이용한 국내 지역별 전력사용량 중장기수요예측

Load forecasting is needed to make supply and demand plan for a stable supply of electricity. It is also necessary for optimal operational plan of the power system planning. In particular, in order to ensure stable power supply, long-term load forecasting is important. And regional load forecasting is important for tightening supply stability. Regional load forecasting is known to be an essential process for the optimal state composition and maintenance of the electric power system network including transmission lines and substations to meet the load required for the area. Therefore, in this paper we propose a forecasting method using SARIMA during the 12 months (long-term/mid-term) load forecasting by 16 regions of the South Korea.

A Review of Considered Factors to Penetrate Renewable Energy Resources in Electrical Power System

<p>As an increasing of load demand, scarcity of fossil fuel and penetration of greenhouse gasses (GHG) effect, utilization of renewable energy resources (RER) such as wind, solar, biomass and tidal are rising drastically. Distributed generation (DG) is a technology giving opportunity to integrate RER into power system network. These integrations are needed optimal long term planning. Those planning, hopefully, can increase reliability of electrical power system network while saving environment from GHG with minimum infestation, operation and maintenance cost. The aim of this paper is reviewing factors should be consider when preparing, operating and evaluating electrical power system with integration of RER. By this planning, it is expected that its integration is effective and efficient in a lifetime of project. Finally, this review can help government, researcher, engineer and private sector to make policies to preparing hybrid power system-DGs. </p><p><strong>Keywords</strong>: <em>Penetration of renewable energy resources, electrical power system, long term planning, distributed generation, policies </em></p>

Analysis of the Robustness and Recovery of Critical Infrastructures by Goal Tree–Success Tree: Dynamic Master Logic Diagram, Within a Multistate System-of-Systems Framework, in the Presence of Epistemic Uncertainty

In this paper, we evaluate the robustness and recovery of connected critical infrastructures (CIs) under a system-of-systems (SoS) framework taking into account: (1) the dependencies among the components of an individual CI and the interdependencies among different CIs; (2) the variability in component performance, by a multistate model; and (3) the epistemic uncertainty in the probabilities of transitions between different components states and in the mean values of the holding-times distributions, by means of intervals. We adopt the goal tree success tree–dynamic master logic diagram (GTST–DMLD) for system modeling and perform the quantitative assessment by Monte Carlo simulation. We illustrate the approach by way of a simplified case study consisting of two interdependent infrastructures (electric power system and gas network) and a supervisory control and data acquisition (SCADA) system connected to the gas network.