Reliability Of Electric Power System Research Articles

Justification of the structure of the autonomous electric power system of the agro-industrial enterprise

Purpose. Increasing the efficiency of agricultural production and improving the living conditions of the rural population by creating a reliable autonomous power supply system based on its own renewable energy sources. Methods. The substantiation of the structure and parameters of the autonomous electric power system of the economic level was carried out on the basis of the provisions of probability theory, mathematical statistics and simulation modeling using a specially developed reliability assessment model of various variants of autonomous electric power systems for agricultural purposes. Results. The model for assessing the reliability of autonomous electric power systems of the economic level was developed on the basis of the structural and functional organization of systems with the determination of the probability of failure-free operation. The reliability of the system is determined by the reliability of its subsystems and their interconnection – structure. The main method of increasing the reliability of power supply systems is the redundancy method, which consists in introducing additional subsystems into the system. Serial and parallel connection systems are considered. An important element of ensuring high reliability of autonomous power supply systems of agricultural production facilities is appropriate means of energy accumulation. The structure of the specific electricity supply system of the agroindustrial economy should be formed on the basis of the characteristics of production and household needs, assessment of the potential and characteristics of renewable energy sources and the conditions of safe, economically and ecologically efficient operation Conclusions 1. Effective operation of a modern farm with complex automated human activity in close harmony with living objects is possible only under the condition of absolutely reliable power supply, including on the basis of own renewable energy sources. 2. Among the natural RES, the most reliable source for farming conditions is the energy of solar radiation. 3. From the point of view of organization of application, availability of raw materials and possibilities of necessary maintenance, solid biofuel has certain advantages in the conditions of rural areas (the energy cost-output ratio is 1:16). 4. A rational option for a farm can be considered an autonomous power supply system consisting of: a solar power plant, a biofuel power plant, a storage battery – with an estimated reliability index of 0.9997. Keywords: autonomous electric power systems, reliability, solid biofuel, renewable energy sources, power supply, heat supply.

Решение задач электромагнитной совместимости специализированными программными средствами

Reliability and stability of electric power systems depend on compliance with electromagnetic compatibility of electrical equipment, which requires compulsory and objective monitoring. Performing an analysis of power quality in electrical networks is a challenging task, so it is advisable to do it using specialized software. This article gives a brief overview of LabVIEW programming environment and MatLab software package. The possibilities of application of these products for solving the problems of electromagnetic compatibility are considered.

Recloser Placement Optimization In The PDP-03 Radial Network Distribution System Using Ant Colony Optimization (ACO)

The increasing demand for electricity demanded that the power distribution system has a good reliability. To improve the reliability of electric power systems, PT. PLN Area Semarang use Recloser on the electricity network. Nowadays, the determination of recloser position is very important in reliability of electrical power system. Reliability index used in distribution systems are SAIFI and SAIDI. The value of SAIFI and SAIDI can be calculated from the outage time and the failure rate occurred in one year. Reliability can be concluded better if SAIFI and SAIDI smaller. This research aims to determine the optimal placement of recloser location on the electrical network in feeder PDP 03 Pudak Payung substation. The method used for the recloser location placement is Ant Colony Optimization (ACO) using Matlab Software R2014a. From simulation result, it can be concluded that the reliability value before and after placement recloser changed. SAIFI and SAIDI before recloser placement is 1.0172 times/year and 2.5435 hours/year. Optimal placement location for 1 recloser is at a location 4 with a value of SAIFI and SAIDI is 0.3361 times/year and 1.0456 hours/year. While for 2 reclosers is at a location 2 and 7 with a value of SAIFI and SAIDI is 0.26755 times/year and 0.86069 hours/year.

Energy Harvesting Methods for Transmission Lines: A Comprehensive Review

Humanity faces important challenges concerning the optimal use, security, and availability of energy systems, particularly electrical power systems and transmission lines. In this context, data-driven predictive maintenance plans make it possible to increase the safety, stability, reliability, and availability of electrical power systems. In contrast, strategies such as dynamic line rating (DLR) make it possible to optimize the use of power lines. However, these approaches require developing monitoring plans based on acquiring electrical data in real-time using different types of wireless sensors placed in strategic locations. Due to the specific conditions of the transmission lines, e.g., high electric and magnetic fields, this a challenging problem, aggravated by the harsh outdoor environments where power lines are built. Such sensors must also incorporate an energy harvesting (EH) unit that supplies the necessary electronics. Therefore, the EH unit plays a key role, so when designing such electronic systems, care must be taken to select the most suitable EH technology, which is currently evolving rapidly. This work reviews and analyzes the state-of-the-art technology for EH focused on transmission lines, as it is an area with enormous potential for expansion. In addition to recent advances, it also discusses the research needs and challenges that need to be addressed. Despite the importance of this topic, there is still much to investigate, as this area is still in its infancy. Although EH systems for transmission lines are reviewed, many other applications could potentially benefit from introducing wireless sensors with EH capabilities, such as power transformers, distribution switches, or low- and medium-voltage power lines, among others.

A novel methodology for optimal location of reactive compensation through deep neural networks

The present investigation proposes a methodology for the optimal location of reactive compensation in an electrical power system (EPS) through deep neural networks for voltage profile improvement. One of the main parameters to consider regarding EPS reliability is the voltage profile, a parameter that can be affected due to unexpected increases in impedance and loads in the system that translate as overloads in the system and an increase in the number of users. A voltage profile below the minimum or above the maximum accepted in the regulations of each country puts at risk the correct operation of equipment connected to the electrical network and, in turn, can cause economic losses and human lives (e.g by not guaranteeing reliability for hospitals and similar institutions).Economically, one of the most viable alternatives for improving voltage profiles is reactive compensation which in itself is carried out through capacitor banks. Therefore, this work proposes to find the correct location of capacitor banks in an electrical power system (using IEEE 14, 30 and 118 bus-bars systems as cases of study). In each system, the highest reactive load is identified, thus three values for reactive compensation are established as 80%, 50% and 25% of this maximum.Then, with these values, power flows are generated by locating each one of the reactive compensators’ possible values in each one of the bars of the system, hence generating a large number of training data so that finally the neural network is capable of providing a quantitative classification highlighting which compensation and in which bus-bar produces the best result. The result is assessed by applying a modified standard deviation which evaluates the separation of the voltage profiles from the ideal desired value of 1pu.

POWER PLANT MODEL WITH ENVIRONMENTAL CONDITIONS INCLUDED IN THE ELECTRIC POWER SYSTEM RELIABILITY AND AVAILABILITY MODEL

This work presents the results of the theoretical-methodological elaboration of the model by virtue of which the generating units are included in the models for calculation of reliability and availability of the electric power system in the operative plans of its operation. The operation, that is, the operative features of these generating units, and therewith also their reliability and availability, are influenced by the state of the environment, mostly by adverse weather conditions. The generating units model with environmental conditions included also introduces into the calculation of indicators of the electric power system reliability and availability, along with the time dependence, the dependence on the environmental conditions which the unit is exposed to during duration of the period of such conditions.

Reliability methods for delivery of primary energy resources at a power plant during a reliability audit of electric energy systems

Various approaches (nodal, system and estimation) to assessing the reliability of electric power systems, including the effectiveness of fuel supply, are compared and evaluated. A method of statistical testing (Monte Carlo method) is used to assess the reliability of electric power and gas supply systems. For calculating power shortages in electric power systems, the internal points method was used; in order to calculate minimum costs in gas supply systems, the Basaker-Gowan method was used. To calculate the reliability indicators of these systems, probability theory methods were employed, including calculation of probability distribution series, addition and multiplication theorems. Independent tests based on the Bernoulli formula, addition and multiplication theorems, as well as the composition method of distribution series, were used to calculate the distribution series of random states for fuel and electricity supply systems when examining the proposed approaches (nodal, system and estimation approaches). All approaches (nodal, system and estimation) to assessing the reliability of electric power systems, including reliable fuel supply to electric power plants, were evaluated using the following examples: "nodal" and "system" using nominal examples of fuel-supply and electric power systems, as well as "evaluation" using the computational schemes of gas supply and power systems of the North-West Federal District. It is recommended to apply approaches depending on the technological characteristics of the given systems and their connection structure for calculating the base-load provision reliability of energy systems, as well as their feasibility regarding the accuracy of the obtained results, time consumption and the complexity of the data search, preparation and presentation in the model.

A review on distributed generation impacts on electric power system

In 2021, the world's total installed capacity of generation units based on renewable energy sources (not including hydropower) amounted to about 1674 GW: over 825 GW and 849 GW of wind and solar power plants were installed respectively. The growing of the installed capacity of these distributed generators is a response to the increasing the power consumption, global environmental issues and has also become possible due to the development of technology in field of power semiconductor devices. However, on the way of large-scale implementation of distributed generators based on renewable energy sources, traditional electric power system meets new challenges to ensure the reliability and sustainability of new electric power systems with renewable energy sources. In particular, distributed generators change processes in the electric power system, impact to the parameters and power balance, change the magnitude and direction of power flow and short-circuit current, which determines the need to update the settings of the relay protection and automation systems of traditional electric power system and to coordinate their operation with automatic control systems of installed distributed generators. The above-mentioned tasks form a number of scientific research directions, one of which is a task of determining optimal size and location of distributed generators. The main purpose of this optimization task is to reduce power losses, operating and total electricity cost, improve the voltage profile, etc. In addition, the correct and reasonable placement of distributed generators defines an effective planning of the operating modes of electric power system and power plants (especially based on renewable energy sources, the operating modes of which depend on weather conditions and can be sharply variable).The paper highlighted the impacts of distributed generators on power losses, the voltage level, maintaining the power balance and the possibility of participating in the frequency regulation, and short-circuit current in power system. The optimization criteria, the main limiting conditions, as well as methods for solving this optimization problem are considered. This review will help the System operators and investing companies, especially in Russia, to form the main aim, objective function and constraints that will aid to meet their load demand at minimum cost and to choose from the options available for optimization of location and capacity of distributed generators.

Configuration optimization and energy management of hybrid energy system for marine using quantum computing

Improving the technology of hybrid energy systems is an important development direction for the greening of ships, the configuration optimization and energy management of ship hybrid energy system is vital to enhance the marine electric power system reliability, economic efficiency, and sustainability. Focusing on this problem, this paper has carried out a study on the multi-objective configuration optimization method (COM) and energy management strategy (EMS) for ship hybrid energy system based on quantum computing. First, the mathematical model of distributed power modules of the hybrid energy system is established, and a configuration optimization objective function that aims at low-cost, long equipment life, and high reliability of power supply is constructed. Then, the combination with fuzzy rules and quantum multi-objective artificial bee colony algorithm to solve the objective function, the configuration scheme satisfying multiple constraints is obtained. On this basis, an energy management optimization objective function that meets both low-cost operation and maximum clean energy utilization for ship electric power system is established, the objective function is optimized in multi-objective quantum particle swarm optimization (QPSO) algorithm, and the real-time optimal scheduling for hybrid energy systems of the ship is realized. Experiments on simulative navigation data verify the feasibility of the multi-objective configuration optimization method using the quantum artificial bee colony (QABC) algorithm. Furthermore, energy management experiments with different strategies, experimental results show that the energy management strategy proposed in this paper outperforms other methods- and effectively reduces the operating costs, fuel costs, and pollutant emissions of marine power system, meeting the environmental requirements of the Energy Efficiency Operating Index (EEOI) for ships.

Improved load frequency control considering dynamic demand regulated power system integrating renewable sources and hybrid energy storage system

Demand response (DR) has emerged as a key component of the future electric power system's reliability and frequency stability. This study explores the effect of DR regulation and hybrid energy storage (HES) on an identical two-area test power system that comprises of solar photovoltaic, wind turbine, biogas unit, and a thermal power plant for improved frequency regulation services. By including intrinsic communication latency in the DR loop, a generalised load frequency control (LFC) model of a hybrid hierarchical DR mechanism is developed. The stability of the analysed system before and after DR is compared in terms of stability margin. A Quasi- oppositional Harris Hawks Optimization (QOHHO) is suggested to optimize the coefficients of the proposed cascade fractional order two-degree-of-freedom CC[FO(TDOF)] controller. The supremacy of the proposed algorithm is affirmed by comparing its figure of demerit with different existing algorithms. The investigations also manifest the efficacy of proposed controller over proportional integral derivative with filter (PID) and two degree of freedom (tilt integral derivative with filter) [TDOF (TID)] controllers. QOHHO optimized designed controller performance is also evaluated for the studied system under random load disturbances. Furthermore, the suggested technique's practical feasibility is verified through experimental validation using OPAL-RT based real-time analysis.

Reliability Uncertainty Analysis Method for Aircraft Electrical Power System Design Based on Variance Decomposition

As a safety critical system, affected by cognitive uncertainty and flight environment variability, aircraft electrical power system proves highly uncertain in its failure occurrence and consequences. However, there are few studies on how to reduce the uncertainty in the system design stage, which is of great significance for shortening the development cycle and ensuring flight safety during the operation phrase. For this reason, based on the variance decomposition theory, this paper proposes an importance measure index of the influence of component failure rate uncertainty on the uncertainty of power supply reliability (system reliability). Furthermore, an algorithm to calculate the measure index is proposed by combining with the minimum path set and Monte Carlo simulation method. Finally, the proposed method is applied to a typical series-parallel system and an aircraft electrical power system, and a criteria named as “quantity and degree optimization criteria” is drawn from the case study. Results demonstrate that the proposed method indeed realizes the measurement of the contribution degree of component failure rate uncertainty to system reliability uncertainty, and combined with the criteria, proper solutions can be quickly determined to reduce system reliability uncertainty, which can be a theoretical guidance for aircraft electrical power system reliability design.

Improving the energy efficiency of production processes at industrial enterprises of the Russian Federation

The conclusion of the generating equipment for repair, in the optimal way, is the main one when planning repairs. But to consider this issue, it is necessary to understand the essence of the problem and find ways to solve the identified problem. It is necessary to start with the concept of "reliability", namely the reliability of electrical power systems. The article deals with power systems in general, properties of power systems, elements of power systems. The ratio of the functions and properties of energy systems is analyzed, where the main functions of the objects under consideration are: a function associated with the purpose of production equipment, a function associated with the fact of its creation. The meaning of the assignment function is that the object has some task that is performed. In turn, the fulfillment or non-fulfillment of the task is directly related to reliability. Reliability is the property of an object to perform a specified function related to its purpose, subject to specified constraints.

Method for assessing reliability of electric power systems of a structural complex organisation

Method for assessing reliability of electric power systems of a structural complex organisation

Method for assessing reliability of electric power systems of a structural complex organisation

Method for assessing reliability of electric power systems of a structural complex organisation

A method of testing relay protection and automation involving exposure to cascading effects for improved power supply reliability and electric power system stability

The Aim of the paper is to show that improved power supply reliability and electric power system stability are achieved by applying new methods of testing relay protection and automation (RPaA). Major cascading failures in electric power systems are caused by cascading effects, i.e., effects involving several successive effects of various nature. Cascading effects allow extending the functionality while testing RP&A and taking into account the time factor in the context of effects of various nature. Method. A method is proposed for testing relay protection and automation taking into account the cascading effect that is used in the process of development, calibration and installation of protection devices for operation in predefined modes for the purpose of improved power supply reliability and unfailing stability of electric power systems. Result. Intermittent cascading effects do not allow the relay protection and automation recover the electric power system from the post-emergency mode, thus reducing the dynamic stability to the critical level. The diagram of relay protection and automation exposure allows taking into consideration the environmental effects in the process of testing the relay protection and automation. Conclusion. The proposed method of cascading exposure as part of testing relay protection and automation can be used in the process of development, calibration and installation of electric power systems protection and will enable improved stability of electric power systems and reliability of power supply.

Analysis of the Response of a Static Reactive Power Compensator to Instability and Failure in Electrical grids

The reliability of electrical power systems has led to the implementation of new equipment with reliable technology to solve transient failures, in recent decades flexible AC transmission systems (FACTS) have been implemented in power grids, resulting in high levels of stability and control. One of the elements used is static VAR compensators (SVC), however there is very little information about the dynamic response of the device to network instability and electrical failures, for which Simulink analyses the response of the SVC. The device consists of a 47.1 MVar reactive power compensator and a 97.6 MVar inductive reactivator compensator, implemented in a three-phase 500 kV system. The results indicate the effectiveness of response against network instability while maintaining the stable voltage of the network, but against electrical failures the type and time of failure must be considered. In the case of phase-phase faults, the response of the SVC is limited with drops of 0.52 pu.

A Comparative Review of Power Systems Faults Prediction Models

Electrical faults such as in short circuit conditions in power systems result to outages which minimize the reliability of electrical power system due to the equipment failures such as transformers, human error, rotating machines and environmental conditions. These hindering the flow of electricity, damage to equipment and cause death of humans and animals. In view of these, a fault study is routinely performed by utility engineers. However, there were several methods employed by researchers to monitor the states of some important components in power network such as switchgear and transformers, likewise to predict the fault details in all parts of power system. Thus, in this study, different approaches of fault prediction model of power system employed by researchers were reviewed. These approaches have become powerful tools to mitigate the problem of fault occurrence in power system because these tests are carried out more frequently by utilities. This study therefore will help in future planning and smooth operation of the power system and encourage concerned authority to take adequate steps to guide against the predicted faults details in power system. Keywords: Electrical Fault, Reliability, Power System, Short Circuit, Utilities, Equipment Failure DOI: 10.7176/CEIS/12-3-02 Publication date: November 30 th 2021

Dielectric polymer nanocomposites: Past advances and future prospects in electrical insulation perspective

AbstractPolymeric materials enjoy widespread acceptance among electrical insulation design engineers due to their multi‐functional attributes (e.g., excellent dielectric properties, high strength to weight ratio, and ease of molding). However, charge accumulation at the high DC field, poor discharge resistance, low thermal conductivity, limited‐service temperature range, and inadequate stiffness have proven to be severe obstructions to far‐reaching utilization of these materials. To ensure the reliability of today's electrical power systems, novel dielectric materials with enhanced functionalities are essential. An idea that originated under the name of polymer nanocomposites (PNCs) is supposed to provide a viable solution to the challenges mentioned earlier. PNCs are made by mixing a small quantity of nanometer‐sized fillers into a polymer matrix and dispersing them uniformly. To effectively use PNCs in electrical insulation for power apparatus, extensive research into the physical and chemical phenomena associated with these new materials is required. This article aims to provide a comprehensive review of previous research on dielectric PNCs, including synthesis, electrical and nonelectrical characterization, and attendant issues from an electrical insulation standpoint.

Cost of Electricity Outage in Jordan.(Dept.E)

Electric power system reliability is a very important aspect for both producers and consumers. For the former it is important to design an optimally reliable system while for the latter it is important for the economic use of electricity for production and services. Combining the two sides one sets the importance indicator for determining optimum reliability level is the cost of outage to consumers. The authors in this paper present an estimation for the cost of outage using three methodologies. The overall average cost of outage is estimated at JD 0.63/kwh (U.S.S I/kwh) while the specific outage costs are: JD 0.28/kwh, JD 0.32/kwh and JD 1.4/kwh for domestic, industrial and commercial consumers respectively.

Distributed generation as a mechanism to improve the reliability and economic efficiency of electricity systems

The article assesses the application of distributed generation to meet the customer’s own needs for electricity and heat. Currently, the electric power industry is faced with many problems of functioning of electric power systems, which have a negative impact on the processes of transmission and distribution of electric energy to end users. These problems lead to decrease in reliability of power supply and economic efficiency of operation of enterprises. In order to solve the problems of increasing the reliability and economic efficiency of electric power systems the introduction of distributed generation is effective. The modes of electric power generation are considered. The paper also analyzes and identifies the features of the application of distributed generation to achieve the required indicators of reliability and economic efficiency of electric power systems.