28 research outputs found
The method of checking equations for energy resources flows data validating
The development of energy resources flows verifying methods is aimed primarily at automatic energy accounting systems improvement. Creation of the hi-technology energy resources metering and accounting systems supports the practical application of the total energy efficiency concept and enables the financial mutual settlements between the parties to be improved. The paper presents an advanced mathematical method of checking equations (CE) for monitoring the validity of metering data in the energy transportation networks. The analysis of CE mismatches allows all the measurements of any energy resource flows to be divided into four groups: true, false, uncertain and untestable (critical). The method proposed in the paper gives an opportunity to detect bad data and its source. Also, it provides for a bad data filtering at the stage of data acquisition. © 2013, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved
A mathematical method of energy resources flows data validating using the state estimation theory
The energy efficiency improvement is known to start with creating the hi-technology energy resources metering and accounting system which enables the financial mutual settlements between the parties to be improved. With data errors or data loss due to any process failures, the financial consequences may turn out to be severe. As a rule, currently existing methods for energy billing imply a posteriori detection of gross errors in the measurements, which often leads to heated arguments of the parties involved and sometimes results in litigation. The paper presents a mathematical method for monitoring the validity of metering data in the energy transportation networks. The method proposed in the paper gives an opportunity to improve the reliability of measurements of energy, to smoothen inaccurate measurements and slight inconsistencies. Also, it provides for a bad data filtering at the stage of data acquisition. Taking into account developing the production infrastructure and increasing attention being paid to energy efficiency, the methodology is very promising. © 2012, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved
An experience of distant consumers power supply by means of the renewables given specific conditions
Local renewable energy resources (RES) are often considered as an alternative to the conventional power supply by means of power lines. This is an urgent approach for rural electrification if there are long distances from main substations, and distribution feeders’ construction and service is not cost-effective for grid companies. Nevertheless, the real potential for RES implementation at some regions could be limited by economic, geographical and climatic factors especially. The paper gives a review of the experience of power supply type selection for distant consumers given the specific northern continental conditions. The main goal of the paper is the methods estimating technical and economical efficiency of power supply system alternatives including centralized power supply and standalone microgrid implementation to select suitable power supply variant. © 2016, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.Ministry of Education and Science of the Russian Federation, Minobrnauka: 13.1928.2014/KThe work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006 and the Ministry of Education and Science of the Russian Federation (in the framework of state assignment, №13.1928.2014/K (project №1928))
Emergency control algorithm for maintaining power stability based on newton's method
The problem of stability boundary evaluation for the current power system state is of paramount importance for power system operation. In addition, maintaining stability after large scale disturbances has come to the fore in recent years. This paper presents the algorithm, which allows us to both evaluate the stability boundary of a power system and to calculate emergency control actions for maintaining stability in the case of blackout. The algorithm is based on Newton's method for solving optimization problems. There are a number of emergency actions algorithms in literature, but most of them use heuristic rules. On the contrary, the proposed method has a reasonable analytical background. Thus, having an adequate power system model, the proposed method is able to calculate more accurate control actions. The paper demonstrates the very basic idea of the approach with the simplest example. © 2014 WIT Press.International Journal of Safety and Security Engineering;International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen
Demand-side management efficiency estimation in microgrids performed by smart metering systems
The ongoing implementation of the energy accounting tariffs with differentiated rates, which depend upon the market conditions and may change in a short-term perspective, provide the possibility to use it as a financial incentive base of the Demand-Side Management (DSM). On the other hand, modern hi-technology energy metering and accounting systems with a large number of functions and consumer feedback are the good means of DSM. Existing systems of Smart Metering (SM) and consumer feedback are usually not fully used. So, the efforts to combine the market principle, Smart Metering and a consumer feedback are essential. The paper presents multi-purpose system of mathematical statistics and algorithms of DSM efficiency estimation useful for both the consumers and the energy companies. The estimation is performed by SM Data processing systems. The system is focused primarily on a retail market support in Microgrids due to clear and simple framework without the necessity of making large-scale calculations. It contributes to the energy efficiency and a distribution process improvement by the motivation (manual management) or by the Smart Appliances interaction (automated management). © 2014, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved
Estimating distributed generation reliability level
The paper considers the reliability level of different distributed generation units. The world comparative statistics of reliability parameters depending on the unit capacity and other influencing factors are presented. The study includes an analysis of possible approaches to the correction of statistical parameters under the particular conditions. The calculation and analysis of structural reliability parameters for a group of distributed generation units is performed. It is shown that conventional N+1 reliability principle is not enough for distributed generation given a great number of operation conditions. A set of N+n principles is proposed according to the required distributed generation reliability level. Considering the reliability parameters is of great importance for the selection of installed power and the structure of distributed generation for industrial and household facilities under the design and evaluation of its technical and economic efficiency. Gradual growth of the share of distributed generation in power and energy balances of power systems raises the issue of its reliability calculation and regulation. The results obtained in the paper are also important for the maintenance, planning of repairs, and providing necessary logistics solution for the delivery of spare parts and consumables to generating plants. © European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006
Analysing renewable energy flow distribution and its influence on grid electricity prices
The paper presents an approach to the assessment of technical and economic efficiency for an electric energy (EE) transport in a distribution grid. It is focused on the extent of renewable energy sources (RES) integration efficiency according to energy prices in a grid. A two-step procedure for calculation is used in terms of the approach. The first one includes the obtaining of energy flows distribution in a grid. The next step provides the calculation of costs flows and nodal prices for electric energy. Both stages are performed using a developed branch flow model. Unlike power flow distribution describing the instant point of time, energy flow distribution developed for any operation duration deals with the integral values of the flows. This is of great importance for the deeply varying output profiles of the intermittent renewables. The model provides the direct utilization of electric energy meters data available in a grid. The approach presented is essential for locating the particular consumers of the renewable energy in terms of a grid’s deep state and circuit diversity as well as for analyzing the influence of a renewable energy for electricity prices, and estimating the necessary renewables’ levelised cost of energy (LCOE). © 2020, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006
Testing equations method for electrical energy measurements systematic errors detection and measurements results adjustment
Energy flow problem solution based on state estimation approaches and smart meter data
Accurate electric energy (EE) measurements and billing estimations in a power system necessitate the development of an energy flow distribution model. This paper summarizes the results of investigations on a new problem related to the determination of EE flow in a power system over time intervals ranging from minutes to years. The problem is referred to as the energy flow problem (EFP). Generally, the grid state and topology may fluctuate over time. An attempt to use instantaneous (not integral) power values obtained from telemetry to solve classical electrical engineering equations leads to significant modeling errors, particularly with topology changes. A promoted EFP model may be suitable in the presence of such topological and state changes. Herein, EE flows are determined using state estimation approaches based on direct EE measurement data in Watt-hours (Volt-ampere reactive-hours) provided by electricity meters. The EFP solution is essential for a broad set of applications, including meter data validation, zero unbalance EE billing, and nontechnical EE loss check. © 202
Distribution Grid Future Planning under Uncertainty Conditions
The paper presents an approach for making decisions about the future development of a distribution grid under uncertainty conditions. The levels of a grid hosting capacity and adequacy are examined using probabilistic approach compared to the conventional deterministic fit-and-forget approach. It is shown that the probabilistic approach according to the 99 % confidence probability saves significant costs in comparison with the deterministic approach. The probabilistic calculations prove the use of an equipment rated capacity downsized by 2 points of a typical IEC scale, and in some cases to refuse the construction of a parallel circuit. The main contribution of the paper is a method for choosing an effective rated voltage of a distribution grid in a probabilistic interpretation based on the conventional formulas of Still, Zalessky and Illarionov. The technique includes obtaining the probability of loads location at different distances from power supply centre and the probability of load power distribution in a given range of values. It is shown that the calculation using the developed method makes possible to prefer grid rated voltage at least 1 point downsized by IEC scale with sufficient savings due to the difference in the equipment price compared with the deterministic fit-and-forget approach. © 2021, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.Proposed results are the outcome of work on the topic "Development and testing algorithms and technical solutions for digital control of power facilities" within integrated project "Improvement of approaches to digital management of power facilities"