Scientific advisor: doctor of technical science, assistant professor Ivan P. Zabolotny

     Actuality of work  Maintenance of reliability of electrosupply systems work in conditions of structural reorganization of power and introduction of the power market; complications of electropower objects at presence of powerful electroreceivers with sharply variable and nonlinear loading are caused with necessity of efficiency increase of used control systems. Achievements in information technologies, power converting technical equipment, microprocessor technical equipment provide creation of devices and the control systems corresponding to features of decided tasks. However the methodology of construction existing control systems is based by electropower objects on out-of-date information technologies and on rigid mathematical models which do not provide the effective decision of set of versatile technological management tasks. Development of elements condition recognition methods of electropower object and modes of its work, formation of managing influences, the mathematical models adequately reflecting elements in various operating modes is an actual scientific task.

      There are problems of reliable work maintenance for electrosupply systems of the industrial enterprises incorporating consumers with significant sharply variable loading, especially when on the one hand by virtue of various objective restrictions it is not possible to use existing recommendations under the account of separate factors for the decision of electromagnetic compatibility questions, and on the other hand takes place use of various devices of regulation, some of which can promote strengthening of fluctuations.

      As a result of development electrosupply system variants take place when consumers with sharply variable and nonlinear loading work not only on one trunks with consumers with constant loading, but connection of nonconventional the same to trunks of voltage 35 kV and 6-10 kV takes place.

      Besides in electrosupply system on different voltage compensating devices as batteries of condensers with switching devices of relay type and static thyristor equalisers are used; reactors with undernagnetic; synchronous generators with devices of excitation regulation; synchronous and asynchronous engines. In such conditions effective exception of the fluctuations caused by technological processes is an actual task.

      In overwhelming amount the software for the analysis of stationary modes is based on representation of loadings by constants and does not realize the account of features of influence on changes of regime parameters of such elements, as machine of an alternating current, the battery of condensers, static equalisers and devices FACTS used recently.

      To problems which are necessary for taking into account concern:

          - physical deterioration of the equipment working at manufacturing of a resource on the average on 70 % at limited investments on modernization;

          - presence separate automated systems: the account of the electric power, dispatching management; diagnosings , exactly monitoring of separate kinds of the equipment and even separate units at use of various approaches;

          - use of out-of-date information technologies and the technologies of programming sold from a position of the researcher - engineer, instead of the technologist. While the technological task of management today is set of tasks decided earlier separately and concerned to directions: imitating modelling, information support of decisions of the personnel, connected to processing significant volumes of the help, normative and directive information; systems of an artificial intellect;

          - presence of means, modern information technologies at practical absence of toolkit of software for the decision of technological tasks in view of modern requirements from positions of the engineer - technologist.

     An indispensable element of system automatics is presence of starting body which robot defines efficiency of action of automatics in emergency operations. Techniques of construction, option, the analysis of work of starting bodies of system automatics are based on experimental researches and results of mathematical modelling. Thus the most part of researches is carried out by mathematical modelling various modes, and experimental researches are used at the final stage for an estimation of reliability of researches and efficiency work of automatics.

     The purpose of work is generalization and development of mathematical model and research of influence of various factors on stationary modes of electrosupply system of the industrial enterprise, incorporating consumers of electric energy with sharply variable and nonlinear loadings on which substations are established three windings transformers, there are synchronous generators, static thyristor equalisers and batteries of condensers, synchronous and asynchronous engines, current limited rectors and other devices.

     For achievement of the purpose in work the following tasks are put:

          - on the basis of the analysis experimental data to estimate parameters for the account of the indignations caused by features of technological process in consumers with sharply variable loading;

          - to generalize and improve mathematical models of separate elements of system of electrosupply and a stationary mode of system of electrosupply in conditions of changing loadings;

          -to receive mathematical model of generalized device FACTS;

          -by results of modelling to estimate influence of various factors on stationary modes of electrosupply system.

     Object of research are systems of electrosupply of the industrial enterprises with nonlinear and sharply variable loadings; stationary modes of electrosupply systems of the industrial enterprises.

     Novelty of the received results consists of:

          1. The mathematical model of device FACTS distinguished from devices known for the generalized description of various type from the elementary devices of cross-section indemnification of jet capacity up to devices of stabilization of capacity is received.

          2. The mathematical model of the established mode is generalized, distinguished from known themes is advanced, that static characteristics of capacity of alternating current machines take into account saturation on the way of the main magnetic stream, and sharply variable loading is submitted with two components.

      Practical value of work consists of development of the software allowing to execute the estimation of influence on electrosupply system stationary modes sharply variable loadings having various parameters and connected to trunks of average and lowest voltage, devices of regulation of the voltage, having various parameters fluctuations, a design of the power transformer (three winding transformers of identical capacity with a various arrangement of windings on the magnetic circuit, that results in various combinations of voltage of short circuit of pairs windings).