The purpose of the paper is to investigate dependence of input current harmonic spectrum of modern frequency converters with uncontrolled rectifiers on supply network power , rated power and motor load, and also the DC filter capacity. Results of the investigations are given in the form of the corresponding dependencies and an estimation of correspondence of higher current harmonic levels generated by a frequency converter to the existing state standard.

The paper contains formulae of the simplified calculation of maximum conductor tension at stages of their movement during short circuit. Assurance estimation of the simplified calculation is done on the basis of the experimental data and calculative experiment. Correction factors for higher accuracy of the simplified calculation are proposed in the paper.

An experience in teaching linear electrical circuit theory at the Azerbaijan Technical University is presented in the paper. The paper describes structure of the Linear Electrical Circuit Theory course worked out by the authors that contains a section on electrical calculation of track circuits, information on electro-magnetic compatibility and typical tests for better understanding of the studied subject.

Operational parameters of 6-10 kV transmission lines reliability such as number of emergency interruptions, interruption frequency, average duration of interruption are investigated. Histograms of interruption distribution in numbers, average duration of interruption in 6-10 kV networks in months of a year, number of interruptions in hours of a day are constructed. The analysis of the reasons of failures in power supply in 6-10 kV networks is executed.

It is shown that modulating loses significantly influence on resonant properties of generators

The paper contains a method for estimation of electric power economy due to addition of anti-turbulent additives while transporting oil. The proposed method is based on a statistic model constructed according to daily statistics that reflects the established power consumption regimes at an enterprise. A nomograph is developed on the basis of the model using an elasticity factor. The nomograph significantly simplifies engineering calculations.

It is proposed to calculate values of specific consumptions of conventional fuel for generating heat and electric power in a combined electrical installation (Thermal Power Station) on the basis of a thermal and dynamic approach or an exergetic balance of a turbine plant. It is shown that a fuel characteristic of Thermal Power Station is an objective index of a thermal electrical installation

A mathematical model and a program for determination of temperature field dynamics in industrial-scale blanks of unspecified and three-dimensional configuration at thermal treatment according to preset mode are presented in the paper. The paper contains computer-based calculations of temperature field dynamics for a number of blanks at various thermal treatment modes.

The paper analyses influence of the main and auxiliary thermal and mechanical equipment on the reliability of a power unit operation. An estimation of a unit importance in the structural scheme of the power unit depending on its operational time to first failure.

A method for calculation of thermal engineering characteristics of central thermal stations (CTS) and heated buildings is developed by organization of systematic processing of measuring results by standard devices. The given method of calculation is used as a basis for the development of mathematical model for a heat supply system with the purpose to try out the investigated modes using a computer. Approximate results of calculations are given in the form of diagrams and tables.

Analytical solutions and formulae for calculating current-voltage static characteristics of MOS transistors are presented. Calculations are based on verifications of a charge conservation principle which makes it possible to determine the expected parameters of new devices at different process conditions. Computer programs also take into account boundary conditions that take place at the p-n-junction in a drain region and greatly influence on operational modes of transistors. Results have also been used for the analysis of various physical processes concerned with a charge transfer. This cannot be usually carried out by means of existing numerical schemes. Algorithms for determination of an electron mobility and quasi-Fermi levels are developed. Programs also involve analytical formulae obtained earlier by the author for calculations of impurity distribution curves.