In this work, the diagram of scalar control of asynchronous electric drive is improved with the aim of expanding the control range of the motor speed. The optimal control algorithm with a voltage stator, comprising the application of a voltage boost to increase the overload capacity of the motor at low frequencies control. Presented in a simple and easily reproducible method of formation of parameters of the control algorithm, suitable for engineering calculations.
A diagram and description of operation of the device to control and prevent overheating of electric motors in harsh environments in the enterprises of the agroindustrial complex.
The choice of energy source is usually based on technical, economic and environmental comparisons of the different alternative options considered. The paper presents the results of a comparative economic assessment of the life cycle of wind, solar power stations and mini-HPPs with an installed capacity of 30 kW, offered for operation in the Nizhny Novgorod region. It is shown that an estimate of the costs of the life cycle of renewable energy sources can be used for the feasibility study of the project with a view to rational use of electricity costs.
Networks with voltage up to 1 kV (the Guild) are a critical link in the power system and represent a large area in the design of the electrical part of industrial enterprises. Power quality is one of the most important requirements of the system of production, transmission and consumption of electricity. In the presence of asymmetry of voltages and currents of phases a number of adverse events. The paper presents the negative impact of unbalance and methods of their elimination in the power system.
The basic regulatory requirements imposed on the main and additional equipotential bounding systems (EBS) is shown in the article. It is shown: what exactly can be used as protective conductors of these systems, what should be their cross section, how to lay and carry out the connection of protective conductors. It is given a list of the documents transmitted by the installer organization to maintenance of electrical installations, also a content of the grounding system passport. The activities directed to test of EBS, which include: visual inspection; checking structural condition; mea- surement of the contact connections resistance between the grounding element and an element of EBS are described. Examples of EBS inspections are given. The basic disadvantages of the implementation of EBS is formulated. The main conclusion: testing of the equipotential bounding systems it is advisable to combine with testing of the grounding system and lightning protection systems.
In article safe management of nuclear power plants is considered, conditions of subcriticality and a nadkritichnost of the nuclear reactor, a stock of reactivity, the accidents connected with damage of fuel elements (TVEL) and also the history of nuclear power numbering violation of balance between thermal emission and the heat sink are described. “General provisions of safety of nuclear power plants” are provided.
The paper discusses an example of calculation of parameters of energy storage when connecting solar power into the grid. The prospect of the development of alternative energy in the Crimean Peninsula with the growth of electricity consumption and improve the quality of energy produced by the energy storage, is included in the internal circuit of power plants based on renewable energy.
The questions of an evaluation technical insulation resource of the submersible electric motor under the influence of impulse overvoltages are considered and methods of perfection of protection of the submersible electric motor are offered. The expediency of installing submersible surge arresters at the terminals of a sub- mersible electric motor is substantiated. The dependence of the multiplicities of voltages and currents on the resistance value of the earthing electrode is analyzed.
The article explores the possibility of using contact sensors of defects for control of insulation of winding wires, for use in an information signal induced in the conductors of circuits controlled by the EMF. The developed method of control of defects in the enamel insulation of wires to determine the number and length of the defective areas in enamel insulation moving with any variable speed wire. The proposed scheme of meter defects and the principle of its work. The identified systematic error in the control defects length due to the finite size of the sensor defects and the method of its elimination.
