The high speed of solar energy development in the
modern world allows us to assert that in the near
future it will become one of the main sources of
electricity. The authors describe a classification of
solar power plants, which can be of two types –
thermodynamic and photovoltaic, as well as the
features of design and operation of these plants. There
is a structural and schematic solution of autonomous
solar power stations and ones operating in parallel
with the external power grid. The features of their
design and operation, including the main advantages
and disadvantages were shown. It is shown that to
improve the reliability, including uninterrupted power
supply, a promising direction is the development of
combined systems which in addition to the solar
power plant may use wind power, gas or diesel
power, etc. In addition, such stations may provide
power from the external power supply. We have
given one of the variants of structural designs of
combined systems of energy and disclosed
recommendations for the design of energy-efficient
combined systems of power supply, made using
renewable and conventional sources of electricity.
The final version of the combined system of
electricity supply and the degree of participation of
traditional and renewable energy sources in electricity
production is determined on the basis of the analysis
of the energy balance and electromagnetic
compatibility of the main functional elements of the
system
The aim of the work is theoretical and experimental
confirmation of the possibility of improving the rate
of acceleration of tractor units due to installing of
elastic-damping mechanism with variable stiffness in
tractor transmission. Speed tractors application in
agricultural production meets a number of difficulties
associated with the unsteady processes during
acceleration of machine and tractor units. The resulting
large inertial loads when accelerating result in
loss of engine power, due to which the machinetractor
unit is operating at reduced performance and
efficiency. An analysis of published studies shows
that the acceleration performance of tractor units is
greatly influenced by the stiffness and damping
properties of the transmission of energy resources.
To provide smooth acceleration of the unit it is proposed
to install elastic-damping mechanism with
variable stiffness in tractor transmission. As a result,
the tension of the acceleration process decreases. The
results of analytical and experimental studies on the
effect of elastic-damping mechanism installed in the
class 5 tractor transmission, on acceleration capabilities
of tractor units are given. The optimum parameters
of elements of elastic-damping mechanism with
variable stiffness for class 5 tractors are determined.
It is proved that the use of elastic-damping mechanism
with a variable stiffness in the tractor transmission
improves acceleration indicators
The article is devoted to solving one of the major
problems in electric power industry, which is to
simplify and improve the accuracy of simulation and
calculation modes of complex electrical systems with
using the frequency characteristics of the elements of
the power system in generalized vector space. Article
has an exploratory character, which is expressed that
mathematical models of static elements of an electrical
network are considered in the form of transfer functions
of dependence of conduction on the frequency. A
number of the provisions of article has scientific
originality which is in the approach to the choice of the
coordinate system for modeling static elements. It is
offered the mathematical models air and cable
transmission lines, generalized load, single reactors
generalized vector space for analysis of steady and
transient modes. As an example was calculated family
of real and imaginary parts of the frequency
characteristics of the AC-70 line with different values
of the length, lines with different section (AC-70, AC-
95, AC-120), generalized load with different ratios of active and reactive power, various types of single
reactors. Offered mathematical models allow exploring
different symmetric modes of electric networks using
more efficient mathematical apparatus
The article contains a scientifically based approach to
assessing and improving the reliability of DMU "Frigate"
in the conditions of the Rostov region. The studied
parameters for the elements with the lowest resource
were: mean time between failure, mean time to repair,
probability of failure, the parameter flow of failures,
failure rate, actual and allowable factors of readiness.
The analysis of the main faults of DMU "Frigate",
identified nodes and elements, characterized by the
low reliability, for which the dependences of probabilities
of failure-free operation, as well as the dependence
and developed the procedure for calculating the optimal
duration of recovery of failed elements, to ensure
acceptable availability. Statistics on major faults refuse
items were collected over the three irrigation seasons
from 2013 to 2015, were investigated failures due to
wear of the elements for 17 irrigation machines. As a
result of the research we developed mathematical apparatus
of calculation and the comparative assessment
of the readiness of the parks sprinklers of various
farms to perform their processing functions at the same
and different number of machines. We obtained the
dependence for determining the allowable duration of
the recovery elements that will allow you to determine
the main directions of improving the reliability of
DMU "Frigate" during the operational phase
The article has a research character which is expressed through the analysis of ways and means of mechanization for harvesting of cucumbers, and also through the works of scientists on the studied subject. Vegetable growing is an important branch of agricultural production. Among a set of vegetable plants the increasing significance is attached to cultures production of which contains physiologically active agents. Solanaceous vegetables belong to these cultures. In Russia, vegetables on an industrial basis are cultivated in the south of the country. Everywhere in Russia crops of vegetables are reduced. It is explained by high costs of production, especially on harvest that at the general deficiency of manual skills leads to reduction of the areas, violation of technology of cultivation and harvest and, respectively, to decrease in productivity. In the conditions of import substitution of foreign agricultural production and increase in the areas of landing of vegetable cultures in the Russian Federation for creation of a safety cushion of food in the conditions of food embargo, undoubtedly, there will be required the maximum mechanization of technological process of harvesting of vegetables. The article presents the most important results of new types of designs of machines for harvesting of vegetables and cucumbers in particular, as well as problems of use of modern machines for cleaning cucumbers and vegetable cultures
The article deals with the reliability of the functioning of the equipment of the power supply substation, and the determination of the probability of uninterrupted supply of electricity to consumers. The following are presented: models of failures of separators, models of short-circuit failures, models of failures of disconnectors. Two statistical series for sudden and gradual failures are singled out. The reliability theory is shown as the main distribution of fail-safe time for sudden failures. The conclusions on the presented models are made and the suggestions on introduction into production are given. According to the presented models, it is possible to judge the reliability of the station's operation, which is necessary for implementing measures to improve the reliability of electricity supply in network companies
In this article, there are descriptions of ventilation
systems of municipal and industrial buildings. We
consider the scheme of natural ventilation and
ventilation with mechanical drive. In agriculture
production, processes accompanied by the releasing
into the air of premises various harmful substances:
gases and vapors, excess of heat and moisture. The
source of the fumes and gases are various technological
processes. People, animals and birds in the premises,
release carbon dioxide and other gases. Sources of heat
gain are the people, animals and birds, solar radiation,
production equipment and so on. For optimization of
parameters of the air environment, satisfying the
hygienic requirements, need to install ventilation. The
ventilation system – it is a set of devices for handling,
transportation, supply and removal of air. The
advantage of this article is the systematization of
ventilation systems of production premises. We have
identified the main flows of indoor air and placement of
exhaust shafts. Greatest interest are the systems
operating year-round or during the heat period and
exhaust systems equipped with control devices in the
form of a throttle valves or gate valves and a device for
cleaning the air. We give sufficient attention to the
thermal regime of premises, heat losses and heat gain
through protecting designs. We indicated that a
significant effect on the thermal state of premises might
be provided by humidity level of fences, as well as
potential of heat and moisture transfer
In this article, we have examined the methodology of
acoustic measuring with the purpose to create safety
conditions for the activity of agricultural machines
operators, in foremost harvesters and tractors. We
should underline that such studies are based on the
state standards that are aimed at improving the level of
comfort of the activity of the operators of tractors and
harvesters and maintaining their working capacities.
Therefore, there is a need for a thorough analysis of
the current regulatory legislation (standards that are
applied) in combination with analysis of mathematical
support of measuring devices (sound level meter).
Besides, there is a need for creating strict sequence of
actions of the sound level meter operator (algorithm)
in combination with the method of conveying
information that is adapted to the experiment. At the
enterprises, organizations and establishments control
of the noise level at working places is checked no less
than once a year. The State Standard 12.4.095-80
provides the basis for measuring, position of the
control point in the booth, the frame and
characteristics of measuring, mode of activity of
engines and parts of harvesters, the amount of
measurement samples (3 precise measurements),
estimation of measurements and their correction,
equipment, methods of measuring the results,
temporary characteristics of measuring by the sound
level meter in “slow” mode and frequency correction
The creation of better conditions for the cultivation
of plants is carried out by means of mechanical
impact on the soil working bodies of machines and
tools, that is, the so-called tillage. Its importance in
the conditions of intensive agriculture cannot be
overemphasized. The use of each scientifically based
crop rotation system of soil tillage is a necessary
condition for further growth of crop yields and
improve soil fertility. Tillage determines the
processes of reproduction, fertility regulation soil
modes, degradation processes and soil conservation.
Important and how self-administration in the system
of minimum tillage, and in addition to the deeper
treatment of soil under traditional agricultural
technologies is superficial and shallow tillage. Disc
harrows are the most applied machine for the
implementation of surface and shallow soil
treatment, performing a loosening of topsoil, leveling
the field surface, the destruction of soil crust,
crumbling lumps of soil, weeding, seeding and
fertilizer. This article describes the design features of
domestic and foreign disc harrows. We have given
their technical characteristics, and consider the
operational and technological parameters
Currently one of the promising areas to significantly
improve efficiency of energy saving is the
introduction of renewable sources of energy into the
energy system. In the field of solar energy, we
consider solar photovoltaic power plants with direct
conversion of solar radiation into electricity using
solar panels as the most promising ones. The article
examines the main factors that reveal the prospects
of applying solar photovoltaic power plants. It also
discusses the main advantages and disadvantages in
comparison with traditional and other renewable
energy sources. To improve the operational and
technical characteristics of solar power plants in
their structure significantly, it is proposed to use new
components. Stand-alone inverters for single-phase
transformers with rotating magnetic field will reduce
the number of power electronic devices in the
conversion circuit; they will simplify the system of
control and protection, reduce electromagnetic
interference and improve overall efficiency and
reliability of the converter of the solar power plant.
In addition, the modular design of solar power plants
will also increase the reliability of the power system
due to redundancy of the major functional elements.
It is also important that the construction of solar
power plants in a modular way enhances
maintainability of the system, it significantly reduces
the time for maintenance and troubleshooting in
emergencies; it simplifies the task of changing its
structure depending on requirements of users. The
article reveals peculiarities of work and the main
benefits from the application of solar photovoltaic
power plants