scholarly journals Converter for starting motor-generator sets of autonomous locomotives

2021 ◽  
Vol 2021 (4) ◽  
pp. 18-34
Author(s):  
Andrey A. PLESHAKOV ◽  
Keyword(s):  
Practical Importance ◽  
Fuel Mixture ◽  
Battery Life ◽  
Technical Solution ◽  
Device Structure ◽  
Operating Modes ◽  
Generator Circuit ◽  
Repair Costs ◽  
Starter Generator ◽  
Generator Sets

Objective: To confirm the possibility of using a starting converter to spin up the shaft of the motorgenerator set to a speed that ensures stable combustion of the air-fuel mixture in the motor cylinders (starting), as well as of using semiconductor converters based on modern IGBT modules for starting promising motor-generator sets of mainline and shunting locomotives. Methods: The properties, characteristics, and operating modes of starting converters were studied on test benches. Results: The downsides of the currently most commonly used starter-generator circuit for engine starting have been identified. A technical solution has been developed to replace the startergenerator circuit with an inverter starting system using a starting converter for starting the locomotive motor-generator. The device structure has been designed. The basic algorithms of the automatic control system of the starting converter have been implemented. Bench tests of a starting converter prototype have been carried out. Practical importance: The developed technical solution in terms of replacing the starter-generator circuit with an inverter starting system for starting the motorgenerator set of autonomous locomotives makes it possible to increase their reliability by removing the electromechanical drive and replacing a number of engine drive auxiliary camshaft mechanisms (group 69). The inverter starting system will reduce the maintenance and scheduled repair costs, decrease the labor input, and optimize the time-schedule of locomotives. The proposed algorithms for starting the motor-generator set enable increasing the battery life by limiting its starting current, as well as improving the fault tolerance of a locomotive due to the possibility of starting the motorgenerator set at a low battery voltage (lower limit of 45 V).

scholarly journals Salinity Sensing Characteristics Based on Optical Microfiber Coupler Interferometer

Photonics ◽  
2020 ◽  
Vol 7 (3) ◽  
pp. 77 ◽  
Author(s):  
Lingjun Zhou ◽  
Yang Yu ◽  
Huimin Huang ◽  
Yuyu Tao ◽  
Kui Wen ◽  
...  
Keyword(s):  
Sea Water ◽  
Technical Solution ◽  
Structure Parameters ◽  
Sensor Signal ◽  
Device Structure ◽  
Response Sensitivity ◽  
Reading Error ◽  
Seawater Salinity ◽  
Optical Microfiber ◽  
Sensing Characteristics

In this paper, we report a novel and compact sensor based on an optic microfiber coupler interferometer (OMCI) for seawater salinity application. The OMCI device is fabricated by connecting Faraday rotating mirrors to the two out-ports of the microfiber coupler, respectively. The sensor signal processing is based on a wavelength demodulation technique. We theoretically analyze the sensing characteristics with different device structure parameters. Besides, the results show that the date reading error decreases with the thinner waist region and longer arm difference. Through the experiment, the reflection spectra red-shifted as the sea water salinity increased; the highest response sensitivity of the OMCI salinity sensor reached 303.7 pm/‰ for a range of 16.6–23.8‰, and the resolution was less than 0.03‰. This study provides a new technical solution for the development of practical optical fiber seawater salinity sensors.

scholarly journals ORGANIZATION OF POWER SUPPLY OF THE FIRST CATEGORY RECEIVERS FOR PERSPECTIVE CIVIL AVIATION AIRCRAFT

2018 ◽  
Vol 21 (6) ◽  
pp. 54-64
Author(s):  
Alexander V. Kechin ◽  
Alexander V. Levin ◽  
Sergei P. Khaliutin ◽  
Boris V. Zhmurov
Keyword(s):  
Electric Power ◽  
Power Supply ◽  
Electrical Power ◽  
Emergency Operation ◽  
Civil Aviation ◽  
Technical Solution ◽  
Operating Modes ◽  
Advantages And Disadvantages ◽  
First Category ◽  
Supply Systems

The article deals with the issue of providing electric power to the first category receivers in the emergency mode of the power supply systems operation of perspective and modernized aircraft. The analysis of the published scientific works performed both in Russia and abroad, and aimed at solving problems of analyzing abnormal operations mode, synthesizing power supply systems and controlling them in order to prevent dangerous consequences is carried out. The authors considered the ingenious technical solutions aimed at providing the necessary quality power supply for the first category receivers in the emergency operation modes of the aircraft power supply systems for the safe completion of flight and landing. The research analysis and generalization of data on the technical characteristics of units and devices developed by the world's leading manufacturers of aviation equipment and used as emergency sources of electrical power on board modern civil aviation aircraft has been completed. The advantages and disadvantages of each technical solution are determined, as well as limitations to the area of their application are formed. The analysis of perspective emergency sources of the electric power including those, which previously were not applied in aviation because of their insufficient technical perfection, for example, hydrogen electrochemical generators is carried out. Based on the performed analysis, a solution which allows improving the operating modes of the electrical batteries is proposed. The offered solution makes it possible to increase the reliability and durability of electrical batteries, as well as the power supply duration of the first category receivers from them.

scholarly journals Modeling a multifunctional static converter for a hybrid transport power system of traction rolling stock

2021 ◽  
pp. 119-131
Author(s):  
Аleksey Е. TSAPLIN ◽  
Keyword(s):  
Power System ◽  
Practical Importance ◽  
Power Converter ◽  
Rolling Stock ◽  
Control Algorithms ◽  
Operating Modes ◽  
Static Power ◽  
Management Functions ◽  
Hybrid Circuit ◽  
Storage Units

Objective: Modeling of processes in a multifunctional static converter. Methods: Methods for calcu- lating electrical circuits and simulation in the MATLAB software using the Simulink library package are applied. Results: The circuit solutions have been chosen and the development of control algorithms for a multifunctional static power converter for a hybrid transport power system has been carried out. A multi-convector hybrid circuit with two power storage units was chosen for the analysis of the work. Practical importance: The developed model makes it possible to assess the rational power management functions of a hybrid transport power system for various operating modes, confirming the expediency of configuration and choice of circuit solutions when creating a converter for a hybrid transport power plant.

Energy efficient bio positive designs in the buildings of civil purpose for the conditions of St. Petersburg City

2017 ◽  
pp. 44-50
Author(s):  
Anatoly Kuznetsov
Keyword(s):  
Energy Efficiency ◽  
Housing Stock ◽  
Residential Buildings ◽  
Practical Importance ◽  
Experimental Studies ◽  
Winter Period ◽  
Mean Annual Temperature ◽  
Technical Solution ◽  
Climatic Parameters ◽  
Constructive Solution

Objective: Development of technical solutions for improving energy efficiency in residential buildings. Methods: Field experiment, thermal inspection of residential buildings. Results: In the conditions of rising global mean annual temperature over the last century, changed climatic parameters of St. Petersburg city. The duration of the winter period decreased by 13 days compared to the first half of the XX century due to the earlier onset of spring. The shift of the winter end has shifted to a colder part of the year and beginning remained unchanged. The winter in the district of St. Petersburg became colder. The change of climatic parameters of St. Petersburg affects the efficiency of the housing stock built since the late 90s. using the technology of monolithic housing construction. In the work conducted thermal survey of residential buildings of monolith structures in St. Petersburg. The result revealed the following defects: the formation of cold bridges in the construction of the pairing of the slabs with wall enclosing structures; disturbance of temperature and humidity conditions in residential areas; a deterioration of living conditions in the apartments; in some cases, the growth of education fungi. To create favorable conditions for human habitation designed a constructive solution that improves the thermal performance of the exterior walls. The technical solution is the use of the valve, in the thickness of the wall and provides or prevents the penetration of outside air in the air layer. Practical importance: The application of the proposed constructive solution after additional experimental studies will improve the energy efficiency of residential buildings in the context of changing climatic parameters.

scholarly journals ON THE ISSUE OF IMPROVING THE QUALITY OF ELECTRICITY IN THE TRANSIENT OPERATING MODES OF MARINE DIESEL GENERATOR SETS

2021 ◽  
Vol 7 (3(84)) ◽  
pp. 23-26
Author(s):  
A. Pronina
Keyword(s):  
Inertial Mass ◽  
Transition Process ◽  
Sinusoidal Voltage ◽  
Diesel Generator ◽  
Significant Frequency ◽  
Operating Modes ◽  
Static Converters ◽  
Marine Diesel ◽  
Generator Sets

The operation of diesel generator sets (DGS) under conditions of significant frequency deviations with sharp load changes is investigated. Systems containing powerful static converters in transient operating modes experience a sharp deterioration in the quality of electricity in terms of non-sinusoidal voltage. The use of filtercompensating devices in conditions of frequency deviation is not effective. In order to improve the quality of the transition process, it is proposed to reduce the speed (frequency) dips by increasing the inertial mass of the DGU by hanging the flywheel.

scholarly journals Modeling of formation regularities of conical surfaces

2021 ◽  
Vol 66 (4) ◽  
pp. 430-439
Author(s):  
A. S. Kozeruk ◽  
A. A. Sukhotsky ◽  
R. O. Diaz González ◽  
M. I. Filonova ◽  
V. O. Kuznechik ◽  
...  
Keyword(s):  
Optimization Technique ◽  
Experimental Studies ◽  
Side Surface ◽  
Point Of View ◽  
Group Method ◽  
Technical Solution ◽  
Technological Equipment ◽  
Operating Modes ◽  
Conical Surfaces ◽  
Flat Tool

The scheme of processing conical surfaces by grinding them to a flat tool is considered and a technical solution for the implementation of such processing is proposed. Using the created device allows implementing the group method of forming conical parts with a deviation of the generatrix of the cone from straightness of not more than ± 0.00012 mm. A mathematical model of the patterns of removal of stock from a conical part with a flat tool is developed. A formula is obtained for calculating the modulus of the sliding velocity at any point on the processed conical surface, which implements engineering methods for controlling the shaping of conical parts without conducting preliminary labor-intensive experimental studies. An optimization technique for the adjustment parameters of technological equipment was proposed. The most effective axicon processing modes were revealed at the stages of preliminary, medium and fine grinding, as well as at the polishing stage, depending on the technological heredity of the workpiece from the point of view of distribution of the stock to be removed over its surface. It has been established that changes in the eccentricity between the axes of rotation of the tool and the faceplate as well as the amplitudes of the reciprocating rotational movements of the latter practically do not affect both accuracy and processing productivity, therefore, in practice, these parameters can not be optimized, but their average values can be assigned. The operating modes of the basic lever grinding and polishing machine are established, at which the required accuracy of the working surface of the tool is provided, which directly affects the straightness of the generatrix of the cone. Studies of the regularities of the shaping of the side surface of a conical lens in the conditions of free grinding are carried out and the adjustment parameters of technological equipment that affect the quality and productivity of the processing process are determined.

scholarly journals Devising the technology for localizing environmental pollution during fires at spontaneous landfills and testing it in the laboratory

2021 ◽  
Vol 6 (10 (114)) ◽  
pp. 40-48
Author(s):  
Ivan Bondarenko ◽  
Igor Dudar ◽  
Olha Yavorovska ◽  
Olha Ziuz ◽  
Sergii Boichenko ◽  
...  
Keyword(s):  
Environmental Pollution ◽  
Urban Areas ◽  
Aqueous Suspension ◽  
Environmental Safety ◽  
Household Waste ◽  
Technical Solution ◽  
Practical Application ◽  
Environmental Consequences ◽  
Operating Modes ◽  
Waste Storage

This paper reports an analysis of current issues related to storing solid household waste, and, specifically, the problem of environmental pollution when unsorted solid household waste (SHW) is ignited. A technology has been developed to improve environmental safety and ensure a reduction in the anthropogenic load on the atmosphere, hydrosphere, and lithosphere in the event of fires at the sites of solid waste storage. The operation of the proposed equipment, taking into consideration all the provided operating modes and additional options, is energy-saving and automated (or semi-automatic), which makes it especially relevant under modern conditions. The technology significantly improves the efficiency of the processes to eliminate the ignition of SHW and localize their environmental consequences for the territories adjacent to landfills. Laboratory tests were carried out, which proved the effectiveness of practical application for the designed equipment of a new environmentally active adsorption mixture for the purpose of cleaning the waste filtrate, as well as its use for the formation of an anti-filtration screen in the mound of SHW. Experiments have shown that the tested sample of the aqueous suspension of the proposed environmentally active mixture adsorbs calcium (by 92 %), overall iron (by 91 %), overall phosphorus (by 75 %), zinc (by 31 %), and ammonium (by 19 %). This leads to a decrease in the overall toxicity of the solution and indicates the possibility of improving the environmental safety of waste fires when operating the proposed technical solution by purifying the filtrate released during fires in landfills. The reported results, specifically, the technology for localizing the environmental consequences of uncontrolled waste ignition could be used in the process of modernizing the technical support for sanitary treatment schemes in urban areas.

scholarly journals Evaluation of the efficiency of cavitation-jet deaerator in condensate return systems of remote external consumers of thermal power plants

Vestnik IGEU ◽  
2019 ◽  
pp. 5-13
Author(s):  
Yu.E. Barochkin ◽  
A.Ya. Kopsov ◽  
G.V. Leduhovsky ◽  
S.I. Shuvalov
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Technical Solution ◽  
Thermal Power Plants ◽  
Superheated Water ◽  
Regulatory Requirements ◽  
Practical Applications ◽  
Capital Costs ◽  
Operating Modes ◽  
Nominal Capacity

Thermal power plants (TPPs) operate technological systems for the steam condensate return from remote external consumers. In such systems, it is necessary to protect the metal from corrosion. This will allow ful-filling the regulatory requirements for the concentration of iron compounds in the condensate entering the power plant. Such systems do not use thermal deaerators operated by using heating steam. The aim of the undertaken study is to assess the efficiency of superheated water deaerator use in such conditions, in par-ticular cavitation-jet deaerators. It means determining the effect of a new element of the system – the de-aerator – on the normalized chemical parameters of the returned condensate. A mathematical model of superheated water deaerators is used. The employed model is based on the theory of similarity of heat and mass transfer processes. The methodology for calculating the corrosion rate of return condensate pipelines was used, as well as experimental data on medium pressure TPPs. The efficiency of cavitation-jet deaerators in condensate return systems of external consumers has been estimated. A mathematical description of the system has been developed, which allows determining the required performance of deaerators and the required ratio of water recirculation through them in each mode. Recommendations for effective practical applications of the proposed technical solution have been developed considering the actual conditions at thermal power plants. It is advisable to install a deaerator according to the recirculation scheme through the condensate collection tank. This scheme, compared to a sequential scheme, enables to reduce capital costs and ensure that the deaerator operates in the highest efficiency mode. The choice of the nominal capacity of deaerators should be carried out taking into account the graphs of the change in the flow rate of incoming condensate and the concentration of dissolved oxygen in it during the day. In most operating modes of the system, it is possible to ensure compliance with the regulatory requirements for the mass concentration of corrosion products in the condensate returned to the TPP. The obtained results can be used in the design of new and improving the efficiency of existing TPPs that supply steam to external consumers.

scholarly journals Justification of the operating modes of the needle disk of a new design

2020 ◽  
Vol 1 (4) ◽  
pp. 70-75
Author(s):  
A.N. Shmidt ◽  
◽  
A.A. Kem ◽  
M.S. Chekusov ◽  
D.E. Kuz'min ◽  
...  
Keyword(s):  
Crop Residues ◽  
Sandy Loam ◽  
Angle Of Attack ◽  
Soil Layer ◽  
Perennial Grasses ◽  
Technical Solution ◽  
Soil Cultivation ◽  
Operating Modes ◽  
Loam Soil ◽  
Working Bodies

The preservation and accumulation of productive soil moisture in areas with insufficient moisture and subject to wind erosion does not lose its relevance. Known disc needle-like working bodies of rotary harrows, intended for surface treatment on stubble backgrounds, are mainly aimed at loos-ening the upper soil layer. An incorrectly selected mode of using existing needle harrows is danger-ous by excessive spraying and drying out of the surface of fertile soil. In this regard, there was pro-posed a new technical solution for a needle disk with a changing shape of needles, which makes it possible to loosen the top layer of soil from making holes on the surface of the field. A tillage tool with needle discs consists of a hub with needles fixed on it. The disc is installed afrontal, each nee-dle is made of a variable shape, the first half made from the base of the needle is square, and the second half is pyramidal with a top at the end of the needle. The use of such needle discs with nee-dles, which more easily penetrate the soil make it possible to efficiently chop up crop residues and loosen the soil, which improves the quality of soil cultivation. The tests of the new needle disk against the background of perennial grasses made it possible to substantiate the main operating pa-rameters of the new working body. For sandy loam soil with a hardness of 14.5 kPa with an ag-rophone of perennial grasses, such as awnless rump and alfalfa, it was found that the maximum pa-rameter for moisture accumulation will be achieved at a speed of 7 km / h with an angle of attack equal to 0 °, and loosening at a speed of 9 km / h with an angle of attack of 16 °. A rational parame-ter, at which not only moisture accumulation occurs, but also high-quality soil cultivation, is achieved when the angle of attack is set to 4 ° and the speed of the unit is 7 km / h.

Technical solutions for prevention thermal pollution of ponds within urbolandscape

2017 ◽  
pp. 60-66
Author(s):  
Tamila Titova ◽  
Rasul Akhtyamov ◽  
Elina Nasyrova
Keyword(s):  
Heat Exchanger ◽  
Water Supply ◽  
Power Plants ◽  
System Analysis ◽  
Cold Water ◽  
Practical Importance ◽  
Thermal Pollution ◽  
Technical Solution ◽  
Domestic Water ◽  
Technical Solutions

Objective: The development and scientific substantiation of technical solutions for prevention thermal pollution of cooling pond of power facilities. Methods: Patent study, methods of system analysis. Results: Found that cooling ponds in which discharged heated water from electric power facilities, leading to thermal pollution. In connection with which the waters become unfit for housing and communal services, namely drinking and domestic water supply and recreational water use. The existing technical solution for preventing thermal pollution of water bodies have a number of drawbacks, namely low reliability due to the complexity and bulkiness of the structure; limited functionality due to not fully using the heat medium and long cold water. On the basis of the patent study of existing methods of reducing thermal pollution, the developed heat exchanger heated waters of power objects (patent RU № 134621). Designed heat exchanger characterized by enhanced functionality available ways to prevent thermal pollution due to the use of thermal energy of the heated waters of power plants for heating of cold water and correspondingly cooling the heated waters. Practical importance: The proposed by authors technical solution allows utilizing the heat energy of the heated waters of power facilities before discharge into cooling ponds. Thus, the heat exchanger prevents thermal pollution of the reservoir and consequently provides a desired level of water quality for water supply and supplies the consumers with warm water, i. e., contributes to several tasks of housing and communal services.

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