MODELING OF THE PROCESS OF ELECTROMECHANICAL CONTROL OF GAS DISTRIBUTION OF AN ELECTRIC ENERGY GENERATOR WITH AN INTERNAL COMBUSTION ENGINE

The use of generators at different load levels allows you to use part of the rated power of the engines, by reducing the speed of the internal combustion engine, thus reducing fuel consumption and increase the overall efficiency of the system as a whole. However, it should be noted that the optimal operation of the internal combustion engine at fixed gas distribution parameters is possible only at a certain engine speed. Reducing the engine speed leads to a deterioration of the filling of the fuel-air mixture and the release of exhaust gases from the engine, accompanied by the intake of exhaust gases into the intake manifold and the emission of part of the fuel mixture into the exhaust pipe. The paper presents the results of the study of generator parameters and the general concept of creating an autonomous power supply control system based on an internal combustion engine in order to reduce the specific indicators of electricity generation. The expediency of regulating the power level of an internal combustion engine has been experimentally proved. To achieve this goal, it is proposed to adjust the opening and closing angles of the internal combustion engine with a solenoid valve. The use of this system allows to reduce the specific costs by more than 4 times when generating electricity with low generator load. Based on the phase distribution diagram of the internal combustion engine, the dependence of the change of the opening and closing angles of the inlet and outlet valves on the power of the autonomous energy source is proposed.

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GAS DISTRIBUTION PHASES HYDRAULIC CONTROLLED INTERNAL COMBUSTION ENGINE VALVES

Vestnik of Kazan state agrarin university ◽

10.12737/2073-0462-2022-47-52 ◽

2022 ◽

Vol 16 (4) ◽

pp. 47-52

Author(s):

Nail Adigamov ◽

Andrey Negovora ◽

Larisa Zimina ◽

Alexey Maximov

Keyword(s):

Internal Combustion Engine ◽

High Speed ◽

Combustion Engine ◽

Hydraulic Drive ◽

Internal Combustion ◽

Valve Timing ◽

Gas Distribution ◽

Time Section ◽

Engine Valves ◽

Opening And Closing

The efficiency of an agricultural car or tractor depends on the characteristics of the engine determined by the gas distribution mechanism (GRM). Traditional timing with fixed valve timing does not provide high-quality gas exchange at all engine operating modes. The aim of the work is to improve the characteristics of the engine by using the hydraulic drive of the timing valves. The drive allows you to turn off individual valves, set the moments of their opening and closing in an arbitrary way, provide several triggering of the internal combustion engine valves during the operating cycle. The drive is controlled by an electronic control unit (ECU). The advantage of the drive is its ease of integration into the internal combustion engine. The hydraulic drive ensures that the timing valves are lifted to a height of about 14 mm. The law of displacement of the valve, revealed experimentally, is close to trapezoidal. The use of a hydraulic valve drive has a positive effect on the "time-section" factor in the area of low and medium crankshaft rotational speeds. The increment of the factor "time-section" is due to the significant speeds of opening and closing the valves. Due to the peculiarities of the kinematic characteristics of the movement of the valves when using a hydraulic drive for their movement, the use of serial phases of gas distribution of the engine is impractical. Numerical modeling of the operation of the internal combustion engine determined the regularity of the change in valve timing from the high-speed operating mode of the engine. Optimization criterion is the achievement of maximum engine power. When choosing the valve timing, the possibility of meeting the intake and exhaust valves with the engine piston was excluded. The use of optimal phases leads to an increase in power up to 4.5% at a low crankshaft speed. With an increase in the speed mode, the increase in power decreases, and with a high frequency of rotation of the crankshaft, its slight decrease (1.4%) is observed. An increase in torque, up to a power utilization factor of 0.9, and its subsequent decrease, allow stabilizing the vehicle speed on a road with variable resistance. An increase in the working pressure in the hydraulic drive of the valves makes it possible to intensify gas exchange even at a high speed of rotation of the crankshaft

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Small Cogeneration Unit with Heat and Electricity Storage

Energies ◽

10.3390/en14082102 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2102

Author(s):

Josef Stetina ◽

Michael Bohm ◽

Michal Brezina

Keyword(s):

Internal Combustion Engine ◽

Cooling System ◽

Combustion Engine ◽

Catalytic Converter ◽

Storage System ◽

Internal Combustion ◽

Energy Storage System ◽

Balance Model ◽

Exhaust Pipe ◽

Water Storage Tank

A micro cogeneration unit based on a three-cylinder internal combustion engine, Skoda MPI 1.0 L compressed natural gas (CNG), with an output of 25 kW at 3000 RPM is proposed in this paper. It is a relatively simple engine, which is already adopted by the manufacturer to operate on CNG. The engine life and design correspond to the original purpose of use in the vehicle. A detailed dynamic model was created in the GT-SUITE environment and implemented into an energy balance model that includes its internal combustion engine, heat exchangers, generator, battery storage, and water storage tank. The 1D internal combustion engine model provides us with information on engine start-up time, actual effective power, friction power, and the amount of heat going to the cooling system and exhaust pipe. The catalytic converter was removed from the exhaust pipe, and the engine was always operating at full load; thus, engine power control is not considered. An energy storage system for an island operation of the entire power unit for a large, detached house was designed to withstand accumulated energy for a few days in the case of a breakout. To reach a low initial system cost, the possible implementation of worn-out battery packs toward emission reduction in terms of the second life of the battery is proposed. The energy and emission balance are carried out, and the service life of the engine is also discussed.

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