current position:the entire unit generally consists of diesel engines, generators, control box, fuel tank, starting and controlling the storage battery, protective equipment, emergency cabinet and other components
1. engine (engine)
2. generator (alternator / generator)
3. control system (control panel / control system)
4. start the motor start motor
5. start battery start battery (battery connected to the motor above)
engine and generator connection: 1, flexible connection (with the coupling connecting two parts) 2, steel connection, have high strength bolts connecting the generator steel sheet disk is connected to the engine flywheel, then connected on the public bottom shelf, then matched with a variety of protective effect sensor (oil probe, temperature probe, oil pressure sensor, etc.), by the control system to display the working status of various sensors. control system is connected by cable to the display data generators and sensors
generator set works:
diesel engine driven generator running, diesel fuel energy into electricity
in the diesel engine cylinder through the air filter clean filtered air atomizing nozzle jet of high-pressure diesel mix, squeezed in under the piston upward, the volume is reduced, the temperature rises rapidly, reaching diesel ignition. diesel fuel was ignited, severe burning gas mixture, rapid expansion of volume, pushing the piston down, called the 'do work'. each cylinder for a certain order of power, acting on the piston rod thrust through crankshaft rotation into a pushing force, thus boosting the crankshaft rotation.
the brushless synchronous ac generator and diesel engine crankshaft coaxial installation, you can use the rotary diesel engine driven generator rotor, the use of 'electromagnetic induction' principle, the generator will output induced electromotive force, by closing the load circuit can generate electricity .
here, only the most basic principle of the generator set. to be usable, stable power output, but also a series of diesel engines and generator control, protection devices and circuits.
if the continuous running for more than 12h, the output power will be lower than the rated power of about 90%
diesel engine diesel generator is generally four-stroke single-cylinder or multi-cylinder diesel engines, the following work i only talk about the basic principles of the single-cylinder four-stroke diesel engine: diesel engine starting diesel engine crankshaft is rotated through human or other power piston cylinder closed at the top in up and down reciprocation. four stroke piston complete in motion: the intake stroke, compression stroke, combustion, and for power (expansion) stroke and an exhaust stroke. when the piston moves down from the upper intake valve opens, the air filter filtered fresh air into the cylinder to complete the intake stroke. by the upward movement of the piston, intake and exhaust valves are closed, the air is compressed, the temperature and the pressure increased, the compression process is completed. pistons will arrive at the vertex of the filtered injector fuel was sprayed into the combustion chamber is mixed with air temperature and pressure of immediate self-ignition combustion, the formation of high pressure pushes the piston downward for power, push crankshaft rotation to complete the work power stroke
diesel generator set description: manual operation
1, the manual should be checked before the diesel generator fuel, oil, cooling water is appropriate. shortage should be promptly added. units should be no oil spills, leaks phenomenon.
2, diesel generator should be automatic controller automatic control switch to the middle position.
3, open the starting circuit of the key, the right to continue to twist the key to make the engine starts, after a successful start, turn the key back to the charging station.
4, diesel generator sets down, the key should be set aside in time back to the middle position
diesel generator set description: automatic operation
1, in the city electricity normal circumstances, the automatic controller automatic control button up switch to 'auto' position. at this prohibition manually start the engine. when the mains power, diesel generators started automatically, and by the ats automatically switch power to the grid.
2, after the diesel generator automatically starts running, should be the key switch to the charging position.
3, after the mains call, the unit will automatically stop. after the shutdown should be the key switch to the neutral position to prevent the battery down electricity, affecting the next use
diesel generator description: maintenance, maintenance
1, diesel generator running 60 hours after the need to replace the oil, clean diesel filter, air filter.
2, should always check the battery electrolyte, should be insufficient to replenish.
3, you should always check the belt tension, the tension adjustment mechanism to maintain tension.
4, the cold season should open water heating and oil heating switch the unit to maintain a certain temperature, to ensure the proper use of diesel generator sets
the combustion process:
1. combustion preparation phase (ignition delay)
from the fuel injected into the fire began to burn the preparatory phase of this period. at this stage, the fuel to be heated and evaporated, diffused and mixed with the air flow and other physical preparation, and the preparation of chemical decomposition, oxidation processes.
2. fast burning stage
from the fire began to appear at this stage maximum pressure within the cylinder when ended. when a small amount of diesel fuel on fire, combustible mixture continued to increase fire quickly spread, burning speed, heat release rate is high. pressure and temperature inside the cylinder dramatically. but when the pressure rises too fast, it will crank linkage severely impact loads, and with a sharp percussion, diesel engine explosion rough, this situation should be restricted. for the diesel and steady, growth rate should not exceed the maximum pressure 292kpa ~ 588kpa / 1 ° (crank angle)
3. primary combustion stage (slow ignition)
stage combustion pressure points to emerge from the outbreak of the maximum combustion temperature phase occurs mainly between points. this phase is characterized by injection has ended, most of the fuel combustion in the meantime, the release of about 80% of total calories, the gas temperature rises to the highest point. however, due to the down piston, the cylinder volume increases, so little change in pressure inside the cylinder. oil at the end of this phase.
4. after combustion stage
after the combustion stage
points from the maximum combustion temperature to the end stage combustion ended. at this stage, already consume a lot of oxygen, the late injected fuel would not mix with enough oxygen for combustion, combined with further down the piston, the cylinder pressure and temperature have a greater decline, the combustion conditions worsened, resulting in incomplete combustion of fuel, exhaust black smoke phenomenon occurs so that the relevant parts of the heat load increases, the impact of the economy and the life of the diesel engine, it should minimize fuel combustion period
noise generator set mainly by the exhaust noise, mechanical noise, combustion noise, cooling fan and exhaust noise, into the wind noise, generator noise, ground vibration and noise
mechanical noise: mechanical noise is dominated by the moving parts of the engine vibration gas pressure and inertia forces caused by periodic changes during operation or mutually impact generated (noise noise piston crank linkage mechanism, with gas agencies transmission gear noise, mechanical vibrations caused by unbalanced inertia force and noise)
combustion noise: structural vibration and noise of diesel fuel in the combustion process in the cylinder combustion noise level is very high, however, higher engine structure in most parts of the steel, its more in the high-frequency vibration frequency area, because of the sound wave propagation frequency response does not match, because you can not successfully came in low frequency high peak cylinder pressure level, while the high frequency cylinder pressure level is relatively easy to spread.
unit fan noise is generated by the eddy current noise, noise, and mechanical noise rotating components. exhaust noise, aerodynamic noise, fan noise, mechanical noise will spread out through the exhaust passage
the role of the inlet channels are: to ensure the normal operation of the engine and to the unit itself, to create a good thermal conditions
optional program should be able to be done both to effectively reduce ambient noise, but also organize good air flow inside the room to meet the needs of generators to run air flow, to ensure the normal operation unit
the best recommendations for future oil room building following options: minimize the number of oil engine room doors and windows, to avoid leakage of oil machine noise; try to increase the oil from the engine room air intake from the oil-based, extending from the muffler, the best construction air intake chamber; estuary increase in oil-exhaust expansion chamber and try to extend the oil expansion chamber exhaust from the engine room, the room in addition to the five wall surface can be used for acoustic treatment, the use of perforated plate according to the spectral characteristics of the resonant generator sets absorbing structure.
noise generator includes a mechanical noise caused by electromagnetic noise pulsating magnetic field between the stator and the rotor, and the resulting rolling bearing rotation
noise control measures
ensuring the diesel generator ventilation should not reduce the output power of the premise, the use of sound-absorbing material efficiency and noise reduction silencer means air intake and exhaust passages and exhaust systems for noise reduction, so as to meet the national standard noise emission 85db (a
⒈ reduce exhaust noise. exhaust noise is the main noise source unit, which is characterized by high noise levels, exhaust speed, difficult to control. using a special type of impedance composite muffler, exhaust noise will generally reduce 40-60 db (a).
⒉ reduce axial fan noise. when reducing the cooling fan noise generators, we must consider two issues, namely, the exhaust passage allowed pressure loss. second, the amount of noise reduction requirements. in response to these points, the choice of resistance chip muffler
inlets should generator sets, air vents located on the same straight line. inlets should be accompanied by resistive chip muffler, inlet pressure loss is also due within the permissible range, you can make out of the engine room air volume of natural balance, ventilation effect is obvious.
good sound insulation indoor air exchange, room, closed water-cooled generators will shut down the timing can not be convection air room, the room temperature also can not be down, can be low-noise axial fan, matched resistive chip muffler
plus generator cooling system is to be able to increase the output power of the generator in the case of control of the generator volume. otherwise, thanks to natural cooling, very big conductor cross-section of the inevitable choice in order to ensure that the insulation is not damaged.
generators cooling: empty and cold air cooled, water cooled double. water - hydrogen is now more common cooling large units, water-cooled, fan
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