The advantages and disadvantages of diesel generatorsFeatures of diesel generators:
(1) more capacity of single machine. International units from a few kilowatts to tens of thousands of kilowatts, the largest domestic units of several thousand kilowatts
(2) compact structure and flexible installation location of supporting equipment (water cooling only takes 1/10 of the steam turbine of 34-82l /KW·H)
(3) high thermal efficiency, low fuel consumption (thermal efficiency: 30-46%)
(4) it only takes a few seconds to start quickly and reach full power quickly. The full load (normal 5-30min) stopping process with expired within 1 minute of emergency is short and can be started and stopped frequently.
(5) simple maintenance operation, few people, easy maintenance during standby
(6) the construction and comprehensive cost of diesel generator sets are the lowest
Advantages of diesel generators:
(1) when fuel economy, high thermal efficiency and working conditions change, the fuel consumption rate curve changes relatively flat, and it is also economical under low load
(2) reliable and durable. Because there is no ignition system, the failure is low
(3) wide range of use
(4) low harmful emissions
(5) good fire safety
The automatic voltage regulation of the generator includes: thyristor, phase compound excitation, TD1 type carbon resistance automatic voltage regulation, some of which adopt high power tube.
Disadvantages of diesel generators:
The wrong operation of diesel generator will seriously affect the service life of diesel generator set. Now let's learn about the wrong operation mode of diesel generator set in daily operation.
(1) wrong operation of diesel generator 1: diesel engine runs when the oil is insufficient
At this point, due to insufficient oil supply, the surface of each friction pair will be insufficient oil supply, resulting in abnormal wear or burn. For this reason, diesel generators should ensure sufficient oil before starting and during the operation of diesel engines, so as to prevent the failure of drawing cylinder and burning tile caused by oil shortage.
(2) wrong operation of diesel generator ii: stop immediately with load or after sudden unloading of load
Diesel generator cooling system of the water cycle to stop, after cooling capacity sharply reduce, the heat loss of cooling, easy to cause the cylinder head, cylinder liner, cylinder block, such as overheated parts, cracks, or stuck within the cylinder piston. On the other hand, when the diesel generator is stopped without idle speed cooling, the friction surface will not contain enough oil. When the diesel engine is started again, it will be aggravated by poor lubrication and wear. Therefore, before the diesel generator is put out, the load should be removed and the rotating speed and no-load operation should be reduced gradually for several minutes.
(3) wrong operation of diesel generator 3: run with load without heating after cold start
Diesel generator cooling machine starts, because of heavy oil viscosity, liquidity is poor, is that shortage of lubricating oil in oil pump to machine friction surface for lack of oil, poor lubrication cause rapid wear, such as cylinder, tile burning even failure. Diesel engine cooling after start-up, therefore, should be idle running to heat up, for the oil loading again when the temperature is above 40 ℃; The machine should start with low speed gear and drive a length of miles in each gear step by step until the oil temperature is normal and the oil supply is sufficient.
(4) wrong operation of diesel generator 4: after the diesel engine starts cold, the throttle is slammed sharply
If the accelerator is slammed sharply, the speed of diesel generator rises sharply, which will cause some friction surfaces on the machine to be severely worn due to dry friction. In addition, the acceptance force of piston, connecting rod and crankshaft changes greatly when the throttle is honked, causing severe impact and easy to damage the machine parts.
(5) wrong operation of diesel generators v: operate in case of insufficient cooling water or excessive cooling water and oil temperature
The insufficient cooling water of diesel generator will reduce its cooling effect. The oil temperature of cooling water and oil is too high, which will also cause the diesel engine to overheat. The diesel generator cylinder head, cylinder liner, piston components and valve such as the main heat load is big, sharp decline in its mechanical properties such as strength, toughness, increase the deformation of parts, reduce the fit clearance between the parts, accelerate parts wear and tear, serious when still can produce crack, parts stuck fault. Diesel generator overheating will also aggravate the diesel engine combustion process, make the injector work disorder, bad atomization, increase carbon accumulation.