In modern life, electric power has become an indispensable part of existence. There are many ways to generate electricity. But why should we choose diesel generator set? Let's learn about the diesel generator set together!

Diesel generator set

Diesel generator set is a kind of power generation equipment with diesel as the main fuel. The diesel engine is used as the driving force to drive the generator (i.e. electric ball) to generate electricity and convert kinetic energy into electrical energy and heat energy. The whole set of diesel generator set is mainly divided into three parts:

1. Diesel engine.

2. Generator (i.e. electric ball).

Controller.

 

How does a diesel generator set work?

The diesel engine drives the generator and converts the energy of diesel into electric energy.

In the cylinder of diesel engine, the clean air filtered by the air filter is fully mixed with the high-pressure atomized diesel from the fuel injection nozzle. Under the upward extrusion of the piston, the volume is reduced and the temperature rises rapidly, reaching the ignition point of diesel oil. When the diesel oil is ignited, the mixed gas burns violently, and the volume expands rapidly, pushing the piston downward, which is called "work". Each cylinder works in a certain order, and the thrust acting on the piston turns into a force to push the crankshaft to rotate through the connecting rod, thus driving the crankshaft to rotate.

If the brushless synchronous alternator is installed in the same axis with the crankshaft of the diesel engine, the rotation of the diesel engine can be used to drive the rotor of the generator. Using the "electromagnetic induction" principle, the generator will output the induced electromotive force, and the current can be generated through the closed load circuit.

Diesel generator set is a type of AC power supply equipment of self provided power station. It is a small independent power generation equipment. It uses internal combustion engine as power and drives synchronous alternator to generate electricity.

Modern diesel generator set consists of diesel engine, three-phase AC brushless synchronous generator, control box (panel), cooling water tank, coupling, fuel tank, muffler and common base. The flywheel housing of diesel engine and the front cover of generator are directly connected by shoulder positioning in axial direction, and cylindrical elastic coupling is used to drive the rotation of generator directly by flywheel. The connection mode is fixed by screws to make the two connected into a steel body, which ensures the concentricity of diesel engine crankshaft and generator rotor within the specified range.

In order to reduce the vibration of the unit, shock absorbers or rubber damping pads are usually installed at the joint of the main components such as diesel engine, generator, water tank and electrical control box with the common base.

Installation requirements of diesel generator set:

 

1. A space of no less than 1 m shall be reserved around the diesel generator set, and a ventilation window shall be reserved at the water tank end according to the size of the water tank core. This requirement is the minimum size of the unit room, which can be increased by users according to their needs.

2. The foundation of diesel generator set shall be built on hard soil ground. After tamping, 200 mm thick concrete ground shall be made, and the ground shall be flat.

3. When building the machine room, the user should embed the I-beam for lifting on the roof above the unit (≤ 250KW is not required) for future maintenance.

4. The machine room should be well ventilated and the ground should be smooth and non slip.

5. The inner diameter of the exhaust pipe of the unit shall not be less than the diameter of the exhaust port of the diesel engine, the number of bends shall not be more than 3, and the angle of the elbow shall be greater than 90 degrees. The exhaust pipe shall be supported or hoisted to ensure that the muffler and supercharger of the unit will not be stressed.

6. Fire fighting tools such as fire extinguisher shall be provided in the machine room.

 

Advantages of diesel generator set

 

1. The capacity of single machine is various and the equipment is convenient

The single unit capacity of diesel generator sets ranges from several thousand watts to several tens of thousands of kilowatts. According to its use and load conditions, the range of optional capacity is large, which has the advantage of being applicable to various capacity electric loads. When the diesel generator set is accepted as emergency and standby power supply, one or more units can be accepted, and the installed capacity is sensitive according to the actual demand.

2. The unit is light in power and sensitive in installation

The matching equipment of diesel generator set is relatively simple, with less auxiliary equipment, small volume and light weight. Taking high-speed diesel engine as an example, the average value is 820Kg / kW, while the steam power plant is more than 4 times larger than the target of diesel engine. Due to the characteristics of diesel generator set, it is sensitive and convenient to move.

The diesel generator set used as the main power supply of independent power supply mostly adopts the method of independent equipment, while the standby or emergency diesel generator set is commonly used with the transformer and distribution equipment. As the diesel generator set is not normally operated in parallel with the municipal power grid, and the unit does not need full water [the cooling water consumption of diesel engine is 3482l / (kW. H), which is only 1 / 10 of that of steam turbine generator set], and occupies a small area, so the installation of the unit is relatively sensitive.

3. High thermal compliance and low fuel consumption

The effective thermal compliance of diesel engine is 30% 46%, that of HP steam turbine is 20% 40%, and that of gas turbine is 20% /30%. It can be seen that the effective thermal compliance of diesel engine is relatively high, so its fuel consumption is low.

4. It can start quickly and reach full power

It takes only a few seconds to start the diesel engine, and it can carry full load within 1 min under emergency mode, and it can reach full load in 510 min under normal working mode, and 34h is required for steam power plant from starting to full load. Diesel engine shutdown process is also very short, can start and stop frequently. Therefore, diesel generator set is suitable for emergency or standby power supply.

5. Simple operation and convenient maintenance

The diesel generator set can be started and maintained by the ordinary staff who have read the instructions carefully. If there is any fault in the unit, it can be repaired by the On-the-Machine method, which requires less repair staff and is convenient for maintenance.

6. The integrated cost of power station establishment and power generation is low

Compared with the water turbine units which need to build dams, the steam turbine units need to be euipped with steam boilers and large fuel preparation and water treatment systems, the diesel power station has the advantages of small floor area, fast establishment speed and low investment cost.

Compared with renewable power generation such as hydropower, wind power and solar energy, as well as nuclear power and thermal power generation, diesel power station has the lowest integration with power generation.

Why do users generally prefer diesel generators to gasoline generators?

 

Everyone has a certain and certain way that everyone prefers. In modern life, more and more users use diesel generator set as standby power supply. Although there are various ways of generating electricity, people still choose diesel generator.

The efficiency of gasoline generator is low, and the power generated by the same quality gasoline engine is less than that of diesel generator with the same quality.

The price of gasoline is high, and the price of gasoline of the same volume is higher than that of diesel oil. The density of gasoline is not the same as that of diesel.

Application and general requirements of diesel generator set

 

Diesel generator set is a kind of small power generation equipment, which uses diesel oil as fuel and diesel engine as prime mover to drive generator to generate electricity. The whole unit is generally composed of diesel engine, generator, control tank, fuel tank, storage battery for starting and control, protection device, emergency cabinet and other components. The whole can be fixed on the foundation for positioning, and can also be installed on the trailer for mobile use. Diesel generator set is a kind of non continuous operation power generation equipment, if the continuous operation for more than 12 hours, its output power will be about 90% lower than the rated power. Although the power of diesel generator set is low, due to its small size, flexibility, portability, complete set, easy operation and maintenance, it is widely used in mines, railways, field construction sites, road traffic maintenance, as well as factories, enterprises, hospitals and other departments as a backup power source or temporary power supply.

Several factors should be considered in generator set selection

 

It mainly includes the mechanical and electrical performance, the purpose of the unit, the load capacity and variation range, the use environmental conditions of the unit (including altitude, climate conditions, noise), automation functions, etc. Because the diesel generator set can be used in common use, standby and emergency, the requirements of diesel generator set for different purposes are different.

When to change the oil of diesel generator

 

Generally speaking, the new unit will work 50 hours after the first operation and 50 hours after the intermediate repair or overhaul. The oil change cycle is generally carried out at the same time as the oil filter (filter element), and the general oil change cycle is 250 hours or one month. With type 2 oil, the oil can be extended to work for 400 hours before changing, but the oil filter (filter element) must be replaced. If you want to accurately determine the replacement time of diesel generator, you must know some of the judgment methods

1. Two glass tubes with a diameter of 0.5cm and a length of 20cm are used to fill 19cm of new oil and used oil respectively. After sealing, the two tubes are inverted at the same time, and the rising time of bubbles is recorded. If the difference between the two is more than 20%, it means that the viscosity of used oil drops too much and should be replaced.

2. Compare the new engine oil and the used engine oil on the white filter paper. If there are more black spots in the used oil drops, it indicates that the oil has not deteriorated and should not be replaced; if the oil is dark brown, it is deteriorated and should be replaced.

Another thing to note is that different manufacturers and different powers of diesel generator oil is not the same, so when you buy a diesel generator, you must ask the manufacturer what kind of oil is used for the unit.

As top China generator set supplier, we supply ac alternator, mobile diesel generator, 3 phase diesel generator and other generator sets. If you have any questions about the generator set, please contact us!