Application And Composition Of Diesel Power Generator

1. Purpose of diesel generator set.

Diesel generator set is an important part of communication equipment. Its main requirements are that it can start at any time, supply power in time, operate safely and reliably, ensure the voltage and frequency of power supply and meet the requirements of electrical equipment.

Composition: engine, three-phase AC (brushless synchronous) generator, control panel and auxiliary devices.

Engine: a rigid whole composed of diesel engine, cooling water tank, coupling, fuel injector, muffler and common base.

Synchronous generator: when the main magnetic field is driven and rotated by the engine, it pulls the armature to rotate, just as there is mutual attraction between two magnets. In other words, the rotor of the generator drives the armature magnetic field to rotate at the same speed, and the two maintain synchronization, so it is called synchronous generator. The speed of the armature magnetic field is called synchronous speed.

Conversion form of energy: chemical energy - thermal energy - mechanical energy - electrical energy.

2. Structure of engine.

A.Engine body

Cylinder block, the cylinder cover, cylinder liner, oil pan.

The conversion of thermal energy and mechanical energy in internal combustion engine is completed through four processes: intake, compression, work and exhaust. Each time the machine performs such a process is called a work cycle.

B.Connecting rod crank mechanism

Piston set: piston, piston ring, piston pin, Connecting rod group.

Crank flywheel set: crankshaft, crankshaft gear, bearing bush, starting gear, flywheel and pulley.

C.Valve train.

It is the control mechanism to realize the intake process and exhaust process of the engine. 

The arrangement forms include overhead valve and side valve.

Valve assembly: valve, valve guide, valve spring, spring seat, locking device and other parts.

Intake and exhaust system of engine

Intake and exhaust manifolds, air filters, intake and exhaust ducts and exhaust silencers in cylinder heads or cylinder blocks. 

Turbocharger: increase the air density per unit volume, increase the average effective pressure and power, and reduce fuel consumption. 

Low pressurization: < 1.7 (indicating the pressure ratio between inlet and outlet): medium pressurization: = 1.7-2.5 high pressurization > 2.5.

Use intercooling to reduce the temperature of the gas.

3.Oil supply system

Function: according to the working requirements, spray the well atomized diesel oil into the cylinder according to a certain injection law at fixed time, fixed quantity and pressure, and make it burn quickly and well with air.

Composition: oil tank, fuel pump, diesel coarse and fine filter, fuel injection pump, fuel injector, combustion chamber and oil pipe.

Engine speed adjustment is divided into mechanical speed regulation and electronic speed regulation. Mechanical speed regulation is divided into centrifugal type, pneumatic type and hydraulic type.

4.Lubrication system

Function: lubricate all friction surfaces, reduce wear, clean and cool, improve sealing performance, and prevent rust for all moving parts.

Composition: oil pump, oil pan, oil pipeline, oil filter, oil cooler, protection device and indication system.

An important indicator of lubrication system: oil pressure.

Oil model: 15W40CD

5.Cooling system

Too high or too low engine operating temperature will reduce its power and economy. The function of the cooling system is to keep the engine working at the most appropriate temperature, so as to obtain good economy, power and durability. According to the cooling mode, there are air cooling and water cooling.

Air cooled cooling has the advantages of simple structure, light weight and convenient use and maintenance, but the cooling effect is poor, power consumption and noise are large. At present, it is mostly used in small internal combustion engines and is suitable for plateau deserts and water shortage areas.

There are two types of water cooling: open and closed. According to different cooling cycle methods, closed cooling can be divided into evaporation, natural circulation and forced circulation. Most engines use a forced circulating water cooling system.

Composition: water pump, cooling water tank, fan, thermostat, cooling pipe and cylinder head, cooling water jacket and water temperature gauge formed inside cylinder block crankcase, etc.

6. Start-up system

The whole process of the engine from standstill to movement is called starting. A series of devices that complete the start-up are called the starting system of the engine. 

Starting method: manual starting, motor starting and compressed air starting. Fenglian unit is started by motor.

Composition: battery, charger, starting motor and wiring.