GENERATOR

GENERATOR

One of the major parts of the power system is hydroelectric station. The hydroelectric station can be powered with a power generator gas, hydroelectric, diesel and so forth. The main staple in the procurement of electric power system is part of the generator or in this case the generator. If a generating system is compromised, then the entire power system will stop operation.

Cause of disturbances in power systems consist of three parts:

1. Interference from outside the generator, which is connected to disturbances in the system generator.

2. Disruption in the generator.

3. Disorders of the engine driving the generator.

Of the three types of disorders above, if one generator that works in parallel to crash, most likely generator in operation no longer able to bear the whole burden. Therefore the calculation of the amount of load required to be decided by a sudden order to obtain the stability of the system.

 The main components of the generator

 

(1) Engines

Machine is a source of mechanical energy input to the generator. Engine size is directly proportional to the maximum power output the generator can supply. There are several factors that you need to keep in mind when assessing your generator engine. The engine manufacturer should be consulted to obtain full engine operation specifications and maintenance schedules.

(2) Alternator

Alternator, also known as 'genhead', is part of the generator that produces the electrical output of the mechanical input given by the machine. This assembly contains parts still and moving encased in housing. Components work together to cause relative movement between the magnetic and electric fields, which in turn produces electricity.

·         Stator, It is a stationary component. It contains a set of electrical conductors wound in coils over an iron core.

·         Rotor / Armature, It is a moving part that generates a rotating magnetic field on one of the three following ways:

1.       Based on the induction. These are known as brushless alternators and are usually used in large generators.

2.       With a permanent magnet - It is common in small alternator units.

3.       By using an exciter - exciter is a small source of direct current (DC) that energizes the rotor through the slip ring assembly and brushes do. Rotor generates a magnetic field that moves around the stator, which induces a voltage difference between the stator windings. It produces alternating current (AC) output of the generator.

(3) Fuel System
Fuel tank usually has sufficient capacity to keep the generator operational for 6 to 8 hours on average. In the case of small generator units, the fuel tank is part of the basic skid mounted above the generator or generator frame.

(4) Voltage Regulator: Conversion of AC to DC Voltage Current - voltage regulator takes a fraction of generator output AC voltage and converts it into DC current. The DC voltage regulator then feeds current to a set of secondary windings in the stator, which is known as the exciter coil.

(5) Cooling & Exhaust Systems

a.       Cooling Systems

Continuous use generator causes a variety of components to get heated up. It's important to have a cooling and ventilation system to draw heat generated in the process.

Raw water / fresh is sometimes used as a coolant for the generator, but this is mostly limited to specific situations such as small generators in the city or the application of a very large unit above 2250 kW and above. Hydrogen is sometimes used as a coolant for the stator winding of the generator unit because it is more efficient at absorbing heat than other coolers. Hydrogen removes heat from the generator and transfer through the heat exchanger into the secondary cooling circuit which contains de-mineralized water as a coolant. This is why very large and small generators often have large cooling towers next to them.

b.      Exhaust System

Exhaust fumes emitted by the exhaust from the generator just like any diesel or engine gasonline and contain highly toxic chemicals that need to be managed properly. Therefore, it is important to install adequate drainage system to dispose of waste gases.

(6) Lubricating System

Since the generator consists of moving parts in the engine, requires lubrication to ensure smooth operation and durability for a long period of time. Generator engines are lubricated by oil stored in the pump. You should check the oil level every 8 hours of operation lubricating generator. You also have to check the leakage of lubricants and lubricating oil change every 500 hours of operation of the generator.

 (7) Battery Charger

Beginning of the function generator is operated with battery. Battery charger makes battery power charged with supplying the proper voltage 'float'. If the float voltage is very low, the battery will remain undercharged. If the float voltage is very high, it will shorten the battery life. Battery chargers are usually made of stainless steel to prevent corrosion.

 (8) Control Panel

It is the user interface of the generator and set some requirements for electrical outlets and controls. The following article gives more details about the generator control panel. Different manufacturers have varied features offered in their unit control panel.

(9) Primary Framework / Frame

All generators, portable or stationary, was adjusted housing that provides structural support base. Frame also allows for the generated shall be grounded / grounding for safety.

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