The definition and application of generator.

Electric Generator  is to turn mechanical energy into electrical energy motor, usually driven by steam turbine, turbine, or internal combustion engine Generator points of two kinds of dc generators and alternator, which in turn can be divided into synchronous Generator and induction Generator.Modern power plant is the most commonly used in synchronous generator (i.e., the speed of the generator rotor and the stator magnetic field rotation speed keep synchronous speed).It is composed of dc excitation current, can not only provide active power, also can provide reactive power, can meet the needs of all kinds of load.Not have independent excitation winding induction generator, its structure is simple, easy to operate, but it can't provide reactive power to the load
Therefore, run time asynchronous generator must be with other synchronous generators in parallel, or and a number of capacitor.A commutator dc generator, the structure is complex, expensive, easily out of order, maintenance difficulties, efficiency and alternator.Therefore, since the 1950 s, the dc generator gradually for the ac power by power semiconductor rectifier dc replaced.