Principle regulator voltage regulator

The working principle of the alternator we know, the three-phase winding of the alternator phase electromotive force generated by RMS Eφ == CeФn (V) where Ce is the generator of the structure constant, n is the rotor speed, Ф poles of the rotor flux, ie  electri cenergy meter  induced  circuit breakers  force generated by the rotor speed and flux is proportional to the magnetic pole. When the speed increases, Eφ increases, the output voltage UB rise, when the speed increases to a certain value (no-load speed above), the output voltage reaches the limit, in order to make the generator output voltage UB is no longer with the with the rise speed, can only be achieved by reducing the magnetic flux Ф. And magnetic flux Ф proportional to the excitation  Electric energy meter , reducing the magnetic flux is reduced Ф excitation current If. So, alternator regulator working principle is: When the alternator speed increases, the regulator by reducing the generator excitation current If to reduce the flux Ф, the generator output voltage UB remains unchanged .
   Contact type voltage regulator through a contact opening and closing, on and off the field circuit, the size of the field current If is changed; transistor regulator IC regulator such as the use of the power transistor on and off, on and off open magnetic circuit, to change the size of the field current If.