Why does the automobile alternator have to be equipped with a voltage regulator?

Not only does the automobile alternator need a voltage regulator, but all engines need it. First clarify the three uses of voltage regulator. The output voltage of the generator needs a rated value, including 220V, 380V, 660V, etc., and the output voltage is determined by the excitation current. Different voltage values require different excitation currents, so the current sent to the excitation winding is determined by the voltage regulator. The main task of the regulator is to always control the excitation current to maintain a constant range. Secondly, after the generator is loaded, the output voltage will drop (voltage drop). When the load power is large, the voltage drop is large, on the contrary, the voltage drop is small. The compensation current needs to be corrected continuously, and this dynamic management is also completed by the voltage regulator. Another is the gain management of the variation value of excitation current. To put it simply, it is to control the multiple of excitation current increment and decrement at an appropriate level, just like the slope of a straight line. The function of the above regulator is realized through the sensor of the external circuit, the calculation in the circuit and the preset of the potentiometer. The purpose of generator operation is to output voltage and current to drive electrical equipment, and voltage stability is an important index to determine the operation quality of generator. We can think of the importance of excitation regulator in generator.