An automatic voltage regulator (AVR) is a electronic device for automatically maintaining generator output terminal voltage at a set value under varying load and operating temperature. It controls output by sensing the voltage output at a power-generating coil and comparing it to a stable reference. The error signal is then used to adjust an average value of the field current.
Most cheap portable generators have fixed excitation. In such machines, when an alternator is loaded, its terminal voltage drops due to its internal impedance. This impedance is formed of leakage reactance, armature reactance and armature resistance. The Vout also depends on the power factor of the load. That’s why to maintain Vout within tighter limits, more expensive models use an AVR.
N:B All AVRs help regulating the output in a steady state operation, but are generally slow to respond to fast transient loads.
Q: What will happen if we removed the AVR from the generator circuit?
A: If you remove an AVR from Generator it means that we removed the heart of generation of the alternator, It will not receive voltage to excite to generate voltage. Automatic Voltage Regulator, acts as a capacitor storing power, any spikes in power is held and stored by the AVR circuit capacitors thus delivering the set voltage range which should have been done with pre-delivery inspection. Removing the AVR in the total generator circuit will give you fluctuations in output power. It is very important to get your engine speed to correct RPM before adjustment of AVR is done. If engine RPM is out of range. You stand a huge chance of blowing your AVR.
Removing the AVR in the total generating set circuit will give fluctuations in the output power.
Remark: It is very important to get your engine speed to correct RPM before adjustment of AVR is done. If engine RPM is out of range. You stand a huge chance of blowing your AVR.