A voltage stabilizer is a power appliance used to feed constant voltage current to electrical appliances, protecting them from damage because of voltage fluctuations and erratic power supply. Basically, it works on the same principle as that of a transformer, where in actuality the input current is linked to primary winding and output current is obtained from secondary winding.
If you have a sudden and unexpected drop in incoming voltage, it activates electromagnetic relays which add to more current to the secondary winding hence increasing or compensating for the drop in voltage.If there is a boost in the incoming voltage, the opposite happens, and, thus, the voltage in the output side becomes constant.
How do voltage stabilizers actually work?
In a voltage stabilizer, voltage correction from over and under voltage condition is carried out by two vital operations, called boost and buck operations. These operations can either be done manually or automatically through modern electronic circuit based systems. When there is a situation of under voltage then, boost operation boosts the voltage to the required levels whereas buck operation will reduce the voltage level when the situation is opposite.