Servo Voltage Stabilizers
A phase of buck-boost transformer primary is connected to the fixed tap of the autotransformer and another one connects with the moving arm which is controlled by the servo motor. Apart from it, the buck-boost transformer primary of servo stabilizer gets connected in the series of incoming voltage. These stabilizers called servo stabilizer because it uses a servo motor to enable the voltage correction. It is mainly used for high output voltage accuracy. Usually, ±1 % with input voltage changes up to ± 50 %. It is most popular for low high rating appliances used in homes, offices, and industries to provide correct voltage rate for protecting equipment and their desired performance. Demand
These stabilizers can be single-phase, three-phase Oil cooled and Air cooled balanced unit type or three-phase unbalanced. In a single phase servo stabilizer, a motor coupled to the variable transformer to achieve voltage correction. Meanwhile, in three-phase balanced type, a servo motor is coupled with three autotransformers such that stabilized output is provided during fluctuations by adjusting the output of the transformers. Whereas in unbalanced servo stabilizers, there are three independent servo motors coupled with three autotransformers.
If we compare servo stabilizers with relay type stabilizers we can find various advantages of servo voltage stabilizer such as higher correction speed, high precision of stabilized output, capable to withstand inrush currents and most importantly the high reliability. There are many different types of Load/Machines which require servo voltage stabilizer.