Electrical :Advantages of constant voltage transformer?

>>The CVT is simply a magnetic transformer of a special construction that has a capacitor connected across the secondary winding of the transformer.

 

>>In an ordinary transformer, the primary and secondary windings are wound near each other so that whenever there is a change of voltage across the primary there is a corresponding change in the secondary voltage depending upon the ratio of the turns on the two windings. However, in a CVT the primary and secondary windings are wound separately from each other. 

>>The CVT provides several benefits such as:Superior Voltage Regulation - Even with considerable variations in input voltage of up to ±40% of nominal, the output voltage regulation will still be about 1% to 4%.Sag Mitigation: If properly sized, a CVT can regulate its output voltage during a voltage sag to 60% for any duration. However, CVTs are not effective during momentary voltage interruptions or extremely deep voltage sags (generally below fifty percent of nominal). 

>>CVTs are often favored over other sagmitigation devices because they are relatively maintenance-free, with no batteries to replace or moving parts to maintain.Ride-through capability: As mentioned, CVTs also have the special characteristic of being able to store energy for up to 1/2 cycle because of its "tank circuit" design. 

>>Combining CVT with an inverter and static transfer switch in a UPS application, this characteristic provides a ride-through capability allowing a completely uninterrupted transfer to an alternate source. This application is very useful in the event of an overload, fault or even in the event of a total loss of the inverter, thereby maintaining power to the load. 

>>Current Limiter: In some specialized applications, these devices can be designed to supply a constant current output, rather than constant voltage. Current limiting is an inherent benefit of ferroresonant transformers. In cases where the load current exceeds 150% of rated current of the ferro or CVT, the unit is pulled out of the saturation region, the output voltage collapses to a very small value and the current is thereby limited. However, in applications with high inrush current this characteristic becomes a disadvantage.Isolation from Surges, Harmonics and Noise due to the CVT’s tank circuit design.CVTs are durable and robust that some manufacturers offer warranties in excess of 10 years.