Auto-transformer

Autotransformers refer to those transformer where the primary and the secondary winding of the transformer are connected to each other, physically and magnetically. In another words, in an autotransformer, part of the windings is common to both primary and secondary. Autotransformers are used quite extensively in bulk power transmission systems because of its ability to multiply the effective KVA capacity of a transformer. Autotransformers are also used on radial distribution feeder circuits as voltage regulators.

 
Standards
Estel’s autotransformers are designed and tested according to IEC61558/IEC60076-1 standards or as specified by customers.


Features
Features and benefits
- Can be use as either a step-up or step-down transformer
- More efficient and relatively smaller than conventional transformers
- Output voltage can be adjusted as per requirement
- Low requirements of excitation current
- Voltage regulation of autotransformer is much better


Applications:
- Used in both Synchronous motors and induction motors.
- Used in electrical apparatus testing labs since the voltage can be smoothly and continuously varied.
- They find application as boosters in AC feeders to increase the voltage levels.
- Used in HV substation