What is teaser transformer?

Short Answer:

A teaser transformer is a special type of transformer used in open-delta (V-V) connections or Scott-T connection to provide a balanced three-phase supply from a two-phase source. It works alongside the main transformer to convert two-phase power into three-phase power, commonly used in industrial applications.

The teaser transformer plays a crucial role in ensuring voltage balance and phase shift between the input and output. It is mainly found in railway electrification, power distribution systems, and motor drives, where three-phase power is required but only a two-phase source is available.

Detailed Explanation

Teaser Transformer

A teaser transformer is used in systems where three-phase power needs to be generated from a two-phase supply. It is commonly seen in Scott-T transformers, which convert two-phase power into a balanced three-phase system.

  1. Working Principle

    • A Scott-T connection consists of two transformers:
      • Main transformer: Connected between one phase and neutral.
      • Teaser transformer: Connected between the second phase and a tapping point on the main transformer.
    • The teaser transformer introduces a 90-degree phase shift, ensuring that the three-phase output is properly balanced.

  2. Key Applications

    • Railway Electrification: Used in railway systems where the power supply is single-phase or two-phase but three-phase power is needed for motors.
    • Industrial Loads: Converts two-phase power to run three-phase motors and heavy equipment.
    • Power Distribution: Helps in balancing loads in electrical networks.

  3. Advantages of Using a Teaser Transformer

    • Efficient Three-Phase Generation: Converts two-phase input into a balanced three-phase output.
    • Better Load Sharing: Helps in distributing electrical loads evenly.
    • Cost-Effective Solution: Avoids the need for a separate three-phase power supply in areas where only two-phase power is available.

  4. Difference Between Teaser Transformer and Main Transformer

    • The main transformer carries more load and is connected directly to the supply.
    • The teaser transformer assists in phase shifting and ensures proper voltage balance.
Conclusion

A teaser transformer is an essential component in Scott-T and open-delta transformer systems, enabling the conversion of two-phase power to three-phase power. It helps in maintaining voltage balance and phase shift, making it useful in railway electrification, industrial applications, and power distribution where a three-phase supply is needed but only a two-phase source is available.