Differential Transformer

A differential transformer is a type of transducer used to measure displacement or linear movement by utilizing the principle of mutual induction. It consists of a primary coil, a secondary coil, and a movable iron core placed between the two coils.

Working Principle

When an AC voltage is applied to the primary coil, an electromagnetic field is generated which induces a voltage in the secondary coil. The magnitude of this induced voltage depends on the position of the iron core within the coils. As the iron core moves, the magnetic flux linking the secondary coil changes, causing a change in the induced voltage. This change in voltage is proportional to the displacement of the iron core.

Types of Differential Transformer

There are two types of differential transformers:

1. Variable Inductance Transducer: In this type of differential transformer, the position of the iron core changes the mutual inductance between the primary and secondary coils, causing a change in the output voltage. This change in voltage is proportional to the displacement of the iron core.

2. Constant Inductance Transducer: In this type of differential transformer, the mutual inductance between the primary and secondary coils remains constant. The position of the iron core changes the self-inductance of the secondary coil, causing a change in the output voltage. This change in voltage is proportional to the displacement of the iron core.

Applications

Differential transformers are widely used in various industries for measuring linear displacement or movement. Some of the common applications are:

1. Machine tool position control
2. Robotics
3. Aircraft and missile guidance systems
4. Industrial automation
5. Automotive testing
6. Vibration measurement

Conclusion

Differential transformers are highly accurate and reliable transducers for measuring linear displacement or movement. They can be used in a wide range of applications where precise measurement is required.