Active Transducer:

A transducer is a device that converts one form of energy into another. An active transducer is a type of transducer that requires an external source of energy to operate. It converts the physical quantity into an electrical signal. The output of an active transducer is a high-level signal, which is suitable for processing by electronic circuits.

Piezoelectric Transducer:

Piezoelectric transducers are a type of active transducer that convert mechanical energy into electrical energy. They are made of piezoelectric materials such as quartz crystal, barium titanate, or lead zirconate titanate. Piezoelectric materials generate an electric charge when they are subjected to mechanical stress.

Working Principle:

When a piezoelectric transducer is subjected to mechanical stress, it generates an electric charge. The magnitude of the charge is proportional to the applied stress. The electrical charge generated by the transducer is very small, and it needs to be amplified by an electronic circuit.

Applications:

Piezoelectric transducers are used in a wide range of applications such as:

- Ultrasonic sensors
- Acoustic emission testing
- Vibration measurement
- Pressure measurement
- Accelerometers

Advantages:

- High sensitivity
- Wide frequency range
- Low power consumption
- Compact size

Disadvantages:

- Limited dynamic range
- Non-linear response
- Temperature sensitivity

Conclusion:

Piezoelectric transducers are a type of active transducer that are widely used in various applications. They convert mechanical energy into electrical energy and require an external source of energy to operate. They have high sensitivity, a wide frequency range, and low power consumption.