Half Wave Rectifier Diagram: Overview, Questions, Preparation

A diode is an electric component that allows the current to pass in a single direction. When the alternating voltage is applied across the diode, the current flows only in that part of the cycle when the diode is forward-biased. This property helps in rectifying alternating voltages. The circuit used for this purpose is called a rectifier. 

• The different applications of the diode include rectifiers, inverters, clampers and parameter amplifiers. 
• In simple terms, rectification is the conversion of alternating current (AC) to direct current (DC).

• A half-wave rectifier is a single PN junction diode connected in series to a load resistor. The diode is placed between the transformer and the load resistor.
• In a half-wave rectifier, the rectification process occurs only during half-periods. Another half cycle is not in use. 

• The diode is connected in series with the secondary of the transformer and the load resistor. The primary of the transformer connects to the AC mains.
• The alternating current provided as input. And it reaches the transformer to supply the desired voltage across terminals A and B.
• When the voltage at A is positive, the diode is forward biased whereby it conducts current.
• When the voltage at A is negative, the diode is negative biased and does not conduct current.
• The reverse saturation of the current is negligible and considered as zero.
• The output voltage developed across the load resistor is not steady dc.

The waveform appears as a pulsating DC waveform because of using a rectifier without a filter. Filters like capacitor filters change the pulsating input into a constant dc output.

The ratio of dc power output to the applied input a.c power is known as rectifier efficiency, denoted by η. The maximum efficiency is 40.6%. 

The half-wave rectifier is the subtopic of the ‘Applications of Junction Diodes as a Rectifier.’ One must be aware of all the formulas because the numerical based questions are more from this topic.

• In half-wave rectification, what is the output frequency if the input frequency is 50 Hz?

For Half-wave rectification, the output frequency is equal to the input frequency. So it is 50 Hz.

• What is the transformer utilisation factor of a half-wave rectifier?

Transformer utilisation factor is the ratio of DC output power to the AC of the secondary winding. The value is 0.287

• What is the peak inverse voltage (PIV) of a half-wave rectifier, if the peak voltage of the circuit is 5V and the diode cut-in voltage is 0.7?

 PIV is the maximum voltage that the diodes resist. Therefore, the PIV is 5V.

Q: What are the advantages of a half-wave rectifier?

Q: What is the ripple factor of the half-wave rectifier?

Q: What are the applications of the half-wave rectifier?

Q: What is the peak inverse voltage of the half-wave rectifier?

Q: How to protect the diode from a reverse breakdown?