A rectifier is an electrical device that converts AC (alternating current) into DC (direct current). The current flows in only one direction hence the process is called rectification. Rectifiers consist of P-N junction diodes that straighten the direction of the current, meaning the current flows in only one direction. Rectifiers can be classified into half-wave and full-wave. It is found in components of DC motor supplies, power appliances, transformers, soldering irons, radios, detection of amplitude modulated signals, gas heating systems, and power supplies of radio, TV sets, and computers. In this article, we discuss the 10 uses of rectifiers.
Uses of rectifiers
Electric welding
Arc welding is a technique of welding that uses an electric arc to generate heat to melt and jin metal surfaces. Direct current gives better control in arc welding. The AC power has to be first converted to DC(direct current) for the DC arc. This is done using a rectifier on welding machines. There are two types: modern silicon rectifiers and selenium rectifiers.
Power appliances:
A power rectifier circuit is used in power appliances to convert alternating current into direct current. Examples of electric appliances include a Water Heater, Washer, and Dryer, Lights, refrigerator, electric Oven, dishwasher, etc.
Used with transformers:
Rectifier Transformers are used to convert a three-phase alternating current power supply to a DC power supply. Three-phase AC will ensure a smooth DC supply. Such transformers are used where is the varied line and load conditions.
Diodes along with a capacitor are used in a rectifier circuit along with a transformer. The below image shows a rectifier circuit used alongside a transformer. A transformer is used to transfer electric energy from one alternating-current circuit to another by reducing(stepping down) or increasing(stepping up) voltage.
Used while soldering:
To protect the soldering iron from overheating, it is connected to a diode(half-wave rectifier) to allow current in only one-half cycle, thereby reducing the power input to the heating element.
Mosquito repellent:
Rectifiers are used in mosquito repellent to disperse lead fumes.
In radio:
Rectifiers are used in power supplies of radio. A half-wave rectifier as a radio detector is used because the output consists of an audio signal. Long-back radio receivers were also used as rectifiers.
Used for detection of amplitude-modulated signal:
Detection is the process of extracting the original signal from the modulated one. A signal may be amplified before detection. A half-wave rectifier is used in the detection process. You can look at the diagram here to understand it more clearly.
In gas heating system:
Here a flame acts as a rectifier. Flame rectification is used to detect the presence of flames. The rectification effect of a flame helps us to easily detect it by comparing it with a resistive leakage path.
For the power supply of radio, television, and computer equipmentÂ
Rectifier circuits convert AC to DC and allow current to flow in one direction only. The output from the rectifier is then smoothed by using a filter circuit, which may consist of a capacitor or resistors). Sometimes, a voltage regulator might also be used to produce a steady voltage supply.
Voltage multipliers
Voltage multipliers use a rectifier circuit. They convert AC electrical power from a lower voltage to a higher DC voltage.
