A rectifier, also called AC/DC converter or Graetz bridge, is a converter intended to supply a load which needs to be supplied by a voltage and a current that are both as continuous as possible, from an AC voltage source. .
The power supply is, most of the time, a voltage generator.
Uncontrolled rectifiers, mainly made from diodes, are used when the output voltage does not need to be adjusted.
Controlled rectifiers whose output voltage can be variable comprise thyristors or sets of diodes and thyristors.
Because of their high mass power, these rectifiers are always used at high power and when it is necessary to regulate or vary the electrical quantities at the output.
In low and medium power, thyristor controlled rectifiers are becoming obsolete and are advantageously replaced by the “cascading” of a controlled or uncontrolled rectifier and a DC-DC converter.
At low powers, the control of a field effect transistor or an IGBT is simpler than that of a thyristor, on the other hand, the operating frequencies of the choppers, which today are in the domain of 200 kHz, make it possible to considerably reduce the size of the filtering components (inductors and capacitors).
Finally, there are sinusoidal absorption rectifiers built using diodes, Ballast MOSFET transistors or IGBTs which are used to improve the waveform of the alternating current consumed on the network side.
The single diode rectifier is a very common device but it is used more as a power variation device than as a rectifier: for heating applications, it allows, for a very low cost, to halve the power consumed by the load . Almost all hair dryers have two heating powers. the switch which controls the tilting is placed in parallel with a diode. When full power is desired, the switch short-circuits the diode and the resistor is supplied directly by the mains. For half power operation, the switch is open and the diode is in series with the load.
Half-wave controlled rectification, like single-phase controlled rectification, has no industrial application.
A rectifier, also called AC/DC converter or Graetz bridge, is a converter intended to supply a load which needs to be supplied by a voltage and a current that are both as continuous as possible, from an AC voltage source. .
The power supply is, most of the time, a voltage generator.
Uncontrolled rectifiers, mainly made from diodes, are used when the output voltage does not need to be adjusted.
Controlled rectifiers whose output voltage can be variable comprise thyristors or sets of diodes and thyristors.
Because of their high mass power, these rectifiers are always used at high power and when it is necessary to regulate or vary the electrical quantities at the output.
In low and medium power, thyristor controlled rectifiers are becoming obsolete and are advantageously replaced by the “cascading” of a controlled or uncontrolled rectifier and a DC-DC converter.
At low powers, the control of a field effect transistor or an IGBT is simpler than that of a thyristor, on the other hand, the operating frequencies of the choppers, which today are in the domain of 200 kHz, make it possible to considerably reduce the size of the filtering components (inductors and capacitors).
Finally, there are sinusoidal absorption rectifiers built using diodes, Ballast MOSFET transistors or IGBTs which are used to improve the waveform of the alternating current consumed on the network side.
The single diode rectifier is a very common device but it is used more as a power variation device than as a rectifier: for heating applications, it allows, for a very low cost, to halve the power consumed by the load . Almost all hair dryers have two heating powers. the switch which controls the tilting is placed in parallel with a diode. When full power is desired, the switch short-circuits the diode and the resistor is supplied directly by the mains. For half power operation, the switch is open and the diode is in series with the load.
Half-wave controlled rectification, like single-phase controlled rectification, has no industrial application.
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