Half Wave Controlled Rectifier using SCR (Working with Waveforms )
Half wave controlled Rectifier using SCR
Diode Rectifiers
The rectifiers which convert ac voltage into fixed dc voltage are called as diode rectifiers or uncontrolled rectifiers.
SCR Rectifiers
The rectifiers that uses SCR in place of diodes and in which the output voltage is varied using the firing angle 𝛂 of SCR are called as SCR rectifiers.
They are also called as controlled rectifiers.
Key points :
A conducting SCR can be turned off by natural or line commutation.
These convertors are called as Line Commutated Convertors(LCC) as AC mains voltage is itself used to commutate the these SCRS
These convertors are simple and less expensive and their efficiency is generally higher than 95%.
They can convert ac to variable dc therefore , they are also called as ac to dc convertors.
They are widely used in industries for eg : dc motor speed control.
Delay Angle or Firing Angle 𝛂 :
It is the value of 𝛚t at which SCR or pair of SCRs are turned ON.
It is denoted by 𝛂 and measured w.r.t. zero crossing instant of ac supply voltage .
Half Wave Controlled Rectifiers (HWCR) :
In this rectifier the load power can be controlled by one half cycle of ac supply.
During +ve half cycle of ac input voltage : SCR is turned ON at 𝛚t = 𝛂
During -ve half cycle of ac input voltage : SCR is turned OFF
#HalfWaveControlledRectifiers(HWCR)
#SinglePhaseControlledRectifiers
#ACtoDCConvertors
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