Diode rectifier circuit - prevent overcurrent damage to a diode (Shorebrook PE Exam Question 46)

[akyip]

Hi guys,

Regarding preventing overcurrent damage to a diode, I understand the reasoning behind using a 2nd diode in parallel (to divide the current).

But is there a reason why adding resistors to the diode branch is not an appropriate solution to reducing current? Is because of resistor I^2 * R losses? The solution in Shorebrook PE Power Exam Question 46 does not elaborate on this.

Thanks!

 

[Orchid PE]

He's assuming the current is a constant current source. Therefore, a resistor would only affect the voltage drop, it would not reduce the current through the diode.