RECTIFIER

[Abayomi]

Please I need help me out. I wanted to build a voltage regulator but I hanged at the rectifier stage, the transformer i used is a 30v 2A but in the schematic it is 30v 1A, I connected a bridge diode to and a filter capacitor to rectify it to DC, the output voltage is 41V. this is strange, I thought, how can the output voltage be greater the transformer voltage? Please any suggestions. As for me I thought it is the value of the filter capacitor.

[djacobow]

You should repost in beginners.

The transformer output is rated using the RMS AC voltage. The smoothed rectifier output will reflect the AC peak, which is sqrt(2) higher than the RMS voltage.

Lots and lots of information on rectifiers and RMS on the interwebs.

[ataradov]

Start from reading this https://en.wikipedia.org/wiki/Root_mean_square

30 * 1.41 = 42 V, so the peak amplitude on the output of your transformer is 42 V, but RMS voltage is 30 V.

[MosherIV]

Hi, as the others have said, nothing to worry about, that is normal.

What it means is that you have an unregulated 30V power supply.
At full load (drawing 2A) the output will show nearly 10V of ripple, the ps voltage wil rise/fall down to 30V and upto 40V.
With no load, the output voltage will show around 40V

The 'ripple' is due the the capacitor unable to supply enough current to the outout andthe voltage drops.
This should hapoen at a frequency of 100Hz (2x mains freq due to rectification)

wanted to build a voltage regulator

Do you mean, you want to build a regulated power supply?

Is it fixed at 30V with 2A output?