In Reply to: Re: Which PS would you rather listen to? posted by arend-jan on May 8, 2007 at 06:22:06:
Hi!That may well be. I wrote "I think" because I'm not sure. It's been a while since I played with this since I switched to three phase years ago.
Should be easily verifyable by monitoring the volatge across both diodes and see if there is a overlap or a fragment when none conducts.
Then there would a period in which the voltage across both diodes is above the "knee voltage" at the same time.I thought a mechanism like this is in play here: The choke tends to keep the current flowing. Thus the voltage at the end connected to the diode is pulled lower and lower, so the diode keeps conducting. When you scope the voltage at the input side of the choke (or after the rectifier) you will see that it is not just a rectified sinus going from 0 to the crest voltage, but it also sags below zero, which would indicate that the diode would still conduct even if it's input voltage approaches 0. But at a certain point the other diode will start to conduct too.
A scope picture of the secondary voltage points to this direction. It seems as near the zero crossing, the voltage "sticks" for a while. I assumed that is the periode when both diodes are conducting.
But again. I'm just wildly guessing here.
This certainly is the mechanism with three phase supplies. There the insertion of the resistor helps. This causes one diode to stop conduction just before the next begins. Although with this "fix" the current also ceases flowing for a moment, no voltage spike arises.
Best regards
Thomas
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Re: Which PS would you rather listen to? - Thomas Mayer 06:44:42 05/08/07 (9)
- Re: Which PS would you rather listen to? - rdf 07:59:59 05/09/07 (6)
- Re: Which PS would you rather listen to? - Thomas Mayer 08:25:50 05/09/07 (5)
- Re: Which PS would you rather listen to? - rdf 08:52:55 05/09/07 (4)
- Re: Which PS would you rather listen to? - Thomas Mayer 09:34:59 05/09/07 (3)
- Ever compare it to batteries? - Russ57 09:58:00 05/09/07 (2)
- Re: Ever compare it to batteries? - Thomas Mayer 10:45:12 05/09/07 (1)
- I'm about to convert my Phono stage to batteries ... - Naz 05:05:47 05/10/07 (0)
- Re: Which PS would you rather listen to? - Gingertube 16:58:05 05/08/07 (0)
- Re: Which PS would you rather listen to? - danlaudionut 16:01:48 05/08/07 (0)