It is currently Thu Jul 10, 2014 7:57 am

All times are UTC - 8 hours




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: why don't PSUs do this...
PostPosted: Sun Feb 02, 2003 12:51 pm 
Offline

Joined: Sun Jan 19, 2003 4:47 am
Posts: 218
I've been thinking that a PSU shpould come with a Li-ion battery that it charges up for the first few mins, then shuts itself down before it gets too hot and then back on when the cell is almost drained, having had time to cool down again.

Not sure if this'd help cooling since it'd have to be at higher load to start with, but it could at least charge silently while the PC is turned off and act as a mini UPS. The battery could also provide power for HDDs to flush theeir cache after shutdown.

I've always thought the normal UPS method a bit stupid - mains AC copnverted to DC for cells, back to AC for a PSU which just converts straight back to DC for components! A mini, internal PSU could take up a drive bay or somthing and would be rather more efficent, converting power only once instead of back and forth 3 times!

_________________
jh


Top
 Profile  
 
 Post subject: Re: why don't PSUs do this...
PostPosted: Sun Feb 02, 2003 2:55 pm 
Offline

Joined: Sun Aug 11, 2002 3:26 pm
Posts: 262
Location: Worcester, UK
jhh wrote:
I've been thinking that a PSU shpould come with a Li-ion battery that it charges up for the first few mins, then shuts itself down before it gets too hot and then back on when the cell is almost drained, having had time to cool down again.


Charging batteries is far from efficient, and would create much larger amounts of heat in the PSU than the normal setup - not sure on exact figures but around 10% efficient?


jhh wrote:
Not sure if this'd help cooling since it'd have to be at higher load to start with, but it could at least charge silently while the PC is turned off and act as a mini UPS.


Hmmm, what happens when you want to use it continuously? The inefficiency of batteries would mean your PSU would be powered continuously at a higher power than without using batteries.

jhh wrote:
The battery could also provide power for HDDs to flush their cache after shutdown.


Wasnt aware this was a problem?? Surely it only takes a few seconds?

_________________
Computers should be seen and not heard...


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 02, 2003 2:59 pm 
Offline

Joined: Sun Jan 19, 2003 4:47 am
Posts: 218
k.

I was thinking half as a usual method and half for people like me who need a UPS anyway (the wiring in my building is just shocking, no pun intended)

_________________
jh


Top
 Profile  
 
 Post subject:
PostPosted: Sun Feb 02, 2003 4:39 pm 
Offline

Joined: Sun Jan 26, 2003 1:46 am
Posts: 241
Not a bad idea. Actually, some chargers are even more efficient. It charges in pulses (read PWM... basically same concept). Every 8 charges or so it discharges 1 pulse. This keeps temperature rise down quite a bit as well as prolonging the life of battery. (background knowledge from R/C racing stuff) Another thing I can think of is there really is no need for rapid charging. So... pulse cycle can be slower (even less heat).
Now, using the battery itself still generates heat though. (and quite a bit of it) I would reckon the size of battery that will power PSU for graceful shut down would be at least twice the size of current PSU.

_________________
Lian-Li, P4 2.40GHz@3.6ghz, 9700 Pro @420/351, GEIL PC3700 DDR, IBM 180GXP, Antec Truepower 550 fan modded. Peltier heater in room.
Image


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC - 8 hours


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group