sPHENIX discussion of the superconducting solenoid

["Yip, Kin" <kinyip AT bnl.gov>]

Hi Brian,

 

Our last estimate for the power supply was 2*4600 A * 1V = 9.2 kW (as there are effectively 2 SCR’s at any given time).   Pablo Rosas and Jon Sandberg looked at more detailed information for the SCR for that sPHENIX

power supply, he said that to be conservative, 1 V should really be 1.3 V (see below).   So, the power consumption is :

 

2*4600*1.3 = 11.96 kW.      ( Conservative 😊 )

 

Kin

 

=========================================================================================================================================

 

From: Sandberg, Jon N <jsandberg AT bnl.gov>
Sent: Wednesday, October 14, 2020 11:45 AM
To: Yip, Kin <kinyip AT bnl.gov>
Cc: Marneris, Ioannis M <marneris AT bnl.gov>; Lambiase, Robert <lambiase AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>; Schultheiss, Carl <carls AT bnl.gov>
Subject: RE: SCR has 1 V ?

 

Dear Kin:

 

Pablo has sent me the information on the SCR’s used in the sPHENIX power supply.  To be conservative we should use 1.3 volts as the forward voltage drop of each of the SCR’s instead of 1 volt.    Therefore, the power will be about 12 kW not 9.2 kW…….Jon

Power in the

From: Lambiase, Robert
Sent: Tuesday, October 06, 2020 10:39 AM
To: Yip, Kin <kinyip AT bnl.gov>; Rosas, Pablo J <rosas AT bnl.gov>
Cc: Marneris, Ioannis M <marneris AT bnl.gov>; Sandberg, Jon N <jsandberg AT bnl.gov>
Subject: RE: SCR has 1 V ?

 

Hi All,

 

I attached this quick sketch to show why there are two SCRs conducting at any given time.

 

I use a six pulse as an example.  If it’s a twelve pulse, there are four SCRs conducting at half the current, which is about the same power.

 

Bob

 

From: Yip, Kin <kinyip AT bnl.gov>
Sent: Tuesday, October 6, 2020 10:36 AM
To: Rosas, Pablo J <rosas AT bnl.gov>
Cc: Marneris, Ioannis M <marneris AT bnl.gov>; Sandberg, Jon N <jsandberg AT bnl.gov>; Lambiase, Robert <lambiase AT bnl.gov>
Subject: RE: SCR has 1 V ?

 

Hi,

 

Thanks !

 

Bob told me that at any given time, it’s like 2 SCR taking the 4600 A (total current) and so the total power is

voltage * 4600 A.    Bob thinks that for this type of SCR power supply, the voltage is ~1 V ?  ( So, if it’s 1 V,

power ~ 2*1*4600 W = 9.2 kW. )

 

If you find out and let me know what the exact voltage is, it’ll be great !

 

Kin