efficient power conversion solutions
TRANSCRIPT
PowerPoint PresentationSC’07, 11-14-07
From the 380V DC Bus to sub-1V Processors: Efficient Power Conversion Solutions
SC’07, Reno NV, 11-14-07
Stephen Oliver, V•I Chip Inc.
[email protected] , +1 978 749 3256
SC’07, 11-14-07
Abstract
Without a major architectural review, data centers may consume 100 Billion kWhr by 2011. i Additionally, inefficient power and cooling techniques may be the downfall of Moore’s law. ii
One efficiency improvement proposal iii is for the adoption of high voltage DC distribution to enable the AC – 384V stage to be bypassed and the downstream sub-systems (or blades) to be fed directly from the data center distribution busses. This paper represents a follow-on step and proposes high efficiency, high power density power conversion solutions from the HV bus down to processor and low-/medium- and high-power loads.
A baseline sub-system is established with a total load of 1320W:
6x processors (1V, 120A)
6x memory (1.5V, 50A)
Miscellaneous loads (12V, 12.5A)
Potential conversion steps considered are 380V-12V-1V and 380-48-1V with bus converter, synchronous buck converters and factorized power regulators with sine amplitude converters.
Efficiency, power density and annual electrical running cost comparisons are presented.
“Report to Congress on Server and Data Center Energy Efficiency” (p56), U.S. EPA ENERGY STAR Program, Andrew Fanara, August 2, 2007
“The Invisible Crisis in the Data Center: The Economic meltdown of Moore’s Law”. Kenneth Brill, Uptime Institute, 2007
“DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007.
SC’07, 11-14-07
AC-48VDC ‘Silver Box’ + 48-12V DC-DC ‘Brick’ + VRM/VRDs to loads
As designed:
Powered 1.5-2.5V processors, few concerns over energy costs
Over time:
IBA bus converters considered expensive and unnecessary
As a result, use of a 12V-only bus increased
Rect., EMI
AC to 12V ‘silver box’
12V distribution
Rect., EMI
due to duty-cycle limitations
Expensive
Large connectors, heavy bus bars, lots of copper, high electricity bills
Out of date
Only used in new systems due to incumbency and for legacy loads
(e.g. 12V disk drives)
Direct 48V-sub 1V conversion
* “DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007.
SC’07, 11-14-07
Silver Box AC-“post-PFC” 380VDC
Reduces silver box size by >50%
380V distribution direct to blade
Eliminates distribution loss in system
(I2R loss at 380V is 0.1% of 12V loss)
Minimize connector size and cost
380-12V conversion on the blade
Minimize 12V distribution distance
384:12V = 300W @ 95.5%
384:48V = 330W @ 96.5%
U.S. and Foreign Patents and Patents Pending
Cres
D
D
48-1.xV highest efficiency, smallest converter at the load
Minimize 12V on-blade distribution loss
Rect., EMI
Input : Unregulated 48V
PRM + VTM = Isolated, regulated, voltage transformation direct to load
Voltage Transformation Module (VTM)
Performance
Outputs : 0.8 - 55V, up to 100A (13 models)
SC’07, 11-14-07
Direct 48V-to-load conversion with 2 V•I Chips
PRM can be located remotely
Increased space on motherboard / near load
Reduced power dissipation at load
Move POL Capacitance to input of VTM
Reduce capacitance by 1/k^2
Additional space and cost savings
Load
Source
Load
Source
Load
Source
1,000uF
here
1uF
here
Convert 380V to 1.5V, 200A
Total “380V-to-load” Efficiency = 85.2%
Total PCB power component footprint = 4.4 in2 ( 4 chip solution )
With fewer caps, smaller filters, smaller heatsinks
Co-locate HV BCM & PRM, place only the VTM at the load
= highest distribution efficiency (I2R) and least space taken at the load
1.5V
200A
380V
48V
Legacy, Low Power Loads
Step down from 48V to create 12V for legacy / low power loads.
Simple unregulated DC-DC converter
Infrastructure:
SC’07, 11-14-07
Efficiency Comparison: AC-Loads
In all cases, adoption of higher voltage improves efficiency
380V in rack and 48V on blade / motherboard has highest efficiency
+8.7% pts over baseline
+8.7% pts
Reduction of 173W per blade / motherboard vs. baseline
173 W
Utility Savings ( per Year per Blade / Motherboard )
380V in rack and 48V on blade / motherboard has highest saving ($202 per year, per blade / motherboard)
$202
Lower load voltages and larger load domain power
Duty cycle limitation of synchronous buck conversion
Increased I2R distribution loss
Higher voltage (380V and / or 48V) distribution greatly reduces distribution loss
Direct 48-to-load conversion offers high efficiency and small size
Enable up to 8.7% pts efficiency improvement over 12V baseline
Significant running cost savings
References
“Report to Congress on Server and Data Center Energy Efficiency” (p56), U.S. EPA ENERGY STAR Program, Andrew Fanara, August 2, 2007
“The Invisible Crisis in the Data Center: The Economic meltdown of Moore’s Law”. Kenneth Brill, Uptime Institute, 2007
“DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007
“Datacenter Power Delivery Architectures : Efficiency and Annual Operating Costs”, Yeaman (V.I Chip), Digital Power Forum, September 2007
SC’07, 11-14-07
Thank you
Questions & comments?
Visit the V•I Chip booth (#832) for a live 380V-0.8V demo
70
72
74
76
78
80
82
84
86
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
AC-Load Efficiency (%)
150
200
250
300
350
400
450
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
Power Loss per Blade (W)
0
25
50
75
100
125
150
175
200
225
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
Electricity Savings
From the 380V DC Bus to sub-1V Processors: Efficient Power Conversion Solutions
SC’07, Reno NV, 11-14-07
Stephen Oliver, V•I Chip Inc.
[email protected] , +1 978 749 3256
SC’07, 11-14-07
Abstract
Without a major architectural review, data centers may consume 100 Billion kWhr by 2011. i Additionally, inefficient power and cooling techniques may be the downfall of Moore’s law. ii
One efficiency improvement proposal iii is for the adoption of high voltage DC distribution to enable the AC – 384V stage to be bypassed and the downstream sub-systems (or blades) to be fed directly from the data center distribution busses. This paper represents a follow-on step and proposes high efficiency, high power density power conversion solutions from the HV bus down to processor and low-/medium- and high-power loads.
A baseline sub-system is established with a total load of 1320W:
6x processors (1V, 120A)
6x memory (1.5V, 50A)
Miscellaneous loads (12V, 12.5A)
Potential conversion steps considered are 380V-12V-1V and 380-48-1V with bus converter, synchronous buck converters and factorized power regulators with sine amplitude converters.
Efficiency, power density and annual electrical running cost comparisons are presented.
“Report to Congress on Server and Data Center Energy Efficiency” (p56), U.S. EPA ENERGY STAR Program, Andrew Fanara, August 2, 2007
“The Invisible Crisis in the Data Center: The Economic meltdown of Moore’s Law”. Kenneth Brill, Uptime Institute, 2007
“DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007.
SC’07, 11-14-07
AC-48VDC ‘Silver Box’ + 48-12V DC-DC ‘Brick’ + VRM/VRDs to loads
As designed:
Powered 1.5-2.5V processors, few concerns over energy costs
Over time:
IBA bus converters considered expensive and unnecessary
As a result, use of a 12V-only bus increased
Rect., EMI
AC to 12V ‘silver box’
12V distribution
Rect., EMI
due to duty-cycle limitations
Expensive
Large connectors, heavy bus bars, lots of copper, high electricity bills
Out of date
Only used in new systems due to incumbency and for legacy loads
(e.g. 12V disk drives)
Direct 48V-sub 1V conversion
* “DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007.
SC’07, 11-14-07
Silver Box AC-“post-PFC” 380VDC
Reduces silver box size by >50%
380V distribution direct to blade
Eliminates distribution loss in system
(I2R loss at 380V is 0.1% of 12V loss)
Minimize connector size and cost
380-12V conversion on the blade
Minimize 12V distribution distance
384:12V = 300W @ 95.5%
384:48V = 330W @ 96.5%
U.S. and Foreign Patents and Patents Pending
Cres
D
D
48-1.xV highest efficiency, smallest converter at the load
Minimize 12V on-blade distribution loss
Rect., EMI
Input : Unregulated 48V
PRM + VTM = Isolated, regulated, voltage transformation direct to load
Voltage Transformation Module (VTM)
Performance
Outputs : 0.8 - 55V, up to 100A (13 models)
SC’07, 11-14-07
Direct 48V-to-load conversion with 2 V•I Chips
PRM can be located remotely
Increased space on motherboard / near load
Reduced power dissipation at load
Move POL Capacitance to input of VTM
Reduce capacitance by 1/k^2
Additional space and cost savings
Load
Source
Load
Source
Load
Source
1,000uF
here
1uF
here
Convert 380V to 1.5V, 200A
Total “380V-to-load” Efficiency = 85.2%
Total PCB power component footprint = 4.4 in2 ( 4 chip solution )
With fewer caps, smaller filters, smaller heatsinks
Co-locate HV BCM & PRM, place only the VTM at the load
= highest distribution efficiency (I2R) and least space taken at the load
1.5V
200A
380V
48V
Legacy, Low Power Loads
Step down from 48V to create 12V for legacy / low power loads.
Simple unregulated DC-DC converter
Infrastructure:
SC’07, 11-14-07
Efficiency Comparison: AC-Loads
In all cases, adoption of higher voltage improves efficiency
380V in rack and 48V on blade / motherboard has highest efficiency
+8.7% pts over baseline
+8.7% pts
Reduction of 173W per blade / motherboard vs. baseline
173 W
Utility Savings ( per Year per Blade / Motherboard )
380V in rack and 48V on blade / motherboard has highest saving ($202 per year, per blade / motherboard)
$202
Lower load voltages and larger load domain power
Duty cycle limitation of synchronous buck conversion
Increased I2R distribution loss
Higher voltage (380V and / or 48V) distribution greatly reduces distribution loss
Direct 48-to-load conversion offers high efficiency and small size
Enable up to 8.7% pts efficiency improvement over 12V baseline
Significant running cost savings
References
“Report to Congress on Server and Data Center Energy Efficiency” (p56), U.S. EPA ENERGY STAR Program, Andrew Fanara, August 2, 2007
“The Invisible Crisis in the Data Center: The Economic meltdown of Moore’s Law”. Kenneth Brill, Uptime Institute, 2007
“DC Power for Improved Datacenter Efficiency”, Ton (Ecos), Fortenbery (EPRI) & Tschudi (Lawrence Berkeley National Labs), January 2007
“Datacenter Power Delivery Architectures : Efficiency and Annual Operating Costs”, Yeaman (V.I Chip), Digital Power Forum, September 2007
SC’07, 11-14-07
Thank you
Questions & comments?
Visit the V•I Chip booth (#832) for a live 380V-0.8V demo
70
72
74
76
78
80
82
84
86
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
AC-Load Efficiency (%)
150
200
250
300
350
400
450
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
Power Loss per Blade (W)
0
25
50
75
100
125
150
175
200
225
[AC - 12V] - 1.xV[AC-384V] - 12V - 1.xV[AC-384V] - 48V - 1.xV[AC - 48V] - 1.xV
Electricity Savings