U.S. patent application number 17/467424 was filed with the patent office on 2022-02-03 for self-aware software defined digital power supply.
This patent application is currently assigned to SOFTIRON LIMITED. The applicant listed for this patent is SOFTIRON LIMITED. Invention is credited to Mark Chen, Norman Fraser, Gary Preston, Phil Straw.
Application Number | 20220037914 17/467424 |
Document ID | / |
Family ID | |
Filed Date | 2022-02-03 |
United States Patent
Application |
20220037914 |
Kind Code |
A1 |
Straw; Phil ; et
al. |
February 3, 2022 |
Self-Aware Software Defined Digital Power Supply
Abstract
A power supply system which connects a DC consumer to an AC
supply includes an AC-DC converter and a UPS. The AC-DC converter
has an input to which alternating current from the AC supply is
applied and an output at which DC current is developed. The UPS has
an input to which direct current from the AC-DC converter is
applied and an output at which DC current is developed. The DC
current developed at the output of the AC-DC converter and DC
current developed at the output of the UPS are applied to the DC
consumer selectively in parallel with each other or exclusively to
each other.
Inventors: |
Straw; Phil; (Newark,
CA) ; Preston; Gary; (Lancashire, GB) ;
Fraser; Norman; (Epsom, Surrey, GB) ; Chen; Mark;
(Newark, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOFTIRON LIMITED |
Chilworth |
|
GB |
|
|
Assignee: |
SOFTIRON LIMITED
Chilworth
GB
|
Appl. No.: |
17/467424 |
Filed: |
September 6, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15503381 |
Feb 10, 2017 |
11114891 |
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PCT/US15/44731 |
Aug 11, 2015 |
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17467424 |
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62036025 |
Aug 11, 2014 |
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International
Class: |
H02J 9/06 20060101
H02J009/06; H02J 7/34 20060101 H02J007/34; H02M 7/04 20060101
H02M007/04 |
Claims
1. A power supply system for connecting a direct current (DC)
consumer to an alternating current (AC) supply comprising: an AC-DC
converter having an input to which an AC from the AC supply is
applied and an output at which a first DC is developed; a universal
power supply (UPS) having an input to which the first DC from the
AC-DC converter is applied and an output at which a second DC is
developed; and a switch configured to switch the AC supply to the
AC-DC converter to control power delivered to the DC consumer.
2. The power supply system of claim 1, wherein the AC-DC converter
is switched on and off by switching the AC supply to the AC-DC
converter.
3. The power supply system of claim 1, wherein the AC supply is
switched to the AC-DC converter to allow tuning of the power supply
system for efficiency to match the UPS.
4. The power supply system of claim 1, wherein the AC supply is
switched to the AC-DC converter to allow charging of a battery of
the UPS with a constant current.
5. The power supply system of claim 4, wherein switching the AC
supply to the AC-DC converter and charging the battery of the UPS
with constant current includes charging the battery of the UPS only
up to voltages that are below a nominal voltage.
6. The power supply system of claim 1, wherein the switching of the
AC supply to the AC-DC converter to control power delivered to the
DC consumer is to be controlled based on a communication generated
by the DC consumer.
7. The power supply system of claim 6, wherein the communication
generated by the DC consumer is based upon information provided to
the DC consumer about operation of the UPS.
8. The power supply system of claim 7, wherein the communication
generated by the DC consumer is based upon information provided to
the DC consumer about operation of the AC-DC converter.
9. The power supply system of claim 7, wherein the communication
generated by the DC consumer is configured to specify that: the DC
consumer will not require power for a higher load for a duration of
time; and during the duration of time, the DC consumer can be
sufficiently powered by the UPS; and the AC-DC converter is
configured to reduce power to the DC consumer and to the UPS during
the duration of time based upon the communication generated by the
DC consumer.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. patent
application Ser. No. 15/503,381, filed Feb. 10, 2017, which is a
U.S. 371 of International Application No. PCT/US2015/044731, filed
Aug. 11, 2015, which claims priority to U.S. Provisional
Application No. 62/036,025, filed Aug. 11, 2014, the entireties of
each of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The current state of the art for power supplies and their
ecosystem is usually singular in the problem it solves. Often power
supplies are design for cost and not efficiency or exception cases.
Often there is only common mode for which the power supply is
optimized and often the optimization is not high. A typical power
supply ecosystem is best seen in FIG. 1.
[0003] The power supply can take many design forms. There is a
wealth of power supply techniques and the topologies and techniques
are well documented, and for many years. There is innovation inside
the power supply but the encompassing the larger scope of the power
train and the power ecosystem is not well refined or optimized.
[0004] Relatively recent awareness of efficiency has driven some
innovation in efficiency, however the broader design has seen
little attention. Energy star is an example of an initial
definition of power efficiency but is narrow in scope and the bar
is low.
[0005] An enabling development for power supply innovation is that
some DC electronic systems are reduced in power relative to
historical norms. An example is the reduction in power of some
computer motherboards. If the power consumption of the DC consumer
is very high, power throughput is mandatory. If power throughput is
moderate or can be limited through cooperation between the DC
consumer and the power supply then innovation over the current
state of the art is possible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIGS. 1-2 show a typical power supply ecosystem; and
[0007] FIGS. 3-5 show an AC-DC topology.
DESCRIPTION OF THE INVENTION
[0008] In accordance with the preset invention, a power supply
ecosystem is seen in FIG. 2. Providing the UPS on the DC side has a
very large change in cost and size versus the resulting duration of
the UPS. In the prior art, a UPS is charged from AC, stores energy
in a battery in DC form after conversion (never 100% efficient),
then inverts the DC when the UPS is needed (AC power removed) and
this is also never 100% efficient. Just to provide a backup to AC
has had two efficiency expenses. The main AC to DC power stage is
typically far from perfectly efficient.
[0009] Collocating the UPS next to the DC consumer allows for
reduced switching speed (glitch less), constant live supply
forgiving brownouts, high efficiency, voltage matching of the
energy store and the DC consumer for efficient conversion on
supply, historical loss of efficiency in charge but high efficiency
in demanded supply leading to low cost and size versus the
resulting duration of the UPS.
[0010] The topology of FIG. 2 also provides that power can be
provided either from the main AC/DC stage of power delivery but
also in parallel from the UPS. This provides a form of redundancy
but beyond that it allows significant changes to the primary AC/DC
stage that would otherwise cause a failure of operation in DC
consumers. One example would be the switch the power supply to the
DC consumer and UPS on and off at the AC source and use the UPS.
This allows the power supply to be tuned for efficiency with one
power specification matched to the UPS. Another use for this
topology is to filter the AC/DC supply to provide accurate power
isolating AC supply events from the DC consumer (other techniques
for this exist but a DC side UPS is novel I believe). Extending on
the last function of filtering the UPS could provide accurate power
and allow the AC/DC stage to be extremely tuned for efficiency of
total energy delivery with poor regulation of supply; variability
of supply to the UPS charging is an easy and well understood
problem to deal with.
[0011] Battery chemistries like Lithium Ion and Lithium polymer
provide many characteristics that are favorable in such a DC side
UPS function. Traditionally these batteries are charged with
constant current and then constant voltage once the batteries
nominal voltage has been reached. By only charging the UPS to
voltages that are below the nominal voltage the batteries can
always be charge with constant current. This forgoes maximal energy
store and in not common, but the novelty and total energy store
loss enables the techniques above to always guarantee a constant
current to the UPS and from the AC/DC stage. None variability on
power supplies allows for tuning for efficiency. Also if a power
supply has a narrow enough specification for power characteristics
very extreme design can result in very high efficiency, but would
not normally be practical because in real world DC consumer
applications very narrow power characteristics are not possible.
But turning the AC on and off and filtering via the DC side UPS all
of this can be enabled.
[0012] Filtering via the DC side UPS provides also for isolation of
the DC load from the AC supply. This provides not only tuning
possibilities in the AC/DC stage but also provides isolation from
inductive and capacitive loads in the DC consumer. This results in
a reduction in the need for power factor correction (PFC). The
AC/DC stage described in the schematic section provides for active
PFC but is allowed to work more efficiently by providing rates of
change and magnitude that is lower. Also providing budget in the
components selection of the design.
[0013] Often a UPS is not indigenous to the DC consumer of its
energy. Often a UPS serves more than one DC consumer. Currently UPS
systems use AC power and the consumers are anonymous.
[0014] If the DC consumer was aware of the UPS and/or it's charge
level it could take actions in its operation relative to that
information. If the AC/DC power supply was monitored in operation
the DC consumer could be informed of its performance and also
second order its health. If the AC power supply were monitored the
collection of information would lead to left awareness. Measurement
of power source and DC consumption would lead to efficiency
information and awareness. Presented to a DC consumer that runs an
operating system this could be configured as a "device." A device
driver would abstract the interface to the power system and allow
two way communication for configuration and
monitoring/notification. Via some communication mechanism (e.g., AC
power comms as discussed below, Data communications like TCP/IP
network) it would be possible to not only monitor power
characteristics but pool groups of equipment per AC circuit, fused
group, backup power group or by any affinity group that provided
useful metadata for power planning, costing, and future planning.
Self-awareness of the power system could allow feedback to the AC
supply system itself. For example a DC consumer could let the AC
system know that it does not plan high load for the next hour, and
that if it did it could use the UPS for supplement. As such AC load
control, temporary source isolation or AC backup power planning
could be allowed. Exemplarily, total power backup delivery may be
reduced and be known to be guaranteed to be adequate. Sharing of
adjacent UPS power between DC consumers would magnify this
effect.
[0015] A stark example of the need for the above is in data centers
that require large amounts of power and large backup
contingencies.
[0016] Self-awareness can be enabled via the two sense diagrams in
the schematics section. Features of these circuits and therefore
values available in a self-aware power supply, OR via a device
driver in a self-aware DC consumer are: [0015] Active, Reactive and
Apparent Power
[0017] Power factor [0017] True RMS Current [0018] RMS Voltage
[0019] Line Frequency
[0018] Real time Voltage [0021] Real time Current [0022] Real-time
Input Power [0023] Temperatures high and low side [0024] Frequency
[0025] DC voltage [0026] DC current [0027] DC power [0028] Peak DC
consumption [0029] Average DC consumption
[0019] By presenting this information as a device driver in an
operating system it allows any application to interface to the
power supply. This may allow adaptive power aware behavior,
notifications about events etc.
[0020] Any communication can deliver the above self-awareness to
allow logging, recording, historical data for planning and audit.
It can provide event data and instrument power at all stages of
consumption.
[0021] Having AC power comms allows the awareness above direct to
the primary source of power without the need for any external comms
infrastructure. The nature of the power data is low bandwidth even
for large numbers of devices and as such it is feasible to use
known AC comms techniques but for power data.
[0022] Second order awareness of peers via the AC communication can
be achieved via monitoring. Device drivers in an operating system
can use this to source information from "remotely mounted devices".
As such all that is needed for awareness monitoring is a self-aware
power system.
[0023] Distributed AC quality monitoring and feedback is also
possible providing benefit to the AC power supplier.
[0024] FIGS. 3-5 show an AC-DC topology. This topology provides
efficiencies approaching 90% and silicon here is modern and
provides minimal need for external components. It also enables
constant voltage and constant current regulation as mentioned
above.
[0025] Transformer losses are a combination of core losses and coil
losses. The core losses consist of those generated by energizing
the laminated steel core. These losses are virtually constant from
no-load to full-load, and for the typical 150 C rise transformer
are about 0.5% of the transformer's full-load rating. The coil
losses are also called load losses because they are proportional to
the load on the transformer. These coil losses make up the
difference between the 0.5% losses for the core and range from 1.5%
to 2% of the total load. Making load constant or at least less
variable and tuning for efficiency of the supply not regulation of
the result is key to efficiency combined with the acknowledgments
about transformers above. Note the mechanism uses two quality
transformers in a flyback design.
[0026] Cooperation as described above is by sharing power awareness
information for planning is a potential source of failure if the
information is not correct. As such this could be a potential
security problem in an attack against infrastructure. As such it
may be important that power supplies are known to be genuine and
that they authenticate themselves to consumers of their power and
their data. As such via communications (e.g.: AC comms) or via a
local bus like I2C on a computer motherboard it makes sense that
anything that mounts a device driver to communicate with the power
supply it is authenticated. A power supply with a device driver
that is authenticated necessarily to function. If AC comms is used
then it has the advantage that power can be denied on failed
authentication, done directly via the AC power source. The owner of
the AC source or facility with AC source can be assured. The
builder of a DC consumer system can be assured the power supply is
known well from a known manufacturer. Manufacturers can be assured
that their products are secured from grey sourcing.
[0027] Application interfacing (and perhaps kernel interaction) may
need to be authenticated for control functions and perhaps
notifications and information updates.
[0028] As such the power supply may have a cryptographic and/or
unique identity. Direct AC or other communication may give the
power supply a MAC address as a network media identity.
Communication from the power supply direct is enabled, and may have
a network level address e.g.: TCP/IP network with an IP address. As
such the power supply could be addressed directly via the
Internet.
[0029] Power supply communication direct to a DC consumer maybe via
a local bus like I2C but USB provides other advantages. For example
existing device classes exist for UPS devices. This may provide
existing infrastructure and applications to work without change or
knowledge of a novel power supply. For example presenting the
device as a USB HID class UPS device would provide awareness of AC
power and battery backup status in existing application and
operating systems.
[0030] By adding a microcontroller into the power supply that
bootstraps from AC and can take power from the UPS energy source it
is possible to communicate with the DC consumer via I2C, USB or
other. Termination of AC comms and other direct communication like
Ethernet can be controlled inside the power supply. Monitoring of
the AC and DC monitors can be coordinated and communicated from the
microcontroller. AC switching, UPS charging, and AC/DC operation
can be controller from the microcontroller. Changes in behavior can
be specified via the comms interfaces or by re-programming via a
USB bootloader.
* * * * *