Actively controlled series string power supply
An apparatus, method, and system for actively controlling power in a series string load is provided. A number of conventional low-cost power supply units energize a number of voltage-regulation modules (VRMs) connected to each other in series. Each VRM generates a regulated output voltage using a pulse-wave modulated switching circuit, and provides the regulated output voltage to a number of load elements. Each VRM also sends signals to a central controller describing the output voltage applied to its connected load elements, and adjusts the output voltage applied to its connected load elements in response to signals received from the central controller. The supply voltage provided to individual load elements may thus be accurately and dynamically controlled during operation. Each load element may comprise a light-emitting device, a microprocessor, or a cryptographic integrated circuit with a plurality of processing cores. Optocouplers or load-shifters send signals across different supply voltage domains.
1. An apparatus for actively controlling power in a series string load, the apparatus comprising:
a power supply unit (PSU) providing a DC output voltage;
the series string load, comprising a plurality of load sub-strings, each sub-string comprising one or more load elements connected to each other in series;
a plurality of voltage regulation modules (VRMs), each VRM respectively converting an input voltage from a first input and a second input to produce an output voltage at an output to supply a respective one of the plurality of load sub-strings connected between the output and the second input of each VRM, wherein the respective inputs of the plurality of VRMs are connected together in series with the PSU; and
a central controller that receives signals from each VRM describing an output voltage applied to its respective connected load elements, and responsively transmits signals to each VRM to adjust the output voltage applied to its respective connected load elements;
wherein at least one of the load elements comprises a plurality of processing cores connected together in parallel, wherein the central controller monitors a voltage drop across the plurality of processing cores and selectively disables or enables individual ones of the plurality of processing cores based on the monitored voltage drop to adjust a resistance of the at least one of the load elements.
2. The apparatus of claim 1 wherein the PSU comprises a personal computer power supply.
3. The apparatus of claim 1 wherein each VRM comprises a pulse wave modulation (PWM) controller, an inductor, a capacitor, a first switching device, and a second switching device, wherein the PWM controller generates control signals that alternately switch on the first switching device and the second switching device to send electrical current through the inductor to produce the output voltage, and the capacitor is connected to the output voltage.
4. The apparatus of claim 3 , wherein the first switching device and the second switching device comprise metal-oxide-semiconductor field effect transistors (MOSFETs).
5. The apparatus of claim 3 wherein each VRM adjusts the output voltage applied to its respective load elements by adjusting the PWM controller, in terms of at least one of frequency and duty cycle.
6. The apparatus of claim 1 wherein the plurality of load elements comprise at least one of a light-emitting device, a microprocessor, and a cryptographic integrated circuit with a number of processing cores.
7. The apparatus of claim 1 , wherein the central controller receives additional signals from communication circuits in the respective load elements describing required respective output voltages.
8. The apparatus of claim 1 , wherein at least one of optocouplers and level-shifting circuits communicates the signals from each VRM to the central controller.
9. The apparatus of claim 1 , wherein each load element comprises an internal controller that manages the power supplied to and the operations performed by a plurality of cryptographic integrated circuits.
10. The apparatus of claim 1 , wherein the central controller controls the PSU to adjust its DC output voltage.
11. The apparatus of claim 1 , wherein the central controller comprises a plurality of separate controllers.
12. A method for actively controlling power in a series string load, the method comprising:
distributing power from a power supply unit (PSU) providing a DC output voltage to the series string load, the series string load comprising a plurality of load sub-strings, each sub-string comprising one or more load elements connected to each other in series, using a plurality of voltage regulation modules (VRMs), each VRM respectively converting an input voltage from a first input and a second input to produce an output voltage at an output to supply a respective one of the plurality of load sub-strings connected between the output and the second input of each VRM, wherein the respective inputs of the plurality of VRMs are connected together in series with the PSU;
controlling power distribution using a central controller that receives signals from each VRM describing an output voltage applied to its respective connected load elements, and responsively transmits signals to each VRM to adjust the output voltage applied to its respective connected load elements; and
monitoring, by the central controller, a voltage drop across at least one of the load elements comprising a plurality of processing cores connected together in parallel, and selectively disabling or enabling individual ones of the plurality of processing cores based on the monitored voltage drop to adjust a resistance of the at least one of the load elements.
13. The method of claim 12 wherein each VRM comprises a pulse wave modulation (PWM) controller, an inductor, a capacitor, a first switching device, and a second switching device, and further comprising generating, using the PWM controller, control signals that alternately switch on the first switching device and the second switching device to send electrical current through the inductor to produce the output voltage, and wherein the capacitor is connected to the output voltage.
14. The method of claim 13 further comprising each VRM adjusting the output voltage applied to its respective load elements by adjusting the PWM controller, in terms of at least one of frequency and duty cycle.
15. The method of claim 12 , further comprising the central controller receiving additional signals from communication circuits in the respective load elements describing required respective output voltages.
16. The method of claim 12 , further comprising communicating the signals from each VRM to the central controller using at least one of optocouplers and level-shifting circuits.
17. The method of claim 12 , further comprising controlling the PSU with the central controller to adjust its DC output voltage.
18. The method of claim 12 , wherein the central controller comprises a plurality of separate controllers.
19. A computer program product, comprising a hardware storage medium containing instructions that, when executed by a processor, cause the processor to perform operations comprising:
distributing power from a power supply unit (PSU) providing a DC output voltage to a series string load, the series string load comprising a plurality of load sub-strings, each sub-string comprising one or more load elements connected to each other in series, using a plurality of voltage regulation modules (VRMs), each VRM respectively converting an input voltage from a first input and a second input to produce an output voltage at an output to supply a respective one of the plurality of load sub-strings connected between the output and the second input of each VRM, wherein the respective inputs of the plurality of VRMs are connected together in series with the PSU;
controlling power distribution using a central controller that receives signals from each VRM describing an output voltage applied to its respective connected load elements, and responsively transmits signals to each VRM to adjust the output voltage applied to its respective connected load elements; and
monitoring, by the central controller, a voltage drop across at least one of the load elements comprising a plurality of processing cores connected together in parallel, and selectively disabling or enabling individual ones of the plurality of processing cores based on the monitored voltage drop to adjust a resistance of the at least one of the load elements.
20. The computer program product of claim 19 , wherein each VRM comprises a pulse wave modulation (PWM) controller, an inductor, a capacitor, a first switching device, and a second switching device, and the operations further comprise generating, using the PWM controller, control signals that alternately switch on the first switching device and the second switching device to send electrical current through the inductor to produce the output voltage, and wherein the capacitor is connected to the output voltage.
21. The computer program product of claim 20 , the operations further comprising each VRM adjusting the output voltage applied to its respective load elements by adjusting the PWM controller, in terms of at least one of frequency and duty cycle.
22. The computer program product of claim 19 , the operations further comprising the central controller receiving additional signals from communication circuits in the respective load elements describing required respective output voltages.
23. The computer program product of claim 19 , the operations further comprising communicating the signals from each VRM to the central controller using at least one of optocouplers and level-shifting circuits.
24. A system for actively controlling power in a series string load, the system comprising:
means for supplying power, providing a DC output voltage;
the series string load, comprising a plurality of load sub-strings, each sub-string comprising one or more load elements connected to each other in series;
a plurality of means for regulating voltage, each means for regulating voltage respectively converting an input voltage from a first input and a second input to produce an output voltage at an output to supply a respective one of the plurality of load sub-strings connected between the output and the second input of each means for regulating voltage, wherein the respective inputs of the plurality of means for regulating voltage are connected together in series with the means for supplying power; and
means for controlling that receives signals from each means for regulating voltage describing an output voltage applied to its respective connected load elements, and responsively transmits signals to each means for regulating voltage to adjust the output voltage applied to its respective connected load elements;
wherein at least one of the load elements comprises a plurality of processing cores connected together in parallel, wherein the means for controlling monitors a voltage drop across the plurality of processing cores and selectively disables or enables individual ones of the plurality of processing cores based on the monitored voltage drop to adjust a resistance of the at least one of the load elements.