High efficiency, parallel, power conversion system with adaptive dynamic efficiency optimization

• US 11,165,328 B2
• Filed: 10/30/2019
• Issued: 11/02/2021
• Est. Priority Date: 10/30/2018
• Status: Active Grant

• Current Assignee: Smart Prong Technologies, Inc.
• Original Assignee: Agility, LLC
• Inventors: Young, Jason
• Primary Examiner(s): Tran, Thienvu V
• Assistant Examiner(s): Rivera-Perez, Carlos O
• Application Number:
  US16/669,267
• Publication Number:
  US 20200136493A1
• Time in Patent Office: 734 Days
• Field of Search: 363 15- 2103, 363 34, 363 36, 363 65- 72, 363 89, 363 95- 99, 363123, 363124, 363125, 363131-134, 323212-219, 323268, 323271-275, 323282-287, 323299-303, 323351
• CPC Class Codes: H02M 1/0048 Circuits or arrangements for reducing losses using snubbers H02M1/34
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel
• CPC Class Codes: H02M 7/04 by static converters
• CPC Class Codes: H02M 7/08 arranged for operation in parallel
• CPC Class Codes: H02M 7/153 arranged for operation in parallel
• CPC Class Codes: H02M 7/17 arranged for operation in parallel
• CPC Class Codes: H02M 7/23 arranged for operation in parallel H02M7/2176 takes precedence
• CPC Class Codes: H02M 7/44 by static converters
• CPC Class Codes: H02M 7/493 the static converters being arranged for operation in parallel
• CPC Class Codes: H02M 7/77 arranged for operation in parallel
• CPC Class Codes: H02M 7/81 arranged for operation in parallel

Abstract

A system for controlling a plurality of power converters in a power system so as to turn each of the plurality of power converters into an ON state or an OFF state as a function of a sensed input power and a sensed output power such that one or more of the plurality of power converters in the ON state are operating in an optimal power efficiency range.

Claims

1. A system for controlling a plurality of power converters in a power system for supplying power to a load, comprising

a plurality of switched capacitor type power converters forming an array for converting power between a first power level and a second power level when operating, wherein the plurality of switched capacitor type power converters are arranged in parallel relative to each other and wherein each of the switched capacitor type power converters has a plurality of capacitors for storing power,

a common input power line directly coupled to an input of each of the plurality of switched capacitor type power converters on an input side for providing input power at the first power level,

a common output power line directly coupled to an output of each of the plurality of switched capacitor type power converters on an output side for providing output power to the load at the second power level,

a controller directly coupled to the outputs of the plurality of switched capacitor type power converters for controlling a power output of the plurality of switched capacitor type power converters,

an input sensing circuit coupled to the common input power line and to the controller for sensing the input power on the common input power line and transmitting an input power signal to the controller, and

an output sensing circuit coupled to the common output power line and to the controller for sensing the output power on the common output power line and transmitting an output power signal to the controller,

wherein the controller is configured to control each of the plurality of switched capacitor type power converters so as to selectively turn one or more of the plurality of switched capacitor type power converters between

an ON state at a first clock frequency so as to supply power to the load and

an OFF state at a second lower clock frequency where the power converter does not transmit power to the load and remains operative so as to charge the plurality of capacitors associated therewith,

wherein the plurality of switched capacitor type power converters are controlled as a function of the sensed input power and the sensed output power such that one or more of the plurality of switched capacitor type power converters in the ON state are operating in an optimal power efficiency range.

2. The system of claim 1, wherein each of the plurality of switched capacitor type power converters comprises a switched capacitor type DC-DC step-down power converter for converting the power from the first power level to the second power level, where the second power level is lower than the first power level.

3. The system of claim 1, wherein each of the plurality of switched capacitor type power converters comprises a DC-DC power converter, a DC-AC power converter, or a AC-DC power converter.

4. The system of claim 1, wherein the plurality of capacitors are electrically connected in a parallel arrangement, a serial arrangement, a parallel-serial arrangement, or a series-parallel arrangement.

5. The system of claim 1, wherein the controller comprises a processor, a look up table, and a memory for storing instructions that when received by the processor, instructs the processor to:

determine the power across one or more of the plurality of switched capacitor type power converters, and based on the power of the one or more power converters, accessing the look up table and determining therefrom which of the plurality of switched capacitor type power converters the controller places in the ON state and the OFF state.

6. The system of claim 1, wherein the controller comprises

a memory unit for storing instructions for controlling the plurality of switched capacitor type power converters,

a signal conditioner for conditioning the input power signal and the output power signal and generating a conditioned output power signal representative of the instantaneous input power and output power,

an AC-DC converter for converting the conditioned output power signal to a DC conditioned output power signal, and

a processor for processing the DC conditioned output power signal and for generating based on the stored instructions controller output signals for controlling one or more of the plurality of switched capacitor type power converters so as to turn the plurality of switched capacitor type power converters into the ON state and the OFF state, wherein the input power signal has an input voltage component and an input current component and the output power signal has an output voltage component and an output current component, and wherein the signal conditioner further includes

a voltage conditioning unit for buffering the input voltage component and the output voltage component to remove noise therefrom and to scale the input voltage component and the output voltage component to a selected voltage level for use by the controller, and

a current conditioning unit for filtering the input current component and the output current component.

7. The system of claim 6, wherein the conditioned output power signal has a conditioned output voltage component and a conditioned output current component, and wherein the processor comprises

a filter unit for averaging the conditioned output voltage component and the conditioned output current component of the conditioned output power signal,

a power determination unit for determining the power across one or more of the plurality of switched capacitor type power converters based on an average of the conditioned output voltage component and the conditioned output current component and generating a power determination output signal,

a hysteresis unit for reducing noise in the power determination output signal and for passing the power determination output signal to a look-up table only when the power changes by more than a hysteresis amount, and

the look-up table is configured for storing information associated with a plurality of power levels across at least one of the plurality of switched capacitor type power converters correlated to a plurality of switched capacitor type power converters to be placed in the ON state or the OFF state, wherein the information in the look-up table includes the number of the power converters of the plurality of switched capacitor type power converters to be placed in the ON state based on a plurality of different power levels associated with the load while operating the plurality of switched capacitor type power converters in the ON state in the optimal power efficiency range.

8. The system of claim 7, wherein the controller generates one or more output control signals for turning a selected one or more of the plurality of switched capacitor type power converters into the ON state and the OFF state based on the power requirements of the load as correlated to the plurality of switched capacitor type power converters and associated power levels in the look-up table, and based on operating the plurality of switched capacitor type power converters in the ON state in the optimal efficiency range.

9. The system of claim 8, wherein the power levels across at least one of the plurality of switched capacitor type power converters correspond to the power requirements of the load.

10. The system of claim 7, further comprising

a clock selection unit coupled to the controller and to the plurality of switched capacitor type power converters for varying a frequency of one or more of the plurality of switched capacitor type power converters between the first clock frequency for placing the power converter in the ON state and the second clock frequency for placing the power converter in the OFF state, and

a comparison unit coupled to the controller and to the clock selection unit for receiving the conditioned output power signal and the power determination output signal generated by the power determination unit.

11. The system of claim 10, wherein the power determination output signal functions as a first output control signal and wherein the conditioned output power signal includes information related to the input power and to the output power, and wherein the comparison unit receives the conditioned output power signal and the first output control signal which functions as a power threshold signal, and in response generates an output comparison signal when a value associated with the conditioned output power signal is greater than a threshold value associated with the power threshold signal,

wherein when the conditioned output power signal of the signal conditioner has a value greater than the threshold value of the power threshold signal, which is indicative of additional power being required by the power converters, the output comparison signal generated by the comparison unit by-passes the controller and is transmitted to the clock selection unit, which in response transmits an output signal directly to the plurality of switched capacitor type power converters, and

wherein in response to the output comparison signal from the clock selection unit the stored power in the plurality of capacitors of the plurality of switched capacitor type power converters in the OFF state is transmitted directly to the common output power line so as to provide power to the load.

12. The system of claim 10, wherein the clock selection unit comprises one or more clock generators for generating the frequency and a selector for selecting the frequency.

13. The system of claim 6, wherein the current conditioning unit comprises a low pass filter for filtering the input and output current components.

14. The system of claim 1, wherein the first clock frequency for placing the power converter in the ON state is 100 kHz or 200 kHz and the second clock frequency for placing the power converter in the OFF state is 50 kHz.

15. A method of controlling a plurality of power converters in a power system for supplying power to a load, comprising

providing a plurality of switched capacitor type power converters forming an array for converting power between a first power level and a second power level, wherein the plurality of switched capacitor type power converters are arranged in parallel relative to each other and wherein each of the switched capacitor type power converters has a plurality of capacitors for storing power,

providing a common input power line directly coupled to an input of each of the plurality of switched capacitor type power converters on an input side for providing input power at the first power level,

providing a common output power line directly coupled to an output of each of the plurality of switched capacitor type power converters on an output side for providing output power to the load at the second power level,

providing a controller directly coupled to the output of each of the plurality of switched capacitor type power converters for controlling a power output of the plurality of switched capacitor type power converters,

sensing with an input sensing circuit coupled to the controller and to the common input power line input power on the common input power line and transmitting an input power signal to the controller, and

sensing with an output sensing circuit coupled to the controller and to the common output power line output power on the common output power line and transmitting an output power signal to the controller, and

controlling each of the plurality of switched capacitor type power converters so as to selectively turn one or more of the plurality of switched capacitor type power converters between

an ON state at a first clock frequency so as to supply power to the load and

an OFF state at a second lower clock frequency where the power converter does not transmit power to the load and remains operative so as to charge the plurality of capacitors associated therewith, wherein the plurality of switched capacitor type power converters are controlled as a function of the sensed input power and the sensed output power such that one or more of the plurality of switched capacitor type power converters in the ON state are operating in an optimal power efficiency range.

16. The method of claim 15, wherein each of the plurality of switched capacitor type power converters comprises a switched capacitor type DC-DC step-down power converter for converting the power from the first power level to the second power level, where the second power level is lower than the first power level.

17. The method of claim 15, further comprising determining power across one or more of the plurality of switched capacitor type power converters, and based on the power of the one or more of the plurality of switched capacitor type power converters, accessing a look up table and determining therefrom which one of the plurality of switched capacitor type power converters the controller places in the ON state and the OFF state.

18. The method of claim 15, wherein the controller comprises

a memory unit for storing instructions for controlling the plurality of switched capacitor type power converters,

a signal conditioner for conditioning the input power signal and the output power signal and generating a conditioned output power signal representative of the instantaneous input power and output power,

an AC-DC converter for converting the conditioned output power signal to a DC conditioned output power signal, and

a processor for processing the DC conditioned output power signal and for generating based on the stored instructions controller output signals for controlling one or more of the plurality of switched capacitor type power converters so as to turn the plurality of switched capacitor type power converters into the ON state and the OFF state, wherein the input power signal has an input voltage component and an input current component and the output power signal has an output voltage component and an output current component, and wherein the signal conditioner further includes

a voltage conditioning unit for buffering the input voltage component and the output voltage component to remove noise therefrom and to scale the input voltage component and the output voltage component to a selected voltage level for use by the controller, and

a current conditioning unit for filtering the input current component and the output current component.

19. The method of claim 18, wherein the conditioned output power signal has a conditioned output voltage component and a conditioned output current component, and wherein the processor comprises

a filter unit for averaging the conditioned output voltage component and the conditioned output current component of the conditioned output power signal,

a power determination unit for determining the power across one or more of the plurality of switched capacitor type power converters based on an average of the conditioned output voltage component and the conditioned output current component and generating a power determination output signal,

a hysteresis unit for reducing noise in the power determination output signal and for passing the power determination output signal to a look-up table only when the power changes by more than a hysteresis amount, and

the look-up table is configured for storing information associated with a plurality of power levels across at least one of the plurality of switched capacitor type power converters correlated to a plurality of switched capacitor type power converters to be placed in the ON state or the OFF state, wherein the information in the look-up table includes the number of the power converters of the plurality of switched capacitor type power converters to be placed in the ON state based on a plurality of different power levels associated with the load while operating the plurality of switched capacitor type power converters in the ON state in the optimal power efficiency range.

20. The method of claim 19, wherein the controller generates one or more output control signals for turning a selected one or more of the plurality of switched capacitor type power converters into the ON state and the OFF state based on the power requirements of the load as correlated to the plurality of switched capacitor type power converters and associated power levels in the look-up table, and based on operating the plurality of switched capacitor type power converters in the ON state in the optimal efficiency range.

21. The method of claim 15, further comprising conditioning the input power signal and the output power signal and generating a conditioned output power signal, and wherein the conditioned output power signal includes information related to the input power and to the output power varying a frequency of one or more of the plurality of switched capacitor type power converters between the first clock frequency for placing the power converter in the ON state and the second clock frequency for placing the power converter in the OFF state, and comparing a value associated with a control signal generated by the controller with a value associated with the conditioned output power signal which functions as a power threshold signal, and when the value of the conditioned output signal is greater than the value of the control signal, generating a comparison signal when a value associated with the conditioned output power signal is greater than a value associated with the power threshold signal.

22. The method of claim 21, wherein when the power threshold value of the conditioned output power signal of the signal conditioner is greater than the value associated with the controller output signal generated by the controller, which is indicative of additional power being required by the power converters, further comprising in response thereto by-passing the controller and passing the power threshold signal to the clock selection unit, and then in response transmitting stored power in the plurality of capacitors of the plurality of switched capacitor type power converters in the OFF state to the common output power line.

23. The method of claim 15, wherein the controller generates a first output control signal, further comprising conditioning with a signal conditioner the input power signal and the output power signal and generating a conditioned output power signal, varying with a clock selection unit the frequency of one or more of the plurality of switched capacitor type power converters, comparing with a comparison unit the conditioned output power signal and the first output control signal, and in response generating an output comparison signal when a value associated with the conditioned output power signal is greater than a value associated with the first output control signal, transmitting the output comparison signal to the clock selection unit, which in turn transmits an output signal to the plurality of switched capacitor type power converters, and in response to the output signal from the clock selection unit, transmitting the stored power of the plurality of capacitors associated with each of the plurality of switched capacitor type power converters in the OFF state to the output power line.

24. The method of claim 23, wherein the clock selection unit comprises one or more clock generators for generating the frequency and a selector for selecting the frequency.