Charging system with adaptive power management

Patent metadata

Field	Value
Publication number	US-9564772-B2
Application number	US-201213456187-A
Country	US
Kind code	B2
Filing date	Apr 25, 2012
Priority date	Apr 25, 2011
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

An embodiment of a charger may include an input, at least one switch having a first node coupled to a reference voltage, a current sensor coupled between the input and a second node of the at least one switch, an output coupled to a third node of the at least one switch, and a charge controller coupled to the input to determine an input voltage, to the current sensor to determine an input current and to control inputs of the at least one switch. The at least one switch may be responsive to control signals supplied by the charge controller to the control inputs thereof to control voltage and current at the output of the charger. The charge controller may be responsive to the input voltage and the input current to produce the control signals in a manner that maximizes electrical power drawn at the input.

First claim

What is claimed is:

1. A charger, comprising:
an input,
at least one switch having a first node coupled to a reference voltage,
a current sensor coupled between the input and a second node of the at least one switch,
an output coupled to a third node of the at least one switch, and
a charge controller coupled to the input and configured to determine an input voltage, coupled to the current sensor and configured to determine an input current, and coupled to control inputs of the at least one switch, the at least one switch responsive to control signals supplied by the charge controller to the control inputs thereof to control voltage and current at the output of the charger, the charge controller configured to produce the control signals in response to the input voltage and the input current in a manner that approximately maximizes electrical power drawn at the input by causing the electrical power drawn at the input to dither around a maximum value of the electrical power drawn at the input by causing one of the input voltage and the input current to change in a direction, comparing a post-change value of the electrical power drawn at the input to a pre-change value of the electrical power drawn at the input, causing the one of the input voltage and the input current to change again in the direction if the post-change value is greater than the pre-change value, and causing the one of the input voltage and the input current to change in an opposite direction if the post-change value is less than the pre-change value.

2. The charger of claim 1 further comprising a filter coupled between the output and the third node of the at least one switch.

3. The charger of claim 1 wherein the charger controller has a plurality of operating modes including a dynamic power management mode during which electrical power demand at the input exceeds electrical power available at the input, the charge controller configured in the dynamic power management mode to produce the control signals based on a reference control signal,
and wherein the charge controller comprises an adaptive power management unit which is configured to produce the reference control signal, the adaptive power management unit configured to respond to the input voltage and the input current by varying the reference control signal in a manner that approximately maximizes the electrical power drawn at the input by causing the electrical power drawn at the input to dither around the maximum value of the electrical power drawn at the input by causing one of the input voltage and the input current to change in a direction, comparing a post-change value of the electrical power drawn at the input to a pre-change value of the electrical power drawn at the input, causing the one of the input voltage and the input current to change again in the direction if the post-change value is greater than the pre-change value and causing the one of the input voltage and the in out current to change in an opposite direction if the post-change value is less than the pre-change value.

4. The charger of claim 1 wherein the charge control controller is fabricated entirely using analog circuitry.

5. A charger, comprising:
an input,
at least one switch having a first node coupled to a reference voltage,
a current sensor coupled between the input and a second node of the at least one switch,
an output coupled to a third node of the at least one switch, and
a charge controller coupled to the input and configured to determine an input voltage, coupled to the current sensor and configured to determine an input current and coupled to control inputs of the at least one switch, the at least one switch responsive to control signals supplied by the charge controller to the control inputs thereof to control voltage and current at the output of the charger, the charge controller configured to produce the control signals in response to the input voltage and the input current in a manner that approximately maximizes electrical power drawn at the input,
wherein the charger controller has a plurality of operating modes including a dynamic power management mode during which electrical power demand at the input exceeds electrical power available at the input, the charge controller configured in the dynamic power management mode to produce the control signals based on a reference control signal,
wherein the charge controller comprises an adaptive power management unit which is configured to produce the reference control signal, the adaptive power management unit configured to respond to the input voltage and the input current by varying the reference control signal in a manner that approximately maximizes electrical power drawn at the input, and

wherein the adaptive power management unit comprises
a first analog adaptive gain circuit having an input receiving the input voltage and an output producing an adjusted voltage as a product of the input voltage and a first gain value,
a second analog adaptive gain circuit having an input receiving the input current and an output producing an adjusted current as a product of the input current and a second gain value,
a first converter for converting the adjusted voltage to a discrete voltage value and converting the adjusted current to a discrete current value,
a multiplier circuit for producing an input power value as a product of the discrete voltage value and the discrete current value,
a comparison circuit for producing a step value proportional to a difference between the input power value and a previously determined input power value, and
a second converter for converting the step value to the reference control signal.

6. The charger of claim 5 wherein the first analog adaptive gain circuit is responsive to the discrete voltage value to adjust the first gain value such that the discrete voltage value is between predefined low and high values.

7. The charger of claim 5 wherein the second analog adaptive gain circuit is responsive to the discrete current value to adjust the second gain value such that the discrete current value is between predefined low and high values.

8. The charger of claim 5 wherein the first and second analog adaptive gain circuits each comprise analog signal filtering circuitry.

9. The charger of claim 5 wherein the comparison circuitry includes one or more memory registers for storing the input power value therein for comparison with a subsequently determined input power value.

10. A charging system, comprising:
an adapter for converting AC electrical power to a DC electrical power, wherein a DC voltage produced by the adapter decreases rapidly as a DC current produced by the adapter increases above a rated current value,
an electronic device having a power input coupled to at least one electrically chargeable source and to at least one electrical circuit defining a system load, and
a charge control unit having an input coupled to the adapter, an output coupled to the power input of the electronic device, a sensor for sensing the DC current produced by the adapter and producing a current-sense signal, and switching circuitry coupled between the charge control unit input and output and responsive to control signals produced by the charge control unit to controllably supply the DC voltage and the DC current from the adapter to the charge control unit, the charge control unit configured, responsive to the DC voltage produced by the adapter and to the current-sense signal, when a DC current demanded by the electronic device exceeds the rated current, to produce the control signals in a manner that approximately maximizes the DC electrical power produced by the adapter by causing the DC electrical power produced by the ada

Assignees

• Qiu Weihong
• Zhou Xiaozhou
• Liu Jun
• Rodgers Iii Bertram J
• Intersil Americas LLC

Inventors

• Qiu Weihong
• Zhou Xiaozhou
• Liu Jun
• Rodgers Iii Bertram J

Classifications

• H02J7/96

  in response to battery voltage · CPC title

• H02J7/94

  in response to battery current · CPC title

• H02J7/045

  Electricity · mapped topic

• H02J7/022 Primary

  Electricity · mapped topic

• H02J2207/20

  Charging or discharging characterised by the power electronics converter · CPC title