Adapter and charging control method

• US 10,566,829 B2
• Filed: 01/07/2017
• Issued: 02/18/2020
• Est. Priority Date: 02/05/2016
• Status: Expired due to Fees

• Current Assignee: Guangdong OPPO Mobile Telecommunications Corporation Limited
• Original Assignee: Guangdong OPPO Mobile Telecommunications Corporation Limited
• Inventors: Tian, Chen, Zhang, Jialiang
• Primary Examiner(s): Zhou, Zixuan
• Application Number:
  US15/575,788
• Publication Number:
  US 20180145533A1
• Time in Patent Office: 1,137 Days
• Field of Search: 320164
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H02J 2207/10 Control circuit supply, e.g. means for supplying power to the control circuit
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00043 using switches, contacts or markings, e.g. optical, magnetic or barcode
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02J 7/00714 : in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 : in response to battery voltage
• CPC Class Codes: H02J 7/007188 : the charge cycle being controlled or terminated in response to non-electric parameters
• CPC Class Codes: H02J 7/007192 : in response to temperature
• CPC Class Codes: H02J 7/02 : for charging batteries from ac mains by converters
• CPC Class Codes: H02J 7/04 : Regulation of charging current or voltage
• CPC Class Codes: H02J 7/06 : using discharge tubes or semiconductor devices
• CPC Class Codes: H02J 7/2434 : with pulse modulation
• CPC Class Codes: H02M 1/0009 : Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 1/08 : Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 1/44 : Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
• CPC Class Codes: H02M 3/335 : using semiconductor devices only
• CPC Class Codes: H02M 3/33507 : with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 3/33523 : with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33576 : having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: H02M 3/33592 : having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H02M 5/04 : by static converters controlling transformers, reactors or choke coils, e.g. by tap changing H02P13/00
• CPC Class Codes: H02M 7/04 : by static converters
• CPC Class Codes: H02M 7/06 : using discharge tubes without control electrode or semiconductor devices without control electrode
• CPC Class Codes: H02M 7/217 : using semiconductor devices only
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries

Abstract

An adapter and a charging control method are provided, the adapter includes a power conversion unit, a voltage feedback unit, a current feedback unit and a power adjusting unit. An input end of the power adjusting unit is coupled to an output end of the voltage feedback unit and an output end of the current feedback unit respectively, and an output end of the power adjusting unit is coupled to the power conversion unit. The power adjusting unit is configured to receive a voltage feedback signal and a current feedback signal, and to stabilize the output voltage and the output current of the adapter when the voltage feedback signal indicates that the output voltage of the adapter reaches a predetermined target voltage or when the current feedback signal indicates that the output current of the adapter reaches a predetermined target current.

Claims

1. An adapter, comprising:

a power conversion unit, configured to convert an input alternating current to obtain an output voltage and an output current of the adapter;

a voltage feedback unit, wherein an input end of the voltage feedback unit is coupled to the power conversion unit, and the voltage feedback unit is configured to detect the output voltage of the adapter to generate a voltage feedback signal, in which the voltage feedback signal is configured to indicate whether the output voltage of the adapter reaches a predetermined target voltage;

a current feedback unit, wherein an input end of the current feedback unit is coupled to the power conversion unit, and the current feedback unit is configured to detect the output current of the adapter to generate a current feedback signal, wherein the current feedback signal is configured to indicate whether the output current of the adapter reaches a predetermined target current;

a power adjusting unit, wherein an input end of the power adjusting unit is coupled to an output end of the voltage feedback unit and an output end of the current feedback unit respectively, an output end of the power adjusting unit is coupled to the power conversion unit, the power adjusting unit is configured to receive the voltage feedback signal and the current feedback signal, and to stabilize the output voltage and the output current of the adapter when the voltage feedback signal indicates that the output voltage of the adapter reaches the target voltage or when the current feedback signal indicates that the output current of the adapter reaches the target current; and

a charging interface, wherein the adapter is configured to perform a bidirectional communication with the device to be charged via a data wire of the charging interface to negotiate a charging mode between the adapter and the device to be charged;

wherein the voltage feedback unit comprises a first operational amplifier, an output end of the first operational amplifier of the voltage feedback unit is configured to output the voltage feedback signal, the current feedback unit comprises a second operational amplifier, an output end of the second operational amplifier of the current feedback unit is configured to output the current feedback signal;

the power adjusting unit comprises a first diode, a second diode, an optical coupling unit, and a pulse width modulation (PWM) control unit, wherein the output end of the first operational amplifier of the voltage feedback unit is coupled to a cathode of the first diode, an anode of the first diode is coupled to an input end of the optical coupling unit, the output end of the second operational amplifier of the current feedback unit is coupled to a cathode of the second diode, an anode of the second diode is coupled to the input end of the optical coupling unit, an output end of the optical coupling unit is coupled to an input end of the PWM control unit, and an output end of the PWM control unit is coupled to the power conversion unit.

2. The adapter according to claim 1, wherein the adapter further comprises a first adjusting unit, the first adjusting unit is coupled to the voltage feedback unit and configured to adjust a value of the target voltage.

3. The adapter according to claim 2, wherein the voltage feedback unit comprises:

a voltage sampling unit, wherein an input end of the voltage sampling unit is coupled to the power conversion unit, and the voltage sampling unit is configured to sample the output voltage of the adapter to obtain a first voltage;

a voltage comparing unit, wherein an input end of the voltage comparing unit is coupled to an output end of the voltage sampling unit, and the voltage comparing unit is configured to compare the first voltage with a first reference voltage, and to generate the voltage feedback signal based on a result of comparing the first voltage with the first reference voltage;

wherein, the first adjusting unit is coupled to the voltage comparing unit, and configured to provide the first reference voltage for the voltage comparing unit, and to adjust the value of the target voltage by adjusting a value of the first reference voltage.

4. The adapter according to claim 3, wherein the first adjusting unit comprises a control unit and a digital potentiometer, a control end of the digital potentiometer is coupled to the control unit, an output end of the digital potentiometer is coupled to the voltage comparing unit, the control unit is configured to adjust the value of the first reference voltage by adjusting a division ratio of the digital potentiometer.

5. The adapter according to claim 3, wherein the voltage comparing unit comprises a first operational amplifier, an inverting input end of the first operational amplifier of the voltage comparing unit is configured to receive the first voltage, an in-phase input end of the first operational amplifier of the voltage comparing unit is configured to receive the first reference voltage, and an output end of the first operational amplifier of the voltage comparing unit is configured to generate the voltage feedback signal.

6. The adapter according to claim 2, wherein the first adjusting unit is configured to adjust the value of the target voltage based on a first charging mode or a second charging mode presently used by the adapter, in which a charging speed of the adapter charging a device to be charged in the second charging mode is greater than a charging speed of the adapter charging the device to be charged in the first charging mode.

7. The adapter according to claim 1, wherein the adapter further comprises a second adjusting unit, the second adjusting unit is coupled to the current feedback unit and configured to adjust a value of the target current.

8. The adapter according to claim 7, wherein the current feedback unit comprises:

a current sampling unit, wherein an input end of the current sampling unit is coupled to the power conversion unit, and the current sampling unit is configured to sample the output current of the adapter to obtain a second voltage, in which the second voltage is configured to indicate a magnitude of the output current of the adapter;

a current comparing unit, wherein an input end of the current comparing unit is coupled to an output end of the current sampling unit, the current comparing unit is configured to compare the second voltage with a second reference voltage, and to generate the current feedback signal based on a result of comparing the second voltage with the second reference voltage;

wherein, the second adjusting unit is coupled to the current comparing unit, and configured to provide the second reference voltage for the current comparing unit, and to adjust the current value of the target current by adjusting a voltage value of the second reference voltage.

9. The adapter according to claim 8, wherein the second adjusting unit comprises a control unit and a second digital-analog convertor (DAC), an input end of the second DAC is coupled to the control unit, an output end of the second DAC is coupled to the current comparing unit, and the control unit is configured to adjust the voltage value of the second reference voltage via the second DAC.

10. The adapter according to claim 8, wherein the current comparing unit comprises a second operational amplifier, an inverting input end of the second operational amplifier of the current comparing unit is configured to receive the second voltage, an in-phase input end of the second operational amplifier of the current comparing unit is configured to receive the second reference voltage, and an output end of the second operational amplifier of the current comparing unit is configured to generate the current feedback signal.

11. The adapter according to claim 7, wherein the second adjusting unit is configured to adjust the current value of the target current based on a first charging mode or a second charging mode presently used by the adapter, in which a charging speed of the adapter charging a device to be charged in the second charging mode is greater than a charging speed of the adapter charging the device to be charged in the first charging mode.

12. The adapter according to claim 1, wherein the adapter supports a constant voltage charging mode, and in the constant voltage charging mode, the target voltage is a voltage corresponding to the constant voltage mode, and the target current is a maximum current being able to be output by the adapter in the constant voltage mode;

the power adjusting unit is configured to adjust the output voltage of the adapter to the voltage corresponding to the constant voltage mode according to the voltage feedback signal, and to control the output current of the adapter to be not greater than the maximum current being able to be output by the adapter in the constant voltage mode when the current feedback signal indicates that the output current of the adapter reaches the maximum current being able to be output by the adapter in the constant voltage mode.

13. The adapter according to claim 12, wherein the power conversion unit comprises a primary rectifier unit, a transformer, a secondary rectifier unit, and a secondary filter unit, the primary rectifier unit is configured to output a voltage with a pulsating waveform to the transformer directly.

14. The adapter according to claim 13, wherein the maximum current being able to be output by the adapter in the constant voltage mode is determined based on a capacity of a capacitor in the secondary filter unit.

15. The adapter according to claim 1, wherein the adapter supports a constant current charging mode, and in the constant current charging mode, the target voltage is a maximum voltage being able to be output by the adapter in the constant current mode, and the target current is a current corresponding to the constant current mode;

the power adjusting unit is configured to adjust the output current of the adapter to the current corresponding to the constant current mode according to the current feedback signal, and to control the output voltage of the adapter to be not greater than the maximum voltage being able to be output by the adapter in the constant current mode when the voltage feedback signal indicates that the output voltage of the adapter reaches the maximum voltage being able to be output by the adapter in the constant current mode.

16. The adapter according to claim 1, wherein the adapter comprises a control unit, the control unit is configured to perform a bidirectional communication with the device to be charged during the adapter is coupled to the device to be charged, so as to control an output of the adapter in the second charging mode.