CHARGING DEVICE AND CONTROL METHOD THEREOF

• US 20180062406A1
• Filed: 01/20/2017
• Published: 03/01/2018
• Est. Priority Date: 08/24/2016
• Status: Active Grant

• Current Assignee: Compal Electronics Incorporated
• Original Assignee: Compal Electronics Incorporated
• Inventors: Yang, Yaun-Ren, Yang, Chia-Ning
• Granted Patent: US 10,148,110 B2
• Time in Patent Office: Days
• 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 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: H02J 9/007 Detection of the absence of a load

Abstract

A charging device and a control method for the charging device are provided. The charging device includes an AC/DC converting circuit and a main controller. The main controller includes a first modulation module and a second modulation module. The operation of the switching circuit controlled by the second modulation module consumes less amount of electric energy than the operation of the switching circuit controlled by the first modulation module. When the charging device is in the heavy load condition, the first modulation module is enabled to control the operation of the switching circuit. When the charging device is in the light load condition or the no load condition, the second modulation module is enabled to control the operation of the switching circuit. Consequently, the power consumption of the charging device in the light load condition or the no load condition is reduced.

Claims

1. A charging device, comprising:

an AC/DC converting circuit comprising a switching circuit, wherein during an operation of the switching circuit, the AC/DC converting circuit converts an AC input power into a DC output power and generates plural parameter signals corresponding to the DC output power; and

a main controller electrically connected with the AC/DC converting circuit for controlling the AC/DC converting circuit, wherein the main controller comprises a switch control circuit, a first modulation module and a second modulation module, wherein the first modulation module generates a first control signal to control the switching circuit when the first modulation module is enabled, the second modulation module generates a second control signal to control the switching circuit when the second modulation module is enabled, a first end of the switch control circuit is electrically connected with the switching circuit, a second end of the switch control circuit is electrically connected with the first modulation module and the second modulation module, and the switch control circuit selectively enables the first modulation module or the second modulation module to generate the first control signal or the second control signal to the switching circuit, wherein the operation of the switching circuit according to the second control signal consumes less amount of electric energy than the operation of the switching circuit according to the first control signal,

wherein when the switch control circuit is operated in a condition control mode, the switch control circuit judges whether a load condition of the charging device is maintained in or changed to a heavy load condition, a light load condition or a no load condition according to the plural parameter signals and the first control signal or the second control signal, wherein if the switch control circuit judges that the load condition of the charging device is in the heavy load condition, the switch control circuit enables the first modulation module and disables the second modulation module, wherein if the switch control circuit judges that the load condition of the charging device is in the light load condition or the no load condition, the switch control circuit disables the first modulation module and enables the second modulation module.

2. The charging device according to claim 1, wherein after the charging device is turned on, the switch control circuit is operated in an initial control mode, and the switch control circuit sets a default load condition of the charging device to be one of the heavy load condition, the light load condition and the no load condition, wherein if the default load condition of the charging device is the heavy load condition, the switch control circuit enables the first modulation module to generate the first control signal and acquires information about a bandwidth and a frequency of the first control signal, wherein if the default load condition of the charging device is the light load condition or the no load condition, the switch control circuit enables the second modulation module to generate the second control signal and acquires information about a bandwidth of the second control signal and a frequency of the second control signal.

3. The charging device according to claim 2, wherein the switching circuit comprises a transistor, and the switching circuit comprises a control terminal, a first conduction terminal and a second conduction terminal, wherein the control terminal is electrically connected with the switch control circuit for receiving the first control signal or the second control signal, and a path between the first conduction terminal and the second conduction terminal is conducted or shut off according to the first control signal or the second control signal, wherein when the path between the first conduction terminal and the second conduction terminal is conducted, a conduction current flows through the first conduction terminal and the second conduction terminal.

4. The charging device according to claim 3, wherein the AC/DC converting circuit further comprises a feedback circuit, and the feedback circuit is electrically connected with the switch control circuit and the AC/DC converting circuit, wherein when AC/DC converting circuit outputs the DC output power, a feedback current corresponding to the DC output power DC-OUT is outputted from the feedback circuit to the switch control circuit.

5. The charging device according to claim 4, wherein the plural parameter signals include the conduction current and the feedback current.

6. The charging device according to claim 5, wherein if the switch control circuit is in the condition control mode and the charging device is in the heavy load condition, the switch control circuit judges whether the load condition of the charging device is maintained in the heavy load condition or changed to the light load condition or the no load condition according to the conduction current, the feedback current and the bandwidth of the first control signal and according to a first condition judgment table in the switch control circuit, wherein if the switch control circuit is in the condition control mode and the charging device is in the light load condition, the switch control circuit judges whether the load condition of the charging device is maintained in the light load condition or changed to the heavy load condition or the no load condition according to the conduction current, the feedback current and the frequency of the second control signal and according to a second condition judgment table in the switch control circuit, wherein if the switch control circuit is in the condition control mode and the charging device is in the no load condition, the switch control circuit judges whether the load condition of the charging device is maintained in the no load condition or changed to the heavy load condition or the light load condition according to the conduction current, the feedback current, the bandwidth of the second control signal and the frequency of the second control signal and according to a third condition judgment table in the switch control circuit.

7. The charging device according to claim 6, wherein the first condition judgment table records relationships between the load condition of the charging device, the conduction current, the feedback current and the bandwidth of the first control signal, and the switch control circuit uses the first condition judgment table to judge whether the load condition of the charging device is maintained in the heavy load condition or changed to the light load condition or the no load condition.

8. The charging device according to claim 6, wherein the second condition judgment table records relationships between the load condition of the charging device, the conduction current, the feedback current and the frequency of the second control signal, and the switch control circuit uses the first condition judgment table to judge whether the load condition of the charging device is maintained in the light load condition or changed to the heavy load condition or the no load condition.

9. The charging device according to claim 6, wherein the third condition judgment table records relationships between the load condition of the charging device, the conduction current, the feedback current, the bandwidth of the second control signal and the frequency of the second control signal, and the switch control circuit uses the first condition judgment table to judge whether the load condition of the charging device is maintained in the no load condition or changed to the heavy load condition or the light load condition.

10. The charging device according to claim 6, wherein the first modulation module comprises a pulse width modulation circuit, and the pulse width modulation circuit is electrically connected with the switch control circuit to generate the first control signal, wherein the first control signal is a pulse width modulation signal.

11. The charging device according to claim 6, wherein the second modulation module comprises a pulse frequency modulation circuit, an amplitude modulation circuit and a green mode modulation circuit, which are electrically connected with the switch control circuit to generate the second control signal, wherein the second control signal generated by the pulse frequency modulation circuit is a pulse frequency modulation signal, the second control signal generated by the amplitude modulation circuit is an amplitude modulation signal, and the second control signal generated by the green mode modulation circuit is a green mode modulation signal.

12. The charging device according to claim 11, wherein when the charging device is in the light load condition or the no load condition, the switch control circuit updates the second control signal according to the conduction current, the feedback current, the bandwidth of the second control signal and the frequency of the second control signal and according to an activation judgment table in the switch control circuit.

13. The charging device according to claim 12, wherein the activation judgment table records relationships between an enabled circuit of the second modulation module, the conduction current, the feedback current, the bandwidth of the second control signal and the frequency of the second control signal, and the switch control circuit determines which of the pulse frequency modulation circuit, the amplitude modulation circuit and the green mode modulation circuit is enabled according to the activation judgment table.

14. The charging device according to claim 11, wherein the second modulation module further comprises a single-level modulation circuit, and the single-level modulation circuit is electrically connected with the switch control circuit, wherein when the charging device is in the no load condition, the switch control circuit enables the single-level modulation circuit to generate the second control signal, wherein the second control signal is a single-level signal.

15. A control method for a charging device, the charging device comprising an AC/DC converting circuit and a main controller, the AC/DC converting circuit comprising a switching circuit, the main controller being electrically connected with the AC/DC converting circuit, the main controller comprising a switch control circuit, a first modulation module and a second modulation module, the first modulation module generating a first control signal to control an operation of the switching circuit when the first modulation module is enabled, the second modulation module generating a second control signal to control the operation of the switching circuit when the second modulation module is enabled, a first end of the switch control circuit being electrically connected with the switching circuit, a second end of the switch control circuit being electrically connected with the first modulation module and the second modulation module, the switch control circuit selectively enables the first modulation module or the second modulation module to generate the first control signal or the second control signal to the switching circuit, the operation of the switching circuit according to the second control signal consuming less amount of electric energy than the operation of the switching circuit according to the first control signal, the control method comprising steps of:

(a) controlling the operation of the switching circuit according to the first control signal or the second control signal, so that the AC/DC converting circuit converts an AC input power into a DC output power and generates plural parameter signals corresponding to the DC output power;

(b) allowing the switch control circuit to enter a condition control mode, wherein in the condition control mode, the switch control circuit judges whether a load condition of the charging device is maintained in or changed to a heavy load condition, a light load condition or a no load condition according to the plural parameter signals and the first control signal or the second control signal; and

(c) enabling the first modulation module and disabling the second modulation module if the switch control circuit judges that the load condition of the charging device is in the heavy load condition, and disabling the first modulation module and enabling the second modulation module if the switch control circuit judges that the load condition of the charging device is in the light load condition or the no load condition.