Dual input power supply with shortened switching

Patent metadata

Field	Value
Publication number	US-11101684-B2
Application number	US-201916563964-A
Country	US
Kind code	B2
Filing date	Sep 9, 2019
Priority date	Jan 25, 2019
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A power supply method and a power supply apparatus including a power conversion circuit, a first and a second switching circuit, and a control circuit are provided. The power conversion circuit is coupled between a DC power source and a power supply terminal and performs a boosting operation according to a DC voltage of the DC power source to generate a boost voltage. The first switching circuit is coupled between an AC power source and the power supply terminal. The second switching circuit is coupled between the power conversion circuit and the power supply terminal. The control circuit enters a first mode after turning on the first and the second switching circuit, so the first switching circuit transmits a main AC voltage of the AC power source to the power supply terminal in the first mode. The boost voltage is greater than a peak value of the main AC voltage.

First claim

What is claimed is:

1. A power supply apparatus, comprising:
a power conversion circuit coupled between a DC power source and a power supply terminal and configured to perform a boosting operation according to a DC voltage of the DC power source to generate a boost voltage;
a first switching circuit coupled between an AC power source and the power supply terminal;
a second switching circuit coupled between the power conversion circuit and the power supply terminal; and
a control circuit coupled to the power conversion circuit, the first switching circuit and the second switching circuit, wherein the control circuit enters a first mode after turning on the first switching circuit and the second switching circuit, so that the first switching circuit transmits a main AC voltage of the AC power source to the power supply terminal in the first mode, and the boost voltage has been established in advance by the power conversion circuit according to the DC voltage before the control circuit enters the first mode,
wherein a voltage value of the boost voltage is greater than a peak value of the main AC voltage.

2. The power supply apparatus according to claim 1 , wherein
in the first mode, the control circuit determines whether the power conversion circuit is abnormal, and if the control circuit determines that the power conversion circuit is abnormal, the control circuit turns off the second switching circuit.

3. The power supply apparatus according to claim 1 , wherein the control circuit determines whether the AC power source is abnormal in the first mode, and if the AC power source is abnormal, the control circuit turns off the first switching circuit, and the control circuit controls the power conversion circuit to convert the boost voltage to a backup AC voltage and enters a second mode, so that the power conversion circuit outputs the backup AC voltage to the power supply terminal in the second mode.

4. The power supply apparatus according to claim 3 , wherein the power conversion circuit comprises:
a DC to DC conversion circuit coupled to the DC power source and configured to perform the boosting operation according to the DC voltage to generate the boost voltage; and
a DC to AC conversion circuit coupled between the DC to DC conversion circuit and the second switching circuit and configured to be controlled by the control circuit to convert the boost voltage to the backup AC voltage.

5. The power supply apparatus according to claim 3 , wherein
in the first mode, the control circuit records a voltage polarity and a voltage value of the power supply terminal to obtain a detected voltage polarity and a detected voltage value,
wherein if the control circuit determines that the AC power source is abnoiiiial, the control circuit generates a pulse width modulation signal group according to the detected voltage polarity and the detected voltage value, and the power conversion circuit converts the boost voltage to the backup AC voltage according to the pulse width modulation signal group.

6. The power supply apparatus according to claim 3 , wherein
in the second mode, the control circuit determines whether the AC power source returns to normal, and if the AC power source returns to normal, the control circuit controls the power conversion circuit to stop providing the backup AC voltage, turns on the first switching circuit and enters the first mode.

7. The power supply apparatus according to claim 1 , further comprising:
a battery module configured to provide the DC power source; and
a charger circuit coupled between the AC power source and the battery module and being controlled by the control circuit,
wherein the charger circuit generates a charging voltage and a charging current according to the AC power source to charge the battery module in the first mode.

8. A power supply method, comprising:
performing, by a power conversion circuit, a boosting operation according to a DC voltage of a DC power source to generate a boost voltage;
turning on, by a control circuit, a first switching circuit coupled between an AC power source and a power supply terminal;
after the first switching circuit is turned on, turning on, by the control circuit, a second switching circuit coupled between the power conversion circuit and the power supply terminal and entering a first mode; and
in the first mode, transmitting, by the first switching circuit, a main AC voltage of the AC power source to the power supply terminal,
wherein before the control circuit enters the first mode, the boost voltage has been established in advance by the power conversion circuit according to the DC voltage,
wherein a voltage value of the boost voltage is greater than a peak value of the main AC voltage.

9. The power supply method according to claim 8 , further comprising:
in the first mode, determining by the control circuit whether the power conversion circuit is abnormal to obtain a determination result; and
if the determination result is YES, turning off the second switching circuit by the control circuit.

10. The power supply method according to claim 8 , further comprising:
in the first mode, determining by the control circuit whether the AC power source is abnormal to obtain a first determination result;
if the first determination result is YES, turning off the first switching circuit and controlling the power conversion circuit to convert the boost voltage to a backup AC voltage by the control circuit and entering a second mode; and
in the second mode, outputting, by the power conversion circuit, the backup AC voltage to the power supply terminal.

11. The power supply method according to claim 10 , further comprising:
in the first mode, recording, by the control circuit, a voltage polarity and a voltage value of the power supply terminal to obtain a detected voltage polarity and a detected voltage value.

12. The power supply method according to claim 11 , wherein a step of controlling the power conversion circuit to convert the boost voltage to the backup AC voltage comprises:
generating, by the control circuit, a pulse width modulation signal group according to the detected voltage polarity and the detected voltage value; and
converting, by the power conversion circuit, the boost voltage to the backup AC voltage according to the pulse width modulation signal group.

13. The power supply method according to claim 10 , further comprising:
in the second mode, determining by the control circuit whether the AC power source returns to normal to obtain a second determination result; and
if the second determination result is YES, controlling the power conversion circuit to stop providing the backup AC voltage and turning on the first switching circuit by the control circuit and entering the first mode.

14. The power supply method according to claim 8 , further comprising:
providing the DC power source by a battery module; and
generating, by a charger circuit, a charging voltage and a charging current according to the AC power source to charge the battery module in the first mode.

Assignees

• Merry Electronics Shenzhen Co Ltd

Inventors

• Liu Yung-Hsiang
• Liang wei-kang
• Wang yu-kai

Classifications

• H02J9/062

  for AC powered loads · CPC title

• H02M7/44

  by static converters · CPC title

• H02J9/061 Primary

  for DC powered loads · CPC title

• H02M3/156

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• H02M1/007

  Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826) · CPC title