Uninterruptible power supply circuit

Patent metadata

Field	Value
Publication number	US-9520718-B2
Application number	US-201414533439-A
Country	US
Kind code	B2
Filing date	Nov 5, 2014
Priority date	Jul 5, 2013
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

An uninterruptible power supply circuit is provided. The uninterruptible power supply circuit includes a bidirectional selector switch, a first-type bidirectional converter, a second-type bidirectional converter, an energy storage apparatus, and a filtering apparatus, and is alternatively connected to an alternating-current power supply and the energy storage apparatus by using the bidirectional selector switch; the first-type bidirectional converter is disposed between the bidirectional selector switch and the filtering apparatus, the second-type bidirectional converter is disposed between the filtering apparatus and a load, and both the first-type bidirectional converter and the second-type bidirectional converter have a function of rectifying or inverting. By using a bidirectional converter and a bidirectional selector switch, alternating-current commercial power, the energy storage apparatus, and a charger required by the energy storage apparatus can share the bidirectional converter; compared with an existing uninterruptible power supply circuit, no extra charger or high-power conversion circuit is required.

First claim

What is claimed is:

1. An uninterruptible power supply circuit, comprising:
a bidirectional selector switch;
a first-type bidirectional converter;
a second-type bidirectional converter;
an energy storage apparatus;
a filtering apparatus; and
a controller,
wherein a first end of the bidirectional selector switch is connected to an alternating-current end of the first-type bidirectional converter, a second end is alternatively connected to an alternating-current power supply or the energy storage apparatus, and a control end is connected to a first output end of the controller,
wherein a direct-current end of the first-type bidirectional converter is connected to the filtering apparatus, a control end is connected to a second output end set of the controller, and an operating status of the first-type bidirectional converter comprises rectifying, inverting, boosting or bucking,
wherein a direct-current end of the second-type bidirectional converter is connected to the filtering apparatus, an alternating-current end is connected to a load, a control end is connected to a third output end set of the controller, and an operating status of the second-type bidirectional converter comprises inverting or rectifying, and
wherein the controller is configured to:
generate a control signal for controlling the bidirectional selector switch to connect to the energy storage apparatus when the energy storage apparatus needs to be charged,
generate a control signal for controlling the first-type bidirectional converter to be in a bucking state when the energy storage apparatus needs to be charged,
generate a control signal for controlling the second-type bidirectional converter to be in a rectifying state when the energy storage apparatus needs to be charged,
output the control signal for controlling the bidirectional selector switch to connect to the energy storage apparatus when the energy storage apparatus discharges,
generate a control signal for controlling the first-type bidirectional converter to be in a boosting state when the energy storage apparatus discharges, and
generate a control signal for controlling the second-type bidirectional converter to be in an inverting state when the energy storage apparatus discharges.

2. The uninterruptible power supply circuit according to claim 1 , wherein the bidirectional selector switch comprises a relay.

3. The uninterruptible power supply circuit according to claim 1 , wherein the bidirectional selector switch comprises a bidirectional thyristor.

4. The uninterruptible power supply circuit according to claim 1 , wherein the bidirectional selector switch is a single-pole double-throw relay, a first movable end of the single-pole double-throw relay is connected to the alternating-current power supply, a second movable end is connected to the energy storage apparatus, a fixed end is connected to the alternating-current end of the first-type bidirectional converter, and two ends of a coil are connected to the controller.

5. The uninterruptible power supply circuit according to claim 1 , wherein the bidirectional selector switch comprises a first-type bidirectional selector switch and a second-type bidirectional selector switch, wherein a first end of the first-type bidirectional selector switch is connected to the alternating-current power supply, a second end is connected to the alternating-current end of the first-type bidirectional converter, and a control end is connected to the controller, and wherein a first end of the second-type bidirectional selector switch is connected to the energy storage apparatus, a second end is connected to the alternating-current end of the first-type bidirectional converter, and a control end is connected to the controller.

6. The uninterruptible power supply circuit according to claim 5 , wherein both the first-type bidirectional selector switch and the second-type bidirectional selector switch are single-throw relays, a first normally opened contact of the single-throw relay is the first end of the bidirectional selector switch, a second normally opened contact of the single-throw relay is the second end of the bidirectional selector switch, and as control ends of the bidirectional selector switch, two ends of a coil of the single-throw relay are connected to the controller.

7. The uninterruptible power supply circuit according to claim 5 , wherein when both the first-type bidirectional selector switch and the second-type bidirectional selector switch are bidirectional thyristors, a first end of the bidirectional thyristor is the first end of the bidirectional selector switch, a second end of the bidirectional thyristor is the second end of the bidirectional selector switch, and a gate of the bidirectional thyristor is the control end of the bidirectional selector switch and is connected to the controller.

8. The uninterruptible power supply circuit according to claim 5 , wherein when the alternating-current power supply is a three-phase alternating-current power supply, the first-type bidirectional selector switch comprises a first bidirectional selector switch, a second bidirectional selector switch, and a third bidirectional selector switch, wherein the second-type bidirectional selector switch comprises a fourth bidirectional selector switch, a fifth bidirectional selector switch, and a sixth bidirectional selector switch, wherein the first-type bidirectional converter comprises a first bidirectional converter, a second bidirectional converter, and a third bidirectional converter, wherein the second-type bidirectional converter comprises a fourth bidirectional converter, a fifth bidirectional converter, and a sixth bidirectional converter, wherein a first end of the first bidirectional selector switch is connected to an alternating-current end of the first bidirectional converter, a second end is connected to a phase A of the three-phase alternating-current power supply, and a control end is connected to the controller, wherein a first end of the second bidirectional selector switch is connected to an alternating-current end of the second bidirectional converter, a second end is connected to a phase B of the three-phase alternating-current power supply, and a control end is connected to the controller, wherein a first end of the third bidirectional selector switch is connected to an alternating-current end of the third bidirectional converter, a second end is connected to a phase C of the three-phase alternating-current power supply, and a control end is connected to the controller, wherein a first end of the fourth bidirectional selector switch is connected to the alternating-current end of the first bidirectional converter, a second end is connected to the energy storage apparatus, and a control end is connected to the controller, wherein a first end of the fifth bidirectional selector switch is connected to the alternating-current end of the second bidirectional converter, a second end is connected to the energy storage apparatus, and a control end is connected to the controller, wherein a first end of the sixth bidirectional selector switch is connected to the alternating-current end of the third bidirectional converter, a second end is connected to the energy storage apparatus, and a control end is connected to the controller, wherein direct-current ends of the first bidirectional converter, the second bidirectional converter, and the third bidirectional converter are all connected to the filtering apparatus, wherein direct-current ends of the fourth bidirectional converter, the fifth bidirectional converter, and the sixth bidirectional converter are all connected to the filtering apparatus, and alternating-current ends are all connected to a load, wherein the controller is configured

Assignees

• Huawei Tech Co Ltd

Inventors

• Cui Zhaoxue

Classifications

• H02J4/25

  for transfer of electric power between AC and DC networks, e.g. for supplying the DC section within a load from an AC mains system · CPC title

• Y10T307/625

  Cross-Sectional Technologies · mapped topic

• H02M7/797

  using semiconductor devices only · CPC title

• H02J7/02 Primary

  for charging batteries from AC mains by converters · CPC title

• H02J3/005 Primary

  Electricity · mapped topic