UPS circuit

Patent metadata

Field	Value
Publication number	US-10536030-B2
Application number	US-201515123131-A
Country	US
Kind code	B2
Filing date	Feb 28, 2015
Priority date	Mar 4, 2014
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

A UPS circuit, comprising a rectification phase leg (PL1) for rectification, which is used for converting a received alternating current into a direct current; inversion phase legs (PL21, PL22, PL23) for inversion, which are used for inverting the direct current output by the rectification phase leg into an alternating current; a failure detection device (D) which is used for detecting whether an inversion phase leg has failed; a redundant inversion phase leg (PL2a), with an input end thereof being connected to an output end of the rectification phase leg; and a control device which is used for receiving a signal sent by the failure detection device and is also used for enabling the redundant inversion phase leg to replace the inversion phase leg which has failed when a failure occurs.

First claim

The invention claimed is:

1. An uninterruptible power supply (UPS) circuit, comprising:
a rectification phase leg;
a plurality of first inductors;
a plurality of first inversion phase legs configured to be connected to a load via respective ones of the first inductors in first inverter configuration;
a neutral line;
a control circuit configured to detect a status of respective ones of the first inversion phase legs;
a second inductor; and
a second inversion phase leg, an input end of which is connected to an output end of the rectification phase leg and an output end of which is coupled to the second inductor,
wherein the control circuit is configured to connect the second inversion phase leg to a neutral line via the second inductor for an injection of a zero sequence component into the neutral line when the plurality of first inversion phase legs are configured in the first inverter configuration and to switch the second inversion phase leg and the second inductor from the neutral line to the load to replace a selected one of the first inversion phase legs and a selected one of the first inductors with the second inversion phase leg and the second inductor, respectively, responsive to a failure of the selected one of the first inversion phase legs to form a second inverter configuration that has the same number of phases as the first inverter configuration.

2. The UPS circuit according to claim 1 , wherein the structure of the second inversion phase leg is identical to that of the first inversion, phase legs.

3. The UPS circuit according to claim 1 , wherein the control circuit comprises a switching device configured to connect the second inversion phase leg and the second inductor to an output end of a phase line corresponding to the selected first inversion phase leg and the selected first inductor, so as to replace the selected first inversion phase leg and the selected first inductor.

4. The UPS circuit according to claim 3 , wherein the switching device comprises one or more switches, and when the failure of the selected one of the first inversion phase legs occurs, one of the switches is closed to connect the second inversion phase leg and the second inductor to the output end of the phase line corresponding to the selected first inversion phase leg and the selected first inductor, so as to replace the selected first inversion phase leg and the selected first inductor.

5. The UPS circuit according to claim 1 , wherein the UPS circuit is a 3 phase 3 wire system.

6. The UPS circuit according to claim 5 , wherein the second inversion phase leg and the second inductor act as a balancer to balance a voltage of a DC bus when the plurality of first inversion phase legs are connected in the first inverter configuration.

7. The UPS circuit according to claim 1 , wherein the UPS circuit is a single phase 2 wire system or a 3 phase 4 wire system.

8. An uninterruptible power supply (UPS) comprising:
a multi-phase power converter circuit having a plurality of first inversion phase legs configured to be coupled to a source or load via respective first inductors and a redundant second inversion phase leg and a second inductor; and
a control circuit configured to collectively operate first and second ones of the first inversion phase legs and first and second ones of the first inductors to perform power conversion in a first power converter configuration and to deactivate and replace a failed first one of the first inversion phase legs and the first one of the first inductors with the second inversion phase leg and the second inductor such that the second inversion phase leg, the second one of the first inductors, the second one of the first inversion phase legs, and the second inductor operate collectively to perform power conversion in a second power converter configuration having the same number of phases as the first power converter configuration, wherein the control circuit comprises a switching circuit configured to connect the second inversion phase leg and the second inductor to a neutral line to support an injection of a zero sequence component when the plurality of first inversion phase legs and the first inductors are connected in the first power converter configuration and to connect the second inversion phase leg and the second inductor to an output end of a phase line corresponding to the failed of the first one of the first inversion phase legs and the first one of the first inductors when the power converter circuit is in the second power converter configuration.

9. The UPS of claim 8 , wherein the control circuit is configured to detect a status of the first inversion phase legs and to replace the first one of the first inversion phase legs and the first one of the first inductors with the second inversion phase leg and the second inductor responsive to the detected status.

10. The UPS of claim 9 , wherein the detected status comprises a failure of the one of the first inversion phase legs.

11. The UPS of claim 9 , wherein the first inversion phase legs and the second inversion phase leg are identical.

12. The UPS of claim 9 , wherein the control circuit is configured to detect status of respective ones of the plurality of first inversion phase legs.

13. The UPS of claim 8 , wherein the second inversion phase leg and the second inductor are configured to act as a balancer to balance a voltage of a DC bus first when the first inversion phase legs are connected in the first power converter configuration.

14. An uninterruptible power supply (UPS) comprising:
a multi-phase converter comprising a plurality of first phase legs configured to be coupled to a source or a load via respective first inductors, a second phase leg, and a second inductor; and
a control circuit configured to switch the second phase leg and the second inductor to couple a DC bus to a neutral line for an injection of a zero sequence component into the neutral line in a first mode and to disconnect the second phase leg and the second inductor from the neutral line and switch the second phase leg and the second inductor to the source or the load to replace a failed one of the first phase legs and associated one of the first inductors in a second mode.

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Xu Zhongyong
• Zheng david
• Liao Xizheng

Classifications

• H02J9/063

  Common neutral, e.g. AC input neutral line connected to AC output neutral line and DC middle point · CPC title

• H02J4/00

  Circuit arrangements for mains or distribution networks not specified as AC or DC; Circuit arrangements for mains or distribution networks combining AC and DC sections or sub-networks (arrangements using intermediate DC-AC-DC conversion H02J1/002; arrangements using high-voltage DC [HVDC] links H02J3/36) · CPC title

• H02J9/062 Primary

  for AC powered loads · CPC title

• H02J1/102

  being switching converters (H02J1/108, H02J1/12 take precedence) · CPC title

• H02J3/14

  by switching loads on to, or off from, the networks, e.g. progressively balanced loading · CPC title