Filter apparatus and power supply system

Patent metadata

Field	Value
Publication number	US-10447225-B2
Application number	US-201715794817-A
Country	US
Kind code	B2
Filing date	Oct 26, 2017
Priority date	Apr 27, 2015
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A filter apparatus, which includes a feedback active common-mode filter and a feed-forward active common-mode filter, the feedback active common-mode filter includes a common-mode noise detection component and a first filter circuit, and the feed-forward active common-mode filter includes the common-mode noise detection component and a second filter circuit, where the first filter circuit is connected between the common-mode noise detection component and the device, and performs feedback filtering on a first common-mode noise signal, to obtain a second common-mode noise signal; the common-mode noise detection component is connected between the first filter circuit and the second filter circuit, detects the second common-mode noise signal, and provides the second filter circuit with the second common-mode noise signal; and the second filter circuit is connected between an external power source and the common-mode noise detection component, and performs feed-forward filtering on the second common-mode noise signal.

First claim

What is claimed is:

1. A filter apparatus, wherein the filter apparatus is connected between an external power source and a device, the filter apparatus is configured to perform filtering processing on a noise signal from the device, the filter apparatus comprises a feedback active common-mode filter and a feed-forward active common-mode filter, the feedback active common-mode filter comprises a common-mode noise detection component and a first filter circuit, and the feed-forward active common-mode filter comprises the common-mode noise detection component and a second filter circuit, wherein
the first filter circuit is connected between the common-mode noise detection component and the device, and the first filter circuit is configured to perform feedback filtering processing on a first common-mode noise signal from the device, to obtain a second common-mode noise signal;
the common-mode noise detection component is connected between the first filter circuit and the second filter circuit, and the common-mode noise detection component is configured to detect the second common-mode noise signal, and provide the second filter circuit with the second common-mode noise signal; and
the second filter circuit is connected between the external power source and the common-mode noise detection component, and the second filter circuit is configured to perform feed-forward filtering processing on the second common-mode noise signal.

2. The filter apparatus according to claim 1 , wherein:
the common-mode noise detection component is further configured to provide the first filter circuit with the second common-mode noise signal; and
the first filter circuit is further configured to perform feedback filtering processing on the second common-mode noise signal.

3. The filter apparatus according to claim 2 , wherein the common-mode noise detection component comprises:
a primary side, configured to detect the second common-mode noise signal; and
a first secondary side, wherein an output end of the first secondary side is connected to an input end of the first filter circuit, and the output end of the first secondary side is further connected to an input end of the second filter circuit, to separately provide the first filter circuit and the second filter circuit with the second common-mode noise signal detected by the primary side.

4. The filter apparatus according to claim 2 , wherein the common-mode noise detection component comprises:
a primary side, configured to detect the second common-mode noise signal;
a second secondary side, wherein an output end of the second secondary side is connected to an input end of the first filter circuit, to provide the first filter circuit with the second common-mode noise signal detected by the primary side; and
a third secondary side, wherein an output end of the third secondary side is connected to an input end of the second filter circuit, to provide the second filter circuit with the second common-mode noise signal detected by the primary side.

5. The filter apparatus according to claim 3 , wherein:
the external power source is a power grid connected to the device by using a power cable comprising a phase wire and a neutral line; and
the primary side comprises:
a first sub-primary side, connected on the phase wire in series, and
a second sub-primary side, connected on the neutral line in series.

6. The filter apparatus according to claim 1 , wherein the first filter circuit comprises: a loop compensation circuit, a first current injection circuit, and a first external power supply circuit, wherein
an input end of the loop compensation circuit is connected to the common-mode noise detection component, and an output end of the loop compensation circuit is connected to an input end of the first current injection circuit, to provide the first current injection circuit with a current signal;
an output end of the first current injection circuit is connected to protection ground, to inject, into the protection ground, the current signal output by the loop compensation circuit; and
the first external power supply circuit is configured to provide the loop compensation circuit with a working voltage.

7. The filter apparatus according to claim 6 , wherein the second filter circuit comprises: a voltage/current conversion circuit, a second current injection circuit, and a second external power supply circuit, wherein
an input end of the voltage/current conversion circuit is connected to the common-mode noise detection component, an output end of the voltage/current conversion circuit is connected to an input end of the second current injection circuit, and the voltage/current conversion circuit is configured to provide the second current injection circuit with a current signal;
an output end of the second current injection circuit is connected to the protection ground, to inject, into the protection ground, the current signal output by the voltage/current conversion circuit; and
the second external power supply circuit is configured to provide the voltage/current conversion circuit with a working voltage.

8. The filter apparatus according to claim 1 , further comprising:
a differential-mode filter connected between the external power source and the second filter circuit and configured to perform filtering processing on a differential-mode noise signal from the device.

9. The filter apparatus according to claim 1 , further comprising:
a high frequency passive common-mode filter connected between the first filter circuit and the device and configured to perform filtering processing on an initial common-mode noise signal from the device, and wherein a first noise signal processed by the first filter circuit is a common-mode noise signal obtained after the initial common-mode noise signal is processed by the high frequency passive common-mode filter.

10. A power supply system, comprising:
a filter apparatus, an external power source, and a device, wherein the filter apparatus is connected between the external power source and the device, and the filter apparatus, the external power source, and the device form a loop by using a line, when the device runs, a first common-mode noise signal is generated on the line;
wherein the filter apparatus comprises a feedback active common-mode filter and a feed-forward active common-mode filter, the feedback active common-mode filter comprises a common-mode noise detection component and a first filter circuit, and the feed-forward active common-mode filter comprises the common-mode noise detection component and a second filter circuit, wherein
the first filter circuit is connected between the common-mode noise detection component and the device, and the first filter circuit is configured to perform feedback filtering processing on the first common-mode noise signal from the device, to obtain a second common-mode noise signal;
the common-mode noise detection component is connected between the first filter circuit and the second filter circuit, and the common-mode noise detection component is configured to detect the second common-mode noise signal, and provide the second filter circuit with the second common-mode noise signal; and
the second filter circuit is connected between the external power source and the common-mode noise detection component, and the second filter circuit is configured to perform feed-forward filtering processing on the second common-mode noise signal.

Assignees

• Huawei Tech Co Ltd

Inventors

• Pei Changsheng
• Gao Yongbing
• Zhang Heling

Classifications

• H02J3/00142 Primary

  Oscillations concerning frequency · CPC title

• Y02E40/40

  Arrangements for reducing harmonics · CPC title

• H02J3/1835

  with stepless control · CPC title

• H02M1/12

  Arrangements for reducing harmonics from AC input or output · CPC title

• Y02E40/30

  Reactive power compensation · CPC title