High voltage direct current soft-start circuit

Patent metadata

Field	Value
Publication number	US-9705303-B2
Application number	US-201514980916-A
Country	US
Kind code	B2
Filing date	Dec 28, 2015
Priority date	Nov 29, 2013
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A high voltage direct current soft-start circuit is provided in which a first end of a first switch is connected to a negative electrode of a high voltage direct current, a first end of a second switch is connected to the negative electrode of the high voltage direct current, and a drive control unit is connected separately to the first switch, the second switch, and a load, where a first part of a connector is connected to the drive control unit, and upon power-on, the first part of the connector communicates with a second part of the connector, to trigger the drive control unit to drive the first switch to turn on. The drive control unit delays a preset time after driving the first switch to turn on, drives the second switch to turn on, and drives the load to start after the second switch is turned on.

First claim

What is claimed is:

1. A high voltage direct current soft-start circuit, comprising:
a drive control unit;
a first switch;
a second switch;
a load; and
a connector having a first connector part and a second connector part,
wherein a first end of the first switch is connected to a negative electrode of a high voltage direct current, a first end of the second switch is connected to the negative electrode of the high voltage direct current, and the drive control unit is connected separately to the first switch, the second switch, and the load, wherein the first connector part is connected to the drive control unit, wherein upon power-on, the first connector part communicates with the second connector part to trigger the drive control unit to drive the first switch to turn on, and wherein the drive control unit delays a preset time after driving the first switch to turn on, drives the second switch to turn on, and drives the load to start after the second switch is turned on.

2. The circuit according to claim 1 , further comprising:
a power resistor; and
a load capacitor,
wherein a second end of the first switch is connected to a first end of the power resistor, and a second end of the second switch is connected to a second end of the power resistor, wherein the second end of the power resistor is connected to a first end of the load capacitor, and a second end of the load capacitor is connected to a positive electrode of the high voltage direct current, and wherein the first end of the load capacitor is connected to a first end of the load, and the second end of the load capacitor is connected to a second end of the load.

3. The circuit according to claim 2 , wherein the first switch is a first metal oxide semiconductor (MOS) transistor, wherein a source electrode of the first MOS transistor is connected to the negative electrode of the high voltage direct current, a gate electrode of the first MOS transistor is connected to the drive control unit, and a drain electrode of the first MOS transistor is connected to the first end of the power resistor, wherein the second switch is a second MOS transistor, and wherein a source electrode of the second MOS transistor is connected to the negative electrode of the high voltage direct current, a gate electrode of the second MOS transistor is connected to the drive control unit, and a drain electrode of the second MOS transistor is connected to the second end of the power resistor.

4. The circuit according to claim 2 , wherein the first switch is a MOS transistor, wherein a source electrode of the MOS transistor is connected to the negative electrode of the high voltage direct current, a gate electrode of the MOS transistor is connected to the drive control unit, and a drain electrode of the MOS transistor is connected to the first end of the power resistor, and wherein the second switch is a relay, wherein a first end of the relay is connected to the negative electrode of the high voltage direct current, a second end of the relay is connected to the second end of the power resistor, and a control pin of the relay is connected to the drive control unit.

5. The circuit according to claim 2 , wherein the first switch is a first relay, wherein a first end of the first relay is connected to the negative electrode of the high voltage direct current, a second end of the first relay is connected to the first end of the power resistor, and a control pin of the first relay is connected to the drive control unit, and wherein the second switch is a second relay, wherein a first end of the second relay is connected to the negative electrode of the high voltage direct current, a second end of the second relay is connected to the second end of the power resistor, and a control pin of the second relay is connected to the drive control unit.

6. The circuit according to claim 2 , wherein the first connector part comprises:
one short pin connected to the drive control unit;
a first long pin connected to a positive electrode pin of the second connector part; and
a second long pin connected to a first negative electrode pin of the second connector part, wherein the short pin is configured to, after coming into contact with a second negative electrode pin of the second connector part upon power-on, cause the connector to generate a connection signal and send the connection signal to the drive control unit.

7. The circuit according to claim 1 , wherein the drive control unit is connected separately to a positive electrode and the negative electrode of the high voltage direct current.

Assignees

• Huawei Tech Co Ltd

Inventors

• Zhang Zhenxing
• Xu Jiansheng
• Chen Nenghu

Classifications

• H02H9/025

  Current limitation using field effect transistors · CPC title

• H02M7/125

  Avoiding or suppressing excessive transient voltages or currents · CPC title

• H02M7/7575

  for high voltage direct transmission link · CPC title

• H02H9/001

  limiting speed of change of electric quantities, e.g. soft switching on or off (progressive control of electronic switches for eliminating interferences H03K17/16) · CPC title

• H02M1/36 Primary

  Means for starting or stopping converters · CPC title