Power converter with inrush current limitation

Patent metadata

Field	Value
Publication number	US-9774243-B2
Application number	US-201514956660-A
Country	US
Kind code	B2
Filing date	Dec 2, 2015
Priority date	Apr 7, 2015
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

An AC/DC converter receives an AC voltage at a first terminal and a second terminal. A rectifying bridge has a first input terminal coupled via a resistive element to the first terminal and a second input terminal connected to the second terminal, with output terminals of the rectifying bridge coupled to third and fourth terminals of the converter for generating a DC voltage. A first controllable rectifying thyristor couples the first terminal to the third terminal and a second controllable rectifying thyristor couples the fourth terminal to the first terminal. The resistive element functions as an inrush protection device during a first phase when the thyristors are turned off. In a second phase, the thyristors are selectively actuated.

First claim

The invention claimed is:

1. An AC/DC converter, comprising:
a first terminal and a second terminal configured to receive an AC voltage;
a third terminal and a fourth terminal configured to supply a first DC voltage;
a rectifying bridge having input terminals respectively coupled via a resistive element to the first terminal and connected to the second terminal, and having output terminals respectively connected to the third and fourth terminals;
a first controllable rectifying element coupling the first terminal to the third terminal; and
a second controllable rectifying element coupling the fourth terminal to the first terminal;
wherein the first rectifying element is an anode-gate thyristor controllable by extraction of a first gate current and the second rectifying element is a cathode-gate thyristor controllable by either injection or extraction of a second gate current; and
wherein gates of the anode-gate thyristor and the cathode-gate thyristor are controlled by a same transformer circuit which is excited by an AC signal.

2. The converter of claim 1 , wherein the first and second controllable rectifying elements are controlled to be selectively turned on after a starting phase where the resistive element limits inrush currents is completed.

3. The converter of claim 1 , further comprising:
two series-connected capacitive elements couple the third and fourth terminals, and
a switch connecting a junction point between the capacitive elements to the second terminal.

4. The converter of claim 1 , wherein the first and second rectifying elements are cathode-gate thyristors.

5. An AC/DC converter, comprising:
a first terminal and a second terminal configured to receive an AC voltage;
a third terminal and a fourth terminal configured to supply a first DC voltage;
a rectifying bridge having input terminals respectively coupled via a resistive element to the first terminal and connected to the second terminal, and having output terminals respectively connected to the third and fourth terminals;
a first controllable rectifying element coupling the first terminal to the third terminal; and
a second controllable rectifying element coupling the fourth terminal to the first terminal;
wherein the first rectifying element is an anode-gate thyristor controllable by extraction of a first gate current and the second rectifying element is a cathode-gate thyristor controllable by either injection or extraction of a second gate current; and
wherein gates of the anode-gate thyristor and the cathode-gate thyristor are controlled by a same transformer circuit which is excited by a periodic square wave positive and negative signal.

6. The converter of claim 5 , wherein the first and second controllable rectifying elements are controlled to be selectively turned on after a starting phase where the resistive element limits inrush currents is completed.

7. The converter of claim 5 , further comprising:
two series-connected capacitive elements couple the third and fourth terminals, and
a switch connecting a junction point between the capacitive elements to the second terminal.

8. The converter of claim 5 , wherein the first and second rectifying elements are cathode-gate thyristors.

9. An AC/DC converter, comprising:
a first input terminal and a second input terminal;
a rectifying bridge having a first input coupled via a resistive circuit element to the first terminal and a second input connected to the second input terminal and having a first output and a second output;
a first thyristor having an anode terminal coupled to the second output and a cathode terminal coupled to the first input;
a second thyristor having an anode terminal coupled to the first input and a cathode terminal coupled to the first output; and
a control circuit configured to generate control signals for application to gate terminals of the first and second thyristors.

10. The converter of claim 9 , wherein the control circuit is configured for operation in a first phase wherein the control circuit configures both the first and second thyristors to be turned off with the resistive circuit element functioning to limit inrush current and further configured for operation in a second phase wherein the control circuit configures the first and second thyristors to be selectively turned on to bypass the resistive circuit element.

11. The converter of claim 9 , further including an inductor coupled in series with the input terminal.

12. The converter of claim 9 , further including:
a first inductor coupled between the input terminal and the gate terminals of the first and second thyristors; and
a second inductor magnetically coupled to the first inductor and electrically coupled to an output of the control circuit.

13. The converter of claim 12 , further including:
a first diode coupled between the first inductor and the gate terminal of the first thyristor; and
a second diode coupled between the first inductor and the gate terminal of the second thyristor.

14. The converter of claim 9 , further comprising a first output terminal and a second output terminal coupled, respectively, to the first and second outputs of the rectifying bridge.

15. The converter of claim 9 , wherein the first and second thyristors are both cathode gate type thyristors.

16. The converter of claim 9 , wherein the first thyristor is a cathode gate type thyristor and the second thyristor is an anode gate type thyristor.

17. The converter of claim 9 , wherein the control circuit drives gates of the first and second thyristors using a same transformer circuit which is excited by an AC signal.

18. The converter of claim 9 , wherein the control circuit drives gates of the first and second thyristors using a same transformer circuit which is excited by a periodic square wave positive and negative signal.

Assignees

• St Microelectronics Tours Sas

Inventors

• Gonthier Laurent
• Nina Muriel

Classifications

• H02M2001/325

  Electricity · mapped topic

• H02M1/36 Primary

  Means for starting or stopping converters · CPC title

• H02M1/32 Primary

  Means for protecting converters other than automatic disconnection · CPC title

• H02M7/162

  in a bridge configuration · CPC title

• H02M7/125

  Avoiding or suppressing excessive transient voltages or currents · CPC title