Step-up or step-down converter comprising a bypass capacitor

Patent metadata

Field	Value
Publication number	US-9654016-B2
Application number	US-201514931324-A
Country	US
Kind code	B2
Filing date	Nov 3, 2015
Priority date	May 3, 2013
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

A converter includes a converter inductor, a converter diode, and a converter switch, wherein the converter inductor, the converter diode and the converter switch operate together to receive an input voltage and generate a converted output voltage. The converter further includes a bypass circuit that is connected in parallel with the converter switch; the bypass circuit includes a bypass capacitor connected in series with a diode, wherein a forward direction of the diode is the same as a regular direction of current flow through the converter switch. The converter also includes a discharge circuit configured to discharge the bypass capacitor, wherein the discharge circuit includes an inductor. The inductor of the discharge circuit is magnetically coupled to the converter inductor.

First claim

The invention claimed is:

1. A converter, comprising:
a converter inductor;
a converter diode;
a converter switch, wherein the converter inductor, the converter diode and the converter switch operate together to receive an input voltage and generate a converted output voltage;
a bypass circuit that is connected in parallel with the converter switch, the bypass circuit comprising a bypass capacitor connected in series with another diode, wherein a forward direction of the another diode is same as a regular direction of current flow through the converter switch; and
a discharge circuit configured to discharge the bypass capacitor, the discharge circuit comprising another inductor,
wherein the another inductor of the discharge circuit is magnetically coupled to the converter inductor,
wherein the converter comprises a plurality of partial converters, each partial converter having a respective converter switch, a respective converter inductor, a respective converter diode, a respective bypass capacitor for the respective converter switch and a respective discharge circuit having a respective another inductor, and wherein the another inductors and the converter inductors of the different partial converters are each magnetically coupled separately from one another.

2. The converter as claimed in claim 1 , wherein the another inductor of the discharge circuit is magnetically coupled to the converter inductor in such a manner that, when a current begins to flow through the converter inductor upon closing of the converter switch, a current flow through the another inductor of the discharge circuit is also initiated and results in the bypass capacitor being discharged.

3. The converter as claimed in claim 1 , wherein the discharge circuit comprises a switching element that is connected in series with the another inductor and has a unidirectional flow direction, wherein the unidirectional flow direction of the switching element and the forward direction of the another diode are opposite one another, as seen from the bypass capacitor.

4. The converter as claimed in claim 3 , wherein the switching element with a unidirectional flow direction comprises a further diode.

5. The converter as claimed in claim 1 , wherein the converter inductor and the another inductor of the discharge circuit comprise air-core inductors.

6. The converter as claimed in claim 1 , wherein the bypass capacitor and the another diode are arranged in the bypass circuit in such a manner that the another diode is connected to a connection of the converter switch via which the converter switch is connected to the converter diode.

7. The converter as claimed in claim 1 , wherein the converter switch and the another diode of the bypass circuit are implemented in a common semiconductor component.

8. The converter as claimed in claim 1 , further comprising a controller configured to control each converter switch for intermittent operation of a respective partial converter.

9. The converter as claimed in claim 1 ,
wherein the converter comprises a step-up converter;
wherein the converter inductor comprises a first SUC inductor;
wherein the converter diode comprises a first SUC diode connected in series with the first SUC inductor;
wherein the converter switch comprises a first SUC switch that is arranged in a shunt branch branching off between the first SUC inductor and the first SUC diode; and
wherein the discharge circuit comprises a first discharge path that branches off between the another diode and the bypass capacitor and is connected to an output-side connection of the first SUC diode.

10. A converter, comprising:
a converter inductor;
a converter diode;
a converter switch, wherein the converter inductor, the converter diode and the converter switch operate together to receive an input voltage and generate a converted output voltage;
a bypass circuit that is connected in parallel with the converter switch, the bypass circuit comprising a bypass capacitor connected in series with another diode, wherein a forward direction of the another diode is same as a regular direction of current flow through the converter switch; and
a discharge circuit configured to discharge the bypass capacitor, the discharge circuit comprising another inductor,
wherein the another inductor of the discharge circuit is magnetically coupled to the converter inductor,
wherein the converter comprises a step-up converter;
wherein the converter inductor comprises a first SUC inductor;
wherein the converter diode comprises a first SUC diode connected in series with the first SUC inductor;
wherein the converter switch comprises a first SUC switch that is arranged in a shunt branch branching off between the first SUC inductor and the first SUC diode;
wherein the discharge circuit comprises a first discharge path that branches off between the another diode and the bypass capacitor and is connected to an output-side connection of the first SUC diode, and
wherein the step-up converter comprises a symmetrical step-up converter that is symmetrical with respect to a center point, comprising
a second SUC inductor,
a second SUC diode connected in series with the second SUC inductor,
a second SUC switch that is arranged in a shunt branch branching off between the second SUC inductor and the second SUC diode,
a second bypass circuit that is connected in parallel with the second SUC switch and in which a second bypass capacitor is connected in series with a second diode, wherein the forward direction of the second diode is same as a regular direction of current flow through the second SUC switch, and
a second discharge circuit for the second bypass capacitor, wherein the second discharge circuit has a second discharge path that branches off between the second diode and the second bypass capacitor and is connected to an output-side connection of the second SUC diode and in which a second inductor is arranged.

11. The converter as claimed in claim 10 , wherein the first SUC inductor, the second SUC inductor, the another inductor of the discharge circuit and the second inductor of the second discharge circuit are magnetically coupled, and wherein the discharge circuit comprises an auxiliary switch that is connected in series with the another inductor of the discharge circuit and is switched on synchronously with the first SUC switch, and the second discharge circuit comprises a second auxiliary switch that is connected in series with the second inductor and is switched on synchronously with the second SUC switch.

12. The converter as claimed in claim 10 , wherein the another inductor of the discharge circuit is magnetically coupled to the converter inductor in such a manner that, when a current begins to flow through the converter inductor upon closing of the converter switch, a current flow through the another inductor of the discharge circuit is also initiated and results in the bypass capacitor being discharged.

13. The converter as claimed in claim 10 , wherein the discharge circuit comprises a switching element that is connected in series with the another inductor and has a unidirectional flow direction, wherein the unidirectional flow direction of the switching element and the forward direction of the another diode are opposite one another, as seen from the bypass capacitor.

14. The converter as claimed in claim 13 , wherein the switching element with a unidirectional flow direction comprises a further diode.

15. A converter, comprising:
a converter inductor;
a converter diode;
a converter switch, wherein the converter inductor, the converter diode and the converter sw

Assignees

• Sma Solar Technology Ag

Inventors

• Sander Stephan
• Gruber Artjom

Classifications

• H02M3/33546 Primary

  with automatic control of the output voltage or current (H02M3/33561 takes precedence) · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title