Device and method for determining a voltage

Patent metadata

Field	Value
Publication number	US-10180446-B2
Application number	US-201515320390-A
Country	US
Kind code	B2
Filing date	Apr 22, 2015
Priority date	Jun 20, 2014
Publication date	Jan 15, 2019
Grant date	Jan 15, 2019

Abstract

The invention relates to a device and to a method for determining a voltage. The voltage to be determined is a direct voltage at the input of a flyback converter. The flyback converter comprises at least a flyback-converter transformer and a switching element on the primary side of the flyback-converter transformer. In order to determine the voltage at the input of the flyback converter, a voltage on the secondary side of the flyback-converter transformer is sensed and evaluated in correlation with the switching state of the switching element on the primary side.

First claim

The invention claimed is:

1. A device for determining a voltage, comprising:
a flyback converter ( 1 ), which includes a flyback-converter transformer (Tr) and a switching element (S 1 ); and
a voltage sensor ( 2 );
wherein the flyback-converter transformer (Tr) has a primary side and a secondary side;
the switching element (S 1 ) is arranged on the primary side of the flyback-converter transformer (Tr); and
the voltage sensor ( 2 ) is arranged on the secondary side of the flyback-converter transformer (Tr) and is configured to sense a voltage depending on a switching state of the switching element (S 1 );
wherein the voltage sensor ( 2 ) senses the voltage at a predetermined time following closure of the switching element (S 1 ).

2. The device as claimed in claim 1 , wherein the voltage sensor ( 2 ) is configured to sense the voltage when the switching element (S 1 ) is opened.

3. The device as claimed in claim 1 , comprising a peak value rectifier ( 30 ) configured to rectify a voltage on the secondary side of the flyback-converter transformer (Tr), wherein the voltage sensor ( 2 ) senses the rectified voltage.

4. The device as claimed in claim 3 , wherein the peak value rectifier ( 30 ) rectifies the voltage on the secondary side of the flyback-converter transformer (Tr) when the switching element (S 1 ) has been closed at least for a predetermined time period.

5. The device as claimed in claim 1 , comprising an evaluating device ( 21 ) which configured to calculate a primary voltage using the sensed voltage and a transfer ratio of the flyback-converter transformer (Tr).

6. An electric drive system, comprising:
an electric energy source;
an electric machine; and
a current converter which is fed by the electric energy source and is configured to actuate the electric machine; and a device for determining an electric voltage as claimed in claim 1 ,
wherein the flyback converter ( 1 ) of the device for determining a voltage is coupled to the electrical energy source.

7. An electric drive system, comprising: an electric energy source;
an electric machine; and
a current converter which is fed by the electric energy source and is configured to actuate the electric machine; and a device for determining an electric voltage as claimed in claim 1 ,
wherein the flyback converter ( 1 ) of the device for determining a voltage is coupled to an intermediate circuit of the current converter.

8. A method ( 100 ) for determining a voltage, including the steps:
providing ( 110 ) a flyback converter ( 1 ) comprising a flyback-converter transformer (Tr) and a first switching element (S 1 ), wherein the flyback-converter transformer (Tr) has a primary side and a secondary side, and the switching element (S 1 ) is arranged on the primary side of the flyback-converter transformer (Tr);
actuating ( 120 ) the first switching element (S 1 );
sensing ( 130 ) a secondary voltage on the secondary side of the flyback-converter transformer (Tr) at a predetermined time following closure of the switching element (S 1 ); and
calculating ( 140 ) a primary voltage which corresponds to an electric voltage on the primary side of the flyback-converter transformer (Tr) using the sensed secondary voltage.

9. The method as claimed in claim 8 , wherein the step ( 130 ) for sensing the secondary voltage senses the secondary voltage when the switching element (S 1 ) is closed.

Assignees

• Bosch Gmbh Robert

Inventors

• Aldinger Stefan
• Koniakowsky Joerg
• Richter Tobias

Classifications

• G01R19/16538

  in AC or DC supplies (G01R19/16519 and G01R19/16528 take precedence) · CPC title

• G01R15/183 Primary

  using transformers with a magnetic core · CPC title

• G01R19/0084

  Measuring voltage only · CPC title

• G01R19/2509

  Details concerning sampling, digitizing or waveform capturing · CPC title

• G01R31/40

  Testing power supplies (testing photovoltaic devices H02S50/10) · CPC title