Current detection device and method for sensing an electrical current

Patent metadata

Field	Value
Publication number	US-2016349775-A1
Application number	US-201415117513-A
Country	US
Kind code	A1
Filing date	Dec 19, 2014
Priority date	Feb 13, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

The invention relates to the evaluation of a variable of an electric current in a power path by evaluating another electric current in a measuring path. To avoid excessively large electric currents in the measuring path, the current in said path is limited to a predetermined maximum limit value.

First claim

1 . A current detection device ( 10 ) for sensing an electric current (I Sense ) in a measuring path, which conducts an electric current that corresponds to an electric current (I E ) in a power path, the current detection device comprising:
a current measuring device ( 11 ), which is disposed in the measuring path and is designed to provide an output signal that corresponds to an electric current flowing through said current measuring device ( 11 ); and a current limiting device ( 12 ), which is designed to limit the electric current through the current measuring device ( 11 ) to a predetermined maximum limit value.

2 . The current detection device ( 10 ) according to claim 1 , wherein the current measuring device ( 11 ) is designed to provide a voltage signal which is proportional to the electric current that flows through said current measuring device ( 11 ).

3 . The current detection device ( 10 ) according to claim 1 , wherein the current measuring device ( 11 ) comprises an analog/digital converter, which is designed to convert the output signal dependent on the electric current through the current measuring device ( 11 ) into a digital signal.

4 . The current detection device ( 10 ) according to claim 1 , wherein the current limiting device ( 12 ) comprises a reference voltage source (U Ref ) which is designed to provide a predetermined reference voltage; and the current limiting device ( 12 ) is designed to compare a further voltage signal to the reference voltage provided by the reference voltage source (U Ref ) and to adjust the electric current through the current measuring device ( 11 ) on the basis of the comparison.

5 . The current detection device ( 10 ) according to claim 4 , wherein the current limiting device ( 12 ) comprises a transistor (T 5 ) having a control connection and said current limiting device ( 12 ) is designed to provide, at the control connection of the transistor (T 5 ), a control signal based on the comparison between provided reference voltage and the further voltage signal.

6 . A circuit arrangement ( 1 ) for providing an electric current (I E ), the circuit arrangement comprising:
a current control device ( 20 ) which is designed to provide an electric current (I E ) in a power path and to provide an electric measuring current (I Sense ) in a measuring path which corresponds to the electric current (I E ) provided in the power path; and a current detection device ( 10 ) according to claim 1 .

7 . The circuit arrangement ( 1 ) according to claim 6 , wherein the current control device ( 20 ) comprises a bipolar transistor having an insulated gate, IGBT.

8 . A method ( 100 ) for sensing an electric current (I Sense ) in a measuring path, which conducts an electric current that corresponds to an electric current (I E ) in a power path, comprising the following steps:
providing ( 110 ) a current measuring device ( 11 ); sensing ( 120 ) an electric current through the current measuring device ( 11 ) provided; emitting ( 130 ) an output signal at the current measuring device ( 11 ) as a function of the sensed electric current; and limiting ( 140 ) the electric current through the current measuring device ( 11 ) to a predetermined maximum limit value.

9 . The method ( 100 ) according to claim 8 , further comprising the steps:
providing a predetermined reference voltage; comparing the emitted output signal to the reference voltage provided; wherein step ( 140 ) for limiting the electric current adjusts the current in accordance with the comparison of the reference voltage provided to a voltage value.

Assignees

• Bosch Gmbh Robert

Inventors

• Sievert Holger
• Butzmann Stefan

Classifications

• G01R19/0092

  Measuring current only · CPC title

• G01R15/146

  Measuring arrangements for current not covered by other subgroups of G01R15/14, e.g. using current dividers, shunts, or measuring a voltage drop (if no voltage isolation is involved G01R1/203 or G01R19/0092) · CPC title

• G05F1/573 Primary

  with overcurrent detector · CPC title