Apparatus for tripping a circuit breaker for vehicles

Patent metadata

Field	Value
Publication number	US-11309697-B2
Application number	US-201615177988-A
Country	US
Kind code	B2
Filing date	Jun 9, 2016
Priority date	Dec 12, 2013
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

An apparatus is provided for protecting high-voltage electrical connections, in particular in vehicles. A fuse for interrupting a line includes a conduction coil, which is designed to have a conduction current on the line flowing through the conduction coil and to thereby generate a magnetic field. Furthermore, the includes a control coil, which is magnetically coupled to the conduction coil, and a circuit breaker, which is designed to interrupt the line depending on a field intensity of the magnetic field. In addition, the fuse includes a control unit, which is designed to determine a control current through the control coil in order to vary the field intensity of the magnetic field, and thus to cause or suppress an interruption of the line by way of the circuit breaker.

First claim

What is claimed is:

1. A fuse for interrupting a line, the fuse comprising:
a line coil that is configured to carry a line current on the line and to thereby generate a magnetic field;
a control coil that is magnetically but not electrically coupled to the line coil;
a circuit breaker, which is magnetically coupled to the control coil and the line coil and that is configured to be opened by the magnetic field to interrupt the line based on a field strength of the magnetic field; and
a control unit that controls a control current through the control coil in order to alter the field strength of the magnetic field, so as to:
(a) prevent the circuit breaker from opening to interrupt the line by compensating for changes in the magnetic field of the line coil caused by the line current, and
(b) cause the circuit breaker to open to interrupt the line by ceasing to compensate for changes in the magnetic field of the line coil caused by the line current,

wherein the circuit breaker is not controlled via an electrical signal received by the circuit breaker from the control unit.

2. The fuse according to claim 1 , wherein:
the fuse comprises a device for measuring the field strength of the magnetic field; and
the control unit is set up to determine the control current based on the measured field strength of the magnetic field.

3. The fuse according to claim 2 , wherein the control unit is further set up to:
compare a signal derived from the control current with a tripping current threshold value;
determine the control current such that the magnetic field generated by the line coil is attenuated if the derived signal is smaller than the tripping current threshold value; and/or
determine the control current such that the magnetic field generated by the line coil is boosted if the derived signal is larger than the tripping current threshold value.

4. The fuse according to claim 3 , wherein the control unit is further set up to:
establish whether the signal derived from the control current is at or above the tripping current threshold value for at least one predefined period; and
determine the control current such that the magnetic field generated by the line coil is boosted if the derived signal is at or above the tripping current threshold value for at least the predefined period.

5. The fuse according to claim 4 , wherein the control unit is further set up to determine the control current such that the field strength is lower than a predefined field strength threshold value if the derived signal is smaller than the tripping current threshold value.

6. The fuse according to claim 3 , wherein the control unit is further set up to determine the control current such that the field strength is lower than a predefined field strength threshold value if the derived signal is smaller than the tripping current threshold value.

7. The fuse according to claim 1 , wherein the line coil comprises a smaller number of turns than the control coil.

8. The fuse according to claim 1 , wherein the fuse comprises a resetting coil that is set up to close the circuit breaker, by building up an additional magnetic field, in order to suspend interruption of the line.

9. The fuse according to claim 1 , wherein:
the fuse is designed such that the magnetic field generated by the line current causes interruption of the line by the circuit breaker if the line current reaches or exceeds a default threshold value; and
the default threshold value is lower than a predefined feasible operating current for a component that is supplied with electric current via the line.

10. The fuse according to claim 9 , wherein:
the component has a typical operating current that is smaller than the predefined feasible operating current of the component;
the default threshold value is lower than the typical operating current; and
the control unit is set up to determine the control current such that the circuit breaker interrupts the line at a line current that is higher than the typical operating current and is smaller than the predefined feasible operating current.

11. An apparatus for identifying a fault current through a load, the apparatus comprising:
a first fuse on a line that leads to the load, wherein the first fuse is configured to determine a first control current;
a second fuse on a line that leads away from the load, wherein the second fuse is configured to determine a second control current; and
a comparison unit that is configured to compare the first and second control currents and to take the comparison as a basis for identifying a fault current,
wherein each of the first and second fuses comprises:
a line coil that is configured to carry a line current on the line and to thereby generate a magnetic field;
a control coil that is magnetically but not electrically coupled the line coil;
a circuit breaker, which is magnetically coupled to the control coil and the line coil and that is configured to be opened by the magnetic field to interrupt the line based on a field strength of the magnetic field; and
a control unit that is configured to control the control current through the control coil in order to alter the field strength of the magnetic field, so as to:
(a) prevent the circuit breaker from opening to interrupt the line by compensating for changes in the magnetic field of the line coil caused by the line current, and
(b) cause the circuit breaker to open to interrupt the line by ceasing to compensate for changes in the magnetic field of the line coil caused by the line current,

wherein the circuit breaker is not controlled via an electrical signal received by the circuit breaker from the control unit.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Krammer Josef

Classifications

• H01H47/007 Primary

  with galvanic isolation between controlling and controlled circuit, e.g. transformer relay · CPC title

• H01H71/125

  characterised by sensing elements, e.g. current transformers (for differential protection H01H83/144) · CPC title

• H02H1/0007 Primary

  concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445) · CPC title

• H02H3/087

  for DC applications · CPC title