Patent ID: 11942778
Assignee: VITESCO TECHNOLOGIES GMBH
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC G  H | IPC H

Claim 4:
5. A method for supplying power to an inductive load including
an H-bridge switching structure coupled to a positive power supply and an electrical ground, the H-bridge switching structure including a first switch, a second switch, a third switch, and a fourth switch that are distributed over two branches of the H-bridge, the switching structure being configured to drive a current in the inductive load through a first control output and a second control output, and
an anomaly detector configured to generate at least one item of anomaly detection information about detection of an anomaly at the H-bridge switching structure, the anomaly detector including
a first voltage generator controlled and configured to deliver a first reference voltage,
a second voltage generator controlled and configured to deliver a second reference voltage, said first and second voltage generators being coupled respectively to the first control output and the second control output, the value of the first reference voltage being greater than the value of the second reference voltage,
a first current measuring device configured to measure a current at the output of the first voltage generator,
a second current measuring device configured to measure a current at an output of the second voltage generator,
a third current measuring device coupled between the first switch and the first control output,
a fourth current measuring device coupled between the second switch and the first control output,
a fifth current measuring device coupled between the third switch and the second control output,
a sixth current measuring device coupled between the fourth switch and the second control output,
the current measuring devices being configured to respectively measure the currents flowing through said switches,
a seventh voltage measuring device coupled to the first control output, and
an eighth voltage measuring device coupled to the second control output,
said seventh and eighth voltage measuring devices being configured to measure voltages on the control outputs,, the method comprising:
e1) positioning the first, second, third, and fourth switches of the H bridge switching structure in an off state;
e2) verifying and awaiting the off state of all of the first, second, third, and fourth switches;
e3) sequentially measuring a current flowing through each of the first, second, third, and fourth switches, and
(i) when there is no current flowing through all of the first, second, third, and fourth switches, then moving to step e11),
(ii) when there is at least one current flowing through at least one of the first, second, third, and fourth switches, awaiting a first determined duration before performing a new measurement of the current flowing through each of the first, second, third, and fourth switches and then, when there is at least one current in at least one of the first, second, third, and fourth switches, then identifying whether one of the first and third switches coupled to the positive power supply is being flowed through by said measured current,
(a) when one of said first and third switches is being flowed through by said current, moving to step e8), and
(b) when neither of said two switches is being flowed through by a current, then identifying whether one of the two switches coupled to electrical ground is being flowed through by said measured current, and when one of said two switches is being flowed through by said current, moving to step e10);

e8) confirming the presence of a short circuit to a voltage level higher than the battery anomaly at at least one of the two high-side switches;
e10) confirming the presence of a short circuit to a voltage level lower than ground anomaly at at least one of the two low-side switches;
e11) detecting the presence of an electromotive force between the first control output and the second control output by measuring the voltages on the first control output and the second control output, and
(i) when the measured voltages are equal, moving to step e12), and
(ii) when the measured voltages are different, then
recording the difference between the first control output and the second control output corresponding to the electromotive force to control the connected load,
awaiting a second determined duration before subsequently measuring the voltages on the first control output and the second control output, and
when the subsequently measured voltages have equal values, then moving to step e12), otherwise implementing an alert and stopping the execution of the method;

e12) coupling a first voltage generator and a second voltage generator to said control outputs, and then respectively applying a first voltage and a second voltage;
e14) measuring the voltages on the first control output and the second control output, and
(i) when the measured voltage variations over time are outside a first measurement range, moving to step e16), and
(ii) when the measured voltage variations are within the first measurement range, and then moving to step e20);

e16) awaiting a third determined time before measuring the voltages on the first control output and the second control output again, and
(i) when the measured voltage variations are again outside the first measurement range, then declaring a frequency interference anomaly, and
(ii) when the measured voltage variations are within the first measurement range, moving to step e20);

e20) measuring the currents flowing through the first control output and the second control output, and
(i) when the difference between the two measured currents is within a second measurement range, then stopping the anomaly test and declaring no short circuit or open circuit anomaly, and
(ii) when the difference between the two measured currents is not within the second measurement range, then moving to step e23);

e23) measuring the voltages of the two outputs, and
(i) when the voltage measured on the first control output is different from the voltage measured on the second control output, then the detected anomaly is determined to be an open load anomaly, and stopping the execution of the method, and
(ii) when the voltage measured on the first control output is not different from the voltage measured on the second control output, moving to step e25); and

e25) measuring the voltages on the first control output and the second control output, and
(i) when the measured voltages are greater than the voltages generated by the voltage generators connected to the outputs, then generating an alert regarding the presence of a short circuit to the positive voltage anomaly, and
(ii) when the measured voltages are lower than the voltages generated by the voltage generators connected to the outputs, then generating an alert regarding the presence of a short circuit to electrical ground anomaly.