Diagnostic method for an on-board charger device

Abstract

A computer-implemented method for determining at least two short-circuit states within an on-board vehicle charger (1) intended to be connected to an alternating voltage and comprising a measuring resistor (17). The determination of the short-circuit states is performed by comparing a reference measurement of an electrical quantity with at least one measurement of that same quantity for each short-circuit state to be determined. The method is characterized in that all measurements of the electrical quantity are associated with the measuring resistor (17). Abstract figure: Fig. 1

Description

Title of the invention: Method for diagnosing an on-board charger device

[0001] The present application refers to a method for diagnosing an on-board charger device for a vehicle. Such a charger enables the electrical power supply of an electrical energy storage unit of a vehicle. The electrical energy storage unit is for example a battery, which may have a nominal voltage greater than 60V, for example greater than 300V, 400V, 800V or even 1000V.

[0002] Such a component comprises in a known example: - an inverter / rectifier receiving as input an alternating voltage from a charging terminal and supplying as output a direct voltage, and - a DC / DC converter located downstream of the inverter / rectifier and connected to the electrical energy storage unit.

[0003] Such an inverter / rectifier and such a DC / DC converter implement a plurality of controllable electronic switches such as MOSFET transistors or IGBTs. A failure in one of these switches can lead to the existence of a short circuit at the terminals of this controllable electronic switch. There is a risk of tripping a charging terminal connected to the on-board charger device following such a fault. Furthermore, if the on-board charger device is not put into a disabled state, there is a risk that the next time the on-board charger device is connected to another charging terminal, this other terminal will also trip. To avoid such a risk, it is known to have fuses between the inverter / rectifier and the connector allowing the connection of the on-board charger device to the charging terminal. The use of fuses generates additional cost and can generate additional space requirements.Furthermore, the use of fuses generates losses and heating.

[0004] There is a need to further improve such components by overcoming all or part of the above drawbacks.

[0005] The invention aims to meet this need and achieves this, according to one of its aspects, using a computer-implemented method for determining at least two short-circuit states within an on-board vehicle charger device, said device comprising a measuring resistor, the determination of the short-circuit states being made from the comparison of a reference measurement of an electrical quantity and at least one measurement of this same electrical quantity per short-circuit state to be determined, the method being characterized in that all the measurements of this same electrical quantity are associated with the measuring resistance.

[0006] This method makes it possible to determine short-circuit conditions in the on-board charger device before connecting said device to the charging terminal, which can make it possible to completely eliminate the presence of fuses in said device.

[0007] This method also has the advantage of being able to carry out the various short-circuit state determinations for numerous elements of the on-board charger device thanks to the simple presence of this single measuring resistor. This solution is therefore advantageous because it requires a reduced number of components in order to determine the short-circuit states.

[0008] The on-board charger device may comprise a controllable switch arranged in parallel with the measuring resistor, the method then comprises:

[0009] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a first reference measurement;

[0010] - the control of said switch, controlled to be in the open position;

[0011] - the measurement of the electrical quantity associated with the measuring resistance;

[0012] - determining a first short-circuit state of said switch from the detection of an absence of difference between the previous measurement and the reference measurement.

[0013] Closing the switch in parallel with the measuring resistor makes it possible to limit the impact of the presence of said resistor during normal operation of the on-board charger device. The presence of this switch then requires a first series of steps in order to determine whether it is in a short-circuit state before carrying out the other steps of the method.

[0014] A timing step can be carried out after the step of determining a first short-circuit state of the switch arranged in parallel with the measuring resistor, this timing being able to be equal to 600 ms.

[0015] The on-board charger device may comprise a switching arm comprising two switches controllable on either side of a midpoint intended to be connected to the neutral of an alternating voltage, the first and second switches being intended to be connected to a first and a second direct potential respectively, the method then comprising:

[0016] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure;

[0017] - the control of the two switches of said arm, one being controlled to be in position open, the other to be in the closed position;

[0018] - the measurement of the electrical quantity associated with the measuring resistance;

[0019] - determining a short-circuit state of the controlled switch to be in open position from the detection of a difference between the previous measurement and the reference measurement;

[0020] - the control of the two switches, the switch previously in the open position being piloted to be in the closed position and vice versa;

[0021] - the measurement of the electrical quantity associated with the measuring resistance;

[0022] - determining a short-circuit state of the controlled switch to be in open position from the detection of a difference between the previous measurement and the reference measurement.

[0023] The device may comprise an additional controllable switch arranged between the midpoint intended to be connected to the neutral of the alternating voltage, and the midpoint of a branch comprising two capacitors arranged on either side of this midpoint, the first and second capacitors being intended to be connected to the first and second direct potential respectively. The steps of controlling the switches of the branch comprising the midpoint intended to be connected to the neutral of the alternating voltage may then comprise controlling said additional switch to be in the open position. The steps of determining a short-circuit state of the switches of said switching arm then make it possible to determine a short-circuit state of the additional switch.

[0024] This additional switch can correspond to a pre-charge relay, allowing the capacitors of the branch described previously to be charged.

[0025] The device may comprise a switching arm, comprising two controllable switches arranged on either side of a midpoint intended to be connected to a phase of an alternating voltage, the first and second switches being intended to be connected to the first and second direct potential respectively, the method then comprises:

[0026] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure

[0027] - the control of the two switches of said arm, one being controlled to be in position open, the other to be in the closed position;

[0028] - the measurement of the electrical quantity associated with the measuring resistance;

[0029] - determining a short-circuit state of the controlled switch to be in open position from the detection of a difference between the previous measurement and the reference measurement;

[0030] - the control of the two switches, the switch previously in the open position being piloted to be in the closed position and vice versa;

[0031] - the measurement of the electrical quantity associated with the measuring resistance;

[0032] - determining a short-circuit state of the controlled switch to be in open position from the detection of a difference between the previous measurement and the reference measurement.

[0033] The device may comprise at least two switching arms, comprising each two controllable switches arranged on either side of a midpoint intended to be connected to a respective phase of the alternating voltage, the first and second switches of each arm being intended to be connected to the first and second direct potential respectively. The steps of controlling the switches of the switching arm comprising a midpoint being intended to be connected to a phase of the alternating voltage as described previously can then be carried out simultaneously for all said switching arms. Consequently, the steps of determining a short-circuit state of the switch of the switching arm comprising a midpoint being intended to be connected to a phase of the alternating voltage controlled to be in the open position as described previously make it possible to determine a short-circuit state for all said switching arms.

[0034] As a variant, the steps of controlling the switches of a switching arm comprising a midpoint intended to be connected to a phase of the alternating voltage, of measuring, and of determining a short-circuit state of a switch controlled to be in the open position of said switching arm as described previously are repeated successively for each switching arm comprising a midpoint being intended to be connected to a respective phase of the alternating voltage.

[0035] The device may comprise at least one switching arm comprising two controllable switches arranged on either side of a midpoint intended to be connected to a respective phase of an alternating voltage, the first and second switches being intended to be connected to the first and second direct potential respectively, and a switching arm, comprising two controllable switches arranged on either side of a midpoint intended to be connected to the neutral of the alternating voltage, the first switch and the second switch being intended to be connected to the first and second direct potential respectively, the method then comprises:

[0036] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure;

[0037] - the control of the two switches of the at least one switching arm comprising a midpoint intended to be connected to a respective phase of the alternating voltage, the switch intended to be connected to the first direct potential being controlled to be in the closed position, the switch intended to be connected to the second direct potential being controlled to be in the open position;

[0038] - the control of the two switches of the switching arm comprising a point medium intended to be connected to the neutral of the alternating voltage, the switch intended to be connected to the first continuous potential being controlled to be in the open position, that intended to be connected to the second continuous potential being controlled to be in the closed position;

[0039] - the measurement of the electrical quantity associated with the measuring resistance;

[0040] - determining a short-circuit state between the at least one switching arm comprising a midpoint intended to be connected to a respective phase of the alternating voltage and the switching arm comprising a midpoint intended to be connected to the neutral of the alternating voltage from the detection of a difference between the previous measurement and the reference measurement.

[0041] The device may comprise at least two switching arms, each comprising two switches arranged on either side of a midpoint intended to be connected to a respective phase of an alternating voltage, the first switch and the second switch being intended to be connected to the first and second direct potential respectively, the method then comprises:

[0042] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure;

[0043] - the control of the switches of two of said switching arms, the switch intended to be connected to the first continuous potential of the first arm being controlled to be in the closed position, the switch intended to be connected to the second continuous potential of the second arm being controlled to be in the closed position, the other switches of said arms being controlled to be in the open position;

[0044] - the measurement of the electrical quantity associated with the measuring resistance;

[0045] - determining a short-circuit state between the two switching arms at from the detection of a difference between the previous measurement and the reference measurement.

[0046] The steps of controlling the switches of two of the switching arms comprising a midpoint intended to be connected to a respective phase of the alternating voltage, of measuring and determining a short-circuit state between the two switching arms as described previously can be carried out successively for each pair of switching arms comprising a midpoint intended to be connected to a respective phase of the alternating voltage.

[0047] The order of the steps for determining the short-circuit state, starting with the switch in parallel with the measuring resistor, then with the switching arm comprising a midpoint intended to be connected to the neutral of the alternating voltage, then with the at least one switching arm comprising a midpoint intended to be connected to a respective phase of the alternating voltage, corresponds to an advantageous embodiment of the present method, making it possible to progressively pass through the switches from the measuring resistor to the alternating voltage source and from ensure that the device is suitable for connection to the AC voltage source.

[0048] The device may comprise at least two switching arms, each comprising two switches controllable on either side of a midpoint intended to be connected to a primary winding of a transformer of a DC / DC voltage converter, the first and second switches of each arm being intended to be connected to a first and a second DC potential respectively, the method then comprises:

[0049] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure;

[0050] - the control of the switches of said switching arms, the switches intended to be connected to the first continuous potential being controlled to be in the closed position, the switches intended to be connected to the second continuous potential being controlled to be in the open position;

[0051] - the measurement of the electrical quantity associated with the measuring resistance;

[0052] - determining a short-circuit state of the controlled switches to be in open position from the detection of a difference between the previous measurement and the reference measurement;

[0053] - the control of the switches of said switching arms, the pre-switches previously in the open position being piloted to be in the closed position, and vice versa;

[0054] - the measurement of the electrical quantity associated with the measuring resistance;

[0055] - determining a short-circuit state of the controlled switches to be in open position from the detection of a difference between the previous measurement and the reference measurement.

[0056] Similarly, the method may comprise:

[0057] - the measurement of the electrical quantity associated with the measuring resistance in order to establish a reference measure;

[0058] - the control of the switches of two of the switching arms comprising a point medium intended to be connected to a primary winding of a transformer of a DC / DC voltage converter, the switch intended to be connected to the first DC potential of the first arm being controlled to be in the closed position, the switch intended to be connected to the second DC potential of the second arm being controlled to be in the closed position, the other switches being controlled to be in the open position;

[0059] - the measurement of the electrical quantity associated with the measuring resistance;

[0060] - determining a short-circuit state between said two switching arms at from the detection of a difference between the previous measurement and the reference measurement.

[0061] The steps of controlling the switches of two of the switching arms comprising a midpoint intended to be connected to a primary winding of a transformer of a DC / DC voltage converter, of measuring and determining a short-circuit state between said two switching arms as described previously can be carried out successively for each pair of switching arms comprising a midpoint intended to be connected to a primary winding of a transformer of a DC / DC voltage converter.

[0062] Optionally, the steps of measuring the electrical quantity associated with the measurement resistance in order to establish a reference measurement may be omitted beyond the first step of measuring the electrical quantity in order to establish a reference measurement. In this case, each step of determining a short-circuit state makes a comparison between the first reference measurement and the measurement made previously to this said step of determining a short-circuit state.

[0063] The method may comprise a final step if no short circuit condition has been determined in one of its steps of determining a short circuit condition, the method returning a signal authorizing the connection of the on-board charger device to the alternating current source.

[0064] In all of the above, the method may return a signal prohibiting the connection of the on-board charger device to an AC voltage source if a short-circuit condition is determined during a step of said method.

[0065] In all of the above, a delay step can be carried out between the switch control steps and the measurement steps, this delay being able to be 1 ms.

[0066] In all of the above, the electrical quantity can be the voltage across the measuring resistor.

[0067] Alternatively, the electrical quantity may be the current flowing through the measuring resistor.

[0068] The invention also relates, according to one of its aspects, to an on-board charger device for a vehicle comprising:

[0069] - a connector intended to be connected to an electrical network supplying a voltage three-phase alternative,

[0070] - an inverter / rectifier, comprising three switching arms mounted in parallel, each switching arm comprising two switches arranged on either side of a midpoint, this midpoint being intended to be connected to a respective phase of the alternating voltage,

[0071] - a fourth switching arm mounted in parallel with the switching arms of the inverter / rectifier, this fourth switching arm comprising two switches arranged on either side of a fourth midpoint intended to be connected to the neutral of the alternating voltage, and

[0072] - a branch mounted in parallel with said switching arms, comprising two capacitors arranged on either side of a fifth midpoint, the branch and the switching arms being mounted between two terminals with continuous potential,

[0073] - a switch mounted in series between the fourth and fifth midpoint,

[0074] - a DC / DC voltage converter connected in cascade with the fourth arm of switching and the branch comprising the two capacitors, comprising at least two switching arms, each having two switches arranged on either side of a midpoint intended to be connected to a primary winding of a transformer of said converter,

[0075] - a measuring resistor, mounted in parallel with a switch; and

[0076] - a control unit for said on-board vehicle charger, comprising the means to implement the method of determining at least two short-circuit states as described previously.

[0077] The measuring resistor can be connected in series with the capacitor arranged between the fifth midpoint and one of the terminals with continuous potential being ground.

[0078] This position of the measuring resistor allows it to be associated with a fixed electrical potential, namely ground.

[0079] Alternatively, the measuring resistor can be connected in series with the capacitor arranged between the fifth midpoint and one of the terminals with continuous potential which is not ground.

[0080] Alternatively, the measuring resistor may be mounted at one of the terminals with continuous potential which is not ground, between the capacitor arranged on one side of the fifth midpoint, and the switch arranged on one side of the fourth midpoint.

[0081] In all of the above, the measuring resistor may be a simple resistor, i.e. an impedance whose resistance value remains constant. Alternatively, this measuring resistor may be a thermistor. This is, for example, a thermistor with a positive temperature coefficient, also called a “PTC” in English. The invention is not limited to a resistor, the use of an inductor being conceivable.

[0082] The invention also relates, according to one of its aspects, to a computer program product, comprising instructions which cause the control unit of the on-board charger device as described previously to carry out the steps of the method for determining at least two short-circuit states as described.

[0083] The invention also relates, according to one of its aspects, to a computer-readable medium, on which the computer program as described above is recorded.

[0084] The invention may be better understood by reading the following description. non-limiting examples of its implementation:

[0085] - [Fig.l] schematically represents the electrical circuit of a device of on-board charger 1 for charging an electrical energy storage unit.

[0086] - [Fig.2] is a diagram representing the different defects whose existence can be detected in the component of [Fig.l], and

[0087] - [Fig.3] representing the steps carried out during the detection of the existence of the defects of [Fig.2] according to one embodiment of the invention.

[0088] [Fig.l] shows an example of an electrical circuit 2 of an on-board charger device 1 for charging an electrical energy storage unit, also called a “charger”. The electrical energy storage unit is here a battery used for the electrical power supply of an electric vehicle propulsion machine. This battery has, for example, a nominal voltage greater than 60V, in particular 300V, in particular 400V, in particular 800V, or even 1000V.

[0089] The electrical network is for example a three-phase network carrying a voltage at a first frequency which is 50Hz or 60Hz and whose effective value is 230V or 240V. The electrical network is connected to the electrical circuit 2 via a connector 3 shown schematically in [Fig.l].

[0090] The electrical circuit 2 comprises, in this example:

[0091] - an inverter / rectifier 6, comprising three switching arms 7 mounted in parallel, each switching arm 7 comprising two switches 8 arranged on either side of a midpoint 9 intended to be connected to a respective phase of the alternating voltage,

[0092] - a fourth switching arm 10 mounted in parallel with the switching arms 7, this fourth switching arm 10 comprising two switches 11 arranged on either side of a fourth midpoint 12 intended to be connected to the neutral of the electrical network, and

[0093] - a branch 13 mounted in parallel with said switching arms 7 and 10, comprising two capacitors 14 arranged on either side of a fifth midpoint 15, and a measuring resistor 17, mounted in series with one of the capacitors 14. The measuring resistor 17 is here a thermistor with a positive temperature coefficient, also called “PTC” in English.

[0094] All the switches 8 are here MOSFET transistors and the switches 11 are IGBT transistors.

[0095] It can be seen that branch 13 and switching arms 7 and 10 are mounted between two terminals with continuous potential. It can also be seen in the example considered:

[0096] - that the measuring resistor 17 is connected in series between the ground and the capacitor 14 arranged between the fifth midpoint 15 and the mass, and

[0097] - that a first switch 20 is mounted in parallel with this measuring resistor 17.

[0098] The fourth midpoint 12 is also connected to the fifth midpoint 15 via a second switch 21, which may correspond to a pre-charging relay for the capacitors arranged on either side of the midpoint 15.

[0099] The first switch 20 and the second switch 21 are here electrotechnical relays. Alternatively, other examples are possible, for example the use of static relays based on optical couplers and / or MOSFET transistors and / or IGBT transistors.

[0100] Still in the example of [Fig.l], another capacitor 18 is mounted in parallel with branch 13.

[0101] The electrical circuit 2 also comprises in the example of [Fig.l] a DC / DC converter 25. This DC / DC converter 25 here comprises in a known manner two DC / AC converters 28 and 29. It can be seen in [Fig.l] that the DC / AC converter 28 is here reversible, using two switching arms 31 each comprising two bidirectional switches 32, 34 arranged on either side of two midpoints 33, 35, mounted between two terminals with continuous potential, one being ground, and said switches being MOSFET transistors, whereas the DC / AC converter 29 is unidirectional, being here a diode rectifier. A galvanic isolation transformer 30 is arranged between these two DC / AC converters 28 and 29. This DC / DC converter is for example resonant, being of the LLC or CLLC type, among others.

[0102] As shown in [Fig.l], an alternating current filtering stage 35 may be provided, this filtering stage 35 being here arranged in series between the connector 3 and the inverter / rectifier 6. This filtering stage 35 allows in particular when the alternating voltage is polyphase, a filtering of the common mode current and / or a filtering of the differential current. As shown, relays may be present, to allow switching from a three-phase mode to a single-phase mode, and vice versa.

[0103] If necessary, and as shown in [Fig.l], another direct current filtering stage 36 may be present, then being arranged in series between the DC / DC converter 25 and the electrical energy storage unit, as shown in [Fig.l].

[0104] Component 1 is advantageously without a fuse.

[0105] The component 1 comprises a control unit 40 whose role will be described below. This control unit 40 is for example produced using several modules, as can be seen in [Fig.l]. This control unit 40 comprises for example microcontrollers and / or integrated circuits such as ASICs or FPGAs.

[0106] In the example of [Fig.2], a low voltage is available during a state 100 at the terminals of the switching arms 7 and 10. This voltage, not obtained via the connector 3, is obtained from the power supply of the control unit 40 and has a value between 12V and 24V, for example 18V. The voltage across the resistor measurement 17 can be measured by the control unit several times and these measurements can make it possible to determine:

[0107] - according to 101 if the first switch 20 is in a short-circuit state,

[0108] - according to 102 if the second switch 21 is in a short-circuit state and if one of the in switches 11 of the fourth switching arm 10 are short-circuited,

[0109] - according to 103 if one of the switches 8 of one of the switching arms 7 of inverter / rectifier 6 is in short circuit condition,

[0110] - according to 104 if there is a short circuit between a phase of the alternating voltage and the neutral,

[0111] - according to 105 if there is a short circuit between two of the three phases of the voltage al alternative,

[0112] - according to 106 if one of the switches 32, 34 of one of the switching arms 31 of the DC / DC voltage converter 25 is in short-circuit condition, and

[0113] - according to 107 if there is a short circuit between the switching arms 31 of the DC / DC voltage converter 25.

[0114] It is then possible, according to 108, to establish a diagnosis of the suitability of the component 1 to be connected to the electrical network.

[0115] The different steps for establishing this diagnosis will now be described with reference to [Fig. 3]. To carry out these steps, the control unit 40 carries out, in the example considered, a sequence of measurements of the voltage across the measuring resistor 17 and, using these measurements, it determines the existence or not of several of these faults, a measurement being associated with the determination of one or more of said faults.

[0116] The measurement is for example compared by the control unit 40 to a reference value and, depending on the result of this comparison, the control unit 40 determines whether the fault exists or not.

[0117] In the example of [Fig. 3], according to an initialization step 200, the voltage across the measuring resistor 17 is measured to obtain, according to a step 201, a first reference value, without applying an external voltage. During step 202, the control unit 40 controls the opening of the first switch 20 arranged in parallel with the measuring resistor 17. During step 203, the control device controls a switch not shown in [Fig. 1] so as to supply a DC voltage coming from the power supply of the control unit 40 to the terminals of the branch 13. This DC voltage here has a value of 18V. A time delay, for example of 1ms, is applied according to step 204.

[0118] During step 205, the voltage across the measuring resistor 17 is measured. During step 206, the control unit determines whether the voltage value measured during step 205 is the same or not as that measured during step 201. In case equality, the control unit deduces during step 207 that the first switch 20 is in a short-circuit state and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of non-equality, the control unit deduces during step 208 that the first switch 20 is not in a short-circuit state. Steps 207 and 208 complete the detection by the control unit 40 of a short-circuit state of the first switch 20. When step 208 is carried out, the control unit can proceed to the test of a short-circuit state of the second switch 21 according to steps 210 to 217.

[0119] During step 210, a time delay, for example of 600 ms is applied. During step 211 a measurement of the voltage across the measuring resistor 17 is carried out to establish a reference measurement. During step 212, the control unit 40 controls the closing of the switch 11 arranged between the ground and the fourth midpoint 12, the opening of the switch 11 arranged between the terminal at the positive potential and the fourth midpoint 12 and the opening of the switch 21 arranged between the midpoint 12 of the switching arm 10 and the midpoint 15. During step 213, a time delay, for example of 1 ms is applied. In step 214, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. In step 215, the control unit 40 determines whether the voltage value measured in step 214 is the same or not as that measured in step 211.In the event of non-equality, the control unit deduces during step 216 that the switch 11 arranged between the fourth midpoint 12 and the terminal at the positive DC potential is in a short-circuit state or that the second switch 21 is in a short-circuit state and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 217 that the second switch 21 is not in a short-circuit state. Steps 216 and 217 complete the detection by the control unit 40 of a short-circuit state of the second switch 21. When step 217 is carried out, the control unit can proceed to the test of a short-circuit state of the switch 11 arranged between the ground and the fourth midpoint 12 according to steps 220 to 226.

[0120] In step 220, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 221, the control unit 40 commands the closing of the switch 11 arranged between the terminal at the positive DC potential and the fourth midpoint 12 and the opening of the switch 11 arranged between the ground and the fourth midpoint 12. In step 222, a time delay, for example of 1 ms, is applied. In step 223, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 224, the control unit 40 determines whether the voltage value measured in step 224 is the same or not as that measured in step 221. In the event of non-equality, the control unit deduces during step 225 that the switch 11 arranged between the ground and the fourth midpoint 12 is in a short-circuit state and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 226 that the switch 11 arranged between the ground and the fourth midpoint 12 is not in a short-circuit state. Steps 225 and 226 complete the detection by the control unit 40 of a short-circuit state of the switch 11 arranged between ground and the fourth midpoint 12. When step 226 is carried out, the control unit can proceed to test a short-circuit state of the switches 8 of the inverter / rectifier 6 arranged between a midpoint 9 and one of the terminals with direct potential according to steps 230 to 236.

[0121] In step 230, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 231, the control unit 40 commands the closing of all the switches 8 arranged between a midpoint 9 and ground and the opening of all the switches 8 arranged between a midpoint 9 and the positive DC potential. In step 232, a time delay, for example of 1 ms, is applied. In step 233, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 234, the control unit 40 determines whether the voltage value measured in step 233 is the same or not as that measured in step 230.In the event of non-equality, the control unit deduces during step 235 that one of the switches 8 arranged between the positive DC potential and a midpoint 9 is in a short-circuit state and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 236 that none of the switches 8 arranged between the positive DC potential and a midpoint 9 is in a short-circuit state. Steps 235 and 236 complete the detection by the control unit 40 of a short-circuit state of one of the switches 8 arranged between a midpoint and the positive DC potential. When step 236 is carried out, the control unit can proceed to test a short-circuit state of the switches 8 of the inverter / rectifier 6 arranged between a midpoint 9 and the other of the terminals with continuous potential, here the ground, according to steps 240 to 245.

[0122] In step 240, a measurement of the voltage across the measuring resistor 17 is carried out to establish a reference measurement. In step 241, the control unit 40 commands the closing of all the switches 8 arranged between a midpoint 9 and the positive DC potential and the opening of all the switches 8 arranged between a midpoint 9 and ground. In step 242, a time delay, for example of 1 ms, is applied. In step 243, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. step 244, the control unit 40 determines whether the voltage value that has just been measured is the same or not as that measured during step 240. In the event of non-equality, the control unit deduces during step 245 that one of the switches 8 arranged between ground and a midpoint 9 is in a short-circuit state and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 246 that none of the switches 8 arranged between ground and a midpoint 9 is in a short-circuit state. Steps 245 and 246 complete the detection by the control unit 40 of a short-circuit state of one of the switches 8 arranged between a midpoint and ground. When step 246 is performed, the control unit 40 can proceed to test for the existence of a short circuit between a phase of the alternating voltage and the neutral according to steps 250 to 256.

[0123] In step 250, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 251, the control unit 40 commands the closing of all the switches 8 arranged between a midpoint 9 and the positive DC potential, the opening of all the switches 8 arranged between a midpoint 9 and ground and the opening of the switch 11 arranged between the fourth midpoint 12 and ground. In step 252, a time delay, for example of 1 ms is applied. In step 253, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 254, the control unit 40 determines whether the voltage value that has just been measured is the same or not as that measured in step 250.In the event of non-equality, the control unit deduces in step 255 that there is a short circuit between one of the phases and the neutral and it sends a message stating that it is impossible to connect the connector 3 to the electrical network. In the event of equality, the control unit deduces in step 256 that no phase is short-circuited with the neutral. Steps 255 and 256 complete the detection by the control unit 40 of a short circuit between a phase and the neutral. When step 255 is carried out, the control unit 40 can proceed to test for the existence of a short circuit between two phases of the alternating voltage according to steps 260 to 266, 270 to 276 and 280 to 286.Steps 260 to 266 relate to the existence of a short circuit between the first phase and the second phase of the alternating voltage, steps 270 to 276 relate to the existence of a short circuit between the first phase and the third phase of the alternating voltage, and steps 280 to 286 relate to the existence of a short circuit between the second phase and the third phase of the alternating voltage.

[0124] In step 260, a measurement of the voltage across the measuring resistor 17 is carried out to establish a reference measurement. In step 261, the control unit 40 commands the closing of the switch 8 of the switching arm 7 for the first phase arranged between the midpoint 9 of this arm 7 and the terminal at the potential positive DC, and the closing of the switch 8 of the switching arm 7 for the second phase arranged between the midpoint 9 of this arm 7 and the ground. All the other switches of the other switching arms 7 are controlled to be in the open position. During step 262, a time delay, for example of 1 ms is applied. During step 263, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. During step 264, the control unit 40 determines whether the voltage value which has just been measured is the same or not as that measured during step 260. In the event of non-equality, the control unit deduces during step 265 that there is a short circuit between the first phase and the second phase and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 266 that no short circuit exists between these two phases.Steps 265 and 266 complete the detection by the control unit 40 of a short circuit between the first phase and the second phase. When step 266 is performed, the control unit 40 can proceed to test for the existence of a short circuit between the first phase and the third phase according to steps 270 to 276.

[0125] During step 270, a measurement of the voltage across the measuring resistor 17 is carried out to establish a reference measurement. During step 271, the control unit 40 commands the closing of the switch 8 of the switching arm 7 for the first phase arranged between the midpoint 9 of this arm 7 and the terminal at the positive DC potential, and the closing of the switch 8 of the switching arm 7 for the third phase arranged between the midpoint 9 of this arm 7 and ground. All the other switches of the other switching arms 7 are controlled to be in the open position. During step 272, a time delay, for example of 1 ms, is applied. In step 273, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. In step 274, the control unit 40 determines whether the voltage value which has just been measured is the same or not as that measured in step 270.In the event of non-equality, the control unit deduces during step 275 that there is a short circuit between the first phase and the third phase and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 276 that no short circuit exists between these two phases. Steps 275 and 276 complete the detection by the control unit 40 of a short circuit between the first phase and the third phase. When step 276 is carried out, the control unit 40 can proceed to test for the existence of a short circuit between the second phase and the third phase according to steps 280 to 286.

[0126] In step 280, a measurement of the voltage across the measuring resistor 17 is carried out to establish a reference measurement. In step 281, the unit of control 40 controls the closing of the switch 8 of the switching arm 7 for the second phase arranged between the midpoint 9 of this arm 7 and the terminal at the positive DC potential, and the closing of the switch 8 of the switching arm 7 for the third phase arranged between the midpoint 9 of this arm 7 and the ground. All the other switches of the other switching arms 7 are controlled to be in the open position. During step 282, a time delay, for example of 1 ms, is applied. During step 283, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. During step 284, the control unit 40 determines whether the voltage value which has just been measured is the same or not as that measured during step 280.In the event of non-equality, the control unit deduces during step 285 that there is a short circuit between the second phase and the third phase and it sends a message stating that it is impossible to connect the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 286 that no short circuit exists between these two phases. Steps 285 and 286 complete the detection by the control unit 40 of a short circuit between the second phase and the third phase. When step 286 is performed, the control unit can proceed to test a short-circuit state of the switches 32, 34 of the switching arms 31 comprising a midpoint 33, 35 intended to be connected to the primary of the transformer 30 of the DC / DC voltage converter 25 arranged between a midpoint 33, 35 and the terminal with positive DC potential, according to steps 290 to 296.

[0127] In step 290, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 291, the control unit 40 commands the closing of all the switches 32, 34 arranged between a midpoint 33, 35 and ground and the opening of all the switches 32, 34 arranged between a midpoint 33, 35 and the positive DC potential. In step 292, a time delay, for example of 1 ms, is applied. In step 293, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 294, the control unit 40 determines whether the voltage value measured in step 293 is the same or not as that measured in step 290.In the event of non-equality, the control unit deduces during step 295 that one of the switches 32, 34 arranged between the positive DC potential and a midpoint 33, 35 is in a short-circuit state and it sends a message stating that it is impossible to connect the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 296 that none of the switches 32, 34 arranged between the positive DC potential and a midpoint 33, 35 is in a short-circuit state. Steps 295 and 296 complete the detection by the control unit 40 of a short-circuit state of one of the switches 32, 34 arranged between a midpoint and the positive DC potential. When step 296 is performed, the control unit can proceed to test for a short-circuit state of the in . switches 32, 34 of the switching arms 31 of the DC / DC converter 25 arranged between a midpoint 33, 35 and ground, according to steps 300 to 306.

[0128] In step 300, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 301, the control unit 40 commands the closing of all the switches 32, 34 arranged between a midpoint 33, 35 and ground, and the opening of all the switches 32, 34 arranged between a midpoint 33, 35 and the positive DC potential. In step 302, a time delay, for example of 1 ms, is applied. In step 303, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 304, the control unit 40 determines whether the voltage value measured in step 303 is the same or not as that measured in step 300.In the event of non-equality, the control unit deduces during step 305 that one of the switches 32, 34 arranged between ground and a midpoint 33, 35 is in a short-circuit state and it sends a message stating that it is impossible to connect the connector 3 to the electrical network. In the event of equality, the control unit deduces during step 306 that none of the switches 32, 34 arranged between ground and a midpoint 33, 35 is in a short-circuit state. Steps 305 and 306 complete the detection by the control unit 40 of a short-circuit state of one of the switches 32, 34 arranged between a midpoint and ground. When step 306 is performed, the control unit can proceed to test for a short-circuit condition between the switching arms 31 of the DC / DC converter 25, according to steps 310 to 316.

[0129] In step 310, a measurement of the voltage across the measuring resistor 17 is performed to establish a reference measurement. In step 291, the control unit 40 commands the closing of the switch 32 arranged between the midpoint 33 and the terminal at the positive DC potential and the closing of the switch 34 arranged between the midpoint 35 and ground, the other switches 32, 34 being controlled to be in the open position. In step 312, a time delay, for example of 1 ms, is applied. In step 313, a measurement of the voltage across the measuring resistor 17 is performed by the control unit 40. In step 314, the control unit 40 determines whether the voltage value measured in step 313 is the same or not as that measured in step 310.In the event of non-equality, the control unit deduces in step 315 that there is a short circuit between the switching arms and it sends a message of impossibility of connecting the connector 3 to the electrical network. In the event of equality, the control unit deduces in step 316 that no short circuit exists between these two arms. Steps 315 and 316 complete the detection by the control unit 40 of a short circuit between the switching arms 31 of the DC / DC voltage converter 25. When step 316 is carried out, the control unit 40 can proceed to step 320 according to which it determines that there is none of the . aforementioned defects which exist and that the connector 3 can be connected to the electrical network.

[0130] The invention is not limited to what has been described with reference to the figures.

[0131] Other locations are possible for the measuring resistor 17, for example a series connection of this measuring resistor 17 with the capacitor 14 arranged between the positive DC potential and the fifth midpoint 15. A location of this measuring resistor 17 elsewhere than in series with one of the capacitors 14 is possible, for example the measuring resistor 17 can be mounted at one of the terminals with DC potential not being ground, between the capacitor 14 arranged on one side of the fifth midpoint 15, and the switch 11 arranged on one side of the fourth midpoint 12.

[0132] According to one embodiment, steps 230 to 236 and 240 to 245 are not carried out for all the switches 8 of the switching arms 7 of the inverter / rectifier 6, but for a single switching arm 7, these steps being repeated successively for each switching arm 7.

[0133] According to one embodiment, the measurement steps 211, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310 according to [Fig. 3] are not carried out, and the comparison steps 215, 224, 234, 243, 253, 263, 273, 283, 294, 304, 314 are carried out between the measurements 214, 223, 233, 243, 253, 263, 273, 283, 293, 303, 313 respectively and the reference measurement 201.

[0134] In all that has been described, the electrical quantity measured in steps 201, 211, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310 and in steps 214, 223, 233, 243, 253, 263, 273, 283, 293, 303, 313 according to [Fig. 3] may not be the voltage across the measuring resistor but may be the current flowing through this resistor.

Claims

Claims

1. A computer-implemented method for determining at least two short-circuit states within an on-board charger device (1) for a vehicle intended to be connected to an alternating voltage and comprising a measuring resistor (17), the determination of the short-circuit states being made from the comparison of a reference measurement of an electrical quantity and at least one measurement of this same quantity per short-circuit state to be determined, the method being characterized in that all the measurements of the electrical quantity are associated with the measuring resistor (17).

2. Method according to claim 1, the on-board charger device (1) comprising a controllable switch (20) arranged in parallel with the measuring resistor (17), the method comprising: - measuring (201) the electrical quantity associated with the measuring resistor (17) in order to establish (202) a first reference measurement; - controlling (203) said switch (20), controlled to be in the open position; - measuring (205) the electrical quantity associated with the measuring resistor (17); - determining (206) a first short-circuit state of said switch from the detection of an absence of difference between the previous measurement and the reference measurement.

3. Method according to the preceding claim, the device (1) comprising a switching arm (10) comprising two controllable switches (11) on either side of a midpoint (12) intended to be connected to the neutral of an alternating voltage, the first and second switches (11) being intended to be connected to a first and a second direct potential respectively, the method comprising: - measuring (211) the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement; - controlling (212) the two switches (11) of said arm (10), one being controlled to be in the open position, the other to be in the closed position; - measuring (214) the electrical quantity associated with the measuring resistor (17); - determining (215) a short-circuit state of the switch (11) controlled to be in the open position from the detection of a

4.

5. difference (216) between the previous measurement and the reference measurement; - the measurement (220) of the electrical quantity associated with the measurement resistance (17) in order to establish a reference measurement; - the control (221) of the two switches (11), the switch previously in the open position being controlled to be in the closed position and vice versa; - the measurement (223) of the electrical quantity associated with the measuring resistance; - determining (224) a short-circuit state of the switch (11) controlled to be in the open position from the detection of a difference between the previous measurement and the reference measurement. Method according to the preceding claim, the device (1) comprising an additional switch (21) arranged between the midpoint (12) of the switching arm (10) intended to be connected to the neutral of the alternating voltage, and the midpoint (15) of a branch (13) comprising two capacitors (14) arranged on either side of this midpoint (15), the first and second capacitors (14) being intended to be connected to the first and second direct potential, the driving steps (212, 221) of the preceding claim comprising driving said additional switch (21) to be in the open position, the steps of determining (224, 215) a short-circuit state of the preceding claim also making it possible to determine a short-circuit state of said additional switch (21). Method according to any one of claims 3 or 4, the device (1) comprising a switching arm (7), comprising two controllable switches (8) arranged on either side of a midpoint (9) intended to be connected to a phase of an alternating voltage, the first and the second switch (8) being intended to be connected to the first and second direct potential respectively, the method comprising: - the measurement (230) of the electrical quantity associated with the measuring resistance (17) in order to establish a reference measurement; - the control (231) of the two switches (8) of said arm (7), one being controlled to be in the open position, the other to be in the closed position; - the measurement (233) of the electrical quantity associated with the measuring resistance (17); - determining (234) a short-circuit state of the controlled switch to be in the open position from the detection of a difference between the previous measurement and the reference measurement; - the measurement (240) of the electrical quantity associated with the measurement resistor (17) in order to establish a reference measurement; - the control (241) of the two switches (8), the switch previously in the open position being controlled to be in the closed position and vice versa; - the measurement (243) of the electrical quantity associated with the measurement resistor (17); - the determination (244) of a short-circuit state of the controlled switch (8) to be in the open position from the detection of a difference between the previous measurement and the reference measurement.

6. Method according to the preceding claim, the device (1) comprising at least two switching arms (7) each comprising two controllable switches (8) arranged on either side of a midpoint (9) intended to be connected to a respective phase of the alternating voltage, the first and second switches (8) of each arm (7) being intended to be connected to the first and second direct potential respectively, the steps of the method of the preceding claim being carried out simultaneously for all said arms (7).

7. Method according to claim 5, the device (1) comprising at least two switching arms (7) each comprising two controllable switches (8) arranged on either side of a midpoint (9) intended to be connected to a respective phase of the alternating voltage, the first and second switches (8) of each arm (7) being intended to be connected to the first and second direct potential respectively, the steps of the method of claim 5 being carried out successively for each of said arms (7).

8. Method according to any one of claims 5 to 7, the device (1) comprising at least one switching arm (7) comprising two controllable switches (8) arranged on either side of a midpoint (9) intended to be connected to a respective phase of the alternating voltage, the first and second switches (8) of each arm (7) being intended to be connected to the first and second direct potential respectively, the method comprising: - measuring (250) the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement; - controlling (251) the two switches (8) of the at least one switching arm (7) comprising a midpoint (9) intended to be connected

9. at a respective phase of the alternating voltage, the switch (8) intended to be connected to the first direct potential being controlled to be in the closed position, the switch (8) intended to be connected to the second direct potential being controlled to be in the open position; - the control (251) of the two switches (11) of the switching arm (10) comprising a midpoint (12) intended to be connected to the neutral of the alternating voltage, the switch (11) intended to be connected to the first direct potential being controlled to be in the open position, the switch (11) intended to be connected to the second direct potential being controlled to be in the closed position; - the measurement (253) of the electrical quantity associated with the measuring resistance (17); - determining (254) a short-circuit state between the at least one switching arm (7) comprising a midpoint (9) intended to be connected to a respective phase of the alternating voltage and the switching arm (10) comprising a midpoint (12) intended to be connected to the neutral of the alternating voltage from the detection of a difference between the previous measurement and the reference measurement. Method according to any one of claims 6 to 8, the device (1) comprising at least two switching arms (7), each comprising two controllable switches (8) arranged on either side of a midpoint (9) intended to be connected to a respective phase of an alternating voltage, the first and second switches (8) being intended to be connected to the first and second direct potential respectively, the method comprising: - the measurement (260) of the electrical quantity associated with the measuring resistance (17) in order to establish a reference measurement; - the control (261) of the switches of two of said switching arms (7), the switch (8) intended to be connected to the first continuous potential of the first arm (7) being controlled to be in the closed position, the switch (8) intended to be connected to the second continuous potential of the second arm (7) being controlled to be in the closed position, the other switches (8) of said arms (8) being controlled to be in the open position; - the measurement (263) of the electrical quantity associated with the measuring resistance (17); - determining (264) a short-circuit state between the two switching arms (7) from the detection of a difference between the previous measurement and the reference measurement.

10. Method according to the preceding claim, the steps of the method of the preceding claim being carried out successively for each pair of switching arms (7) comprising a midpoint (9) intended to be connected to a respective phase of the alternating voltage.

11. Method according to any one of claims 9 to 10, the device (1) comprising at least two switching arms (31), each comprising two controllable switches (32, 34) arranged on either side of a midpoint (30, 31) intended to be connected to a primary winding of a transformer (30) of a DC / DC voltage converter (25), the first switch and the second switch (32, 34) of each arm (31) being intended to be connected to the first and second DC potential respectively, the method comprising: - measuring (290) the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement;- the control (291) of the switches of said switching arms (31), the switches (32, 34) intended to be connected to the first DC potential being controlled to be in the closed position and the switches (32, 34) intended to be connected to the second DC potential being controlled to be in the open position; - the measurement (293) of the electrical quantity associated with the measuring resistor (17); - the determination (294) of a short-circuit state of the switches (32, 34) controlled to be in the open position from the detection of a difference between the previous measurement and the reference measurement; - the measurement (300) of the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement; - the control (301) of the switches (32, 34) of said switching arms (31), the switches (32, 34) previously in the open position being controlled to be in the closed position and vice versa;- the measurement (303) of the electrical quantity associated with the measuring resistance (17); - the determination (304) of a short-circuit state of the switches (32, 34) controlled to be in the open position from the detection of a difference between the previous measurement and the reference measurement;

12. Method according to the preceding claim, the method comprising - measuring (310) the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement; - controlling (311) the switches (32, 34) of two of the switching arms (31) comprising a midpoint (33, 35) intended to be connected to a primary winding of a transformer (30) of a DC / DC voltage converter (25), the switch (32, 34) intended to be connected to the first DC potential of the first arm (31) being controlled to be in the closed position, the switch (32, 34) intended to be connected to the second DC potential of the second arm (31) being controlled to be in the closed position, the other switches (32, 34) being controlled to be in the open position; - measuring (313) the electrical quantity associated with the measurement resistance; - determining (314) a short-circuit state between said two switching arms (31) from the detection of a difference between the previous measurement and the reference measurement.

13. Method according to the preceding claim, the steps of the method of the preceding claim being carried out successively for each pair of switching arms (31) comprising a midpoint (33, 35) intended to be connected to a primary winding of a transformer (30) of a DC / DC voltage converter (25).

14. Method according to any one of claims 3 to 13, the steps of measuring the electrical quantity associated with the measuring resistor (17) in order to establish a reference measurement being omitted beyond the first step of measuring (201) the electrical quantity in order to establish a first reference measurement (202), each step of determining a short-circuit state carrying out a comparison between the first reference measurement (202) and the measurement carried out previously at this said step of determining a short-circuit state.

15. A method according to any preceding claim, the method returning a signal prohibiting connection of the on-board charger device (1) to the AC voltage source if a short-circuit condition is determined during a step of said method.

16. A method according to any preceding claim, the method comprising a final step (320) when no short circuit condition has been determined in one of its steps of determining a short circuit condition, the method returning a signal authorizing the connection of the on-board charger device (1) to the alternating current source.

17. A method according to any preceding claim, the method comprising timing steps between the driving steps and the measurement steps.

18. Method according to any preceding claim, the electrical quantity being the voltage across the measuring resistor (17).

19. On-board charger device (1) for a vehicle comprising a connector (3) intended to be connected to an electrical network supplying a three-phase alternating voltage, an inverter / rectifier (6), comprising three switching arms (7) mounted in parallel, each switching arm (7) comprising two switches (8) arranged on either side of a midpoint (9), this midpoint being intended to be connected to a respective phase of the alternating voltage, a fourth switching arm (10) mounted in parallel with the switching arms (7) of the inverter / rectifier (6), this fourth switching arm (10) comprising two switches (11) arranged on either side of a fourth midpoint (12) intended to be connected to the neutral of the alternating voltage, and a branch (13) mounted in parallel with said switching arms (7, 10), comprising two capacitors (14) arranged on either side of a fifth midpoint (15),the branch (13) and the switching arms (7, 10) being mounted between two terminals with direct potential, a switch (21) mounted in series between the fourth and the fifth midpoint, a DC / DC voltage converter (25) mounted in cascade with the fourth switching arm (10) and the branch (13) comprising the two capacitors (14), comprising at least two switching arms (31), each having two switches (32, 34) arranged on either side of a midpoint (33, 35) intended to be connected to a primary winding of a transformer (30) of said converter, and a measuring resistor (17), mounted in parallel with a switch (20); and - a control unit (40) of said on-board vehicle charger, comprising the means for implementing the method according to any preceding claim.,

20. Device according to the preceding claim, the measuring resistor (17) being connected in series with the capacitor (14) arranged between the fifth midpoint (15) and one of the terminals with direct potential, said terminal with direct potential being ground.

21. Computer program product, comprising instructions which cause the control unit (40) of the device according to claim 19 to implement the steps of the method according to any one of claims 1 to 18.

22. Computer-readable medium, on which the computer program according to the preceding claim is recorded.

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