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: Diagnostic method for an on-board charger device

[0001] This application relates to a diagnostic method for an on-board vehicle charger. Such a charger provides electrical power to a vehicle's electrical energy storage unit. 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 an alternating voltage of charging terminal and providing a DC output 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 employ a plurality of controllable electronic switches, such as MOSFET transistors or IGBTs. A failure in one of these switches can lead to a short circuit across the terminals of that controllable electronic switch. There is a risk of tripping a charging terminal connected to the on-board charger as a result of such a fault. Furthermore, if the on-board charger is not disabled, there is a risk that the next time the on-board charger is connected to another charging terminal, that other terminal will also trip. To avoid such a risk, it is known to place fuses between the inverter / rectifier and the connector for connecting the on-board charger to the charging terminal. The use of fuses generates an additional cost and may result in additional bulk.Furthermore, the use of fuses generates losses and heat.

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

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

[0006] This method makes it possible to determine short-circuit states in the on-board charger device before connecting said device to the charging terminal, which may make it possible to completely eliminate the need for fuses in said device.

[0007] This method also has the advantage of being able to determine the various short-circuit states for numerous elements of the on-board charger device using only this single measuring resistor. This solution is therefore advantageous because it requires a reduced number of components to determine the short-circuit states.

[0008] The on-board charger device may include 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 an initial reference measure;

[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] - the determination of 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 limits the impact of the resistor's presence during normal operation of the on-board charger. The presence of this switch necessitates an initial series of steps to determine if it is short-circuited before proceeding with 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 can be equal to 600ms.

[0015] The on-board charger device may include a switching arm comprising two controllable switches 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 second DC 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 controlled 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 include an additional controllable switch disposed between the midpoint intended to be connected to the neutral of the alternating voltage, and the midpoint of a branch comprising two capacitors disposed on either side of this midpoint, the first and second capacitors being intended to be connected to the first and second DC potentials respectively. The control steps for the switches of the branch comprising the midpoint intended to be connected to the neutral of the alternating voltage may then include controlling said additional switch to be in the open position. The steps for determining a short-circuit state of the switches of said switching arm then allow for determining 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 above to be charged.

[0025] The device may include 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 DC potentials 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 controlled to be in the closed position and vice versa;

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

[0032] - the determination of 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 include at least two switching arms, comprising Each arm has 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 are intended to be connected to the first and second DC potentials, respectively. The control steps for the switches of the switching arm comprising a midpoint intended to be connected to a phase of the alternating voltage, as described previously, can then be performed simultaneously for all said switching arms. Consequently, the steps for determining a short-circuit state of the switch of the switching arm comprising a midpoint intended to be connected to a phase of the alternating voltage, controlled to be in the open position, as described previously, allow a short-circuit state to be determined for all said switching arms.

[0034] Alternatively, the steps of piloting 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 piloted to be in the open position of said switching arm as described above are repeated successively for each switching arm comprising a midpoint intended to be connected to a respective phase of the alternating voltage.

[0035] The device may include 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 DC potentials 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 and second switches being intended to be connected to the first and second DC potentials 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 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 DC potential being controlled to be in the closed position, the switch intended to be connected to the second continuous potential is 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 direct potential being controlled to be in the open position, the one intended to be connected to the second direct potential being controlled to be in the closed position;

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

[0040] - the determination of a short-circuit state between at least one switching arm including a midpoint intended to be connected to a respective phase of the alternating voltage and the switching arm including 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 include 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 DC potentials 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] - the determination of a short-circuit state between the two switching arms based on the detection of a difference between the previous measurement and the reference measurement.

[0046] The control steps of the switches of two of the switching arms comprising a midpoint intended to be connected to a respective phase of the alternating voltage, of measurement and determination of a short-circuit state between the two switching arms as described above 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 by at least one switching arm including a midpoint intended to be connected to a respective phase of the alternating voltage corresponds to an advantageous embodiment of the present method, allowing to traverse the switches progressively from the measuring resistance towards the alternating voltage source and to ensure that the device is suitable to be connected to the alternating voltage source.

[0048] The device may include at least two switching arms, each comprising two controllable switches 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 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] - the determination of 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 switches previously in open position being piloted to be in closed position, and vice versa;

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

[0055] - the determination of 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 include:

[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 midpoint intended to be connected to a primary winding of a DC / DC voltage converter transformer, 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] - the determination of a short-circuit state between said two switching arms based on the detection of a difference between the previous measurement and the reference measurement.

[0061] The control steps of 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 measurement and determination of a short-circuit state between said two switching arms as described above 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 for measuring the electrical quantity associated with the measuring 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 performs a comparison between the first reference measurement and the measurement performed previously in that step of determining a short-circuit state.

[0063] The method may include a final step if no short-circuit state has been determined in one of its steps for determining a short-circuit state, the method returning a signal enabling the connection of the on-board charger device to the AC power 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 state is determined during a step of said method.

[0065] In all the above, a timing step may be carried out between the switching control steps and the measurement steps, this timing being able to be 1ms.

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

[0067] Alternatively, the electrical quantity can be the current flowing through the measuring resistance.

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

[0069] - a connector intended to be plugged into 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 switching arms being mounted between two terminals at DC potential,

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

[0074] - a DC / DC voltage converter mounted 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, connected in parallel with a switch; and

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

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

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

[0079] Alternatively, the measuring resistor can be mounted in series with the capacitor disposed between the fifth midpoint and one of the DC potential terminals not being ground.

[0080] Alternatively, the measuring resistance can be mounted at one of the DC potential terminals not being ground, between the capacitor located on one side of the fifth midpoint, and the switch located on one side of the fourth midpoint.

[0081] In all the foregoing, the measuring resistance can be a simple resistor, that is, an impedance whose resistance value remains constant. Alternatively, this measuring resistance can be a thermistor. For example, it could be a positive temperature coefficient thermistor, also known as a PTC thermistor. The invention is not limited to a resistor; the use of an inductor is also possible.

[0082] The invention also relates, according to one of its aspects, to a computer program product, comprising instructions which lead the control unit of the on-board charger device as described above to perform 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 will be better understood upon reading the following description of non-limiting examples of its implementation:

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

[0086] - [Fig.2] is a diagram representing the different defects whose existence may be detected in the component of [Fig. 1], and

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

[0088] Figure 1 shows an example of an electrical circuit 2 of an on-board charger 1 for charging an electrical energy storage unit, also called a "charger". The electrical energy storage unit is a battery used to power 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 of 50 Hz or 60 Hz and whose RMS value is 230 V or 240 V. The electrical network is connected to the electrical circuit 2 via a connector 3 shown schematically in [Fig. 1].

[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, connected in series with one of the capacitors 14. The measuring resistance 17 is here a positive temperature coefficient thermistor, also called "PTC" in English.

[0094] All the switches 8 here are 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 at DC potential. It can also be seen in the example considered:

[0096] - that the measuring resistor 17 is connected in series between 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 can correspond to a pre-charge 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.1], another capacitor 18 is mounted in parallel with branch 13.

[0101] The electrical circuit 2, as shown in [Fig. 1], also includes a DC / DC converter 25. This DC / DC converter 25 comprises, as is known, two DC / AC converters 28 and 29. [Fig. 1] shows that the DC / AC converter 28 is 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 DC potential terminals, one being ground, and said switches being MOSFET transistors. The DC / AC converter 29, on the other hand, is unidirectional, being 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. 1], an AC current filtering stage 35 may be provided, this filtering stage 35 being arranged in series between connector 3 and the inverter / rectifier 6. This filtering stage 35 allows, in particular when the AC voltage is polyphase, common-mode current filtering and / or differential current filtering. As shown, relays may be present to allow switching from three-phase mode to single-phase mode, and vice versa.

[0103] Where appropriate, and as shown in [Fig.1], another DC 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.1].

[0104] Component 1 is advantageously fuse-free.

[0105] Component 1 includes a control unit 40, the role of which will be described below. This control unit 40 is, for example, implemented using several modules, as can be seen in [Fig. 1]. This control unit 40 includes, for example, microcontrollers and / or integrated circuits such as ASICs or FPGAs.

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

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

[0108] - according to 102 if the second switch 21 is in a short-circuited state and if one of the 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 the inverter / Rectifier 6 is in a short-circuit state.

[0110] - according to 104 if there is a short circuit between one 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 alternative,

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

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

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

[0115] The various steps involved in establishing this diagnosis will now be described with reference to [Fig.3]. To carry out these steps, the control unit 40 performs, in the example considered, a sequence of measurements of the voltage across the measuring resistor 17 and, using these measurements, determines the existence or absence of several of these faults, one 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, according to the result of this comparison, the control unit 40 determines whether the defect 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 step 201, a first reference value, without the application of an external voltage. In step 202, the control unit 40 controls the opening of the first switch 20 arranged in parallel with the measuring resistor 17. In step 203, the control device controls a switch not shown in [Fig. 1] so as to supply a DC voltage from the control unit 40's power supply across the branch 13. This DC voltage has a value of 18V. A time delay, for example of 1ms, is applied according to step 204.

[0118] In step 205, the voltage across the measuring resistor 17 is measured. In step 206, the control unit determines whether the voltage value measured in step 205 is the same as that measured in step 201. If they are equal, the control unit deduces in step 207 that the first switch 20 is short-circuited and sends a message indicating that connector 3 cannot be connected to the electrical network. If they are not equal, the control unit deduces in step 208 that the first switch 20 is not short-circuited. 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 performed, the control unit can proceed to test for a short-circuit state of the second switch 21 according to steps 210 to 217.

[0119] In step 210, a time delay, for example of 600 ms, is applied. In step 211, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 212, the control unit 40 commands the closing of the switch 11 located between ground and the fourth midpoint 12, the opening of the switch 11 located between the terminal at positive potential and the fourth midpoint 12, and the opening of the switch 21 located between the midpoint 12 of the switching arm 10 and the midpoint 15. In 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.If the two signals are not equal, the control unit in step 216 deduces that the switch 11 located between the fourth midpoint 12 and the positive DC terminal is short-circuited, or that the second switch 21 is short-circuited, and it sends a message indicating that connector 3 cannot be connected to the electrical network. If the signals are still equal, the control unit in step 217 deduces that the second switch 21 is not short-circuited. Steps 216 and 217 complete the detection by the control unit 40 of a short-circuit state in the second switch. switch 21. When step 217 is performed, the control unit can proceed to test for a short-circuit state of the switch 11 located between 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 taken to establish a reference measurement. In step 221, the control unit 40 commands the closing of the switch 11 located between the terminal at positive DC potential and the fourth midpoint 12, and the opening of the switch 11 located between ground and the fourth midpoint 12. In step 222, a time delay, for example of 1 ms, is applied. In step 223, the control unit 40 takes a measurement of the voltage across the measuring resistor 17. In step 224, the control unit 40 determines whether the voltage value measured in step 224 is the same as that measured in step 221.If the results are not equal, the control unit in step 225 deduces that the switch 11 located between ground and the fourth midpoint 12 is short-circuited and sends a message indicating that connector 3 cannot be connected to the electrical network. If the results are also equal, the control unit in step 226 deduces that the switch 11 located between ground and the fourth midpoint 12 is not short-circuited. Steps 225 and 226 complete the detection by the control unit 40 of a short-circuit state of the switch 11 located between ground and the fourth midpoint 12. When step 226 is performed, the control unit can proceed to test for a short-circuit state of the switches 8 of the inverter / rectifier 6 located between a midpoint 9 and one of the DC potential terminals according to steps 230 to 236.

[0121] In step 230, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 231, the control unit 40 commands the closing of all switches 8 located between a midpoint 9 and ground and the opening of all switches 8 located 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, the control unit 40 takes a measurement of the voltage across the measuring resistor 17. In step 234, the control unit 40 determines whether the voltage value measured in step 233 is the same as that measured in step 230.If there is a tie, the control unit in step 235 deduces that one of the switches 8 located between the positive DC potential and a midpoint 9 is short-circuited and sends a message indicating that connector 3 cannot be connected to the electrical network. If there is a tie, the control unit in step 236 deduces that none of the switches 8 located between the positive DC potential and a midpoint 9 is short-circuited. Steps 235 and 236 complete the detection process. 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 for a short-circuit state of the switches 8 of the inverter / rectifier 6 arranged between a midpoint 9 and the other of the DC potential terminals, here ground, according to steps 240 to 245.

[0122] In step 240, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 241, the control unit 40 commands the closing of all switches 8 located between a midpoint 9 and the positive DC potential and the opening of all switches 8 located between a midpoint 9 and ground. In step 242, a time delay, for example of 1 ms, is applied. In step 243, the control unit 40 takes a measurement of the voltage across the measuring resistor 17. In step 244, the control unit 40 determines whether the voltage value just measured is the same as that measured in step 240.In the event of a tie, the control unit deduces in step 245 that one of the switches 8 located between ground and a midpoint 9 is short-circuited and sends a message indicating that connector 3 cannot be connected to the electrical network. In the event of a tie, the control unit deduces in step 246 that none of the switches 8 located between ground and a midpoint 9 is short-circuited. Steps 245 and 246 complete the detection by the control unit 40 of a short-circuit state in one of the switches 8 located between a midpoint and ground. Once step 246 is completed, the control unit 40 can proceed to test for the existence of a short circuit between a phase of the AC voltage and neutral according to steps 250 to 256.

[0123] In step 250, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 251, the control unit 40 commands the closing of all the switches 8 located between a midpoint 9 and the positive DC potential, the opening of all the switches 8 located between a midpoint 9 and ground, and the opening of the switch 11 located between the fourth midpoint 12 and ground. In step 252, a time delay, for example of 1 ms, is applied. In step 253, the control unit 40 takes a measurement of the voltage across the measuring resistor 17. In step 254, the control unit 40 determines whether the voltage value just measured is the same as that measured in step 250.In the event of a tie, the control unit deduces in step 255 that there is a short circuit between one of the phases and the neutral and sends a message indicating that connector 3 cannot be connected to the electrical network. In the event of a tie, the control unit deduces in step 256 that no phase is short-circuited to the neutral. Steps 255 and 256 complete the detection by 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 the 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 voltage measurement across the measuring resistor 17 is taken to establish a reference measurement. In step 261, the control unit 40 commands the closing of switch 8 on the switching arm 7 for the first phase located between the midpoint 9 of this arm 7 and the terminal at positive DC potential, and the closing of switch 8 on the switching arm 7 for the second phase located between the midpoint 9 of this arm 7 and ground. All other switches on the other switching arms 7 are controlled to be in the open position. In step 262, a time delay, for example of 1 ms, is applied. In step 263, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. In step 264, the control unit 40 determines whether the voltage value that has just been measured is the same or not as that measured in step 260.If the results are not equal, the control unit in step 265 deduces that there is a short circuit between the first and second phases and sends a message indicating that connector 3 cannot be connected to the electrical network. If the results are equal, the control unit in step 266 deduces that no short circuit exists between these two phases. Steps 265 and 266 complete the detection by control unit 40 of a short circuit between the first and second phases. Once step 266 is completed, control unit 40 can proceed to test for the existence of a short circuit between the first and third phases according to steps 270 to 276.

[0125] In step 270, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 271, the control unit 40 commands the closing of switch 8 on the switching arm 7 for the first phase located between the midpoint 9 of this arm 7 and the terminal at positive DC potential, and the closing of switch 8 on the switching arm 7 for the third phase located between the midpoint 9 of this arm 7 and ground. All other switches on the other switching arms 7 are driven to be in the open position. In 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 taken by the control unit 40. In step 274, the unit Control unit 40 determines whether the measured voltage value is the same as the value measured in step 270. If they are not equal, the control unit infers in step 275 that there is a short circuit between the first and third phases and sends a message indicating that connector 3 cannot be connected to the electrical network. If they are equal, the control unit infers in step 276 that there is no short circuit between these two phases. Steps 275 and 276 complete the detection by control unit 40 of a short circuit between the first and third phases. Once step 276 is completed, control unit 40 can proceed to test for the existence of a short circuit between the second and third phases in steps 280 to 286.

[0126] In step 280, a voltage measurement across the measuring resistor 17 is taken to establish a reference measurement. In step 281, the control unit 40 commands the closing of switch 8 on the switching arm 7 for the second phase located between the midpoint 9 of this arm 7 and the terminal at positive DC potential, and the closing of switch 8 on the switching arm 7 for the third phase located between the midpoint 9 of this arm 7 and ground. All other switches on the other switching arms 7 are controlled to be in the open position. In step 282, a time delay, for example of 1 ms, is applied. In step 283, a measurement of the voltage across the measuring resistor 17 is carried out by the control unit 40. In step 284, the control unit 40 determines whether the voltage value that has just been measured is the same or not as that measured in step 280.If the results are not equal, the control unit in step 285 deduces that there is a short circuit between the second and third phases and sends a message indicating that connector 3 cannot be connected to the electrical network. If the results are equal, the control unit in step 286 deduces that no short circuit exists between these two phases. Steps 285 and 286 complete the detection by control unit 40 of a short circuit between the second and third phases. 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 disposed between a midpoint 33, 35 the terminal at positive DC potential, according to steps 290 to 296.

[0127] In step 290, a measurement of the voltage across the measuring resistor 17 is taken to establish a reference measurement. In step 291, the control unit 40 commands the closing of all switches 32, 34 located between a midpoint 33, 35 and ground and the opening of all switches 32, 34 located 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 The voltage across the measuring resistor 17 is measured by the control unit 40. In step 294, the control unit 40 determines whether the voltage value measured in step 293 is the same as that measured in step 290. If they are not equal, the control unit deduces in step 295 that one of the switches 32, 34 located between the positive DC potential and a midpoint 33, 35 is short-circuited and sends a message indicating that connector 3 cannot be connected to the electrical network. If they are equal, the control unit deduces in step 296 that neither of the switches 32, 34 located between the positive DC potential and a midpoint 33, 35 is short-circuited. 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 a short-circuit state of the 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] During step 300, a measurement of the voltage across the measuring resistor. Step 17 is performed to establish a reference measurement. During step 301, the control unit 40 commands the closing of all switches 32, 34 located between a midpoint 33, 35 and ground, and the opening of all switches 32, 34 located between a midpoint 33, 35 and the positive DC potential. During 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 taken 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. If they are not equal, the control unit deduces in step 305 that one of the switches 32, 34 located between ground and a midpoint 33, 35 is in a short-circuited state and it sends a message indicating that it is impossible to connect the connector 3 to the electrical network.In case of a tie, the control unit deduces in step 306 that none of the switches 32, 34 located between ground and a midpoint 33, 35 is short-circuited. Steps 305 and 306 complete the detection by the control unit 40 of a short-circuit state in one of the switches 32, 34 located between a midpoint and ground. When step 306 is performed, the control unit can proceed to test for a short-circuit state 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 taken to establish a reference measurement. In step 291, the control unit 40 commands the closing of the switch 32 located between the midpoint 33 and the terminal at positive DC potential and the closing of the switch 34 located between the midpoint 35 and ground, the other switches 32, 34 being controlled tobe in the open position. During step 312, a time delay, for example of 1 ms, is applied. During step 313, a voltage measurement across the measuring resistor 17 is taken by the control unit 40. During step 314, the control unit 40 determines whether the voltage value measured during step 313 is the same as that measured during step 310. If they are not equal, the control unit deduces during step 315 that there is a short circuit between the switching arms and sends a message indicating that connector 3 cannot be connected to the power supply. If they are equal, the control unit deduces during step 316 that there is no short circuit 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 completed, the control unit 40 can proceed to step 320, whereby it determines that none of the aforementioned faults exist and that 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 located between the positive DC potential and the fifth midpoint 15. A location of this measuring resistor 17 other than in series with one of the capacitors 14 is possible, for example the measuring resistor 17 can be mounted at one of the DC potential terminals not being ground, between the capacitor 14 located on one side of the fifth midpoint 15, and the switch 11 located 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 only one 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 at steps 201, 211, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310 and at steps 214, 223, 233, 243, 253, 263, 273, 283, 293, 303, 313 according to [Fig.3] may not be the voltage across the measuring resistance but be the current through this resistance.

Claims

Demands

1. A computer-implemented method for determining at least two short-circuit states within an on-board vehicle charger device (1) intended to be connected to an alternating voltage, comprising a measuring resistor (17) and a controllable switch (20) disposed in parallel with the measuring resistor (17), the determination of the short-circuit states being carried out by comparing a reference measurement of an electrical quantity and at least one measurement of that same quantity per short-circuit state to be determined, the method being characterized in that all measurements of the electrical quantity are associated with the measuring resistor (17) and in that it comprises: - the measurement (201) of the electrical quantity associated with the measuring resistor (17) in order to establish (202) a first reference measurement; - the control (203) of said switch (20), controlled to be in the open position;- the measurement (205) of the electrical quantity associated with the measuring resistance (17); - the determination (206) of a first short-circuit state of said switch from the detection of an absence of difference between the previous measurement and the reference measurement.

2. 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 switch (11) being intended to be connected to a first and a second direct current potential respectively, the method comprising: - the measurement (211) of the electrical quantity associated with the measuring resistance (17) in order to establish a reference measurement; - the control (212) of 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; - the measurement (214) of the electrical quantity associated with the measuring resistance (17); - the determination (215) of a short-circuit state of the switch (11) controlled to be in the open position from the detection of a difference (216) between the previous measurement and the reference measurement; - the measurement (220) of the electrical quantity associated with the measuring 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; - the determination (224) of 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.

3. Method according to the preceding claim, the device (1) comprising an additional switch (21) disposed 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) disposed on either side of this midpoint (15), the first and second capacitors (14) being intended to be connected to the first and second DC potential, the piloting steps (212, 221) of the preceding claim comprising piloting said additional switch (21) to be in the open position, the short-circuit determination steps (224, 215) of the preceding claim also enabling the determination of a short-circuit state of said additional switch (21).

4. Method according to any one of claims 2 or 3, the device (1) comprising a switching arm (7), comprising two controllable switches (8) disposed on either side of a midpoint (9) intended to be connected to a phase of an alternating voltage, the first and second switch (8) being intended to be connected to the first and second DC 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); - the determination (234) of a short-circuit state of the switch controlled 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 measuring resistance (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 measuring resistance (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.;

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

6. Method according to claim 4, the device (1) comprising at least two switching arms (7) each comprising two controllable switches (8) disposed on either side of a midpoint (9) intended to be connected to a respective phase of the alternating voltage, the first and second switch (8) of each arm (7) being intended to be connected to the first and second DC potential respectively, the steps of the method of claim 4 being carried out successively for each of said arms (7).

7. A method according to any one of claims 4 to 6, the device (1) comprising at least one switching arm (7) comprising two controllable switches (8) arranged on either side of a point middle (9) intended to be connected to a respective phase of the alternating voltage, the first and second switch (8) of each arm (7) being intended to be connected to the first and second direct potential respectively, the method comprising: - the measurement (250) of the electrical quantity associated with the measuring resistance (17) in order to establish a reference measurement; - the control (251) of the two switches (8) of at least one switching arm (7) comprising a middle point (9) intended to be connected to 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 DC potential being controlled to be in the open position, the switch (11) intended to be connected to the second DC potential being controlled to be in the closed position; - the measurement (253) of the electrical quantity associated with the measuring resistance (17); - the determination (254) of a short-circuit state between 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.

8. Method according to any one of claims 5 to 7, the device (1) comprising at least two switching arms (7), each comprising two controllable switches (8) disposed on either side of a midpoint (9) intended to be connected to a respective phase of an alternating voltage, the first and second switch (8) being intended to be connected to the first and second DC 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 DC potential of the first arm (7) being controlled to be in the closed position, the switch (8) intended to be connected to the second DC 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); - the determination (264) of a short-circuit state between the two switching arms (7) from the detection of a difference between the previous measurement and the reference measurement.

9. 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.

10. A method according to any one of claims 8 to 9, 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 potentials respectively, the method comprising: - the measurement (290) of the electrical quantity associated with the measuring resistance (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 resistance (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 resistance (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;

11. A method according to the preceding claim, the method comprising: - measuring (310) the electrical quantity associated with the measuring resistance (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 measuring resistance;- the determination (314) of a short-circuit state between said two switching arms (31) from the detection of a difference between the previous measurement and the reference measurement.;

12. 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).

13. Method according to any one of claims 2 to 12, the steps of measuring the electrical quantity associated with the measuring resistance (17) in order to establish a reference measurement being omitted beyond the first measurement step (201) of 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 that said step of determining a short-circuit state.

14. Method according to any one of the preceding claims, the method returning a signal prohibiting the connection of the on-board charger device (1) to the AC voltage source if a short-circuit state is determined during a step of said method.

15. Method according to any one of the preceding claims, the method comprising a final step (320) when no short-circuit state has been determined in one of its steps for determining a short-circuit state, the method returning a signal permitting the connection of the on-board charger device (1) to the AC power source.

16. Method according to any one of the preceding claims, the method comprising timing steps between the piloting steps and the measurement steps.

17. Method according to any one of the preceding claims, the electrical quantity being the voltage across the measuring resistance (17).

18. An on-board vehicle charger device (1) comprising a connector (3) for connection to an electrical network supplying 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 and on the other hand of a fifth midpoint (15), the branch (13) and the switching arms (7, 10) being mounted between two terminals at direct current potential, a switch (21) mounted in series between the fourth and fifth midpoints, 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) disposed 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 means for implementing the method according to any one of the preceding claims.

19. Device according to the preceding claim, the measuring resistor (17) being mounted in series with the capacitor (14) disposed between the fifth midpoint (15) and one of the DC potential terminals, said DC potential terminal being ground.

20. Product computer program, comprising instructions that lead the control unit (40) of the device according to claim 18 to implement the steps of the method according to any one of claims 1 to 17.

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

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