Method of controlling converter, apparatus, related device, medium, and computer program

Abstract

To provide a method of controlling a converter, an apparatus, a related device, a medium, and a computer program.SOLUTION: A converter converts an input AC current signal into a DC current signal and charges a battery, and comprises a rectifier circuit unit. A method of control includes: a step of, upon receiving a charging command, generating a reference carrier signal on the basis of a current voltage value of a battery, a target voltage value of the battery, and an AC current signal; a step of generating a first type of a driving signal to control and drive the rectifier circuit unit on the basis of at least the reference carrier signal, where the first type of the driving signal is used for controlling at least a target power device of the rectifier circuit unit being in a normally-off state; and a step of controlling and operating the rectifier circuit unit by using the first type of the driving signal.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to the field of vehicle technologies, and in particular, to a control method, apparatus, related device, medium, and computer program of a converter.

Background Art

[0002] The on-vehicle charger (OBC) of an electric vehicle is used to convert alternating current into direct current to charge the vehicle's power battery. The on-vehicle charger OBC incorporates a converter for converting alternating current into direct current. Currently, an isolated AC-DC converter usually adopts a two-stage structure, which is composed of two independent single-stage converters. The first stage is a power factor correction AC-DC converter, and the second stage is an isolated DC-DC converter. An electrolytic capacitor for energy buffering is connected between the first stage and the second stage. However, the two-stage structure AC-DC converter has problems of many devices and high hardware costs.

[0003] Currently, the market and academia are promoting the development of the two-stage structure AC-DC converter towards a single-stage topology structure. In realizing the above functions, the single-stage structure AC-DC converter not only reduces electrolytic capacitors, but also reduces the number of power electronic switch devices. Compared with the two-stage structure AC-DC converter, the single-stage structure AC-DC converter has a smaller volume, higher efficiency, lower cost, and significantly improved service life.

Summary of the Invention

[0004] In order to overcome the problems existing in the related art, the present disclosure provides a control method, apparatus, related device, medium, and computer program of a converter.

[0005] According to a first aspect of an embodiment of the present disclosure, a method for controlling a converter is provided. The converter converts an input alternating current signal into a direct current signal to charge a battery. The converter includes a rectifier circuit unit. The control method includes: when receiving a charging command, generating a reference carrier signal based on a current voltage value of the battery, a target voltage value of the battery, and the alternating current signal; generating a first type of driving signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal, where the first type of driving signal is used to control at least a target power device of the rectifier circuit unit to be in a normally-off state; and controlling and operating the rectifier circuit unit using the first type of driving signal.

[0006] Optionally, the rectifier circuit unit includes a first bridge arm and a second bridge arm. The first bridge arm includes a first power device and a second power device. The second bridge arm includes a third power device and a fourth power device. The first power device is located on the upper bridge arm of the first bridge arm. The second power device is located on the lower bridge arm of the first bridge arm. The third power device is located on the upper bridge arm of the second bridge arm. The fourth power device is located on the lower bridge arm of the second bridge arm. The target power device includes the first power device and the third power device, or the target power device includes the second power device and the fourth power device.

[0007] Optionally, the first type of drive signal includes a second drive signal for controlling the target power device to be in a normally-off state and a first drive signal for controlling other power devices other than the target power device of the rectifier circuit unit. The step of generating the first type of drive signal for controlling the rectifier circuit unit to operate based on at least the reference carrier signal includes generating a first drive signal for controlling other power devices other than the target power device of the rectifier circuit unit to operate based on the reference carrier signal and a preset duty ratio of the drive signal.

[0008] Optionally, other power devices other than the target power device of the rectifier circuit unit include a first target power device and a second target power device. The step of generating a first drive signal for controlling other power devices other than the target power device of the rectifier circuit unit to operate based on the reference carrier signal and a preset duty ratio of the drive signal includes generating a reference signal based on the reference carrier signal and the preset duty ratio of the drive signal, wherein the amplitude of the reference signal does not change with the phase of the alternating current signal; inputting the reference signal to the positive input terminal of a first comparator, inputting the reference carrier signal to the negative input terminal of the first comparator after shifting the phase of the reference carrier signal by a preset phase, and obtaining a first sub-drive signal for controlling the first target power device to operate output from the first comparator; and inputting the first sub-drive signal to a first inverter and obtaining a second sub-drive signal for driving the second target power device to operate output from the first inverter.

[0009] Optionally, the step of generating a first type of drive signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal includes inputting a preset signal to the positive input terminal of a second comparator, inputting the reference carrier signal to the negative input terminal of the second comparator, and obtaining a second drive signal output from the second comparator, where the second drive signal is further used to control the target power device to be in a normally-off state.

[0010] Optionally, the converter further includes a high-frequency bridge arm, and the control method includes generating a second type of drive signal for controlling and operating the high-frequency bridge arm based on the reference carrier signal and the reference signal, where the first drive signal is delayed by a preset phase from the second type of drive signal, and controlling and operating the high-frequency bridge arm using the second type of drive signal.

[0011] Optionally, the high-frequency bridge arm includes a first pair of tubes and a second pair of tubes, and the second type of drive signal includes a third sub-drive signal for controlling and operating the first pair of tubes and a fourth sub-drive signal for controlling and operating the second pair of tubes. The step of generating a second type of drive signal for controlling and operating the high-frequency bridge arm based on the reference carrier signal and the reference signal includes inputting the reference carrier signal to the negative input terminal of a third comparator, inputting the reference signal to the positive input terminal of the third comparator, and obtaining a third sub-drive signal for controlling and operating the first set of paired tubes output from the third comparator; and inputting the third sub-drive signal to a second inverter, and obtaining a fourth sub-drive signal for controlling and operating the second set of paired tubes output from the second inverter. When the first target power device is the first power device or the fourth power device, the first set of paired tubes includes a fifth power device located on the upper bridge arm of the third bridge arm of the high-frequency bridge arm and an eighth power device located on the lower bridge arm of the fourth bridge arm of the high-frequency bridge arm. When the first target power device is the second power device or the third power device, the first set of paired tubes includes a sixth power device located on the lower bridge arm of the third bridge arm of the high-frequency bridge arm and a seventh power device located on the upper bridge arm of the fourth bridge arm of the high-frequency bridge arm.

[0012] Optionally, the period of the alternating current signal includes a positive half-cycle and a negative half-cycle, the converter further includes a commercial frequency bridge arm, the commercial frequency bridge arm includes a ninth power device and a tenth power device, the ninth power device is located on the upper bridge arm of the commercial frequency bridge arm, the tenth power device is located on the lower bridge arm of the commercial frequency bridge arm, and the control method further includes controlling the tenth power device to be turned on and controlling the ninth power device to be turned off within the positive half-cycle; and controlling the tenth power device to be turned off and controlling the ninth power device to be turned on within the negative half-cycle.

[0013] Optionally, when receiving the charging command, the step of generating a reference carrier signal based on the current voltage value of the battery, the target voltage value of the battery, and the AC current signal includes: obtaining a target current value based on the difference between the current voltage value of the battery and the target voltage value of the battery; obtaining a frequency control parameter based on the target current value and the current value of the AC current signal, where the frequency control parameter can indicate the frequency of the generated reference carrier signal; and generating a reference carrier signal based on the frequency control parameter.

[0014] According to a second aspect of the embodiments of the present disclosure, a control device of a converter is provided. The converter converts an input AC current signal into a DC current signal to charge a battery. The converter includes a rectifier circuit unit. The control device of the converter is configured to, when receiving a charging command, generate a reference carrier signal based on the current voltage value of the battery, the target voltage value of the battery, and the AC current signal; a first generation module; a second generation module configured to generate a first type of drive signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal, where the first type of drive signal is used to control at least the target power device of the rectifier circuit unit to be in a normally-off state; and a first control module configured to control and operate the rectifier circuit unit using the first type of drive signal.

[0015] According to a third aspect of the embodiments of the present disclosure, a control device is provided, including a processor and a memory for storing instructions executable by the processor. The processor is configured to realize the steps of the converter control method described in the first aspect of the embodiments of the present disclosure by executing the instructions.

[0016] According to a fourth aspect of the embodiments of the present disclosure, an in-vehicle charger is provided, including a converter and a control device described in the third aspect of the embodiments of the present disclosure.

[0017] According to a fifth aspect of the embodiments of the present disclosure, a vehicle is provided, including a battery and an in-vehicle charger described in the fourth aspect of the embodiments of the present disclosure.

[0018] According to a sixth aspect of the embodiments of the present disclosure, a computer-readable storage medium storing computer program instructions is provided. When the computer program instructions are executed by a processor, the steps of the converter control method described in the first aspect of the embodiments of the present disclosure are realized.

[0019] According to a seventh aspect of the embodiments of the present disclosure, a computer program is provided. When the computer program is executed by a processor, the steps of the converter control method described in the first aspect of the embodiments of the present disclosure are realized.

[0020] According to the above technical solution, at least based on a reference carrier signal, a first type of drive signal for controlling a rectifier circuit unit is generated. The first type of drive signal is used to control at least that the target power device of the rectifier circuit unit is in a normally-off state, and the rectifier circuit unit is controlled to operate using the first type of drive signal. Thereby, in the charging stage, the problem that the charging efficiency deteriorates due to the backflow of the battery's electricity amount to the converter is avoided, and the reliability of the converter can be further improved.

[0021] It should be noted that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit the present disclosure.

Brief Description of the Drawings

[0022] The drawings here are incorporated into the specification and constitute a part of the specification, showing embodiments of the present invention that conform to the present disclosure, and are used to explain the principles of the embodiments of the present invention together with the specification.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0023] Here, exemplary embodiments will be described in detail, and the examples will be shown in the drawings. When the following description relates to the drawings, unless otherwise expressed, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments that are consistent with the present application. Rather, they are merely examples of devices and methods that are consistent with some aspects of the present application, which are described in detail in the appended claims.

[0024] The embodiments described in some exemplary embodiments of the present disclosure below do not represent all embodiments that are consistent with the present application. Rather, they are merely examples of devices and methods that are consistent with some aspects of the present application, which are described in detail in the appended claims.

[0025] Note that all operations for acquiring signals, information, or data in the present disclosure are performed when permission is given by the owner of the corresponding device on the premise of complying with the corresponding data protection regulations and policies of the country where the location is located.

[0026] Currently, during the operation of a single-stage AC-DC converter, for example, during the charging stage, the amount of electricity in the battery may flow back to the converter, resulting in poor charging efficiency and poor reliability of the converter.

[0027] In view of this point, the present disclosure provides a control method, device, related device, medium, and computer program for a converter, which generates a first type of drive signal for controlling a rectifier circuit unit based on at least a reference carrier signal. The first type of drive signal is used to control at least that the target power device of the rectifier circuit unit is in the normally-off state, and the rectifier circuit unit is controlled to operate using the first type of drive signal. Thereby, the problem that the charging efficiency deteriorates due to the amount of electricity in the battery flowing back to the converter during the charging stage can be avoided, and the reliability of the converter can be further improved.

[0028] FIG. 1 is a schematic diagram of an application scenario shown by an exemplary embodiment. As shown in FIG. 1, a vehicle is provided with an on-vehicle charger (OBC), and the on-vehicle charger (OBC) includes an AC-DC converter with a single-stage structure. When charging is required, the charging gun is inserted into the AC charging pile, and the on-vehicle charger (OBC) receives an AC charging command. Further, under the monitoring of the battery management system (BMS), the on-vehicle charger (OBC) charges the vehicle's battery. Exemplarily, the on-vehicle charger (OBC) converts the alternating current provided by the AC charging pile into direct current to receive power from the battery.

[0029] Hereinafter, the converter will be described.

[0030] In the present disclosure, the converter 1 converts the input alternating current signal into a direct current signal to charge the battery, and this converter includes at least a rectifier circuit unit. Further, this converter may further include a high-frequency bridge arm, a commercial-frequency bridge arm, a filter capacitor, and a transformer unit. FIG. 2 is a block diagram of a converter shown by an exemplary embodiment. As shown in FIG. 2, the converter 1 converts the input alternating current signal into a direct current signal to charge the battery 2. The converter 1 may include a high-frequency bridge arm 10, a commercial-frequency bridge arm 20, a filter capacitor 30, a transformer unit 40, and a rectifier circuit unit 50. Exemplarily, the high-frequency bridge arm 10 may be a full-bridge circuit, and the commercial-frequency bridge arm 20 may be a half-bridge circuit. Here, the high-frequency bridge arm 10 and the commercial-frequency bridge arm 20 can form a power factor correction (PFC) circuit unit. For example, the high-frequency bridge arm and the commercial-frequency bridge arm form a single-phase staggered totem pole PFC topology structure.

[0031] The filter capacitor 30 may be an electrolytic capacitor or a film capacitor.

[0032] Also, as shown in FIG. 2, the converter 1 further includes an alternating current transmission port 60 connected to the high-frequency bridge arm 10 and the commercial-frequency bridge arm 20 respectively to provide an alternating current signal to the high-frequency bridge arm 10 and the commercial-frequency bridge arm 20. The high-frequency bridge arm 10, the commercial-frequency bridge arm 20, and the filter capacitor 30 are connected in parallel. The transformer unit 40 is connected to the high-frequency bridge arm 10 and the rectifier circuit unit 50 respectively.

[0033] During the operation of the converter, any power device in the high-frequency bridge arm 10, the commercial-frequency bridge arm 20, and the rectifier circuit unit 50 can be controlled. The specific control method will be described in detail below.

[0034] FIG. 3 is a flowchart of a control method for a converter shown by an exemplary embodiment. As shown in FIG. 3, this control method can include the following steps S31 to S33.

[0035] In step S31, when a charging command is received, a reference carrier signal is generated based on the current voltage value of the battery, the target voltage value of the battery, and the alternating current signal.

[0036] In step S32, based on at least the reference carrier signal, a first type of drive signal for controlling and operating the rectifier circuit unit is generated, and the first type of drive signal is used to control at least that the target power device of the rectifier circuit unit is in the normally-off state.

[0037] In the present disclosure, when the target power device is in the normally-off state, the corresponding body diode is in the continuous current state.

[0038] In step S33, the rectifier circuit unit is controlled to operate using the first type of drive signal.

[0039] According to the above technical solution, based on at least the reference carrier signal, a first type of drive signal for controlling the rectifier circuit unit is generated, and the first type of drive signal is used to control at least that the target power device of the rectifier circuit unit is in the normally-off state, and the rectifier circuit unit is controlled to operate using the first type of drive signal. Thereby, in the charging stage, the problem that the charging efficiency deteriorates due to the reverse flow of the battery's electricity amount into the converter is avoided, and the reliability of the converter can be further improved.

[0040] It is also possible to control the target power device to be in the synchronous rectification state. In this way, while the body diode is in the continuous current state, the target power device is controlled to turn on, allowing current to flow through the channel of the target power device, further reducing power loss and improving efficiency. However, this method cannot effectively prevent the problem of the battery's electrical quantity flowing back into the converter. Therefore, according to actual needs, it is possible to determine whether to control the corresponding target power device to turn on when the body diode is in the continuous current state.

[0041] The following will explain each step in FIG. 3 in detail.

[0042] In one embodiment, in step S31, when a charging command is received, based on the current voltage value of the battery, the target voltage value of the battery, and the alternating current signal, the step of generating a reference carrier signal includes obtaining a target current value based on the difference between the current voltage value of the battery and the target voltage value of the battery, obtaining a frequency control parameter based on the target current value and the current value of the alternating current signal, where the frequency control parameter can indicate the frequency of the generated reference carrier signal, and generating a reference carrier signal based on the frequency control parameter.

[0043] Exemplarily, FIG. 4 is a schematic diagram of generating a reference carrier signal shown by an exemplary embodiment. As shown in FIG. 4, first, the current voltage value V bat of the battery and the target voltage value V bat * are input into the voltage control loop to obtain the target current value i gd * output from the voltage control loop. Here, the target voltage value refers to the target value of battery charging that can be obtained from the charging command. Also, the alternating current signal i g currently input by the alternating current transmission port and the current signal output after passing through the high-frequency bridge arm and the commercial frequency bridge arm, and this alternating current signal i gBased on this, through the rotation coordinate transformation from the αβ AC current component to the dq DC component, the current tracking value i g corresponding to gd is obtained. Then, the difference between the target current value i gd * and the current tracking value i gd is input into the current control loop, and the frequency control parameter output from the current control loop is obtained. Finally, the frequency control parameter is input into the carrier generator, and the carrier generator generates and outputs a reference carrier signal Fs based on this frequency control parameter, and the frequency of this reference carrier signal corresponds to the frequency of this frequency control parameter.

[0044] For ease of explanation, first, the configuration of the rectifier circuit unit will be described below.

[0045] FIG. 5 is a circuit diagram of a converter shown by an exemplary embodiment. As shown in FIG. 5, the rectifier circuit unit 50 includes a first bridge arm 501 and a second bridge arm 502. The first bridge arm 501 includes a first power device S1 and a second power device S2. The second bridge arm 502 includes a third power device S3 and a fourth power device S4. The first power device S1 is located on the upper bridge arm of the first bridge arm 501. The second power device S2 is located on the lower bridge arm of the first bridge arm 501. The third power device S3 is located on the upper bridge arm of the second bridge arm 502. The fourth power device S4 is located on the lower bridge arm of the second bridge arm 502. Accordingly, the target power devices in the normally-off state can include the first power device S1 and the third power device S3 located on the upper bridge arm, or the target power devices in the normally-off state can include the second power device S2 and the fourth power device S4 located on the lower bridge arm.

[0046] In addition, since the first power device S1 and the third power device S3 located on the upper bridge arm are each connected to the positive electrode of the battery, in order to further avoid the electric quantity of the battery flowing backward into the converter, preferably, the target power device can include the first power device S1 and the third power device S3 located on the upper bridge arm.

[0047] Accordingly, the first type of drive signal includes a second drive signal for controlling the power device to be in the normally-off state and a first drive signal for controlling and operating other power devices other than the target power device of the rectifier circuit unit. In step S32, the step of generating the first type of drive signal for controlling and operating the rectifier circuit unit based at least on the reference carrier signal may include the step of generating the first drive signal for controlling and operating other power devices other than the target power device of the rectifier circuit unit based on the reference carrier signal and the preset duty ratio of the drive signal.

[0048] In the present disclosure, other power devices other than the target power device of the rectifier circuit unit include a first target power device and a second target power device. Exemplarily, assume that the target power device includes the first power device S1 and the third power device S3. The first target power device may be the fourth power device S4, and the second target power device may be the second power device S2. Alternatively, the first target power device may be the second power device S2, and the second target power device may be the fourth power device S4.

[0049] Specific embodiments for generating a first driving signal for controlling and operating power devices other than the target power device of the rectifier circuit unit based on the duty ratio of the reference carrier signal and a preset driving signal may be as follows. First, a reference signal is generated based on the duty ratio of the reference carrier signal and the preset driving signal, and the amplitude of the reference signal does not change according to the phase of the alternating current signal. Exemplarily, the product of the duty ratio and the maximum amplitude of the reference carrier signal can be determined as the reference signal, and this reference signal is a fixed value and does not change according to the phase of the alternating current signal. For example, assuming the duty ratio is 50%, when the maximum amplitude of the reference carrier signal is 1, the reference signal is y = 0.5. When the maximum amplitude of the reference carrier signal is 100, the reference signal is y = 50.

[0050] The duty ratio may be other values, but it should be understood that when the duty ratio is 50%, the energy transmitted by the converter is the largest, that is, the voltage utilization rate of the converter is the highest.

[0051] Next, the reference signal is input to the positive input terminal of the first comparator, and the reference carrier signal is phase-shifted by a preset phase and then input to the negative input terminal of the first comparator to obtain a first sub-driving signal for controlling and operating the first target power device output from the first comparator.

[0052] The preset phase is determined based on the phase of the alternating current signal. Exemplarily, the preset phase and the phase of the alternating current signal exhibit a linear function relationship, and the specific function relationship can be determined in advance by experiments. The range of the preset phase may be 0 to 0.5 rad.

[0053] Thereafter, the first sub-driving signal is input to the first inverter to obtain a second sub-driving signal for driving and operating the second target power device output from the first inverter.

[0054] FIG. 6 is a schematic diagram of generating a first drive signal shown by an exemplary embodiment. As shown in FIG. 6, a reference signal b is input to the positive input terminal of a first comparator A1, and a reference carrier signal Fs is phase-shifted by a preset phase and then input to the negative input terminal of the first comparator A1, so as to obtain a first sub-drive signal for controlling and operating a first target power device output from the first comparator A1. Further, the output terminal of the first comparator A1 is connected to a first inverter F1, that is, the first sub-drive signal is input to the first inverter F1, so as to obtain a second sub-drive signal for controlling and operating a second target power device output from the first inverter F1.

[0055] Also, in step S32, the step of generating a first type of drive signal for controlling and operating a rectifier circuit unit based on at least a reference carrier signal may further include the step of inputting a preset signal to the positive input terminal of a second comparator, inputting the reference carrier signal to the negative input terminal of the second comparator, and obtaining a second drive signal output from the second comparator, where the second drive signal is used to control the target power device to be in a normally-off state.

[0056] The preset signal may be a signal with all amplitudes being 0, or an arbitrary signal with amplitudes not being 0 but smaller than the amplitude of the reference carrier signal at each moment, but the present disclosure is not specifically limited.

[0057] FIG. 7 is a schematic diagram of generating a second drive signal shown by an exemplary embodiment. As shown in FIG. 7, a preset signal c is input to the positive input terminal of a second comparator A2, the reference carrier signal Fs is input to the negative input terminal of the second comparator A2, and a second drive signal output from the second comparator A2 is obtained, where the second drive signal is at a low level 0 and is used to control the target power device to be in a normally-off state.

[0058] The converter control method provided by the present disclosure can also control the high-frequency bridge arm included in the converter. In one embodiment, this control method can further include the step of generating a second type of drive signal for controlling and operating the high-frequency bridge arm based on a reference carrier signal and a reference signal. Here, there is a phase delay between the second type of drive signal and the first drive signal, and the delay phase is the preset phase described above. Exemplarily, the first drive signal is delayed by a preset phase compared to the second type of drive signal.

[0059] As shown in FIG. 5, the high-frequency bridge arm 10 includes a third bridge arm 101 and a fourth bridge arm 102. The third bridge arm 101 includes a fifth power device S5 and a sixth power device S6, and the fourth bridge arm 102 includes a seventh power device S7 and an eighth power device S8. The fifth power device S5 and the eighth power device S8 constitute a pair of tubes, and the sixth power device S6 and the seventh power device S7 constitute a pair of tubes.

[0060] In this embodiment, the second type of drive signal includes a third sub-drive signal for controlling and operating the first pair of tubes and a fourth sub-drive signal for controlling and operating the second pair of tubes. A specific embodiment of generating a second type of drive signal for controlling and operating the high-frequency bridge arm based on a reference carrier signal and a reference signal is to input the reference carrier signal to the negative input terminal of the third comparator, input the reference signal to the positive input terminal of the third comparator, and obtain the third sub-drive signal for controlling and operating the first pair of tubes output from the third comparator. Then, input the third sub-drive signal to the second inverter to obtain the fourth sub-drive signal for controlling and operating the second pair of tubes output from the second inverter.

[0061] When the first target power device is the first power device or the fourth power device, the first pair of paired tubes includes a fifth power device located on the upper bridge arm of the third bridge arm of the high-frequency bridge arm and an eighth power device located on the lower bridge arm of the fourth bridge arm of the high-frequency bridge arm. When the first target power device is the second power device or the third power device, the first pair of paired tubes includes a sixth power device located on the lower bridge arm of the third bridge arm of the high-frequency bridge arm and a seventh power device located on the upper bridge arm of the fourth bridge arm of the high-frequency bridge arm.

[0062] FIG. 8 is a schematic diagram showing a second type of drive signal generated according to an exemplary embodiment. As shown in FIG. 8, a reference carrier signal Fs is input to the negative input terminal of a third comparator A3, and a reference signal b is input to the positive input terminal of the third comparator A3 to obtain a third sub-drive signal for controlling and operating the first pair of paired tubes output from the third comparator A3. Also, the output terminal of the third comparator A3 is connected to the input terminal of a second inverter F2, that is, the third sub-drive signal is input to the second inverter F2 to obtain a fourth sub-drive signal for controlling and operating the second pair of paired tubes output from the second inverter F2.

[0063] In a possible embodiment, assuming that the target power devices in the normally-off state are the second power device S2 and the fourth power device S4, when the first target power device is the first power device S1, the first pair of paired tubes includes the fifth power device S5 and the eighth power device S8, and the second pair of paired tubes includes the sixth power device S6 and the seventh power device S7. When the first target power device is the third power device S3, the first pair of paired tubes includes the sixth power device S6 and the seventh power device S7, and the second pair of paired tubes includes the fifth power device S5 and the eighth power device S8.

[0064] In another possible embodiment, assuming that the target power devices in the normally-off state are the first power device S1 and the third power device S3, when the first target power device is the fourth power device S4, the first pair of paired tubes includes the fifth power device S5 and the eighth power device S8, and the second pair of paired tubes includes the sixth power device S6 and the seventh power device S7. When the first target power device is the second power device S2, the first pair of paired tubes includes the sixth power device S6 and the seventh power device S7, and the second pair of paired tubes includes the fifth power device S5 and the eighth power device S8.

[0065] FIG. 9 is a schematic diagram of a first drive signal shown by an exemplary embodiment. As shown in FIG. 9, there is a preset phase φ delay between the first sub-drive signal output from the first comparator A1 and the third sub-drive signal output from the third comparator A3, and there is a preset phase φ delay between the second sub-drive signal output from the first inverter F1 and the fourth sub-drive signal output from the second inverter F2. That is, the power devices corresponding to the primary side and the secondary side of the transformer unit 40 do not turn on simultaneously, and there is a certain phase delay. For example, assuming that the target power devices in the normally-off state are the first power device S1 and the third power device S3, the fifth power device S5 and the eighth power device S8 on the primary side of the transformer unit 40 and the fourth power device S4 on the secondary side of the transformer unit 40 do not turn on simultaneously, and there is a certain phase delay.

[0066] As shown in FIG. 9, the duty ratios of the first sub-drive signal to the fourth sub-drive signal are all 50%.

[0067] Exemplarily, as shown in FIG. 5, the transformer unit 40 includes a resonant inductance Ls, a primary-side resonant capacitor Cr of the transformer unit, a secondary-side resonant capacitor Cs of the transformer unit, and a transformer T. One end of the resonant inductance Ls is connected to the midpoint a of the third bridge arm 101 of the high-frequency bridge arm 10, and the other end is connected to the midpoint b of the fourth bridge arm 102 of the high-frequency bridge arm 10 through the primary side of the transformer T and the primary-side resonant capacitor Cr of the transformer. One end of the secondary side of the transformer T is connected to the midpoint c of the first bridge arm 501 in the rectifier circuit unit 50, and the other end of the secondary side of the transformer T is connected to the midpoint d of the second bridge arm 502 in the rectifier circuit unit 50 through the secondary-side resonant capacitor Cs of the transformer.

[0068] In combination with the converter shown in FIG. 5, it is assumed that the first power device S1 and the third power device S3 are in the normally-off state, the high-frequency bridge arm operates under the drive of the second type of drive signal, and the electric energy of the AC power grid is stored in the transformer unit 40. Then, when it is delayed by a preset phase, when the fourth power device S4 is turned on and the second power device S2 is turned off, the resonant electrical energy is stored in the transformer unit 40. When the second power device S2 is turned on and the fourth power device S4 is turned off, the negative electrode of the battery is connected to one end of the secondary side of the transformer T through the second power device S2 and the midpoint c, and the other end of the secondary side of the transformer T is connected to the positive electrode of the battery through the midpoint d and the body diode of the fourth power device S4, and the battery is charged using the electric energy of the AC power grid and the resonant electrical energy stored in the transformer unit 40. Thereby, the gain of the voltage output by the converter increases, and the charging efficiency is improved.

[0069] If the above technical solution is adopted, the target power device of the rectifier circuit unit is in the normally-off state, other power devices of the rectifier circuit unit are in the modulation state, and there is a phase delay between the drive signal used when modulating other power devices and the drive signal used when modulating the primary-side power device of the transformer unit. Thereby, the reverse flow of the battery's electricity amount is prevented, the reliability of the converter is improved, and the output voltage gain and charging efficiency are improved.

[0070] Also, the commercial frequency bridge arm can be controlled. Exemplarily, as shown in FIG. 5, the converter further includes a commercial frequency bridge arm 20, and this commercial frequency bridge arm 20 includes a ninth power device S9 and a tenth power device S10. The ninth power device S9 is located on the upper bridge arm of the commercial frequency bridge arm 20, and the tenth power device S10 is located on the lower bridge arm of the commercial frequency bridge arm 20. In the present disclosure, the ninth power device S9 and the tenth power device S10 can be controlled based on an alternating current signal.

[0071] Exemplarily, the period of the alternating current signal includes a positive half-cycle and a negative half-cycle. During the positive half-cycle, the tenth power device S10 is controlled to be turned on, and the ninth power device S9 is controlled to be turned off. During the negative half-cycle, the tenth power device S10 is controlled to be turned off, and the ninth power device S9 is controlled to be turned on.

[0072] Also, in FIG. 5, the alternating current transmission port 60 can include an alternating current power supply v g and a boost inductance. The boost inductance may be two independent inductances, denoted as L1 and L2. One end of L1 and one end of L2 are both connected to the positive terminal of the alternating current power supply v g The other end of L1 and the other end of L2 are respectively connected to the midpoint a of the first bridge arm 501 and the midpoint b of the second bridge arm 502. The alternating current power supply v gThe negative terminal of is connected to the midpoint e of the commercial frequency bridge arm 20. The third bridge arm, the fourth bridge arm, and the commercial frequency bridge arm form a single-phase staggered totem pole PFC topology structure, which can improve the conversion efficiency, reduce the current ripple of the input alternating current, and improve the quality of the input alternating current.

[0073] In the above, only the control method of the converter in the charging mode is described. In actual applications, the converter shown in FIG. 5 can also operate in the inverter mode. When the converter is operating in the charging mode, the preset range of the phase delay of the drive signals on the primary side and the secondary side of the transformer is 0 to 0.5, the output electrical signal pulsates at twice the AC frequency, and the preset phase delay at the zero crossing point of the voltage of the AC current signal reaches the maximum value. When the converter is operating in the inverter mode, the preset range of the phase delay of the drive signals on the primary side and the secondary side of the transformer is -0.15 to 0, the output electrical signal pulsates at twice the AC frequency, and the preset phase delay at the peak of the AC current signal reaches the maximum value. In this way, in both the charging mode and the inverter mode, the voltage gain can be increased throughout the entire cycle of the AC current signal.

[0074] Based on the same inventive concept, the present disclosure further provides a control device for a converter. FIG. 10 is a block diagram of a control device for a converter shown by an exemplary embodiment. The converter converts an input AC current signal into a DC current signal to charge a battery, and the converter includes a rectifier circuit unit. As shown in FIG. 10, when receiving a charging command, the control device 100 of the converter is configured to generate a reference carrier signal based on the current voltage value of the battery, the target voltage value of the battery, and the AC current signal. A first generation module 1001, and a second generation module configured to generate a first type of drive signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal, wherein the first type of drive signal is at least the target power device of the rectifier circuit unit A second generation module 1002 used to control the device to be in the normally-off state, and a first control module 1003 configured to control and operate the rectifier circuit unit using the first type of drive signal.

[0075] Optionally, the rectifier circuit unit includes a first bridge arm and a second bridge arm. The first bridge arm includes a first power device and a second power device. The second bridge arm includes a third power device and a fourth power device. The first power device is located on the upper bridge arm of the first bridge arm, the second power device is located on the lower bridge arm of the first bridge arm, the third power device is located on the upper bridge arm of the second bridge arm, and the fourth power device is located on the lower bridge arm of the second bridge arm. The target power device includes the first power device and the third power device, or the target power device includes the second power device and the fourth power device.

[0076] Optionally, the first type of drive signal includes a second drive signal for controlling the target power device to be in a normally-off state and a first drive signal for controlling and operating other power devices other than the target power device of the rectifier circuit unit. The second generation module 1002 may include a first generation sub-module configured to generate a first drive signal for controlling and operating other power devices other than the target power device of the rectifier circuit unit based on the reference carrier signal and a preset duty ratio of the drive signal.

[0077] Optionally, other power devices other than the target power device of the rectifier circuit unit include a first target power device and a second target power device. The first generation sub-module generates a reference signal based on the reference carrier signal and a preset duty ratio of the drive signal. The amplitude of the reference signal does not change with the phase of the alternating current signal. The reference signal is input to the positive input terminal of a first comparator, and the reference carrier signal is phase-shifted by a preset phase and then input to the negative input terminal of the first comparator to obtain a first sub-drive signal for controlling and operating the first target power device output from the first comparator. The first sub-drive signal is input to a first inverter, and it is configured to obtain a second sub-drive signal for driving and operating the second target power device output from the first inverter.

[0078] Optionally, the second generation module 1002 may further include a second generation sub-module configured to input a preset signal to the positive input terminal of a second comparator and input the reference carrier signal to the negative input terminal of the second comparator to obtain a second drive signal output from the second comparator. The second drive signal is used for controlling the target power device to be in a normally-off state.

[0079] Optionally, the converter further includes a high-frequency bridge arm, and a control device 100 of the converter is a third generation module configured to generate a second type of drive signal for controlling and operating the high-frequency bridge arm based on the reference carrier signal and the reference signal, and the third generation module is such that the first drive signal is delayed by a preset phase from the second type of drive signal, and further includes a second control module configured to control and operate the high-frequency bridge arm using the second type of drive signal.

[0080] Optionally, the high-frequency bridge arm includes a first pair of tubes and a second pair of tubes, the second type of drive signal includes a third sub-drive signal for controlling and operating the first pair of tubes and a fourth sub-drive signal for controlling and operating the second pair of tubes, the third generation module inputs the reference carrier signal to the negative input terminal of a third comparator, inputs the reference signal to the positive input terminal of the third comparator, obtains the third sub-drive signal for controlling and operating the first pair of tubes output from the third comparator, inputs the third sub-drive signal to a second inverter, and is configured to obtain the fourth sub-drive signal for controlling and operating the second pair of tubes output from the second inverter. When the first target power device is the first power device or the fourth power device, the first pair of tubes includes a fifth power device located on the upper bridge arm of the third bridge arm of the high-frequency bridge arm and an eighth power device located on the lower bridge arm of the fourth bridge arm of the high-frequency bridge arm. When the first target power device is the second power device or the third power device, the first pair of tubes includes a sixth power device located on the lower bridge arm of the third bridge arm of the high-frequency bridge arm and a seventh power device located on the upper bridge arm of the fourth bridge arm of the high-frequency bridge arm.

[0081] Optionally, the period of the alternating current signal includes a positive half-cycle and a negative half-cycle, the converter further includes a commercial frequency bridge arm, the commercial frequency bridge arm includes a ninth power device and a tenth power device, the ninth power device is located on the upper bridge arm of the commercial frequency bridge arm, the tenth power device is located on the lower bridge arm of the commercial frequency bridge arm, and the control device 100 of the converter includes a third control module configured to control the tenth power device to turn on or control the ninth power device to turn off within the positive half-cycle, and a fourth control module configured to control the tenth power device to turn off and control the ninth power device to turn on within the negative half-cycle.

[0082] Regarding the device of the above embodiment, the specific manner in which each module thereof executes operations has already been described in detail in the embodiments related to the method, and thus will not be described in detail here.

[0083] The present disclosure further provides a computer-readable storage medium storing computer program instructions, and when the program instructions are executed by a processor, the steps of the converter control method provided by the present disclosure are realized.

[0084] Based on the same inventive concept, the present disclosure further provides a control device including a processor and a memory for storing instructions executable by the processor, and the processor is configured to realize the steps of the converter control method provided by the present disclosure by executing the instructions.

[0085] Exemplarily, the control device may be a controller.

[0086] Based on the same inventive concept, the present disclosure further provides an in-vehicle charger including a converter and a controller provided by the present disclosure.

[0087] Based on the same inventive concept, the present disclosure further provides a vehicle, which includes a battery and an in-vehicle charger provided by the present disclosure, and the in-vehicle charger charges the battery.

[0088] FIG. 11 is a block diagram of a vehicle shown by an exemplary embodiment. For example, the vehicle 600 may be a hybrid vehicle, or may be a non-hybrid vehicle, an electric vehicle, a fuel cell vehicle, or other types of vehicles. The vehicle 600 may be an autonomous vehicle, a semi-autonomous vehicle, or a non-autonomous vehicle.

[0089] Referring to FIG. 11, the vehicle 600 can include various subsystems, such as an infotainment system 610, a perception system 620, a decision-making and control system 630, a drive system 640, and a computing platform 650. Here, the vehicle 600 may further include more subsystems or fewer subsystems, and each subsystem can include a plurality of components. Also, the interconnections between each subsystem and between each component of the vehicle 600 can be realized by wire or wirelessly. Also, the vehicle 600 can further include an in-vehicle charger.

[0090] In some embodiments, the infotainment system 610 can include a communication system, an entertainment system, a navigation system, and the like.

[0091] The perception system 620 can include several sensors for sensing information about the environment around the vehicle 600. For example, the perception system 620 can include a global positioning system (the global positioning system may be a GPS system, or may be a Beidou system or other positioning systems), an inertial measurement unit (IMU), a lidar, a millimeter wave radar, an ultrasonic radar, and an imaging device.

[0092] The decision control system 630 can include a computing system, a vehicle overall control device, a steering system, an accelerator, and a braking system.

[0093] The drive system 640 can include an assembly that provides motive motion to the vehicle 600. In one embodiment, the drive system 640 can include an engine, an energy source, a transmission system, and wheels. The engine can be one or a combination of an internal combustion engine, an electric motor, and a pneumatic engine. The engine can convert the energy supplied from the energy source into mechanical energy.

[0094] Some or all of the functions of the vehicle 600 are controlled by the computing platform 650. The computing platform 650 can include at least one processor 651 and a memory 652, and the processor 651 can execute instructions 653 stored in the memory 652.

[0095] The processor 651 can be any conventional processor such as a commercially available CPU. The processor can also include a Graphic Process Unit (GPU), a Field Programmable Gate Array (FPGA), a System on Chip (SOC), an Application Specific Integrated Circuit (ASIC), or a combination thereof.

[0096] The memory 652 may be implemented by any type of volatile or non-volatile storage device, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk, or a combination thereof.

[0097] In addition to the instructions 653, the memory 652 can also store data such as road maps, route information, the position, direction, speed of the vehicle, etc. The data stored in the memory 652 can be used by the computing platform 650.

[0098] In an embodiment of the present disclosure, the processor 651 can execute the instructions 653 to complete all or part of the steps of the above converter control method.

[0099] In another exemplary embodiment, a computer program executable by a programmable device is further provided, and this computer program has a code portion for executing the above converter control method when executed by the programmable device.

[0100] Also, in this specification, the term "exemplary" is used to denote serving as an illustration, an example, or a drawing. Any aspect or design described as "exemplary" in this specification is not necessarily understood to be advantageous as compared to other aspects or designs. Rather, the exemplary purpose of using the term is to present the concept in a concrete manner. As used in this specification, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, "X applies A or B" is intended to represent any of the natural inclusive arrangements unless otherwise specified or clear from the context. That is, "X applies A or B" is satisfied in any of the above examples when X applies A, X applies B, or X applies both A and B. Further, unless explicitly specified in the singular or directed from the context, the articles "a" and "an" used in this application and the appended claims are generally understood to represent "one or more".

[0101] Similarly, although the present disclosure has been illustrated and described with respect to one or more implementations, those skilled in the art will envision equivalent modifications and variations after reading and understanding the present specification and drawings. The present disclosure includes all such modifications and variations and is limited only by the scope of the claims. In particular, with respect to the various functions performed by the components (e.g., elements, resources, etc.) described above, unless otherwise specified, the terms used to describe such components are intended to correspond to any component (functionally equivalent) that performs the specific functions of the described components, even if not structurally equivalent to the disclosed structure. Also, a particular feature of the present disclosure may be disclosed with respect to only one of several implementations, but such a feature can be combined with one or more other features of one or more other implementations so as to be desirable and advantageous for any given or particular application. Further, such terms are intended to be inclusive in a manner similar to the term "comprising" for the specific embodiments or claims used herein, "possessing", "having", "including", or variations thereof.

[0102] After considering the specification and practicing the technical solutions disclosed herein, those skilled in the art can easily envision other embodiments of the present disclosure. The present disclosure is intended to cover any modification, use, or adaptive change of the present disclosure, and these modifications, uses, or adaptive changes follow the general principles of the present disclosure and include common general knowledge or commonly used technical means in the technical field not disclosed in the present disclosure. The specification and examples are to be regarded as merely illustrative, and the true scope and spirit of the present disclosure are pointed out by the appended claims.

[0103] It should be noted that the present disclosure is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

[0104] It should be understood that, unless otherwise specified, the features of several embodiments of the various disclosures described herein may be combined with each other. As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more thereof, and similarly, "at least one of..." includes any one of the associated listed items and any combination of any two or more thereof.

[0105] In this specification, terms such as "first", "second", "third", etc. can be used to describe various components, members, regions, layers, or sections, but these components, members, regions, layers, or sections are not limited to these terms. Rather, these terms are only used to distinguish one component, member, region, layer, or section from another. Thus, without departing from the teachings of each example, the first component, member, region, layer, or section referred to in the examples described herein could also be referred to as the second component, member, region, layer, or section. Also, the terms "first" and "second" are used for illustrative purposes only and are not intended to indicate or imply relative importance or implicitly indicate the number of the indicated technical features. Thus, features limited to "first" and "second" can include at least one of the said features explicitly or implicitly. In this specification, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless there is a specific and clear limitation.

Claims

1. A method for controlling a converter, the converter converting an input AC signal into a DC signal to charge a battery, the converter including a rectifier circuit unit, when receiving a charging command, generating a reference carrier signal according to a current voltage value of a battery, a target voltage value of the battery, and the AC signal; generating a first type of driving signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal, the first type of driving signal being used to control at least a target power device of the rectifier circuit unit to be in a normally-off state; using the first type of driving signal to control and operate the rectifier circuit unit; A method for controlling a converter comprising:

2. the rectifier circuit unit includes a first bridge arm and a second bridge arm, the first bridge arm includes a first power device and a second power device, the second bridge arm includes a third power device and a fourth power device, the first power device is located on an upper bridge arm of the first bridge arm, the second power device is located on a lower bridge arm of the first bridge arm, the third power device is located on an upper bridge arm of the second bridge arm, and the fourth power device is located on the lower bridge arm of the second bridge arm, 2. The method of claim 1, wherein the target power devices include the first power device and the third power device, or the target power devices include the second power device and the fourth power device.

3. the first type of drive signal includes a second drive signal for controlling the target power device to be in a normally-off state, and a first drive signal for controlling and operating other power devices of the rectifier circuit unit than the target power device, generating a first type of drive signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal; 3. The converter control method according to claim 2, further comprising a step of generating a first drive signal for controlling and operating a power device other than the target power device of the rectifier circuit unit based on a duty ratio of the reference carrier signal and a preset drive signal.

4. the power devices other than the target power device of the rectifier circuit unit include a first target power device and a second target power device; A step of generating a first drive signal for controlling and operating a power device other than the target power device of the rectifier circuit unit based on a duty ratio of the reference carrier signal and a drive signal that is set in advance, generating a reference signal based on the reference carrier signal and a preset duty ratio of the drive signal, the amplitude of the reference signal not changing depending on the phase of the AC current signal; inputting the reference signal to a positive input terminal of a first comparator, and inputting the reference carrier signal to a negative input terminal of the first comparator after phase-shifting the reference signal by a preset phase, thereby obtaining a first sub-driving signal for controlling and operating the first target power device outputted from the first comparator; inputting the first sub-driving signal to a first inverter to obtain a second sub-driving signal output from the first inverter for driving and operating the second target power device; 4. A method for controlling a converter according to claim 3, comprising:

5. generating a first type of drive signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal; 4. The converter control method of claim 3, further comprising the steps of: inputting a preset signal to a positive input terminal of a second comparator, inputting the reference carrier signal to a negative input terminal of the second comparator, and obtaining a second drive signal output from the second comparator, the second drive signal being used to control the target power device to be in a normally-off state.

6. the converter includes a high frequency bridge arm; generating a second type of driving signal for controlling and operating the high frequency bridge arm based on the reference carrier signal and the reference signal, the first driving signal being delayed by a predetermined phase from the second type of driving signal; using the second type of drive signal to control and operate the high frequency bridge arm; 5. A method for controlling a converter as claimed in claim 4, comprising:

7. The high-frequency bridge arm includes a first set of paired tubes and a second set of paired tubes, and the second type of driving signal includes a third sub-driving signal for controlling and operating the first set of paired tubes and a fourth sub-driving signal for controlling and operating the second set of paired tubes; generating a second type of driving signal for controlling and operating the high frequency bridge arm based on the reference carrier signal and the reference signal; inputting the reference carrier signal into a negative input terminal of a third comparator, inputting the reference signal into a positive input terminal of the third comparator, and obtaining a third sub-driving signal for controlling and operating the first set of paired tubes outputted from the third comparator; inputting the third sub-driving signal into a second inverter to obtain a fourth sub-driving signal output from the second inverter for controlling and operating the second set of paired tubes; Including, 7. The converter control method according to claim 6, wherein when the first target power device is the first power device or the fourth power device, the first set of paired tubes includes a fifth power device located on an upper bridge arm of a third bridge arm of the high-frequency bridge arm and an eighth power device located on a lower bridge arm of a fourth bridge arm of the high-frequency bridge arm; when the first target power device is the second power device or the third power device, the first set of paired tubes includes a sixth power device located on a lower bridge arm of the third bridge arm of the high-frequency bridge arm and a seventh power device located on an upper bridge arm of the fourth bridge arm of the high-frequency bridge arm.

8. a period of the AC signal includes a positive half period and a negative half period; the converter includes a power frequency bridge arm, the power frequency bridge arm includes a ninth power device and a tenth power device, the ninth power device is located on an upper bridge arm of the power frequency bridge arm, and the tenth power device is located on a lower bridge arm of the power frequency bridge arm; controlling the tenth power device to be turned on and the ninth power device to be turned off during the positive half cycle; controlling the tenth power device to be turned off and the ninth power device to be turned on during the negative half cycle; A method for controlling a converter according to any one of claims 1 to 7, comprising:

9. generating a reference carrier signal based on a current voltage value of a battery, a target voltage value of the battery, and the AC current signal when the charging command is received; obtaining a target current value based on a difference between a current voltage value of a battery and a target voltage value of the battery; obtaining a frequency control parameter based on the target current value and a current value of the AC current signal, the frequency control parameter being capable of indicating a frequency of a reference carrier signal to be generated; generating a reference carrier signal based on the frequency control parameter; A method for controlling a converter according to any one of claims 1 to 5, comprising:

10. A control device for a converter, the converter converting an input AC signal into a DC signal to charge a battery, the converter including a rectifier circuit unit, A first generating module configured to generate a reference carrier signal based on a current voltage value of a battery, a target voltage value of the battery, and the AC current signal when a charging command is received; A second generating module configured to generate a first type of driving signal for controlling and operating the rectifier circuit unit based on at least the reference carrier signal, the first type of driving signal being used to control at least a target power device of the rectifier circuit unit to be in a normally-off state; a first control module configured to control and operate the rectifier circuit unit using the first type of drive signal; A control device for a converter.

11. A processor; a memory for storing instructions executable by a processor; A control device, wherein the processor is configured to implement the steps of the method for controlling a converter according to any one of claims 1 to 7 by executing the instructions.

12. An on-board charger comprising a converter and a control device according to claim 11.

13. A vehicle comprising a battery and an on-board charger according to claim 12.

14. A computer readable storage medium having computer program instructions stored thereon, comprising: A computer readable storage medium, wherein the computer program instructions, when executed by a processor, cause the steps of the method according to any one of claims 1 to 7 to be realized.

15. A computer program which, when executed by a processor, implements the steps of the method according to any one of claims 1 to 7.

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