Inverter for an electric drive unit

Abstract

The present invention relates to an inverter for converting Direct Current (DC) into Alternating Current (AC) to power an electric drive unit (EDU). The invention further relates to an inverter, a method in an inverter, a control system for controlling an inverter, a vehicle comprising an inverter and computer readable instructions for controlling an inverter. A method (200) in an inverter for converting a direct current, DC, into an alternating current, AC, to power an electric drive unit, EDU, in a vehicle, comprises iteratively adjusting (202) an output current from the inverter, dependent on an input DC bus voltage applied to the inverter, to maintain voltage overshoots output by the inverter caused by a plurality of switching events in the inverter below a maximum operating voltage of the inverter.

Description

[0001] INVERTER FOR AN ELECTRIC DRIVE UNIT

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to an inverter for converting Direct Current (DC) into Alternating Current (AC) to power an electric drive unit (EDU). Embodiments of the invention relate to an inverter, a method in an inverter, a control system for controlling an inverter, a vehicle comprising an inverter and computer readable instructions for controlling an inverter.

[0004] BACKGROUND

[0005] Inverters are used in electric vehicles including plug-in and hybrid electric vehicles to power electric drive units (EDUs). In such vehicles, the DC battery voltage is converted into an AC voltage profile using the inverter. The input voltage from the battery is converted to AC by turning switches (such as Silicon Carbide, SiC, switches) on and off in a repeating alternating pattern in the inverter, in order to create the sinusoidal, AC, output voltage.

[0006] SUMMARY OF THE INVENTION

[0007] As noted above, SiC switches are used to convert the input DC voltage from the battery of the vehicle into an output AC voltage. Figure 1 shows the output voltage (V) on the left-hand y-axis, and current profile (Arms) on the right-hand y-axis, over time (on the x-axis) for an example inverter when a switch in the inverter is switch from “on” to “off. For the example inverter illustrated in Figure 1 , the current 102 illustrated by the dash-dot line turns from “on” (~500 Arms) to “off’ (0 Arms) and the voltage rises from OV to ~850V. During the switching event (corresponding to the time period between the vertical thick dashed lines) overshoot occurs. In this example, the voltage 104 is meant to rise from 0 V to the bus voltage indicated by the line 108 (e.g. 838 V in the example). However, in reality, the voltage overshoots due to the inductance of the system. The power module is designed to withstand a maximum voltage (indicated by the line 106) of 1200 V in this example, and exceeding 1200V can cause damage to the components and thus rapid life consumption of the module. As such, the maximum voltage, (the level of which will depend on the hardware components in the particular inverter), is considered a hard limit. It will be appreciated that the particular voltages above are merely examples, and that the maximum voltage of an inverter will be dependent on its particular components and configuration.

[0008] The overshoot can be reduced by lowering the gradient of the transition (e.g. slower transition between the “on” and “off’ states). A slower transition can be obtained by changing the internal components of the inverter, or changing the sinusoidal profile of the output voltage, so this is not generally preferred.

[0009] Therefore, in traditional systems, the output current is therefore fixed or limited at a level so that the voltage overshoot during switching events does not exceed the threshold maximum voltage 108. However, this reduction of the output voltage 108 of the inverter in turn reduces the torque available to the EDU of the vehicle (the output current of the inverter is proportional to the EDU torque). Thus, the potential torque of the vehicle is effectively limited due to the need to protect the inverter from voltage overshoot caused by switching events. It is an object of embodiments herein to address this problem, in order to obtain high levels of torque whilst protecting the internal components of the inverter.

[0010] It has been recognised herein that the potential damage caused by voltage overshoots is dependent on the state of charge of the battery, with overshoots causing most damage at high battery levels (e.g. just after charging). At higher battery voltages, the maximum point / voltage reached during the overshoot is also correspondingly higher. In embodiments herein, it is therefore proposed to dynamically set the output current level responsive to the input DC bus voltage from the battery. In this way, the current level can be dynamically maintained at, or near to, the maximum possible level, without damaging the inverter, and thus maintaining high levels of torque in the EDU. In this way, the current does not have to be unnecessarily limited, beyond the level to protect the inverter components. Furthermore, embodiments herein enable vehicles to have larger battery packs (more battery = higher voltage) without the need to change the Power Electronic hardware, minimising change and potential re-design costs.

[0011] According to an embodiment herein, there is a method performed by a controller in an inverter, the inverter being for converting a direct current, DC, into an alternating current, AC, to power an electric drive unit, EDU, in a vehicle, the method comprising: controlling the inverter to iteratively adjust an output current of the inverter, dependent on an input DC bus voltage applied to the inverter, to maintain voltage overshoots output by the inverter below a maximum operating voltage of the inverter, the voltage overshoots being caused by a plurality of switching events in the inverter.

[0012] In some embodiments, the step of the step of controlling the inverter to iteratively adjust the output current further comprises maximising the output current of the inverter while maintaining the voltage overshoots below the maximum operating voltage of the inverter. Thus, in this way the current can be optimised so as to maintain the output voltage of the inverter as high as possible (thus leading to highest possible torque), while maintaining the voltage overshoots below the maximum operating voltage of the inverter to prevent damage.

[0013] In some embodiments, the step of iteratively adjusting the output current comprises increasing the output current in response to a drop in the DC bus voltage. Thus, in other words, the current may be set at a first level when the DC bus voltage is at a first voltage level, and the current may be set to a second level when the DC bus voltage is at a second voltage level. In such an example, the second (current) level is greater than the first (current) level and the first voltage level is higher than the second voltage level. When the DC bus voltage drops, the maximum voltage in an overshoot also reduces in magnitude. Thus, the current can be safely increased, resulting in higher torque for the EDU, without the voltage overshoots exceeding the maximum operating voltage of the inverter.

[0014] In some embodiments, the output current is increased according to a stepped profile dependent on a magnitude of the drop in the DC bus voltage. A stepped profile is an efficient way to increase the current, without the need to continuously monitor the battery voltage. In some embodiments, the step of controlling the inverter to iteratively adjust the output current comprises setting the output current to be inversely linearly proportional to the DV bus voltage.

[0015] In some embodiments, the method comprises iteratively adjusting the output current according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained at the maximum operating voltage of the inverter. In this way the DC bus voltage can be monitored and the current output by the inverter can be set dynamically, so as to maintain the voltage overshoots at a near constant level, thus maximising the torque available to the EDU.

[0016] In some embodiments, the method comprises iteratively adjusting the output current according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained above a threshold voltage, the threshold voltage being less than the maximum operating voltage of the inverter. In this way, the torque can be maintained at high levels, dependent on the DC bus voltage from the battery.

[0017] In some embodiments, the method comprises controlling the inverter to decrease the output current in response to an increase in the DC bus voltage. An increase in DC bus voltage, e.g. due to charging of the battery results in higher voltage overshoots. Thus, decreasing the output current following battery charging ensures that the voltage overshoots do not exceed the maximum operating voltage of the inverter, and thus protects the inverter.

[0018] According to an embodiment, there is a method as in any of the clauses above, wherein the controller is a software module in the inverter. In such embodiments, the step of the step of controlling the inverter to iteratively adjusting the input output current supplied to from the inverter comprises receiving a measurement of the DC bus voltage; determining an input output current level to be applied output by to the inverter, dependent on the DC bus voltage; and sending an instruction to a power module to set the input output current level to of the inverter to the determined input output current level. In this way, the software module can dynamically adjust the output current from the inverter, according to the DC bus voltage supplied by the battery.

[0019] In embodiments herein, a switching event comprises a switch in the inverter being switched from an on position to an off position or from an off position to an on position. It is the switching events that result in voltage overshoot.

[0020] According to another embodiment herein, there is an inverter for converting a direct current, DC, into an alternating current, AC, to power an Electric Vehicle. The inverter is configured to iteratively adjust an output current of the inverter, dependent on a DC bus voltage applied to the inverter, to maintain voltage overshoots below a maximum operating voltage of the inverter, the voltage overshoots being caused by a plurality of switching events in the inverter.

[0021] According to another embodiment herein there is a control system for controlling an inverter of a vehicle. The control system comprises one or more processors collectively configured to send an instruction to the inverter to operate according to the method embodiments above. According to another embodiment herein there is a vehicle comprising the inverter of the inverter embodiments above. In some embodiments, the vehicle comprises the control system of the previous embodiment. Vehicles comprising the inverters described herein advantageously are able to maintain the maximum possible torque at all battery levels.

[0022] According to another embodiments there are computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the method of the method embodiments above.

[0023] Within the scope of this application it is expressly intended that the various embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner.

[0024] BRIEF DESCRIPTION OF THE DRAWINGS

[0025] One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0026] Figure 1 shows example current and voltage profiles during a switching event in an inverter;

[0027] Figure 2a shows an example method in an inverter according to embodiments herein;

[0028] Figure 2b shows an example control system for controlling an inverter according to some embodiments herein; Figure 3 shows an example inverter according to some embodiments herein;

[0029] Figure 4 shows an example relationship for setting the output current from the inverter according to some embodiments herein; and

[0030] Figure 5 shows a vehicle in accordance with an embodiment of the invention.

[0031] DETAILED DESCRIPTION

[0032] As described above, inverters are used in electric and hybrid-electric vehicles to convert DC voltage from the vehicle’s battery into AC voltage. The inverters contain one or more switches that turn the current input into the inverter from the battery “on” and “off” in a sinusoidal pattern. Such switching events in an inverter result in voltage overshoot, as shown in Figure 1 and described in the Summary section above. Voltage overshoot can damage the components of the inverter, and result in failure. There is thus a hard limit set on an inverter, that limits the output voltage level and thus the amount of overshoot that can be tolerated. The voltage can be kept below the threshold level by setting the current at a lower level, but this reduces the resulting torque available to the electric drive unit of the vehicle as inverter AC current is proportional to EDU torque. The amount of current an inverter can push is dictated by the DC bus voltage supplied to the inverter. If the voltage is too high, the amount of current now needs to be limited.

[0033] It has been recognised by the inventors of the disclosure herein, that the peak voltage overshoot reached during to switching events in an inverter is not linear. In particular, the voltage overshoot reaches the highest levels when the battery is fully charged, but the maximum voltage reached progressively lowers as the charge of the battery runs down. Therefore, in order to maximise the available torque while protecting the internal components of the inverter, embodiments herein propose to change the output current level from the inverter, dependent on the input voltage to the inverter supplied by the vehicle battery. In embodiments herein, the output current level from the inverter is therefore iteratively adjusted, dependent on the battery voltage, to maintain the voltage overshoots output by the inverter below a maximum operating voltage of the inverter. In this way, using an iterative approach (e.g. rather than a fixed current), the current can be set so as to protect the components of the inverter, while also keeping the current as high as possible, thus achieving the maximum possible torque from the electric drive unit. Thus, rather than having the current limited by the current capability at peak battery voltage, the current capability now varies dependent on the DC bus voltage read by the inverter. This dynamic adjustment of current capability enables the current to be lifted once the voltage on the DC bus has dropped, leading to faster 0-1 OOkph times. In this way, a voltagedependent inverter current can be set for 0-100 kph robustness. Embodiments herein also enable the vehicle to have larger battery packs (more battery = higher voltage) without the need to change the power electronic hardware, thus minimising change and cost.

[0034] Turning now to Figure 2a, which shows a method 200 performed by a controller 308 in an inverter, the inverter being for converting a direct current (DC) into an alternating current, (AC) to power an electric drive unit, EDU, in a vehicle. The method may be performed by the inverter itself, for example, the inverter may comprise a controller 308 such as a software module comprising one or more processors that are configured to control the inverter and perform the method 200.

[0035] In other embodiments, the inverter may be controlled by a controller that is separate or external to the inverter itself. In such embodiments, the controller may comprise one or more processors collectively configured to send one or more instructions to the inverter to cause the inverter to operate according to the method 200. A controller is described below with respect to Figure 2b.

[0036] Turning back to the method 200, in brief, in a first step 202, the method 200 comprises controlling the inverter to iteratively adjust an output current of the inverter, dependent on an input DC bus voltage applied to the inverter, to maintain voltage overshoots output by the inverter caused by a plurality of switching events in the inverter below a maximum operating voltage of the inverter. In more detail, the vehicles herein may be any type of vehicle that is fully or partly electric, e.g. a fully electric, or hybrid-electric vehicle. Vehicles include passenger vehicles such as cars, vans, lorries, or any other type of vehicle. Such vehicles have electric drive units (EDUs) that provide torque to the wheel axes to propel the vehicle.

[0037] The EDU has an inverter. The inverter is for converting the DC current from the battery into AC current (or AC to DC for charging). The skilled person will be familiar with inverters, which are used to convert DC current into AC current by means of one or more switches. A simplified representation of an inverter 300 is shown in Fig. 3 which shows the vehicle battery 302, that feeds the inverter circuitry 304. The inverter circuitry 304 comprises at least one switch (not illustrated). Such switches may, for example, be Silicon Carbide, SiC, switches, although this is merely an example, and other switches are equally possible. The switches are repeatedly switched on and off in the inverter in order create a sinusoidal (e.g. AC) output voltage from the inverter at 306 which is used to power the induction motor of the vehicle. It will be appreciated that the inverter circuitry 304 may take many forms and that there are a wide range of different types of inverters that the method herein may be applied to. The inverter may further comprise a controller 308 which is configured to control the circuitry 304 to produce an output voltage from the inverter according to the principles described herein (e.g. the controller 308 may perform the method 200).

[0038] As described above, when a switch is turned off and current is prevented from flowing, this results in a rapid increase in voltage in the inverter. The voltage rises rapidly and then falls again to a flat stable positive level. This pattern is referred to as a “voltage overshoot”. The magnitude (or size) of the overshoot depends on the level of the input current to the inverter, (e.g before the switch is turned off), and the rapidity of the switching event (e.g. whether the current is switched off abruptly, or whether there is a slower reduction in the current).

[0039] The output current of the inverter is dictated (e.g. set) according to the DC bus voltage supplied to the inverter by the vehicle battery 302. The inverter 300 has a maximum operating voltage, and if the voltage across the inverter rises above said maximum operating voltage, then this results in damage to the components of the inverter (thus reducing the lifetime of the inverter module).

[0040] Thus, if the DC bus voltage from the battery 302 is too high, the output current needs to be limited, or else it will result in voltage overshoots within the inverter that exceed the maximum operating voltage of the inverter.

[0041] Herein, the output current of the inverter circuitry 304, is thus adjusted dependent on the level of the input DC bus voltage applied to the inverter (e.g. dependent on the battery 302 voltage).

[0042] In some embodiments, in step 202, the method 200 comprises increasing the output current in response to a drop in the DC bus voltage (e.g. a drop in the vehicle battery voltage). Thus, in other words, the current may be set at a first level when the DC bus voltage is at a first voltage level, and the current may be set to a second level where the DC bus voltage is set at a second voltage level. In such an example, the second (current) level is greater than the first (current) level and the first voltage level is higher than the second voltage level. The output current can be increased because, due to the drop or reduction in bus voltage as the battery drains, the voltage overshoots are lower in magnitude.

[0043] The output current may be increased in different ways, e.g. according to different profiles. For example, step 202 may comprise increasing the current according to a stepped profile, dependent on a magnitude of the drop in the DC bus voltage. This is illustrated in Figure 4 which shows a graph of Maximum Battery Voltage (x-axis) vs Maximum EDU Torque (y-axis. This graph shows an example of how the maximum current output from the inverter 402 might be set as a function of the Maximum Battery DC voltage (x-axis), for an example inverter, in a stepped manner according to profile 402, whereby the output current from the inverter is changed in increments in response to a drop in battery voltage.

[0044] It will be appreciated however that a stepped profile is merely an example and that other profiles are equally possible, for example, a linear profile as indicated by the dashed line 404 in Figure 4, whereby the current is set to be inversely linearly proportional to the DC bus voltage. In other words, the step of iteratively adjusting 202 the output current may comprise setting the output current from the inverter to be inversely linearly proportional to the DV bus voltage. In some embodiments, the output current is maximised, while maintaining the voltage overshoots below the maximum operating voltage of the inverter. In other words, the output current is limited enough to prevent the voltage overshoots from exceeding the maximum operating voltage of the inverter while maintaining the peak voltage of each overshoot at (or near) the maximum operating voltage of the inverter. This may be performed in an iterative manner e.g. in a feedback loop, whereby the battery voltage (e.g. the DC bus voltage input to the inverter) is measured and the current input to the inverter limited, according to the measured battery voltage. In this way, the peaks of the voltage overshoots are kept close (e.g. within a threshold) to the maximum operating voltage, leading to maximum current flow and maximum torque production for the EDU.

[0045] In some embodiments, the output current may be iteratively adjusted according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained at (or close to) the maximum operating voltage of the inverter.

[0046] In other embodiments, the output current may be iteratively adjusted according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained above a threshold voltage, the threshold voltage being less than the maximum operating voltage of the inverter.

[0047] As noted above, the overshoots increase in magnitude when the DC bus voltage is high. Thus, the overshoots are higher in magnitude following charging of the battery (and highest when the battery is fully charged). It will therefore be appreciated that the current can be decreased in response to charging of the vehicle battery. For example, the method 200 may further comprise decreasing the output current from the inverter in response to an increase in the DC bus voltage. In this way, the output current is set responsive to the battery voltage.

[0048] The method 200 may be implemented in various different ways. For example, the inverter may have a controller 308. The controller 308 may comprise a software module in the inverter itself. Such a software module may perform the method 200 above, and iteratively adjust the output current from the inverter according to any of the processes described above. The software module may receive a measurement of the DC bus voltage (e.g. from a potentiometer, or other sensor), and then determine an output current level, dependent on the DC bus voltage. For example, the software module may use a relationship such as the stepped, or linear relationships 402; 404 illustrated in Fig. 4, (or an equation encapsulating said relationships) to determine an appropriate output current for the measured voltage of the battery. The software module may the send an instruction to a power module to set the input current level (or limit the input current from the battery) to ensure the output current from the inverter is at a safe level.

[0049] As noted above, the method 200 may also be performed by a control system that sends signals to the inverter to control the inverter. An example control system 250 is illustrated in Figure 2b. In this example, the control system 250 comprises one controller 260, although it will be appreciated that this is merely illustrative. The controller 260 comprises processing means 252 and memory means 254. The processing means 252 may be one or more electronic processing devices (e.g. one or more processors) which operably executes computer- readable instructions 256 (e.g. computer code). The memory means 254 may be one or more memory devices. The memory means 254 is electrically coupled to the processing means 252. The memory means 254 is configured to store the computer-readable instructions 265, and the processing means 252 is configured to access the memory means 254 and execute the computer readable instructions 265 stored thereon. The computer readable instructions comprise instructions (e.g. computer code) that when executed by the processor 252 cause the processor to perform the method 200.

[0050] The controller 260 comprises an input means 258 and an output 259. The input means 258 may comprise an electrical input of the controller 260. The output means 259 may comprise an electrical output of the controller. The input 258 may be arranged (e.g. configured or operative) to receive a signal comprising a measurement of the input voltage to the inverter from a sensor such as a potentiometer or other voltage reader. The output 259 is arranged to output a control signal 155 to cause the inverter to output the appropriate current from the inverter.

[0051] Turning now to Figure 5 which shows a passenger vehicle 500 according to some embodiments herein. The passenger vehicle 500 comprises a battery 302, an inverter 300, a control system 250 for controlling the inverter 300 and an EDU 500 connected to the axle of the vehicle for propelling the vehicle forward. As noted above, the controller 250 is configured to perform the method 200 described above and control the output current from the inverter, dependent on the input DC bus voltage applied to the inverter.

[0052] Turning now to other embodiments, it will be appreciated that the method 200 may be embodied in a computer program. For example, a computer program product may comprise a computer readable medium, the computer readable medium having computer readable code embodied thereon. The computer readable code can be configured such that, on execution by a suitable computer or processor, the computer or processor is caused to perform the method or methods described herein (such as the method 200).

[0053] A computer program may take different forms, for example, source code, compiled code, executable code, or any other type of code. It will be appreciated that the source code of computer programs may be written in a wide variety of different programming languages, and may take different architectural designs. For example, the functionality described herein may be split across various different sub-routines. Furthermore, the skilled person will appreciate that many different ways of splitting the functionality between the different subroutines will be possible. The sub-routines may be stored together in one executable file to form a self- contained program. Furthermore, computer programs may call external and / or standard libraries of computer code for performing certain sub-tasks associated with the functionality described herein.

[0054] In another embodiment, there is a computer program product comprising non-transitory computer readable media, having stored thereon a computer program as described above. Examples of computer readable media include, but are not limited to: ROM, such as a CD ROM, a semi-conductor ROM or a magnetic recording medium such as a hard disk.

[0055] In another embodiment, there is a carrier containing a computer program. Examples of carriers include but are not limited to an electronic signal, optical signal, radio signal, computer storage medium, or similar. The carrier of a computer program may be any entity or device (e.g. hardware) capable of carrying the program. As an example, a carrier may be a computer readable media as described above. In other examples a carrier may be a transmissible carrier such as an electronic or optical signal, which may be conveyed via electrical or optical cable or by radio or other means. It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application.

Claims

CLAIMS1 . A method performed by a controller in an inverter, the inverter being for converting a direct current, DC, into an alternating current, AC, to power an electric drive unit, EDU, in a vehicle, the method comprising: controlling the inverter to iteratively adjust an output current of the inverter, dependent on an input DC bus voltage applied to the inverter, to maintain voltage overshoots output by the inverter caused by a plurality of switching events in the inverter below a maximum operating voltage of the inverter.

2. A method as in claim 1 wherein the step of controlling the inverter to iteratively adjust the output current further comprises: maximising the output current of the inverter while maintaining the voltage overshoots below the maximum operating voltage of the inverter.

3. A method as in claim 1 or 2 wherein the step of controlling the inverter to iteratively adjust the output current comprises: increasing the output current in response to a drop in the DC bus voltage.

4. A method as in claim 3 comprising: increasing the output current according to a stepped profile dependent on a magnitude of the drop in the DC bus voltage.

5. A method as in claim 1 , 2 or 3 wherein the step of controlling the inverter to iteratively adjust the output current comprises: setting the output current to be inversely linearly proportional to the DV bus voltage.

6. A method as in claim 1 , 2 or 3 comprising: iteratively adjusting the output current according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained at the maximum operating voltage of the inverter.

7. A method as in claim 1 , 2, or 3 further comprising: iteratively adjusting the output current according to the DC bus voltage to cause one or more peaks of the voltage overshoots to be maintained above a threshold voltage, the threshold voltage being less than the maximum operating voltage of the inverter.

8. A method as in any one of the preceding claims further comprising: controlling the inverter to decrease the output current in response to an increase in the DC bus voltage.

9. A method as in any one of the preceding claims wherein the controller comprises a software module in the inverter and wherein the step of controlling the inverter to iteratively adjust the output current from the inverter comprises: receiving a measurement of the DC bus voltage; determining an output current level to be output by the inverter, dependent on the DC bus voltage; and sending an instruction to a power module to set the output current level of the inverter to the determined output current level.

10. A method as in any one of the preceding claims wherein a switching event comprises a switch in the inverter being switched from an on position to an off position; or from an off position to an on position.

11. An inverter for converting a direct current, DC, into an alternating current, AC, to power an Electric Vehicle, the inverter being configured to: iteratively adjust an output current of the inverter dependent on a DC bus voltage applied to the inverter, to maintain voltage overshoots caused by a plurality of switching events in the inverter below a maximum operating voltage of the inverter.

12. A control system for controlling an inverter of a vehicle, the control system comprising one or more processors collectively configured to: send an instruction to the inverter to operate according to the method of any one of claims 1 to 10.

13. A vehicle comprising the inverter of claim 11 .

14. The vehicle of claim 13 further comprising the control system of claim 12.

15. Computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the method according to any one of claims 1 to 10.

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