Method for forming an electrolytic capacitor of a vehicle device, method for operating a vehicle device, electronic vehicle device and vehicle

Abstract

The invention relates to a method for forming an electrolytic capacitor (5) of a vehicle device (1), comprising the following steps: - applying an electrical voltage, which has an initial voltage value (13), to the electrolytic capacitor (5) that is to be formed using an energy management element (4) of the vehicle device (1); - increasing the electrical voltage from the initial voltage value (13) to a target voltage value (14) during a predefined time interval (15) of the formation using the energy management element (4); and - ending the formation when the time interval (15) has elapsed.

Description

[0001] Method for forming an electrolytic capacitor of a vehicle device, method for operating a vehicle device, electronic vehicle device and vehicle

[0002] Aspects of the invention relate to a method for forming an electrolytic capacitor of a vehicle device, a method for operating a vehicle device, an electronic vehicle device and a vehicle.

[0003] Vehicle components, such as vehicle sensors, use electrolytic capacitors to stabilize power supplies. Electrolytic capacitors have an oxide layer as their dielectric, which degrades when the capacitor is de-energized for extended periods. Methods for re-forming, i.e., healing, the oxide layer are known, for example, from DE 10 2008 060 546 B3.

[0004] A disadvantage of the known methods is that the electrolytic capacitor must be connected to an external device for forming.

[0005] The object of the invention is to provide a method for forming an electrolytic capacitor of a vehicle device, a method for operating the vehicle device, a vehicle device and a vehicle in order to improve the forming of the electrolytic capacitor.

[0006] One aspect of the invention relates to a method for forming an electrolytic capacitor for a vehicle device. The method comprises, in particular, the following steps:

[0007] In particular, applying an electrical voltage to the electrolytic capacitor to be formed by means of an energy management element of the vehicle unit, especially such that, in particular, the voltage provided for forming is controlled internally by the vehicle unit. The electrical voltage has an initial voltage value.

[0008] In particular, increasing the electrical voltage from the initial voltage value to a target voltage value during a predetermined time interval of the formation process with the energy management element, especially such that an internal vehicle device voltage change is carried out with the energy management element to adjust the voltage for formation; and

[0009] In particular, stopping the forming process when the time interval has expired.

[0010] This method makes it possible to form an electrolytic capacitor without an external device within the vehicle's electrical system and, in particular, without any manual intervention. This saves time and money. By increasing the voltage, which can also be referred to as the forming voltage, over a predetermined time interval, any voltage-dependent residual current, especially within the vehicle's electrical system, is limited, thus reducing the risk of the electrolytic capacitor being damaged by this residual current. Such a voltage control method for forming, implemented within the vehicle's electrical system, also enables very precise forming and a procedure more tailored to the specific electrolytic capacitor.

[0011] The power management element is specifically an integrated circuit (PMIC) for providing and monitoring the voltages of the vehicle's electrical system. The PMIC is designed to establish a power sequencing sequence for other components of the vehicle's electrical system and to initiate that sequence. The power management element includes, for example, a voltage regulator unit. This voltage regulator unit is specifically configured to regulate and provide a voltage to the value set at the output of the power management element. The voltage regulator unit is, for example, a low dropout regulator (LDO). The use of such an integrated PMIC significantly enhances the advantages mentioned above.

[0012] For example, the vehicle device has a processing unit, which can also be called an evaluation unit. In particular, the processing unit controls the voltage regulator unit. It is possible that the power management element includes the processing unit. It is also possible that the processing unit, or at least part of it, is a microcontroller of the vehicle device. For example, the microcontroller can transmit the forming voltage to be set to the power management element via a communication interface. Preferably, the microcontroller's power supply is independent of the forming voltage to be set. This design allows the method to be carried out without requiring the vehicle device to be installed in a vehicle. In particular, providing and connecting it to a power source is sufficient.

[0013] In particular, this is a process for reforming the electrolytic capacitor. Specifically, an existing oxide layer on the capacitor is cured and, in particular, not fundamentally created for the first time, as is the case with a manufacturing process.

[0014] The initial and target voltage values ​​are set by the PMIC. A voltage of the respective value is applied to the output of the PMIC. For example, the initial and target voltage values ​​are stored in a memory of the PMIC. The target voltage value preferably corresponds to the nominal voltage of the electrolytic capacitor.

[0015] The vehicle device is, in particular, a vehicle sensor or a vehicle control unit. It is therefore a single unit to be considered as a whole, for example, in a common housing. The unit is, in particular, a locally common assembly, especially arranged on a single printed circuit board. For example, the vehicle device is a low-voltage device with a maximum operating voltage of less than 100 volts, in particular less than 48 volts, and in particular less than 24 volts. In particular, the vehicle device does not have a pre-charging circuit.

[0016] The electrolytic capacitor comprises, in particular, a liquid electrolyte. The anode material is preferably aluminum. The method can also be carried out for other electrolytic capacitors, such as tantalum capacitors. In particular, the electrolytic capacitor is arranged in the vehicle device for voltage buffering for a downstream circuit, for example, a system-on-a-chip (SoC).

[0017] In one embodiment, the voltage at the output of the power management element is increased stepwise in discrete stages. This embodiment is particularly simple and can be implemented without additional components. Preferably, the PMIC is configured to set different voltages at its output. For example, the PMIC first sets the initial voltage and, after a predetermined interval, a first intermediate voltage. The intermediate voltage is preferably higher than the initial voltage. After another predetermined interval, the PMIC sets, for example, the target voltage at its output. It is also possible for the PMIC to set further intermediate voltages after further intervals before setting the target voltage. For example, the time interval corresponds to the sum of the intervals.It is possible for the intermediate time intervals to be of equal length. However, it is also possible for the intermediate time intervals to be of different lengths. The length of the intermediate time intervals is stored in the PMIC's memory.

[0018] For example, the residual current increases sharply with each increase in the voltage at the PMIC's output and then decreases again over the intermediate interval. Specifically, the intermediate intervals and intermediate voltages are stored in the PMIC's memory in such a way that the residual current does not exceed a maximum value. This reduces the risk of component damage due to excessive residual current.

[0019] In an alternative embodiment, the voltage at the output of the power management element is increased continuously, for example linearly. A specific voltage curve is predefined in the PMIC's memory. This embodiment further reduces residual current peaks.

[0020] In one embodiment, a current draw limit is provided. The current draw of the electrolytic capacitor is measured at least once during the formation process, within the time interval used to check the formation state. The measured current draw is provided to the power management element. A voltage rise curve at the output of the power management element is adjusted depending on the provided current draw, particularly if it exceeds the provided current draw limit. The measurement is performed, in particular, by the PMIC, especially automatically. For example, several different voltage curves are provided. Depending on the measured current draw, one of the several curves is selected. The several curves differ, for example, with respect to the intermediate voltage values ​​and / or the intermediate intervals.

[0021] For example, the current draw is proportional to the residual current. The residual current may serve as an indicator of the electrolytic capacitor's formation state. For instance, the current draw is measured after setting the initial voltage. Preferably, depending on the measured current draw, one of several curves is selected, and the voltage is adjusted accordingly. If the current draw is high, a curve with a longer time interval may be selected.

[0022] It is also possible that after each intermediate voltage value is set, the current draw is measured and provided. Depending on the current draw, the next intermediate voltage value and / or the next intermediate interval may be changed.

[0023] This embodiment allows for a forming process that is tailored to the electrolytic capacitor's state of formation. This reduces the risk of electrolytic capacitor damage due to high residual current and can potentially make the forming process more efficient.

[0024] In one embodiment, a storage time is provided. The storage time indicates how long the vehicle device was not connected to a power supply. Depending on the storage time, a voltage ramp-up curve is adjusted before the voltage is applied to the electrolytic capacitor. In this embodiment as well, it is possible to select from several available ramp-ups.

[0025] For example, the desired curve can be selected even before setting the initial voltage value. If necessary, the selection can be corrected or adjusted after measuring the current draw.

[0026] In one embodiment, the curve is adjusted such that the initial stress value is lower for longer storage times than for shorter storage times. Specifically, the initial stress value is set higher for shorter storage times than for longer storage times. This allows the forming process to be adapted to the specific situation.

[0027] In one embodiment, a quality parameter for the electrolytic capacitor is provided. The voltage increase curve is adjusted according to this quality parameter before the voltage is applied to the electrolytic capacitor. In particular, the specified time interval is adjusted according to the provided quality parameter.

[0028] For example, the quality parameter depends on a capacitance, particularly the nominal capacitance of the electrolytic capacitor. It is also possible that the quality parameter depends on the current temperature and / or humidity, and / or the temperature and / or humidity during storage and / or manufacturing of the electrolytic capacitor. For instance, the quality parameter depends on the capacitor's history, such as a soldering process in which the electrolytic capacitor is soldered onto a circuit board of the vehicle device.

[0029] In particular, the quality parameter is determined by the PMIC. If necessary, it reads temperature or humidity sensors from the vehicle's device, especially automatically.

[0030] For example, the curve is selected depending on the provided quality parameter. If necessary, the lower the quality parameter, the lower the initial voltage value and / or the longer the time interval. A low quality parameter may also indicate conditions that promote a high residual current, such as high temperature or humidity.

[0031] In one embodiment, the provided quality parameter characterizes an anode material and / or an electrolyte of the electrolytic capacitor. For example, the quality parameter depends on the chemical compatibility of the electrolyte with the oxide layer. In particular, the quality parameter depends on the water content of the electrolyte. The higher the water content of the electrolyte, the lower the quality parameter. It is possible that a look-up table (LuT) is provided, for example, in the memory of the PMIC. For example, different curves are assigned to different quality parameters in the LuT. Depending on the quality parameter, one of the curves is selected.

[0032] Another aspect of the invention relates to a method for operating a vehicle device. The vehicle device comprises an electrolytic capacitor and a power management element. The method comprises the following steps: Information is determined indicating whether electrolytic capacitor formation is required. A method for forming the electrolytic capacitor is then carried out according to the aforementioned aspect of the invention or an embodiment thereof, if the information indicates that electrolytic capacitor formation is required.

[0033] In one embodiment, an operating voltage is generated at the output of the power management element to operate the vehicle device. If, for example, the information indicates that a formation is required, the operating voltage is set after the formation. If, for example, the information indicates that no formation is required, the operating voltage is set without formation, and in particular immediately. This allows the vehicle device to be switched on without unnecessary delay.

[0034] In one embodiment, the following steps are performed to determine the information. For example, a residual voltage across a capacitor in the vehicle's control unit is measured to estimate storage time and, in particular, provided to the PMIC (Power Management Interface). The measurement is performed, in particular, by the PMIC, preferably automatically. A voltage threshold is provided. If the measured residual voltage falls below the voltage threshold, the information is determined to indicate that the electrolytic capacitor needs to be reformed. The electrolytic capacitor that may need to be reformed is different from the capacitor. The capacitor is, for example, a ceramic capacitor or a so-called GoldCap capacitor. In particular, the capacitor fulfills an additional function as a component of the vehicle's control unit, so that the control unit does not have an unnecessary additional component.

[0035] For example, if the vehicle unit is disconnected from its power supply, either by unplugging it or by having its power supply battery discharge, the capacitor will discharge over time. Therefore, the capacitor's residual voltage indicates the time elapsed since the vehicle unit was disconnected from its power supply. This time may correspond to the storage period. During storage, a vehicle containing the unit may be taken out of service, the unit may be removed from the vehicle, or it may not have been installed at all and is being stored.

[0036] In one embodiment, the voltage rise curve across the electrolytic capacitor is adjusted depending on the measured residual voltage. Specifically, one of several possible curves is selected based on the measured residual voltage. The lower the residual voltage, the longer the storage time.

[0037] In one embodiment, the following steps are performed to determine the information. A storage time of the vehicle device since it was disconnected from a power source is provided. A maximum time period is provided. Specifically, the vehicle device is connected to the power source. If the storage time exceeds the maximum time, the information is determined that the electrolytic capacitor needs to be reformed.

[0038] In one embodiment, the voltage source is connected to the vehicle device after the maximum time period has elapsed or as soon as the residual voltage falls below the limit voltage value, particularly automatically. This reduces storage damage and allows stored vehicle devices to be quickly available when needed.

[0039] In one embodiment, after reaching the target voltage, the energy management element first sets the voltage at its output to a lower voltage value, for example, 0 volts. Subsequently, the energy management element sets the voltage at its output to an operating voltage, regardless of the predefined time interval. The operating voltage may correspond to the nominal voltage of the electrolytic capacitor.

[0040] Resetting the voltage to the lower voltage value after forming may also reset the downstream circuitry. This prevents malfunctions in the downstream circuitry caused by the slow voltage increase. In one embodiment, the energy management element sends information to a vehicle's processing unit indicating whether the process has been completed, and in particular, whether it was successful. This allows the processing unit to know whether the vehicle device is functioning. If the vehicle device is, for example, a vehicle sensor such as a parking sensor, then a parking assistance system is only available once the parking sensor's PMIC has sent a status signal to the processing unit indicating that it is ready for use.

[0041] Another aspect of the invention relates to an electronic vehicle device. The vehicle device is configured, for example, as a vehicle sensor or a vehicle control unit. The vehicle device comprises an electrolytic capacitor and a power management element. An output of the power management element is electrically connected to the electrolytic capacitor. The power management element is arranged and configured to set an electrical voltage at its output, which has an initial voltage value. The power management element is also arranged and configured to increase the electrical voltage from the initial voltage value to a target voltage value during a predetermined time interval of the formation process.

[0042] In one embodiment, the vehicle-mounted device is configured to execute a method according to the aspects mentioned above or an embodiment thereof. In particular, the vehicle-mounted device performs the method.

[0043] In one embodiment, the electronic vehicle device has an integrated chip (IC or SoC). The integrated chip is electrically connected to the electrolytic capacitor at its power supply input. The electrolytic capacitor serves, in particular, as a voltage buffer for the integrated chip.

[0044] Another aspect of the invention relates to a vehicle with a computing unit and an electronic vehicle device according to the above-mentioned aspect of the invention or an embodiment thereof.

[0045] The advantages and embodiments of the aspects of the invention are mutually transferable.

[0046] The following describes exemplary embodiments of the invention. Figure 1 shows an exemplary embodiment of an electronic vehicle control unit and a vehicle battery;

[0047] Fig. 2 shows two schematic examples of a voltage curve; and

[0048] Fig. 3 shows a flowchart of an exemplary embodiment of a method for operating a vehicle device.

[0049] In the figures, identical reference symbols denote functionally equivalent elements.

[0050] Fig. 1 schematically shows an embodiment of an electronic vehicle device 1 and a vehicle battery 2. The vehicle device 1 has, for example, a plug 3 with which the vehicle device 1 can be connected to the vehicle battery 2.

[0051] The vehicle device 1 is, for example, a vehicle sensor or a vehicle control unit. The vehicle device 1 comprises a power management element 4 and an electrolytic capacitor 5. For example, the vehicle device 1 comprises a system-on-a-chip (SoC) 6. Preferably, the power management element 4, the electrolytic capacitor 5, and the SoC 6 are arranged together on a printed circuit board.

[0052] For example, a positive voltage supply line of the connector is electrically connected to a voltage input 8 of the power management element 4. Optionally, a voltage output 9 of the power management element 4, which can also simply be referred to as an output, is electrically connected to a first terminal 10 of the electrolytic capacitor 5, for example via a conductor trace. A second terminal 11 of the electrolytic capacitor is, for example, electrically connected to a ground potential of the circuit board. For example, the voltage output 9 of the power management element 4 is electrically connected to a voltage input 12 of the single-chip system. In particular, the voltage output 9 of the power management element 4, the voltage input 12 of the single-chip system, and the first terminal 10 of the electrolytic capacitor 5 are at a common electrical potential.In particular, the vehicle device 1 is configured to perform a method for forming the electrolytic capacitor 5. For example, the power management element 4 generates an electrical voltage, particularly at its voltage output 9, which has an initial voltage value 13 (Fig. 2). The generated voltage is thus applied, in particular, to the first terminal 10. The power management element 4 increases the electrical voltage from the initial voltage value 13 to a target voltage value 14 (Fig. 2) during a predetermined time interval 15 (Fig. 2) of the forming process. In particular, the forming process is completed, especially by the power management element 4, when the time interval 15 has elapsed.

[0053] In one embodiment, the energy management element 4 comprises an evaluation unit 16 with a storage unit 17. In particular, the energy management element 4 is configured to carry out an embodiment of a method for operating the electrolytic capacitor 5 as illustrated by way of example in Fig. 3. Specifically, the energy management element 4 carries out the method. In particular, the method comprises step S1, step S2, and step S3.

[0054] In step S1, for example, information is provided, particularly to evaluation unit 16, regarding whether a formation is required. Evaluation unit 16 determines, for instance, whether a storage time exceeds a predefined maximum time. If this is the case, a formation is required, and step S2 is then executed.

[0055] To determine the storage time, for example, the evaluation unit 16 reads an unspecified time unit from the energy management element 4. For example, the energy management element 4 detects when plug 3 is no longer connected to the vehicle battery 2. The time unit then begins counting from this point.

[0056] If formation is required, it is carried out, for example, in step S2. For instance, the energy management element 4 sets the initial voltage value 13 depending on the storage time. If necessary, the energy management element 4 measures the current consumption of the electrolytic capacitor 5.

[0057] Optionally, the evaluation unit 16 determines an intermediate interval 18 and / or an intermediate voltage value 19 depending on the measured current consumption. In one embodiment, it is possible for the energy management element 4 to set a higher intermediate voltage value 19 at its voltage output 9 after each intermediate interval 18 has elapsed, in particular until the time interval 15 has expired.

[0058] In an alternative embodiment, the evaluation unit 16 determines, particularly depending on the storage time and / or a quality parameter and / or the measured current consumption, a profile from several predefined profiles 20, 21, as shown by way of example in Fig. 2. It is possible that the several profiles differ with respect to their intermediate intervals 18 and / or the initial voltage value 13 and / or the intermediate voltage values ​​19. A continuous profile 21 is also possible, if applicable. For example, the profiles are stored in the storage unit 17.

[0059] After the time interval 15 has elapsed, or if step S2 determines that no formation is required, step S3 is performed. In step S3, the power management element 4 provides an operating voltage with a specific operating voltage value for the single-chip system 6 at its voltage output 9.

[0060] In one embodiment, a reset of the single-chip system 6 is performed before the operating voltage is supplied. For example, the power management element 4 sets the voltage at its voltage output 9 to 0 volts and then to the operating voltage value. Preferably, the power management element 4 receives a status from the single-chip system 6 regarding its operational readiness. In particular, the power management element 4 sends the received status to an external control unit of the vehicle.

Claims

Patent claims 1. Method for forming an electrolytic capacitor (5) of a vehicle device (1), comprising the following steps: Applying an electrical voltage having an initial voltage value (13) to the electrolytic capacitor (5) to be formed with an energy management element (4) of the vehicle device (1); Increasing the electrical voltage from the initial voltage value (13) to a target voltage value (14) during a predetermined time interval (15) of the formation with the energy management element (4); and Forming stops when the time interval (15) has elapsed.

2. Method according to claim 1, wherein the voltage at the output of the energy management element (4) is gradually increased in discrete steps by the energy management element (4).

3. Method according to claim 1 or 2, wherein a current consumption limit is provided and a current consumption of the electrolytic capacitor (5) is measured at least once during the time interval (15) for checking the formation state during formation and is provided to the power management element (4) and a curve (20, 21) of the increase of the voltage at the output of the power management element (4) is adapted depending on the provided current consumption if it exceeds the provided current consumption limit.

4. Method according to one of the preceding claims, wherein a storage time is provided which indicates how long the vehicle device (1) was not connected to a power supply, wherein, depending on the storage time, a curve (20, 21) of the increase of the voltage before the voltage is applied to the electrolytic capacitor (5) is adapted.

5. Method according to claim 4, wherein the curve (20, 21) is adapted such that the initial stress value (13) is smaller for a longer storage time than for a shorter storage time.

6. Method according to one of the preceding claims, wherein a quality parameter of the electrolytic capacitor (5) is provided and a curve (20, 21) of the increase of the voltage is adapted depending on the provided quality parameter before the voltage is applied to the electrolytic capacitor (5), in particular the specified time period is adapted.

7. Method according to claim 6, wherein a quality parameter is provided which characterizes an anode material and / or an electrolyte of the electrolytic capacitor (5).

8. Method for operating a vehicle device (1) with an electrolytic capacitor (5) and a power management element (4), comprising the steps of: determining information indicating whether a forming of the electrolytic capacitor (5) is required; Performing a method for forming the electrolytic capacitor (5) according to any of the preceding claims, if the information includes that the forming of the electrolytic capacitor (5) is required.

9. Method according to claim 8, wherein an operating voltage is generated at the output of the energy management element (4) to operate the vehicle device (1).

10. The method of claim 8 or 9, wherein the following steps are performed to determine the information: Measuring a residual voltage across a capacitor of the vehicle device (1); providing a voltage limit value; Determine as information that the forming of the electrolytic capacitor (5) is required if the measured residual voltage falls below the voltage limit, wherein the capacitor to be formed is different from the capacitor.

11. Method according to claim 10, wherein a curve (20, 21) of the increase of the voltage at the electrolytic capacitor (5) is adapted depending on the measured residual voltage.

12. The method of claim 8 or 9, wherein the following steps are performed to determine the information: Providing a storage time for the vehicle device (1) since the vehicle device (1) has not been connected to a power source; Providing a maximum time span; Determine as information that the electrolytic capacitor (5) needs to be reformed if the storage time exceeds the maximum time.

13. Method according to claim 12, wherein the voltage source is connected to the vehicle device (1) after the maximum time period has elapsed, in particular automatically.

14. Method according to any one of claims 8 to 13, wherein the energy management element (4), after reaching the target voltage, first sets the voltage at its output to a lower voltage value and then sets it to an operating voltage regardless of the specified time period.

15. Method according to any one of claims 8 to 14, wherein the energy management element (4) sends information to a computing unit of a vehicle as to whether the method has been terminated.

16. Electronic vehicle device (1) comprising an electrolytic capacitor (5) and a power management element (4), wherein an output of the power management element (4) is electrically connected to the electrolytic capacitor (5), wherein the power management element (4) is arranged and configured to set an electrical voltage at its output having an initial voltage value (13); and to increase the electrical voltage from the initial voltage value (13) to a target voltage value (14) during a predetermined time interval (15) of formation.

17. Electronic vehicle device (1) according to claim 16, wherein the electronic vehicle device (1) has an integrated chip, the integrated chip being electrically connected to the electrolytic capacitor (5) at a power supply input.

18. Vehicle with a computing unit and an electronic vehicle device (1 ) according to one of claims 16 or 17.

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