Method and apparatus for determining load index of power converter

Abstract

The invention relates to a device and a method for determining a load index of a power converter as part of a charging device for electrically operating a vehicle, having a power converter with a power electronic switching device and a control device for the power electronic switching device, a recording device stores a plurality of (i.e., at least three, in particular at least five) characteristics of the charging device, in particular the power converter, the charging device having an evaluation device which evaluates the plurality of characteristics and determines the load index from the plurality of characteristics, and when a first threshold value of the load index is reached, the recording device records the charging device, in particular the power converter. The evaluation device sends this information about the load index to a first superordinate decision device.

Description

Technical Field

[0001] The invention describes a method for determining a load index of a power converter as part of a charging device for electrically operated vehicles. The invention also describes a device for carrying out the method, wherein the recording device has a data storage device and wherein the evaluation device has a computing device. Background Art

[0002] DE 198 24 064 A1 discloses a circuit arrangement with detection of all instantaneous operating conditions as parameters, which generates an adaptive power cut-off threshold value from these permanently available values, which operates independently of the higher-level control system, so that a dynamic real-time evaluation of the performance characteristic map occurs, and thus currently normalized data about utilization and load factor are exclusively delivered to the higher-level control system of the controller in the form of a map-oriented overload evaluation. Thus, in the case of online temperature detection, the power section of each circuit arrangement can be fully protected from thermal overload. In order to calculate the losses, a large number of computing operations are required, which cannot be economically implemented using analog circuits. Low-cost microcontrollers can successfully be used as a solution for the inventive concept here. Digital data exchange with the controller is possible, and as a result, detailed error messages with digital actual value output are possible instead of cumulative error specifications.

[0003] EP 3 959 100 B1 discloses a method comprising: obtaining historical information of a charging station for an electric vehicle; computer-assisted calculation of a first reliability indicator based on the historical information, wherein the first reliability indicator corresponds to the reliability of the charging station for the electric vehicle during a first time period; computer-assisted calculation of a second reliability indicator based on the historical information, wherein the second reliability indicator corresponds to the reliability of the charging station during a second time period; computer-assisted calculation of a third reliability indicator based on the first reliability indicator and the second reliability indicator; and providing the third reliability indicator to a user; wherein calculating the first / second reliability indicator based on the historical information comprises: assigning points to at least one reliability indicator based on the historical information; and calculating the first / second reliability indicator based on the assigned points; wherein the at least one reliability indicator comprises at least the number of charging performed. Summary of the invention

[0004] Knowing the above-mentioned prior art, the present invention is based on the object of providing an improved and extended method and associated device for determining a load index of a power converter.

[0005] According to the invention, this object is achieved by a method for determining a load index of a power converter as part of a charging device for electrically operated vehicles, the charging device having a power converter with a power electronic switching device and a control device for the power electronic switching device, wherein a recording device stores a plurality of (that is to say at least three, in particular at least five) characteristics of the charging device, in particular the power converter, and the charging device has an evaluation device, which evaluates the plurality of characteristics and determines the load index from the plurality of characteristics and sends this information about the load index to a first superior decision-making device when a first threshold value for the load index is reached.

[0006] Preferably, the properties are selected in particular from the following properties: Time curve of the voltage at the input 20 of the power converter 2 Time curve of the current at the input 20 of the power converter 2 Electrical system utilization Number of charging processes Duration of each charging process Time curve of charging current corresponding to the charging process Time curve of charging voltage corresponding to the charging process Overvoltage in power electronic circuits Temperature of power converter components Dynamic pressure of cooling equipment Temperature at the output of the cooling device The speed of the fans that cool the equipment Ambient temperature Environmental relative humidity · Ambient particulate matter concentration.

[0007] It may be advantageous if, when a second threshold value for the load index is reached, this information is sent to a second superior decision device.

[0008] Furthermore, it may be advantageous if the data of the recording device are transmitted in full or in a selected manner to a third, superordinate decision-making device.

[0009] It may also be advantageous if the respective evaluation of the evaluation device is transmitted in full or in a selected form to a fourth superordinate decision device.

[0010] Each of these evaluation devices may be located at a different position. It may also be preferred that at least two of these evaluation devices coincide, that is to say are located at the same position and preferably are even identical.

[0011] It is preferred if the evaluation device determines the characteristics for the respective values ​​of the load index in a weighted manner, in particular in each case differently. For this purpose, from N characteristics, an M-tuple can be determined as the value of the load index, where M is less than or equal to N. Furthermore, individual characteristics can flow into one or more components of the M-tuple multiple times, and preferably in a differently weighted manner.

[0012] It may be particularly preferred if the weighting of the respective characteristics is parameterized externally during operation. Alternatively or additionally, it may be preferred if the weighting of the respective characteristics is parameterized by the evaluation device itself during operation.

[0013] It may also be advantageous if the evaluation device determines the load index from additional data of the other power converters. To this end, the decision device may provide the evaluation device with data of the other power converters.

[0014] In particular, it may be advantageous if data of other power converters flow into the parameterization.

[0015] Basically, it is preferred if the decision making device is reactive to the activation device and thereby changes the activation behavior of the power converter.

[0016] The object is also achieved by a device for carrying out the aforementioned method, which device has a power converter as part of a charging device for an electrically operated vehicle, wherein the power converter has a power electronic switching device and a control device for the power electronic switching device, wherein the recording device has a data storage device, wherein the evaluation device has a computing device, and wherein the superior decision-making device has a data transmission device.

[0017] It is advantageous if the charging device has a decision-making device.

[0018] It is preferred if the decision device is not designed as a part of the charging device, but is connected to the charging device via a data connection, preferably via a cloud connection.

[0019] It should be understood that the various embodiments of the present invention can be implemented individually or in any desired combination to achieve improvements. In particular, the features mentioned and explained above and below can be used not only in the specified combination, but also in other combinations or alone, without departing from the scope of the present invention and regardless of whether these features are disclosed in the context of a method or device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further explanations, advantageous details and features of the invention are to be found in the following description of exemplary embodiments of the invention, which are described in Figures 1 to 3Schematically shown in the figure, or schematically shown in its corresponding part.

[0021] Figure 1 A first embodiment of the device according to the invention is shown.

[0022] Figure 2 A second exemplary embodiment of the device according to the invention is shown, together with further components which are connected to it in terms of process engineering in the context of the method according to the invention.

[0023] Figure 3 Core aspects of the method according to the invention are shown. DETAILED DESCRIPTION

[0024] Figure 1 A first embodiment of a device according to the invention is shown. A power converter 2 is shown as part of a charging device 1 for an electrically operated vehicle, in particular a road vehicle. The power converter 2 is designed here in a simplified manner as a power electronic switching device 3 with a rectifier, which is supplied with power from an AC voltage supply system at its input 20 only as an example and outputs direct current at its output 22. Here, the rectifier can in particular have components for galvanic isolation and for increasing the voltage at its output 22.

[0025] The power converter 2 has a plurality of sensor devices 10 which, by way of example, sense the temperature of components of the power converter 2, more precisely the temperature of its power electronic switching devices 3. Furthermore, the power converter 2, more precisely its control device, has a sensor device 10 for determining the charging current. From sensor data of this type stored in a recording device 5 of the control device 4 and activation data for activating the power electronic switching devices 3, the activation device 6 of the control device 4 determines various characteristics, such as the number of charging processes, the duration of the individual charging processes, the time curve of the charging current of the respective charging processes, overvoltages within the power electronic circuit 3 and the temperature of components of the power converter 2.

[0026] These characteristics are processed in the evaluation device 6 to form a load index. Here, in particular other characteristics of the environment of the charging device, such as the ambient temperature and the particle concentration, also flow in. These two parameters are particularly important for determining the cooling performance of the cooling device for cooling the power converter. When a first threshold value for the load index is reached, this information is sent to a first superior decision device 7, which is here an integral component of the charging device 1. The decision device 7 determines a reaction from this information, which reaction can be designed by way of example as a reduction in the charging power or as a requirement for maintenance.

[0027] Figure 2A second embodiment of the device according to the invention and further components connected to the device in terms of process engineering in the context of the method according to the invention are shown. The power converter 2 is again shown as part of a charging device 1 for electrically operated vehicles, wherein the actual embodiment of the power electronic switching device is essentially irrelevant.

[0028] The recording device 5 is important, which stores a plurality of characteristics which are based on sensor evaluations and evaluations of the operating state of the power converter 2 .

[0029] Also refer to Figure 3 The evaluation device determines the corresponding value of the load index based on these characteristics. In essence, all characteristics can be weighted differently. In addition, individual characteristics can be included in the weighting multiple times, that is to say parameterized.

[0030] Furthermore, a data connection is shown, in particular a cloud connection to a decision device 7 which is not an integral component of the charging device 1. By way of example, the decision device 1 can be located at the manufacturer of the charging device, at the operator of the charging device or at the manufacturer of the power converter or in each case operated thereby.

[0031] The weighting of the respective characteristics can be parameterized during operation. Here, it is advantageous if the weighted parameters are sent from the decision device 7 to the evaluation device 6 or more generally to the control device 4. However, a change of the weighted parameters can also take place particularly effectively and quickly by the evaluation device 7 or the control device 4 itself. For this purpose, the evaluation device 7 or the control device 4 has a corresponding algorithm implemented at the evaluation device or the control device.

[0032] Furthermore, it is particularly effective if the weighted parameters by means of the evaluation device 7 are not only adapted based on the data of the charging device, but also additionally take into account parameters for determining the load index from additional data of other power converters and therefore also other charging devices 100. For this purpose, the decision device 7 can provide the evaluation device 6 with data of other power converters and therefore also other charging devices 100.

[0033] An important advantage is the direct or indirect reaction of the decision device 7 to the activation device 8 of the power converter 2. As a result, by way of example, the activation behavior of the power converter 2 can be changed compared to the basic setting during operation, as a result of which, for example, functional limitations of other power converters in other charging devices 100 can be reacted to in advance by certain characteristics, so that a fault at the power converter 2 does not occur or occurs in a delayed manner.

[0034] Figure 3The core aspects of the method according to the invention are shown. The plurality of sensors 10 arranged in the power converter 2 are shown only by way of example, wherein the sensor 12 is arranged in the charging device 1, outside the power converter 2 (see Figure 2 ), and a further sensor 112 is arranged in a further charging device 100. These sensors deliver properties to a recording device 5 (not explicitly shown).

[0035] The characteristics stored in the recording device are processed in the evaluation device 6. For this purpose, the various characteristics are evaluated individually and stored in a specified component of a 5-tuple, which is exemplary here. Some of these characteristics are stored together with other characteristics in a specified component of the 5-tuple. This 5-tuple (61, 62, 63, 64, 65) forms the value of the load index of the power converter 2 of the charging device 1.

[0036] As soon as a component or a selection of components exceeds the set first threshold, this excess is transmitted to the superior decision-making device 7 .

[0037] On the basis of this transmission, in particular including the load index of the further charging device 1 , the decision device 7 initiates a change in the weighting of one or more characteristics via the data transmission device, if necessary.

[0038] The weighting of the characteristics can thus be parameterized, that is to say varied, during operation, that is to say over the entire service life of the charging device 1. Thus, the power converter, in particular its output power, can always be adjusted and only temporarily adjusted when necessary, for example when the power supply system is overloaded.

[0039] Alternatively or additionally, maintenance or even replacement of the power converter 2 or the charging device 1 can generally be carried out based on the aforementioned transmission.

[0040] The decision device therefore has a learning algorithm which performs a parameterization of the weighting of the characteristics of the charging device 1 and the power converter 2 externally and alternatively or additionally also independently.

Claims

1. A method for determining a load index of a power converter (2) as part of a charging device (1) for electrically operated vehicles, the charging device (1) having a power converter (2), the power converter (2) having a power electronic switching device (3) and a control device (4) for the power electronic switching device, wherein: The recording device (5) stores a plurality of characteristics of the charging device (1), in particular the power converter (2), and the charging device (2) has an evaluation device (6) which evaluates the plurality of characteristics and determines the load index from the plurality of characteristics and sends this information about the load index to a first superior decision device (7) when a first threshold value of the load index is reached.

2. The method of claim 1, wherein The characteristics are specifically selected from the following characteristics: The time curve of the voltage at the input terminal 20 of the power converter 2 The time curve of the current at the input terminal 20 of the power converter 2 Electrical system utilization Number of charging processes Duration of each charging process Time curve of charging current corresponding to the charging process Time curve of charging voltage corresponding to the charging process Overvoltage in power electronic circuits · Temperature of components of the power converter Dynamic pressure of cooling equipment The temperature at the output of the cooling device The speed of the cooling device's fan Ambient temperature Environmental relative humidity · Ambient particulate matter concentration.

3. The method according to claim 1 or 2, wherein: When a second threshold value of the load index is reached, this information is sent to a second superior decision-making device.

4. The method according to claim 1 or 2, wherein: The data of the recording device (5) is sent to the third superior decision-making device in a complete or selected manner.

5. The method according to claim 1 or 2, wherein: The corresponding evaluation of the evaluation device (6) is sent in full or in a selected manner to a fourth superior decision-making device.

6. The method according to claim 1 or 2, wherein: The evaluation device (6) determines the characteristic in a weighted manner for the respective value of the load index, in particular determines the characteristic differently in each case.

7. The method of claim 6, wherein: From the N characteristics, M tuples (61, 62, . . . , 6M) can be determined as the value of the load index, where M is less than or equal to N.

8. The method of claim 7, wherein: Individual characteristics can flow multiple times and preferably in a differently weighted manner into one or more components of the M-tuple ( 61 , 62 , . . . , 6M).

9. The method according to claim 6, wherein: The respective weighting of the characteristics during operation is parameterized externally.

10. The method according to claim 6, wherein: The respective weighting of the characteristics during operation is parameterized by the evaluation device (7) itself.

11. The method according to claim 1 or 2, wherein: The evaluation device (7) determines the load index from additional data of other power converters or other charging devices (100).

12. The method of claim 11, wherein: The decision device (7) provides data of other power converters or other charging devices (100) to the evaluation device (6).

13. The method according to claim 6, wherein: Data of other power converters or other charging devices (100) flow into the parameterization.

14. The method according to claim 1 or 2, wherein: The decision device is responsive to an activation device (8) and thereby changes the activation behavior of the power converter.

15. A device for carrying out the method according to any of the preceding claims, the device having a power converter (2) as part of a charging device (1) for an electrically operated vehicle, wherein the power converter (2) has a power electronic switching device (3) and a control device (4) for the power electronic switching device, wherein the recording device (5) has a data storage device, wherein the evaluation device (6) has a computing device, and wherein the superior decision-making device (7) has a data transmission device.

16. The device according to claim 15, wherein: The charging device (1) has the decision device (7).

17. The apparatus according to claim 15, wherein: The decision device (7) is not designed as a part of the charging device (1), but is connected to the charging device (1) via a data connection, preferably a cloud connection.

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