Method and device for determining a load index of a power converter

Abstract

A device and a method for determining a load index of a power converter as part of a charging device for electrically powered vehicles are presented, comprising a power converter which has a power electronic switching device and a control device for this purpose, wherein a protocol device stores a plurality, i.e. at least three, in particular at least five, of characteristic values ​​of the charging device and in particular of the power converter, with an evaluation device which evaluates the plurality of characteristic values ​​and determines the load index from this and transmits this information to a first higher-level decision-making device when a first threshold value of the load index is reached.

Description

[0001] The invention describes a method for determining a load index of a power converter as part of a charging device for electrically powered vehicles. The invention further describes a device for implementing this method, comprising a logging device, a data storage device, and an evaluation device, a computing device.

[0002] DE 198 24 064 A1 discloses a circuit arrangement with a recording of all current operating conditions as parameters, which generates a self-adapting current cutoff threshold from these permanently present values. This threshold operates independently of the higher-level control system, enabling a dynamic real-time evaluation of the power parameter map. Thus, only currently standardized data on the utilization and load capacity are delivered to the controller's higher-level control system in the form of a map-oriented overload evaluation. With online temperature recording, the power section of any circuit arrangement can be completely protected against thermal overload. Calculating the losses requires extensive computational operations that cannot be economically implemented with analog circuits. A low-cost microcontroller can be successfully used as a solution for the inventive idea.Digital data exchange with a controller is possible, allowing detailed error messages instead of summary error naming with a digital actual value output.

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

[0004] In view of the above-mentioned prior art, the object of the invention is to provide an improved and expanded method and an associated device for determining a load index of a power converter.

[0005] This object is achieved according to the invention by a method for determining a load index of a power converter as part of a charging device for electrically operated vehicles, with a power converter which has a power electronic switching device and a control device therefor, wherein a protocol device stores a plurality, i.e. at least three, in particular at least five, of characteristic variables of the charging device and in particular of the power converter, with an evaluation device which evaluates the plurality of characteristic variables and determines the load index therefrom and, when a first threshold value of the load index is reached, transmits this information to a first higher-level decision device.

[0006] It is preferred if the parameters are selected in particular from: • Time course of the voltage at input 20 of the power converter 2 • Time course of the current at input 20 of the power converter 2 • Network utilization • Number of charging processes • Duration of each charging process • Time course of the charging current of the respective charging process • temporal progression of the charging voltage of the respective charging process • Overvoltages within the power electronic circuit • Temperature of converter components • Back pressure of a cooling device • Temperature at the outlet of the cooling device • Speed ​​of a cooling fan • Ambient temperature • Relative humidity of the environment • Fine dust concentration in the environment.

[0007] It may be advantageous if, when a second threshold value of the load index is reached, this information is transmitted to a second higher-level decision-making device.

[0008] It may also be advantageous if the data from the protocol device is transmitted in full or in selected form to a third, higher-level decision-making device.

[0009] It may also be advantageous if the respective assessments of the evaluation facility are transmitted in full or in a selected manner to a fourth higher-level decision-making facility.

[0010] Each of these evaluation devices can be located at a different location. It may also be preferable for at least two of these evaluation devices to coincide, i.e., be located at the same location and, preferably, even be identical.

[0011] It is preferred if the evaluation device determines the parameters, in particular each with different weightings, for a respective value of the load index. For this purpose, an M-tuple can be determined from N parameters as the value of the load index, where M is less than or equal to N. Furthermore, individual parameters can be incorporated into one or more components of the M-tuple multiple times, preferably with different weightings.

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

[0013] It may be advantageous for the evaluation unit to determine the load index from additional data from other power converters. For this purpose, the decision unit can make the data from other power converters available to the evaluation unit.

[0014] In particular, it can be advantageous if the data from other power converters are included in the parameterization.

[0015] In principle, it is preferred if the decision device acts back on a control device and thereby changes its control method of the power converter.

[0016] The object is further achieved by a device for carrying out the said method, comprising a power converter as part of a charging device for electrically operated vehicles, wherein the power converter has a power electronic switching device and a control device therefor, wherein a protocol device has a data storage device, wherein an evaluation device has a computing device and wherein a higher-level decision device has a data transmission device.

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

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

[0019] It is understood that the various embodiments of the invention can be implemented individually or in any combination to achieve improvements. In particular, the features mentioned and explained above and below can be used not only in the specified combinations, but also in other combinations or on their own, without departing from the scope of the present invention and regardless of whether they are disclosed within the scope of the method or device.

[0020] Further explanations of the invention, advantageous details and features, emerge from the following description of the Fig. 1 to 3 schematically illustrated embodiments of the invention, or of respective parts thereof. Fig. 1 shows a first embodiment of a device according to the invention. Fig. 2 shows a second embodiment of a device according to the invention and further components connected to it in the context of the method according to the invention. Fig. 3 shows a core aspect of the method according to the invention.

[0021] Fig. Figure 1 shows a first embodiment of a device according to the invention. It depicts a power converter 2 as part of a charging device 1 for electrically powered vehicles, in particular road vehicles. The power converter 2 is simplified here as a power electronic switching device 3 with a rectifier, which, purely by way of example, is fed with power from an AC voltage supply network at its input 20 and outputs a direct current at its output 22. In this case, the rectifier can, in particular, have components for galvanic isolation and for increasing the voltage at its output 22.

[0022] The power converter 2 has a plurality of sensor devices 10, which, for example, measure the temperature of components of the power converter 2, more precisely its power electronic switching device 3. Furthermore, the power converter 2, or more precisely its control device, has a sensor device 10 for determining the charging current. From such sensor data, which are stored in a protocol device 5 of the control device 4, and the control data for controlling the power electronic switching device 3, the evaluation device 6 of the control device 4 determines various parameters, such as the number of charging processes, the duration of the individual charging process, the temporal profile of the charging current of the respective charging process, overvoltages within the power electronic circuit 3, and the temperature of components of the power converter 2.

[0023] These parameters are processed into a pollution index in the evaluation device 6. This includes additional parameters, particularly those relating to the environment of the charging device, such as ambient temperature and particulate matter concentration.

[0024] These two parameters are particularly important for determining the cooling capacity of a cooling device for cooling the power converter. When a first threshold value of the load index is reached, this information is transmitted to a first higher-level decision device 7, which in this case is an integral part of the charging device 1. The decision device 7 uses this information to determine a response, which can be implemented, for example, as a reduction in the charging power or as a maintenance request.

[0025] Fig. Figure 2 shows a second embodiment of a device according to the invention and further components technically connected to it within the scope of the method according to the invention. It again shows a power converter 2 as part of a charging device 1 for electrically powered vehicles, whereby the specific design of the power electronic switching device is fundamentally irrelevant.

[0026] The protocol device 5 is essential, which stores a plurality of parameters based on sensor evaluations and on evaluations of the operating states of the power converter 2.

[0027] The evaluation device determines, see also Fig. 3, a respective value of the stress index from these parameters. In principle, all parameters can be weighted differently. Individual parameters can also be included in the weighting multiple times, thus being parameterized.

[0028] Also shown is a data connection, in particular a cloud connection, to a decision-making device 7, which is not an integral part of the charging device 1. For example, the decision-making device 1 can be located at the manufacturer of the charging device, the operator of the charging device, or the manufacturer of the power converter, or can be operated by them.

[0029] The weighting of the respective parameters can be parameterized during operation. It is advantageous if the weighting parameters are transmitted from the decision device 7 to the evaluation device 6 or, more generally, to the control device 4. However, the weighting parameters can also be changed particularly efficiently 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 therein.

[0030] Furthermore, it is particularly efficient if the weighting parameters of the evaluation device 7 are not only adjusted based on data from the charging device, but additional parameters for determining the load index are also drawn from additional data from other power converters and thus from other charging devices 100. For this purpose, the decision device 7 can make the data from other power converters and thus from other charging devices 100 available to the evaluation device 6.

[0031] A significant advantage arises from the fact that the decision device 7 directly or indirectly reacts to a control device 8 of the power converter 2. This allows, for example, the control method of the power converter 2 to be changed compared to a basic setting during operation, whereby, for example, functional limitations of other power converters in further charging devices 100 can be reacted to so early by certain parameters that the fault in the power converter 2 itself does not occur or occurs with a delay.

[0032] Fig. Figure 3 shows a core aspect of the method according to the invention. Shown purely by way of example are a plurality of sensors 10 arranged in the power converter 2, a sensor 12 arranged in the charging device 1 outside the power converter 2 (cf. Fig.2) and a further sensor 112, which is arranged in another charging device 100. These sensors provide parameters to the protocol device 5, which is not explicitly shown.

[0033] The parameters stored in the protocol device are processed in the evaluation device 6. For this purpose, various parameters are evaluated individually and stored in an assigned component of a 5-tuple, shown here as an example. Some parameters are stored together with other parameters in assigned components of the 5-tuple. This 5-tuple 61, 62, 63, 64, 65 forms a value of the load index of power converter 2 of charging device 1.

[0034] As soon as a component or a selection of several components exceeds a predetermined first threshold value, this exceedance is transmitted to the higher-level decision device 7.

[0035] On the basis of this transmission and in particular taking into account load indices of further charging device 1, the decision device 7 initiates a change in the weightings of one or more parameters via a data transmission device if necessary.

[0036] This allows the weighting of the parameters to be parameterized, i.e., changed, during ongoing operation—that is, throughout the entire service life of the charging device 1. This allows the power converter, particularly its output power, to be adjusted at any time and only temporarily, as needed, for example, in the event of an overload of the supplying power grid.

[0037] Alternatively or additionally, maintenance or even replacement of the power converter 2 or the charging device 1 in general can be initiated on the basis of the aforementioned transmission.

[0038] The decision-making device thus has a learning algorithm which externally and, alternatively or additionally, also independently parameterises the weighting of parameters of the charging device 1 and the power converter 2. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 198 24 064 A1

[0002] EP 3 959 100 B1

[0003]

Claims

[1] Method for determining a load index of a power converter (2) as part of a charging device (1) for electrically operated vehicles, with a power converter (2) which has a power electronic switching device (3) and a control device (4) therefor, wherein a protocol device (5) stores a plurality of characteristic variables of the charging device (1) and in particular of the power converter (2), with an evaluation device (6) which evaluates the plurality of characteristic variables and determines the load index therefrom and, when a first threshold value of the load index is reached, transmits this information to a first higher-level decision device (7). [2] Method according to claim 1, wherein the parameters are selected in particular from: • Time course of the voltage at input 20 of the power converter 2 • Time course of the current at input 20 of the power converter 2 • Network utilization • Number of charging processes • Duration of each charging process • Time course of the charging current of the respective charging process • temporal progression of the charging voltage of the respective charging process • Overvoltages within the power electronic circuit • Temperature of converter components • Back pressure of a cooling device • Temperature at the outlet of the cooling device • Speed ​​of a cooling fan • Ambient temperature • Relative humidity of the environment • Fine dust concentration in the environment. [3] Method according to one of the preceding claims, wherein when a second threshold value of the load index is reached, this information is transmitted to a second higher-level decision device. [4] Method according to one of the preceding claims, wherein the data of the protocol device (5) are transmitted completely or selectively to a third higher-level decision device. [5] Method according to one of the preceding claims, wherein the respective evaluations of the evaluation device (6) are transmitted completely or selectively to a fourth higher-level decision device. [6] Method according to one of the preceding claims, wherein the evaluation device (6) determines the parameters, in particular differently in each case, weighted to a respective value of the load index. [7] Method according to claim 6, wherein an M-tuple (61,62,...,6M) is determined from N parameters as the value of the load index, where M is less than or equal to N. [8] Method according to claim 6 or 7, wherein individual parameters are incorporated multiple times and preferably differently weighted into one or more components of the M-tuple (61,62,...,6M). [9] Method according to one of claims 6 to 8, wherein the weighting of the respective parameters is parameterized externally during operation. [10] Method according to one of claims 6 to 9, wherein the weighting of the respective parameters is parameterized during operation by the evaluation device (7) itself. [11] Method according to one of the preceding claims, wherein the evaluation device (7) determines the load index from additional data of other power converters or other charging devices (100). [12] Method according to claim 11, wherein the decision device (7) makes the data of other power converters or other charging devices (100) available to the evaluation device (6). [13] Method according to one of claims 6 to 12, wherein the data of other power converters or other charging devices (100) are included in the parameterization. [14] Method according to one of the preceding claims, wherein the decision device reacts on a control device (8) and thereby changes its control method of the power converter (2). [15] Device for carrying out a method according to one of the preceding claims, comprising a power converter (2) as part of a charging device (1) for electrically operated vehicles, wherein the power converter (2) has a power electronic switching device (3) and a control device (4) therefor, wherein a protocol device (5) has a data storage device, wherein an evaluation device (6) has a computing device and wherein a higher-level decision device (7) has a data transmission device. [16] Apparatus according to claim 15, wherein the loading device (1) comprises the decision device (7). [17] Device according to claim 15, wherein the decision device (7) is not formed as part of the charging device (1), but is connected to the charging device (1) via a data connection, preferably a cloud connection.

Images