Method for predictive maintenance of a distribution module

Abstract

The invention relates to a method for predictive maintenance of a distribution module (2) for distributing electrical power in a vehicle (1), wherein the distribution module (2) comprises a number of electrical switches (2.1 to 2.n). According to the invention, it is provided that - a temperature value of each electrical switch (2.1 to 2.n) of the distribution module (2) is continuously recorded and the recorded temperature value is supplied to a control unit (3), - by means of an algorithm stored in the control unit (3), a temperature difference between a temperature value recorded at the start of operation and a further temperature value recorded after a specified standstill period is determined as a reference temperature value, and a moving average of the temperature difference for each of the electrical switches (2.1 to 2.n) is calculated over a specified period, wherein - if it is determined that the moving average exceeds a predetermined threshold compared to a moving average of a previous period of the same electrical switch (2.1 to 2.n), an anomaly of this electrical switch (2.1 to 2.n) is detected.

Description

[0001] The invention relates to a method for predictive maintenance of a distribution module for distributing electrical power in a vehicle, wherein the distribution module has a number of electrical switches.

[0002] From IN 202111041705 A, a system and a method for the dynamic state estimation and prediction of objects are known. The system comprises the detection of the temperature of electrical components of a vehicle by means of a temperature sensor and the corresponding generation of an initial signal set; the reception of this signal set at a differentiator and the generation of a slope by converting the received signal set into a corresponding voltage value for each of the electrical components; the monitoring of the electrical components for faults by a monitoring unit by comparing the generated slope with a predefined reference value; and the generation of a warning signal if the generated slope exceeds the predefined reference value for a predefined period of time, whereupon the associated electronic control unit of the electrical components is deactivated.

[0003] The invention is based on the objective of providing a method for the predictive maintenance of a distribution module in a vehicle.

[0004] The problem is solved according to the invention by a method which has the features specified in claim 1.

[0005] Advantageous embodiments of the invention are the subject of the dependent claims.

[0006] A method for predictive maintenance of a distribution module for distributing electrical power in a vehicle, wherein the distribution module has a number of electrical switches, provides according to the invention that - a temperature value of each electrical switch of the distribution module is continuously recorded and the recorded temperature value is fed to a control unit, - by means of an algorithm stored in the control unit, a temperature difference between a temperature value recorded at the start of operation and a further temperature value recorded after a specified standstill period is determined as a reference temperature value, and a moving average of the temperature difference is calculated for each of the electrical switches over a specified period, whereby - if it is determined that the moving average exceeds a predetermined threshold compared to a moving average of a previous period for the same electrical switch, an anomaly of this electrical switch is detected.

[0007] By applying this method, it is possible to detect the degradation of an individual electrical switch within a distribution module at a comparatively early stage, specifically before the switch fails completely. This method can largely prevent unplanned vehicle downtime and consequential damage. As a result, driver satisfaction can be increased and costs for towing and repairs can be reduced.

[0008] Furthermore, the application of this method can simplify fault diagnosis in a workshop, especially since targeted information on the cause of the fault is available.

[0009] In particular, the process can be carried out using components already present in the vehicle.

[0010] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing.

[0011] This shows: Fig. 1 schematically a vehicle with a distribution module, a control unit, a ring buffer and a fault memory.

[0012] The single figure shows, in an exemplary and highly simplified manner, a vehicle 1 with distribution module 2, a control unit 3, a ring storage unit 4 and an error memory 5.

[0013] It is generally known that in a distribution module 2, also referred to as an electrical power distributor, electrical switches 2.1 to 2.n exhibit increased contact resistance due to aging and / or defects, regardless of their respective electrical current ratings. This increased contact resistance can result in excessive heat generation, electrical power loss, and / or potential failure.

[0014] Such a faulty electrical switch 21 to 2.n is often only detected after a failure and / or periodic maintenance of the distribution module 2, so that there is a significant risk of unplanned vehicle downtime, increased costs and safety, especially driving safety.

[0015] The following describes a procedure which provides for continuous monitoring of the electrical switches 2.1 to 2.n of the distribution module 2.

[0016] Each electrical switch 2.1 to 2.n is equipped with a temperature sensor 6.1 to 6.n, independent of the electrical current. For example, each temperature sensor 6.1 to 6.n comprises an integrated circuit. In particular, each temperature sensor 6.1 to 6.n is thermally coupled to the respective switch 2.1 to 2.n.

[0017] In one embodiment, the temperature sensors 6.1 to 6.n are integrated into the electrical switches 2.1 to 2.n, with one temperature sensor 6.1 to 6.n being integrated into each electrical switch 2.1 to 2.n. This eliminates the need to implement additional temperature sensors 6.1 to 6.n for monitoring the electrical switches 2.1 to 2.n.

[0018] Temperature sensors 6.1 to 6.n are connected via a vehicle-side digital bus system to one of the central control units 3 of the distribution module 2. The respective temperature values ​​recorded by temperature sensors 6.1 to 6.n are read by the control unit 3 and cyclically stored in the cyclic ring buffer 4. The temperature values ​​of the electrical switches 2.1 to 2.n are read by the control unit 3 at regular intervals, for example, every 100 ms, and stored in the cyclic ring buffer 4.

[0019] The procedure stipulates that after each vehicle start, a temperature reading of the respective electrical switch 2.1 to 2.n is recorded immediately after its activation using the associated temperature sensor 6.1 to 6.n. This establishes a starting temperature for each electrical switch 2.1 to 2.n. Additionally, for each electrical switch 2.1 to 2.n, a further temperature reading is determined as a reference temperature, particularly after a predetermined standstill period.

[0020] Using an algorithm stored in the control unit 3, a moving average of a temperature difference between the temperature value recorded immediately after switching on the respective electrical switch 2.1 to 2.n and the subsequent temperature value is determined for each electrical switch 2.1 to 2.n over a specified period of, for example, 7 days or 100 operating hours.

[0021] In a subsequent, and in particular following, specified period, the moving average for the temperature difference of the respective electrical switch 2.1 to 2.n is calculated again.

[0022] If it is determined that the moving average of the next predefined period is significantly higher than the previously calculated moving average, and in particular exceeds a predefined threshold, then an anomaly of this electrical switch 2.1 to 2.n of the distribution module 2 is detected. The threshold is adaptively selectable and is based on empirical values. In particular, progressive aging and / or a defect are recognized as an anomaly.

[0023] Anomaly detection can be enhanced by additional filters, for example, based on ambient temperature compensation and / or a plausibility check during load changes. If an anomaly is detected in one of the electrical switches 2.1 to 2.n of the distribution module 2, a warning message is issued in the vehicle 1 and / or a warning message is sent to an application program stored on a vehicle owner's smartphone. Alternatively or additionally, the detected anomaly is transmitted to and stored in a fault memory 5 of the vehicle 1. The anomaly of the relevant electrical switch 2.1 to 2.n stored in the fault memory 5 can then be read out by workshop personnel.

[0024] This method enables early, automated detection of degradation of a given electrical switch 2.1 to 2.n in the distribution module 2, particularly before the respective electrical switch 2.1 to 2.n fails. This allows potential consequential damage, as well as towing and / or repair costs, to be largely avoided. Reference symbol list 1 vehicle 2 distribution module 2.1 to 2.n electrical switch 3 Control unit 4 ring buffers 5 fault memory 6.1 to 6.n Temperature sensor

Claims

[1] Method for predictive maintenance of a distribution module (2) for distributing electrical power in a vehicle (1), wherein the distribution module (2) comprises a number of electrical switches (2.1 to 2.n), characterized by , that - a temperature value of each electrical switch (2.1 to 2.n) of the distribution module (2) is continuously recorded and the recorded temperature value is supplied to a control unit (3), - by means of an algorithm stored in the control unit (3), a temperature difference between a temperature value recorded at the start of operation and a further temperature value recorded after a specified standstill period is determined as a reference temperature value, and a moving average of the temperature difference for each of the electrical switches (2.1 to 2.n) is calculated over a specified period, wherein - if it is determined that the moving average exceeds a predetermined threshold compared to a moving average of a previous period of the same electrical switch (2.1 to 2.n), an anomaly of this electrical switch (2.1 to 2.n) is detected. [2] Method according to claim 1, characterized by , that the detection of the anomaly of the respective electrical switch (2.1 to 2.n) is made plausible by an additional filter. [3] Method according to claim 1 or 2, characterized by , that the temperature values ​​recorded are stored in a ring buffer (4). [4] Method according to any one of the preceding claims, characterized by, that in the event of a detected anomaly of one of the electrical switches (2.1 to 2.n) a warning message is issued in the vehicle (1) and / or a warning message is sent to an application program installed on a vehicle owner's smartphone and / or is stored in a fault memory (5) of the vehicle (1).

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