Method for teaching the power electronics of an exhaust gas turbocharger

Abstract

The invention relates to a method (1000) for teaching a power electronics (16) of a turbocharger (10) of a vehicle, wherein the turbocharger (10) comprises an electric machine, - whereby a drive motor of the vehicle is set in rotation, - after which the drive motor is switched off, and - whereby the power electronics are calibrated after the drive motor is switched off. The invention enables a cost-effective replacement of components of the turbocharger, in particular its power electronics (16).

Description

[0001] The present invention relates to a method for teaching a power electronics of a turbocharger of a vehicle, wherein the turbocharger comprises an electric machine. State of the art

[0002] DE 10 2008 022 911 A1 and DE 10 2019 125 658 A1 disclose a lubrication system for an exhaust gas turbocharger.

[0003] An electrically driven exhaust gas turbocharger is known from DE 10 2018 132 191 A1 and US 2012 / 0 191 322 A1.

[0004] US 6 871 499 B1 and DE 101 40 944 A1 describe a lubrication system for an internal combustion engine. Disclosure of the invention

[0005] Electrically driven and / or electrically assisted turbochargers typically have power electronics for controlling an electric machine of the turbocharger.

[0006] The power electronics can, for example, include an inverter to convert direct current from a vehicle battery into alternating current suitable for the electric machine.

[0007] For sustainability reasons, the power electronics should be replaceable with minimal effort, for example in the event of a defect.

[0008] The object of the present invention is therefore to offer a method by which a component of an electrically driven and / or electrically assisted turbocharger can be replaced cost-effectively.

[0009] The problem is solved by a method for teaching the power electronics of a vehicle's turbocharger, wherein the turbocharger comprises an electric machine, wherein a vehicle's drive motor is set into rotation, wherein the drive motor is then switched off, and wherein the power electronics are taught after the drive motor is switched off.

[0010] One of the underlying concepts of the invention is that after replacing a turbocharger component, the turbocharger, particularly its power electronics, typically requires relearning. Specifically, the power electronics must be adapted to the respective electric motor, for example, due to tolerances in the electric motor, and in particular, calibrated. During initial production, the turbocharger can be installed separately in a specially designed device for this purpose. This device can, for example, also provide a supply of lubricating oil during the relearning process. However, such a device usually involves high acquisition costs. It is generally not guaranteed that such a device will be available when replacing a component. Therefore, a significant portion of the effort involved in replacing the component often relates to the proper execution of the relearning process.

[0011] It is proposed that, instead of the special device used exclusively during the learning process, existing elements of the turbocharger should be used, thereby saving acquisition costs and also reducing the effort, because the turbocharger does not need to be separately installed in a special device and then removed from it again.

[0012] It is specifically proposed to set the drive motor in rotation, which would, for example, create oil pressure for lubricating the turbocharger, especially its mechanical, moving components.

[0013] Another idea is to subsequently switch off the drive motor. This interrupts the exhaust flow, for example, in the case of an internal combustion engine. The turbocharger can then be brought into the state required for the learning process without the need for a special device. In particular, these two measures ensure sufficient oil pressure, thus guaranteeing adequate lubrication of the turbocharger's moving components during the learning process. Simultaneously, they prevent the learning process from being affected by disturbances such as the exhaust flow, which could lead to incorrect or suboptimal calibration of the power electronics.

[0014] In particular, the oil pump normally installed in a vehicle can be used as usual to build up oil pressure. Connecting an additional oil pump or similar device is not necessary. The oil pump installed in the vehicle can be used because, especially in the case of internal combustion engines as traction motors, it is typically driven exclusively by the traction motor and, according to the proposed method, is indeed driven by it.

[0015] It is conceivable that the drive motor is switched off when its oil pressure reaches or exceeds a setpoint. In particular, it is conceivable that the drive motor is operated until sufficient oil pressure, corresponding to the setpoint, is built up. Then the drive motor can be switched off, for example, to interrupt the exhaust flow in the case of an internal combustion engine used as the drive motor.

[0016] The drive motor can be brought up to 1000 revolutions per minute or more. In particular, the drive motor can be brought up to rotational speeds that correspond to normal vehicle operation. This allows for a realistic training situation.

[0017] The drive motor can be replaced thermomechanically with a rotating one. This drive motor can be an internal combustion engine. Therefore, the vehicle can be a vehicle with an internal combustion engine, for example, in the form of a hybrid engine or a purely internal combustion engine.

[0018] Alternatively, it is also conceivable that the drive motor is set in motion electrically. For this purpose, especially if the vehicle is a hybrid vehicle, an electric motor within the drive motor can be activated.

[0019] The learning process can be performed when the oil pressure reaches at least a minimum oil pressure. This minimum oil pressure can be lower than the target oil pressure. For example, the minimum oil pressure might correspond to the minimum required to ensure that the moving parts of the turbocharger are just adequately lubricated.

[0020] It is conceivable, for example, that the learning process starts as soon as the target oil pressure is reached. During the learning process, the oil pressure may drop. The learning process is aborted at the latest when the oil pressure falls below the minimum oil pressure.

[0021] This procedure is particularly advantageous when performed as part of a component replacement on the turbocharger. In this case, the procedure significantly minimizes effort and costs compared to completely removing the turbocharger, installing it in a special fixture, removing it from the fixture, and reinstalling it in the vehicle.

[0022] For particularly reliable execution of the procedure, it is conceivable that the steps of the procedure are controlled by a workshop tester. The workshop tester can be part of a workshop testing system. It can include a computer that can be connected to the vehicle being serviced. For example, the computer can be configured to control the vehicle, especially the engine and the turbocharger, via an OBD II interface and / or via another interface, such as a radio interface.

[0023] The procedure can be implemented on the workshop tester using a computer-executable program code that controls the respective components of the vehicle, such as the drive motor or the turbocharger.

[0024] Further features and advantages of the invention will become apparent from the following detailed description of an embodiment of the invention with reference to the figures of the drawing, which show details essential to the invention, as well as from the claims.

[0025] The individual features can be implemented individually or in any combination in various versions of the invention. The schematic drawing illustrates exemplary embodiments of the invention, which are explained in more detail in the following description. Brief description of the drawings

[0026] They show: Fig. 1. A turbocharger in a perspective view, Fig. 2 the turbocharger according Fig. 1 in a partially exploded view and Fig. 3 a flowchart of a procedure for teaching the power electronics of a turbocharger.

[0027] To facilitate understanding of the invention, the same reference numerals are used for corresponding elements in the following description of the figures. Embodiments of the invention

[0028] Fig. Figure 1 shows a turbocharger 10 in a perspective view.

[0029] Fig. Figure 2 shows a partially exploded view of the turbocharger 10. In particular, a turbocharger 12, an exhaust manifold 14 and, in a separate representation, a power electronics unit 16 are shown.

[0030] The power electronics 16 includes, among other things, an inverter. It is designed to drive an electric machine in the charger 12.

[0031] Fig. Figure 3 shows a simplified flowchart of a procedure 1000 for teaching the power electronics 16 of the turbocharger 10. The reference symbols introduced above are used to explain the procedure 1000.

[0032] In a first step 1010 of the process 1000, a drive motor of the vehicle in which the turbocharger 10 is installed is set into rotation. This drives an oil pump of the vehicle, so that the oil pressure of a lubricating oil for the lubrication of the turbocharger 10 increases.

[0033] In step 1020, the drive motor is switched off as soon as the oil pressure reaches or exceeds a target oil pressure value. This target oil pressure value is determined to ensure that the turbocharger 10 is adequately lubricated during the subsequent learning process.

[0034] The target oil pressure can correspond to the typical oil pressure during normal vehicle operation.

[0035] After the drive motor is switched off, in step 1030 the power electronics 16 are trained with regard to the electric machine controlled by it. Reference symbol list 10 turbochargers 12 chargers 14 exhaust manifolds 16 Power Electronics 1000 procedures 1010 steps 1020 steps 1030 steps

Claims

[1] Method (1000) for teaching a power electronics (16) of a turbocharger (10) of a vehicle, wherein the turbocharger (10) comprises an electric machine, - whereby a drive motor of the vehicle is set in rotation, - after which the drive motor is switched off, and - whereby the power electronics are calibrated after the drive motor is switched off. [2] Method according to the preceding claim, characterized by , that the drive motor is switched off when the oil pressure of the drive motor reaches or exceeds a target oil pressure value. [3] Method according to any of the preceding claims, characterized by that the drive motor is brought up to 1000 revolutions per minute or more. [4] Method according to any of the preceding claims, characterized by , that the drive motor is set into rotation thermomechanically. [5] Method according to any one of the preceding claims 1 to 3, characterized by , that the drive motor is set into rotation electrically. [6] Method according to any of the preceding claims, characterized by , that the learning process is carried out when the oil pressure reaches at least a minimum oil pressure. [7] Method according to any of the preceding claims, characterized by , that the procedure (1000) is carried out as part of a component replacement on the turbocharger (10). [8] Method according to any of the preceding claims, characterized by that a workshop tester controls the method (1000) according to one of the preceding patent claims.

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