Control system for electric vehicle

Abstract

To make it possible to efficiently write and take over correction information for a device in a control system of an electric vehicle.SOLUTION: A control system for an electric vehicle comprises: at least one individual control unit that each controls a corresponding device; and a representative control unit communicatively connected to the at least one individual control unit. The representative control unit stores, for each of the at least one individual control unit, correction information for correcting control actions of the individual control unit according to an individual difference of the device. The at least one individual control unit is configured to communicate with the representative control unit to acquire the correction information stored in association with itself.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a control system for an electric vehicle. [Background technology]

[0002] Patent Document 1 discloses an inverter device. This inverter device includes an inverter circuit that adjusts the power supplied to a motor, and a control unit that controls the operation of the inverter circuit. This inverter device is configured so that, after the inverter circuit and the control unit are combined, initial value data required for controlling the inverter circuit is written to the control unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-251934 Summary of the Invention [Problem to be solved by the invention]

[0004] In the control unit described above, it is necessary to write correction information for correcting the control content of the control unit according to individual differences in the motor and inverter circuit that are the control target. In this regard, an electric vehicle is equipped with many devices, such as an inverter circuit and a battery unit, and a control unit is provided for each of these devices. In other words, an electric vehicle is equipped with many control units, and when producing an electric vehicle, it is necessary to write correction information individually for all of these control units, which increases the number of production steps. Furthermore, when performing maintenance on an electric vehicle, if a control unit is replaced, it is necessary to transfer the correction information from the previous control unit. However, it is expected that the correction information cannot be read from a previous control unit that has already failed.

[0005] In view of the above, the present specification provides a technology that allows correction information to be easily written and transferred in an electric vehicle. [Means for solving the problem]

[0006] The technology disclosed in this specification is embodied in a control system for an electric vehicle, which includes at least one individual control unit that controls a corresponding device, and a representative control unit that is communicatively connected to the at least one individual control unit.

[0007] The representative control unit stores, for each of at least one individual control unit, correction information for correcting the control content of that individual control unit in accordance with individual differences between devices. At least one individual control unit is configured to be able to communicate with the representative control unit and acquire the correction information stored in association with itself.

[0008] In the above-described configuration, correction information for the individual control units is collectively stored in the representative control unit. With this configuration, necessary correction information can be written from the representative control unit to the individual control units, for example, when the individual control units are activated for the first time. For example, during the production of an electric vehicle, even if there are multiple individual control units, the representative control unit can write corresponding correction information to each individual control unit. In other words, there is no need to individually write correction information to multiple individual control units. Alternatively, when an individual control unit is replaced during maintenance of the electric vehicle, the representative control unit can write corresponding correction information to the replaced individual control unit. This eliminates the need to forcibly read correction information from, for example, a faulty previous individual control unit. In this way, the control system of the present technology allows correction information to be easily written and inherited in one or more individual control units. [Brief explanation of the drawings]

[0009] [Figure 1]2 is a block diagram showing the configuration of an electric vehicle 2 and a control system 4. FIG. [Figure 2] 10 is a flowchart showing a procedure for inputting correction information to a representative control unit and individual control units in a production process. [Figure 3] 1 is a block diagram schematically showing the flow of correction information written in sequence from a production facility 100 to a motor control unit 24 and a battery control unit 36 ​​via a representative control unit 10. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] An electric vehicle 2 employing a control system 4 of this embodiment will be described with reference to the drawings. As an example, the control system 4 of this embodiment is a control system for controlling the operation of a plurality of devices mounted on the electric vehicle 2. The electric vehicle 2 referred to here broadly refers to a vehicle having an electric motor for driving the wheels, and includes, for example, a battery electric vehicle, a hybrid electric vehicle, a fuel cell electric vehicle, a plug-in hybrid electric vehicle, and the like.

[0011] As shown in Fig. 1, the electric vehicle 2 of this embodiment includes a battery unit 30, a power control unit 20, and a motor 40. The motor 40 is connected to the wheels of the electric vehicle 2 and is a motor for driving the wheels. Although not particularly limited, the motor 40 is a synchronous motor driven by three-phase AC power, and is provided with a rotation angle sensor 42 that detects the rotation angle of the motor 40 (more specifically, the rotation angle of the rotor).

[0012] The battery unit 30 is a power source for the electric vehicle 2 and supplies power to the motor 40. The battery unit 30 includes a plurality of battery cells 32, a pair of relays 34, and a battery control unit 36. The battery cells 32 are rechargeable battery cells, such as lithium-ion battery cells or solid-state battery cells. The plurality of battery cells 32 are electrically connected to the power control unit 20 via the pair of relays 34. The battery control unit 36 ​​monitors and controls the operation of the battery unit 30. For example, the battery control unit 36 ​​monitors various status indicators of the plurality of battery cells 32, such as the current, voltage, and temperature. The battery control unit 36 ​​can also control the operation of the pair of relays 34.

[0013] The battery control unit 36 ​​is a computer device and includes a processor 36a and a non-volatile memory 36b. The memory 36b stores correction information D2. The correction information D2 is information for correcting the control content of the battery control unit 36 ​​in accordance with individual differences present in the battery unit 30. The specific content of the correction information D2 is not particularly limited. For example, the correction information D2 of the battery unit 30 includes parameters for correcting the detection value of a sensor provided in the battery unit 30.

[0014] The power control unit 20 is interposed between the battery unit 30 and the motor 40, and controls the drive power supplied from the battery unit 30 to the motor 40. The power control unit 20 can also control the regenerative power supplied from the motor 40 to the battery unit 30. The power control unit 20 includes an inverter circuit 22 and a motor control unit 24. The inverter circuit 22 can convert DC drive power supplied from the battery unit 30 into three-phase AC power and supply it to the motor 40. The inverter circuit 22 can also convert three-phase AC regenerative power supplied from the motor 40 into DC power and supply it to the battery unit 30. The operation of the inverter circuit 22 is controlled by the motor control unit 24. The motor control unit 24 is connected to a rotation angle sensor 42, and controls the operation of the inverter circuit 22 in accordance with the torque required for the motor 40 and the value detected by the rotation angle sensor 42. This controls the operation (output torque) of the motor 40.

[0015] The motor control unit 24 is a computer device and includes a processor 24a and a non-volatile memory 24b. The memory 24b stores correction information D1. The correction information D1 is information for correcting the control content of the motor control unit 24 in accordance with individual differences present in the motor 40 (including the rotation angle sensor 42) and the inverter circuit 22. The specific content of the correction information D1 is not particularly limited. For example, in the motor 40, there is an individual difference between the actual rotation angle of the motor 40 and the detection value of the rotation angle sensor 42. Therefore, the correction information D2 of the motor control unit 24 includes a parameter for correcting the detection value of the rotation angle sensor 42.

[0016] The electric vehicle 2 further includes a representative control unit 10. The representative control unit 10 is communicatively connected to the motor control unit 24 and the battery control unit 36. The representative control unit 10 issues operation commands to the motor control unit 24 and the battery control unit 36. For example, the representative control unit 10 determines a required torque for the motor 40 in response to an accelerator operation by the user, etc., and issues the required torque to the motor control unit 24.

[0017] The representative control unit 10 is a computer device and includes a processor 10a and a non-volatile memory 10b. The memory 10b stores a plurality of pieces of correction information D1, D2, .... The plurality of pieces of correction information D1, D2, ... includes correction information D1 for the motor control unit 24 and correction information D2 for the battery control unit 36. Here, the motor control unit 24 and the battery control unit 36 ​​in this embodiment are examples of individual control units in the present technology. That is, the representative control unit 10, together with the motor control unit 24 and the battery control unit 36, configures a control system 4, which is an embodiment of the present technology. Note that the electric vehicle 2 may further be provided with other individual control units, and the plurality of pieces of correction information D1, D2, ... stored in the representative control unit 10 may further include correction information for the other individual control units.

[0018] Next, the production process of the electric vehicle 2 will be described with reference to Figures 2 and 3. In this production process, the above-mentioned correction information D1, D2, ... is written to the representative control unit 10 and the individual control units, that is, the motor control unit 24 and the battery control unit 36. Note that in Figure 2 and the following description, the motor control unit 24 and the battery control unit 36 ​​will not be distinguished from each other and may be collectively referred to as the individual control units 24, 36.

[0019] First, the representative control unit 10 acquires a plurality of pieces of correction information D1, D2, ... from the production facility 100 (S10). The memory 100b of the production facility 100 pre-stores a plurality of pieces of correction information D1, D2, ... corresponding to a plurality of devices mounted on the electric vehicle 2, including the power control unit 20 and the battery unit 30. The representative control unit 10 collectively writes the acquired plurality of pieces of correction information D1, D2, ... to the memory 10b. Next, the electric vehicle 2 is started (S12). This also starts the individual control units 24, 36. In each of the individual control units 24, 36, a write permission flag for the memory 24b, 36b is turned ON (S14).

[0020] Next, the representative control unit 10 transmits the corresponding correction information D1, D2 to the individual control units 24, 36 (S16). Simultaneously, or before or after, the individual control units 24, 36 determine whether the correction information D1, D2 stored in their own memories 24b, 36b are initial values ​​(S18). If the correction information D1, D2 stored in their own memories 24b, 36b are initial values ​​(S18: Yes), the individual control units 24, 36 write the correction information D1, D2 received from the representative control unit 10 into their own memories 24b, 36b (S22). As a result, the corresponding correction information D1, D2 is written collectively to each of the multiple individual control units 24, 36.

[0021] On the other hand, if the correction information D1, D2 stored in the memories 24b, 36b are not initial values ​​(S18: No), the individual control units 24, 36 determine whether the correction information D1, D2 received from the representative control unit 10 matches the correction information D1, D2 stored in the memories 24b, 36b (S20). If the received correction information D1, D2 matches the correction information D1, D2 stored in the memories 24b, 36b (S20: Yes), the individual control units 24, 36 end the series of processing steps shown in FIG. 2 (END). On the other hand, if they do not match (S20: No), the individual control units 24, 36 input the correction information D1, D2 received from the representative control unit 10 into their own memories 24b, 36b (S22). Then, the representative control unit 10 and the individual control units 24, 36 end the series of processing steps shown in FIG. 2 (END).

[0022] The above describes the production process of the electric vehicle 2. However, after the shipment of the electric vehicle 2, for example, the individual control units 24, 36 may malfunction, and the individual control units 24, 36 may be replaced individually. In this case, the replaced individual control units 24, 36 are started up for the first time and communicate with the representative control unit 10 for the first time, and the series of processes from step S12 to step S22 shown in FIG. 2 are executed again. This ensures that the correction information D1, D2 is written to the replaced individual control units 24, 36. This reduces the number of steps required for the transfer of the correction information D1, D2 when the individual control units 24, 36 are replaced. Furthermore, even when the representative control unit 10 is replaced, the transfer of the correction information D1, D2 in the representative control unit 10 can be efficiently performed by performing the process from step S12 to step S22 using the flow shown in FIG. 2, where the positions of the representative control unit 10 and the individual control units 24, 36 are swapped.

[0023] The number of devices mounted on the electric vehicle 2 in this embodiment is not particularly limited, and may be one or more. Also, the number of memories mounted on each control unit may be one or two or more. [Explanation of symbols]

[0024] 2: Electric vehicle, 4: Control system, 10: Representative control unit, 20: Power control unit, 22: Inverter, 24: Motor control unit, 30: Battery unit, 32: Battery cell, 34: Relay, 36: Battery control unit, 40: Motor, 42: Rotation angle sensor

Claims

[Claim 1] 1. A control system for an electric vehicle, comprising: at least one individual control unit, each controlling a corresponding device; a representative control unit communicatively connected to the at least one individual control unit; Equipped with the representative control unit stores, for each of the at least one individual control units, correction information for correcting the control content of the individual control unit in accordance with individual differences of the devices; The at least one individual control unit is configured to communicate with the representative control unit and acquire the correction information stored in association with the individual control unit. Control system.

Images