Electronic control unit and diagnostic method for electronic control unit

Abstract

Provided is an electronic control device equipped with an excitation amplifier for outputting an excitation signal to a resolver, a micro-controller, and a power supply IC, the electronic control device being highly reliable and capable of diagnosing an abnormality of the excitation amplifier before system activation and during operation. The electronic control device comprises a power supply IC, a micro-controller which is supplied with a power supply voltage from the power supply IC, an excitation amplifier for exciting a resolver, and a diagnostic circuit for diagnosing an abnormality by monitoring an input signal and an output signal of the excitation amplifier, characterized in that the diagnostic circuit performs the abnormality diagnosis of the excitation amplifier by comparing the input signal and the output signal, and transmits the diagnosis result to the micro-controller.

Description

[Technical field]

[0001] The present invention relates to the configuration of an electronic control device and its control, and more particularly to a technique that is effective when applied to an electronic control device equipped with an excitation amplifier that outputs an excitation signal to a resolver (rotation angle sensor). [Background technology]

[0002] In recent years, vehicles equipped with driving assistance functions that support steering and acceleration / deceleration, hybrid vehicles that run on a motor in addition to a conventional engine, and electric vehicles that run only on a motor are becoming more common. These vehicles have more complex electronic controls than conventional vehicles, and require more advanced safety controls, such as safely stopping the vehicle or restricting its operation in the event of a failure in an electronic component.

[0003] These vehicle electronic control devices perform safety controls, such as safely stopping the motor, engine, etc. via safety control signals when they detect a fault, or limiting the vehicle's speed and motor torque to allow the vehicle to continue operating. It is important to accurately detect and diagnose faults and abnormalities in the electronic components used in these electronic control devices and use them for safety control.

[0004] Incidentally, with the spread of hybrid vehicles and electric vehicles, resolvers, which play a central role in controlling the rotation of motors, are becoming increasingly important. A resolver is a rotation angle sensor that is essential for controlling a driving motor. By efficiently controlling the motor, it is possible to reduce power consumption. In order to control the motor according to the driving conditions, it is necessary to detect the magnetic pole position of the motor and grasp the accurate rotation speed, and a resolver is used as a sensor for this purpose.

[0005] Background art in this technical field includes, for example, technology such as Patent Document 1. Patent Document 1 discloses "a rotation angle detection device having an excitation signal amplitude detection unit that offsets an excitation signal of a resolver and detects the amplitude based on the offset excitation signal, an excitation signal voltage detection unit that detects the voltage of the excitation signal, and an excitation signal diagnosis unit that distinguishes an abnormal state in which the amplitude of the excitation signal is outside the normal range between a power short and a ground short of the excitation signal supply line based on the voltage of the excitation signal."

[0006] According to Patent Document 1, it is possible to diagnose an abnormal state of a supply line of an excitation signal in a resolver by distinguishing between a power fault and a ground fault. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2020-46376 A Summary of the Invention [Problem to be solved by the invention]

[0008] As mentioned above, as automotive control systems become more complex and larger in scale, the risk of the system malfunctioning when a failure occurs is increasing. If a malfunction occurs in the control function of an automotive control system, it poses danger not only to the driver and passengers but also to the entire surrounding area, including pedestrians. Therefore, it is important to improve the reliability of the individual components that make up the system, as well as the reliability of the safety control function that detects and responds to system abnormalities.

[0009] The technology described in the above Patent Document 1 makes it possible to detect obvious abnormalities such as power faults, ground faults, and disconnections in the excitation signal output from the excitation amplifier to the resolver. However, it is difficult to detect failures or abnormalities in the excitation amplifier that lead to changes in characteristics such as the frequency, amplitude, and phase of the excitation signal.

[0010] Therefore, an object of the present invention is to provide a highly reliable electronic control device and a diagnostic method for an electronic control device that is equipped with an excitation amplifier that outputs an excitation signal to a resolver, a microcomputer, and a power supply IC, and that is capable of diagnosing an abnormality in the excitation amplifier before the system is started up and during operation. [Means for solving the problem]

[0011] In order to solve the above problems, the present invention provides an electronic control device including a power supply IC, a microcomputer to which a power supply voltage is supplied from the power supply IC, an excitation amplifier for exciting a resolver, and a diagnostic circuit for diagnosing an abnormality by monitoring an input signal and an output signal of the excitation amplifier, the excitation amplifier and the diagnostic circuit being built into the power supply IC, After the system is powered on The input signal and the output signal are outputted from the power supply IC after the power supply IC is started and before the electronic control device is started. For frequency, amplitude, and delay information and transmits the diagnosis result to the microcomputer. If the diagnosis result confirms a frequency abnormality and the input frequency is abnormal, the microcomputer determines that the cause of the abnormality is something other than the excitation amplifier, and if the diagnosis result confirms a frequency abnormality and the output frequency is abnormal, or if an amplitude abnormality is confirmed, or if a delay abnormality is confirmed, the microcomputer determines that the excitation amplifier is abnormal. It is characterized by:

[0012] The present invention also provides a diagnostic method for an electronic control device, the electronic control device including an excitation amplifier that outputs an excitation signal to a resolver, a microcomputer, and a power supply IC, the excitation amplifier and a diagnostic circuit that performs abnormality diagnosis for the excitation amplifier being built into the power supply IC, comprising: After the system is powered on The input signal and the output signal of the excitation amplifier are monitored during the period from after the power supply IC is started until before the electronic control device is started, and the input signal and the output signal are For frequency, amplitude, and delay information and transmits the diagnosis result to the microcomputer. If the diagnosis result confirms a frequency abnormality and is an input frequency abnormality, it is determined that the cause of the abnormality is something other than the excitation amplifier. If the diagnosis result confirms a frequency abnormality and is an output frequency abnormality, or if an amplitude abnormality is confirmed, or if a delay abnormality is confirmed, it is determined that the excitation amplifier is abnormal. It is characterized by: Effect of the Invention

[0013] According to the present invention, in an electronic control device equipped with an excitation amplifier that outputs an excitation signal to a resolver, a microcomputer, and a power supply IC, it is possible to realize a highly reliable electronic control device and a diagnostic method for an electronic control device that are capable of diagnosing an abnormality in the excitation amplifier before the system is started up and during operation.

[0014] This makes it possible to detect an abnormality in the electronic control device before the vehicle is started and during operation, enabling safe control of the vehicle in response to the abnormality.

[0015] Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0016] [Figure 1] 1 is a block diagram of an electronic control device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram of the diagnostic circuit of FIG. 1. [Diagram 3] 3 is a block diagram of a frequency comparison unit in FIG. 2. [Figure 4] 3 is a block diagram of an amplitude comparison unit in FIG. 2. [Diagram 5] 3 is a block diagram of a delay (phase) comparison unit in FIG. 2. [Figure 6] FIG. 11 is a block diagram of an electronic control device according to a second embodiment of the present invention. [Figure 7] FIG. 11 is a block diagram of an electronic control device according to a third embodiment of the present invention. [Figure 8] 8 is a flowchart showing a diagnostic method for the electronic control unit of FIG. 7 before the system is started up. [Figure 9] 8 is a flowchart showing a diagnostic method during system operation of the electronic control unit of FIG. 7. [Figure 10] FIG. 11 is a block diagram of an electronic control device according to a fourth embodiment of the present invention. [Figure 11] FIG. 11 is a block diagram of an electronic control device according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same components are designated by the same reference numerals, and detailed description of overlapping parts will be omitted. EXAMPLES

[0018] <Configuration of electronic control device> An electronic control device and a diagnostic method thereof according to a first embodiment of the present invention will be described with reference to Fig. 1 to Fig. 5. Fig. 1 is a block diagram showing the internal configuration of the electronic control device of this embodiment.

[0019] As shown in FIG. 1, the electronic control device 1 of this embodiment is composed of a microcontroller (hereinafter, referred to as a microcomputer) 2, a power supply IC (Integrated Circuit) 3, an RDC-IC (Resolver-Digital Converter IC) 4, an excitation amplifier 5, and a diagnostic circuit 6.

[0020] The microcomputer 2 is the brain of the electronic control device 1, and controls the power supply IC 3 and the RDC-IC 4 using the first communication control signal and the second communication control signal. For example, by communicating with the power supply IC 3 via the first communication control signal, the microcomputer 2 can change the settings of the power supply IC 3, transmit its own status to the power supply IC 3, and check the status of the power supply IC 3. Also, the microcomputer 2 can change the settings of the RDC-IC 4 and output an input signal for the excitation amplifier 5 via the second communication control signal.

[0021] The power supply IC 3 generates multiple power supply voltages from a battery voltage (not shown) and supplies the power supply voltages to the microcomputer 2, the RDC-IC 4, the excitation amplifier 5, the diagnostic circuit 6, and other peripheral circuits (not shown) inside the electronic control device. Here, power supply voltage outputs 1 to 4 are shown, but the number and destination of the power supply voltage outputs may be different. In addition, the power supply IC 3 outputs a reset signal to the microcomputer 2 when a system reset is required, such as when power is supplied to the electronic control device 1.

[0022] The RDC-IC4 is an IC that performs calculations using angle signals (COS+, COS-, SIN+, SIN-) that change depending on the rotation angle of the motor rotor and are output from a resolver 7, which is a rotation angle sensor attached to a motor (not shown) that detects the rotation angle of the motor, and converts the motor rotation angle into digital data. The RDC-IC4 transmits the motor rotation angle information obtained by calculation to the microcomputer 2 via an angle information signal.

[0023] The excitation amplifier 5 is an amplifier that amplifies the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5 output from the RDC-IC 4, and generates excitation signals (EXC+, EXC-) for exciting the resolver 7. Although an example using differential signals is shown here, a single-ended configuration may also be used.

[0024] The diagnostic circuit 6 compares the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5 with the excitation signals (EXC+, EXC-), which are the output signals, to diagnose an abnormality in the excitation amplifier 5. The result of the abnormality diagnosis of the excitation amplifier 5 obtained by comparing the input and output signals of the excitation amplifier 5 is transmitted to the microcomputer 2 using a third communication control signal. Depending on the abnormality diagnosis result of the excitation amplifier 5 transmitted from the diagnostic circuit 6, the microcomputer 2 performs appropriate safety control that is preset for the electronic control device 1.

[0025] <Internal configuration of diagnostic circuit> Fig. 2 is a block diagram showing the internal configuration of the diagnostic circuit 6 of Fig. 1. How the diagnostic circuit 6 diagnoses an abnormality in the excitation amplifier 5 will be described with reference to Fig. 2.

[0026] The diagnostic circuit 6 is made up of a frequency comparison section 10, an amplitude comparison section 11, a delay (phase) comparison section 12, and a communication interface circuit 13.

[0027] The excitation signals (EXCIN+, EXCIN-) which are input signals to the excitation amplifier 5, and the excitation signals (EXC+, EXC-) which are output signals from the excitation amplifier 5 are input to a frequency comparison unit 10, an amplitude comparison unit 11, and a delay (phase) comparison unit 12, respectively, and processing is performed inside each comparison unit, and the abnormality diagnosis result of the excitation amplifier 5 is output to the communication interface circuit.

[0028] In FIG. 2, the diagnostic circuit 6 is equipped with a frequency comparison section 10, an amplitude comparison section 11, and a delay (phase) comparison section 12. However, it is possible to diagnose the excitation amplifier 5 with at least one of these comparison sections, and it is also possible to use a combination of a plurality of these comparison sections.

[0029] <Internal structure of frequency comparison section> Fig. 3 is a block diagram showing an example of the internal configuration of the frequency comparing section 10 of Fig. 2. How the frequency comparing section 10 diagnoses an abnormality in the excitation amplifier 5 will be described with reference to Fig. 3.

[0030] The input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5 are input to the frequency comparison unit 10. The input signals (EXCIN+, EXCIN-) of the excitation amplifier 5 are measured by an input frequency counter 21, and the excitation signals (EXC+, EXC-) are measured by an output frequency counter 22.

[0031] The frequency measurement results are outputted to the outside of the frequency comparing unit 10 as an input frequency measurement result and an output frequency measurement result. Furthermore, the input frequency measurement result and the output frequency measurement result are compared with a frequency setting value 25 in an input frequency comparing unit 23 and an output frequency comparing unit 24, respectively.

[0032] The comparison results from the input frequency comparison unit 23 and the output frequency comparison unit 24 are input to a frequency diagnosis unit 26, which detects abnormalities in the input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5 and diagnoses the excitation amplifier 5.

[0033] From the above, in the frequency comparison unit 10, when there is an abnormality in the frequency of the excitation signals (EXCIN+, EXCIN-) which are input signals to the excitation amplifier 5, it is possible to determine that an abnormality has occurred in a stage preceding the excitation amplifier 5. Also, when there is an abnormality in the frequency of the excitation signals (EXC+, EXC-) which are output signals from the excitation amplifier 5, it is possible to determine that there is an abnormality in the excitation amplifier 5 itself.

[0034] The configuration described here is merely an example, and other configurations may be used as long as they can realize the functions of the frequency comparing section 10 described above.

[0035] <Internal structure of the amplitude comparison section> Fig. 4 is a block diagram showing an example of the internal configuration of the amplitude comparison unit 11 in Fig. 2. How the amplitude comparison unit 11 diagnoses an abnormality in the excitation amplifier 5 will be described with reference to Fig. 4.

[0036] The input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5 are input to the amplitude comparison unit 11. The input signals (EXCIN+, EXCIN-) of the excitation amplifier 5 are measured by an input signal voltage detection unit 31, and the excitation signals (EXC+, EXC-) are measured by an output signal voltage detection unit 32.

[0037] The voltage measurement results are output as an input amplitude measurement result and an output amplitude measurement result to the outside of the amplitude comparison unit 11. In addition, the input amplitude measurement result and the output amplitude measurement result are used in a gain calculation unit 33 to calculate the gain from the input signal (EXCIN+, EXCIN-) of the excitation amplifier 5 to the excitation signal (EXC+, EXC-).

[0038] The calculated gain value is compared with a gain setting value 35 in a gain comparison unit 34. Using the result of this comparison, an amplitude diagnosis unit 36 ​​detects an abnormality in the excitation signals (EXC+, EXC-) and performs diagnosis of the excitation amplifier 5.

[0039] From the above, the amplitude comparison unit 11 can diagnose whether the excitation signals (EXC+, EXC-) are amplified with a desired gain with respect to the input amplitude of the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5.

[0040] Furthermore, the input amplitude measurement result is output to the outside of the amplitude comparison unit 11, and the third communication control signal from the diagnosis circuit 6 enables the microcomputer 2 to detect an abnormality in the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5.

[0041] The configuration described here is merely an example, and other configurations may be used as long as they can realize the functions of the amplitude comparing section 11 described above.

[0042] <Internal configuration of delay (phase) comparison section> Fig. 5 is a block diagram showing an example of the internal configuration of the delay (phase) comparison unit 12 of Fig. 2. How the delay (phase) comparison unit 12 diagnoses an abnormality in the excitation amplifier 5 will be described with reference to Fig. 5.

[0043] The input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5 are input to the delay (phase) comparison unit 12. The input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5 are input to a phase comparator 41, which detects the delay amount (phase shift amount) of the input signals (EXCIN+, EXCIN-) and excitation signals (EXC+, EXC-) of the excitation amplifier 5.

[0044] The amount of delay (amount of phase shift) detected by the phase comparator 41 is output as a delay (phase) measurement result to the outside of the delay (phase) comparison unit 12. In addition, the delay (phase) measurement result is compared with a phase shift allowable value 43 in a phase shift comparison unit .

[0045] Using the result of this comparison, the delay (phase) diagnostic unit 44 detects an abnormality between the input signals (EXCIN+, EXCIN−) of the excitation amplifier 5 and the excitation signals (EXC+, EXC−) and performs a diagnosis of the excitation amplifier 5.

[0046] From the above, when the delay (phase) comparison unit 12 detects an abnormal delay (phase shift) between the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5 and the excitation signals (EXC+, EXC-), it is possible to determine that there is an abnormality in the excitation amplifier 5 itself.

[0047] The configuration described here is merely an example, and other configurations may be used as long as they can realize the functions of the delay (phase) comparison section 12 described above. EXAMPLES

[0048] <Example of RDC-IC function installed in a microcontroller> Second Embodiment An electronic control device according to a second embodiment of the present invention will be described with reference to Fig. 6. Fig. 6 is a block diagram showing the internal configuration of the electronic control device of this embodiment.

[0049] An electronic control device 1A of this embodiment is made up of a microcomputer 2A incorporating an angle detection unit 8, a power supply IC 3, an excitation amplifier 5, and a diagnostic circuit 6, as shown in FIG.

[0050] The difference from the first embodiment is that the microcomputer has a built-in RDC-IC function. The microcomputer 2A outputs a digital signal (EXCIN_DIG), and a DAC (Digital-Analog Converter) 9 converts the digital signal (EXCIN_DIG) to an analog signal and outputs an input signal (EXCIN+, EXCIN-) for the excitation amplifier 5. The excitation amplifier 5 outputs an excitation signal (EXC+, EXC-) to the resolver 7.

[0051] The resolver 7 outputs angle signals (COS+, COS-, SIN+, SIN-) that change depending on the rotation angle of the rotor of a motor (not shown). The microcomputer 2A receives the angle signals (COS+, COS-, SIN+, SIN-) in the built-in angle detection unit 8 and detects the rotation angle of the motor by calculation.

[0052] Other operations and controls of the electronic control device 1A are the same as those of the first embodiment.

[0053] Here, the microcomputer 2A outputs a digital signal (EXCIN_DIG), but if the microcomputer 2A can directly output an analog signal, it may output the input signal (EXCIN+, EXCIN-) of the excitation amplifier 5 directly to the excitation amplifier 5 without using the DAC 9. EXAMPLES

[0054] <An example where the RDC-IC function is implemented in a microcontroller, and the excitation amplifier and diagnostic circuit are implemented in a power supply IC> Third embodiment An electronic control device and a diagnostic method thereof according to a third embodiment of the present invention will be described with reference to Fig. 7 to Fig. 9. Fig. 7 is a block diagram showing the internal configuration of the electronic control device of this embodiment.

[0055] As shown in FIG. 7, an electronic control device 1B of this embodiment is made up of a microcomputer 2A incorporating an angle detection unit 8, and a power supply IC 3A incorporating an excitation amplifier 5A and a diagnostic circuit 6A.

[0056] The difference from the first embodiment is that the microcomputer has the RDC-IC function built in, and the power supply IC has an excitation amplifier and a diagnostic circuit built in. The microcomputer 2A outputs a digital signal (EXCIN_DIG), and the DAC 9 converts the digital signal (EXCIN_DIG) to an analog signal and outputs the input signal (EXCIN+, EXCIN-) of the excitation amplifier 5A built in the power supply IC 3A, and the excitation amplifier 5A outputs the excitation signal (EXC+, EXC-) to the resolver 7.

[0057] The resolver 7 outputs angle signals (COS+, COS-, SIN+, SIN-) that change depending on the rotation angle of the rotor of a motor (not shown). The microcomputer 2A receives the angle signals (COS+, COS-, SIN+, SIN-) in an internal angle detection unit 8 and detects the rotation angle of the motor by calculation.

[0058] The diagnostic circuit 6A built into the power supply IC 3A is used to compare the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A with the excitation signals (EXC+, EXC-), which are the output signals, to diagnose abnormalities in the excitation amplifier 5A.

[0059] The result of the abnormality diagnosis of the excitation amplifier 5A obtained by comparing the input and output signals of the excitation amplifier 5A is transmitted to the microcomputer 2A using the third communication control signal. Depending on the abnormality diagnosis result of the excitation amplifier 5A transmitted from the diagnostic circuit 6A, the microcomputer 2A can perform safety control such as stopping the motor or limiting the torque of the motor for the electronic control device 1A according to the contents of a preset program.

[0060] Here, the microcomputer 2A outputs a digital signal (EXCIN_DIG), but if the microcomputer 2A can directly output an analog signal, it may output the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A directly to the excitation amplifier 5A without using the DAC 9. Also, although the DAC 9 is arranged outside the power supply IC 3A, it may be built into the power supply IC 3A.

[0061] <Excitation amplifier diagnosis before system startup> FIG. 8 is a flowchart for a case where an abnormality diagnosis of the excitation amplifier 5A is performed before the system is started in the electronic control device 1B of FIG.

[0062] When power is supplied to the electronic control device 1B (step S100), the power supply IC 3A starts to start up (step S101). When started up, the power supply IC 3A generates a power supply voltage output to be supplied to each component of the electronic control device 1B and issues a reset signal to the microcomputer 2A (step S102).

[0063] Then, the microcomputer 2A is initialized and starts an initial diagnosis of each part of the electronic control device 1B (step S103). When the initial diagnosis starts, the diagnostic circuit 6A starts a diagnostic operation of the excitation amplifier 5A (step S104), and the microcomputer 2A outputs the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A (step S105).

[0064] Then, the excitation amplifier 5A outputs excitation signals (EXC+, EXC-) which are output signals corresponding to the input signals to the resolver 7 (step S106). During this time, the diagnostic circuit 6A uses the input and output signals of the excitation amplifier 5A to diagnose abnormalities in the excitation amplifier, and outputs the diagnosis result (step S107).

[0065] If no particular abnormality is found (NO in step S108), the microcomputer 2A starts normal system startup of the electronic control device 1B (step S109).

[0066] Conversely, if an abnormality is found (YES in step S108), a determination is made as to whether the abnormality is a frequency abnormality (step S110), an amplitude abnormality (step S111), or a delay (phase) abnormality (step S112).

[0067] If a frequency abnormality is confirmed and it is found to be an input frequency abnormality (YES in step S113), the microcomputer 2A determines that the cause of the abnormality is other than that of the excitation amplifier 5A (step S117).

[0068] On the other hand, if an abnormality in the output frequency, amplitude, or delay (phase) is confirmed, the microcomputer 2A determines that an abnormality exists in the excitation amplifier 5A (step S114).

[0069] Regardless of whether the microcomputer 2A determines that there is an abnormality in the excitation amplifier 5A or in a device other than the excitation amplifier 5A, the microcomputer 2A records the diagnosis result in a memory, a register, or the like (step S115).

[0070] Thereafter, the microcomputer 2A uses the diagnosis result to implement safety control such as halting system startup or starting the system after imposing restrictions (step S116).

[0071] This safety control can implement different controls, such as stopping the motor or limiting the torque of the motor, according to a program previously set in the microcomputer 2A or the like.

[0072] From the above, it becomes possible to diagnose an abnormality in the excitation amplifier 5A before starting up the electronic control device 1B, and to implement safety control if an abnormality is confirmed.

[0073] <Excitation amplifier diagnosis during system operation> FIG. 9 is a flowchart for a case where an abnormality diagnosis is performed on the excitation amplifier 5A during system operation in the electronic control device 1B of FIG.

[0074] During system operation, the power supply IC 3A constantly diagnoses the microcontroller 2A (step S200) and checks whether there is an abnormality in the microcontroller 2A (step S201). If there is an abnormality in the microcontroller 2A (YES in step S201), the power supply IC 3A performs safety control such as stopping the motor, issuing a microcontroller reset signal, and stopping the excitation amplifier 5A (step S202).

[0075] This safety control can change the control content, such as stopping the motor or limiting the torque of the motor, depending on the settings previously made in the power supply IC 3A.

[0076] Here, the power supply IC 3A performs abnormality diagnosis of the microcomputer 2A based on a watchdog timer, a clock monitor value periodically received from the microcomputer, and direct error signal reception from the microcomputer 2A.

[0077] Also, if there is no abnormality in the microcomputer 2A (determined as NO in step S201), when the microcomputer 2A detects an angle detection error in the angle detection unit 8 (determined as YES in step S203), the microcomputer 2A checks the diagnosis result of the diagnostic circuit 6A (step S204).

[0078] If no abnormality is found in the checks for frequency abnormality (step S205), amplitude abnormality (step S206), and delay (phase) abnormality (step S207), the microcomputer 2A determines that there is an abnormality other than in the excitation amplifier 5A (step S208), and executes corrective action using information other than the diagnosis result of the diagnostic circuit 6A (step S209).

[0079] Furthermore, if an abnormality is found in any of the frequency abnormality check (step S205), amplitude abnormality check (step S206), and delay (phase) abnormality check (step S207), the microcomputer 2A diagnoses that the excitation amplifier 5A is faulty (step S210) and executes safety control such as safely stopping the system (step S211). The content of this safety control can be changed by settings previously applied to the microcomputer 2A, etc.

[0080] Furthermore, in step S203, if the microcomputer 2A does not detect an angle detection error in the angle detection unit 8, the microcomputer 2A also checks the diagnosis result of the diagnosis circuit 6A in the same manner (step 212).

[0081] If no abnormality is found in the checks for frequency abnormality (step S213), amplitude abnormality (step S214), and delay (phase) abnormality (step S215), the microcomputer 2A allows the system to continue normal operation (step S216).

[0082] Conversely, if an abnormality is found in any of the frequency abnormality check (step S213), amplitude abnormality check (step S214), and delay (phase) abnormality check (step S215), the microcomputer 2A diagnoses that the excitation amplifier 5A is faulty (step S217) and executes safety control such as safely stopping the system (step S218). The content of this safety control can be changed by settings previously applied to the microcomputer 2A, etc. EXAMPLES

[0083] <Example of a power supply IC equipped with an excitation amplifier and diagnostic circuit> Fourth embodiment An electronic control device and a diagnostic method thereof according to the present invention will be described with reference to Fig. 10. Fig. 10 is a block diagram showing the internal configuration of the electronic control device of this embodiment.

[0084] As shown in FIG. 10, an electronic control device 1C of this embodiment is made up of a microcomputer 2, an RDC-IC 4, and a power supply IC 3B incorporating an excitation amplifier 5A and a diagnostic circuit 6A.

[0085] The difference from the first embodiment is that the power supply IC 3B has an excitation amplifier 5A and a diagnostic circuit 6A built in. The RDC-IC 4 outputs input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A built in the power supply IC 3B, and the excitation amplifier 5 outputs excitation signals (EXC+, EXC-) to the resolver 7.

[0086] The resolver 7 outputs angle signals (COS+, COS-, SIN+, SIN-) that change depending on the rotation angle of the rotor of a motor (not shown). The RDC-IC 4 performs calculations using the angle signals (COS+, COS-, SIN+, SIN-) to detect the rotation angle of the motor and transmits the information to the microcomputer 2 as an angle information signal.

[0087] The diagnostic circuit 6A built into the power supply IC 3B is used to compare the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A with the excitation signals (EXC+, EXC-) which are the output signals, to diagnose abnormalities in the excitation amplifier 5A.

[0088] The result of the abnormality diagnosis of the excitation amplifier 5A obtained by comparing the input and output signals of the excitation amplifier 5A is transmitted to the microcomputer 2 using the third communication control signal. The microcomputer 2 performs appropriate safety control that is preset for the electronic control device 1C according to the result of the abnormality diagnosis of the excitation amplifier 5A transmitted from the diagnostic circuit 6A. EXAMPLES

[0089] <Example where the excitation amplifier input signal is output from a microcontroller, and the excitation amplifier and diagnostic circuit are mounted on the power supply IC> Fifth embodiment An electronic control device and a diagnostic method thereof according to a fifth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is a block diagram showing the internal configuration of the electronic control device of this embodiment.

[0090] As shown in FIG. 11, an electronic control device 1D of this embodiment is made up of a microcomputer 2B, an RDC-IC 4A, and a power supply IC 3B incorporating an excitation amplifier 5A and a diagnostic circuit 6A.

[0091] This embodiment is a modified example of the fourth embodiment, and differs from the fourth embodiment in that the microcomputer 2B outputs a digital signal (EXCIN_DIG), the DAC 9 converts the digital signal (EXCIN_DIG) into an analog signal, and generates and outputs input signals (EXCIN+, EXCIN-) for the excitation amplifier 5A built in the power supply IC 3B.

[0092] The excitation amplifier 5A outputs excitation signals (EXC+, EXC-) to the resolver 7. The resolver 7 outputs angle signals (COS+, COS-, SIN+, SIN-) that change depending on the rotation angle of the rotor of a motor (not shown), and the RDC-IC 4A performs calculations using the angle signals (COS+, COS-, SIN+, SIN-) to detect the rotation angle of the motor and transmits the information to the microcomputer 2 as an angle information signal.

[0093] The diagnostic circuit 6A built into the power supply IC 3B is used to compare the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A with the excitation signals (EXC+, EXC-) which are the output signals, to diagnose an abnormality in the excitation amplifier 5A.

[0094] The result of the abnormality diagnosis of the excitation amplifier 5A obtained by comparing the input and output signals of the excitation amplifier 5A is transmitted to the microcomputer 2B using the third communication control signal. The microcomputer 2B performs appropriate safety control that is preset for the electronic control device 1D according to the result of the abnormality diagnosis of the excitation amplifier 5A transmitted from the diagnostic circuit 6A.

[0095] Here, the microcomputer 2B outputs a digital signal (EXCIN_DIG), but if the microcomputer 2B can directly output an analog signal, it may output the input signals (EXCIN+, EXCIN-) of the excitation amplifier 5A directly to the excitation amplifier 5A without using the DAC 9. Also, although the DAC 9 is arranged outside the power supply IC 3B, it may be built into the power supply IC 3B.

[0096] In each of the above-described embodiments, the control lines and information lines are those that are considered necessary for the explanation, and not all of the control lines and information lines in the product are necessarily shown.

[0097] In addition, in each of the above-mentioned embodiments, the configuration of the functional blocks is merely an example. Some functional configurations shown as separate functional blocks may be integrated, or a configuration shown in one functional block diagram may be divided into two or more functions. In addition, some of the functions of each functional block may be provided by other functional blocks.

[0098] In addition, the above-mentioned embodiments may be combined with each other. Although various embodiments have been described above, the present invention is not limited to these. Other embodiments that are conceivable within the scope of the technical idea of ​​the present invention are also included in the scope of the present invention. [Explanation of symbols]

[0099] 1, 1A, 1B, 1C, 1D...Electronic control device, 2, 2A, 2B...Microcontroller, 3, 3A, 3B...Power supply IC, 4, 4A...RDC-IC, 5, 5A...Excitation amplifier, 6, 6A...Diagnostic circuit, 7...Resolver, 8...Angle detection unit, 9...DAC (Digital-Analog Converter), 10... frequency comparison section, 11... amplitude comparison section, 12... delay (phase) comparison section, 13... communications interface circuit, 21... input frequency counter, 22... output frequency counter, 23... input frequency comparison section, 24... output frequency comparison section, 25... frequency setting value, 26... frequency diagnosis section, 31... input signal voltage detection section, 32... output signal voltage detection section, 33... gain calculation section, 34... gain comparison section, 35... gain setting value, 36... amplitude diagnosis section, 41... phase comparator, 42... phase shift comparison section, 43... phase shift tolerance, 44... delay (phase) diagnosis section

Claims

1. A power supply IC; a microcomputer to which a power supply voltage is supplied from the power supply IC; An excitation amplifier that excites the resolver; A diagnostic circuit that monitors an input signal and an output signal of the excitation amplifier to diagnose an abnormality, the excitation amplifier and the diagnostic circuit are built into the power supply IC; the diagnostic circuit performs an abnormality diagnosis of the excitation amplifier by comparing frequency, amplitude, and delay information of the input signal and the output signal during a period between the start-up of the power supply IC after the system power is turned on and the start-up of the electronic control device, and transmits the diagnosis result to the microcomputer; When a frequency abnormality is confirmed in the diagnosis result and the input frequency is abnormal, the microcomputer determines that the cause of the abnormality is other than the excitation amplifier, An electronic control device that determines that there is an abnormality in the excitation amplifier when a frequency abnormality is confirmed and the output frequency is also abnormal, or when an amplitude abnormality is confirmed, or when a delay abnormality is confirmed.

2. 2. The electronic control device according to claim 1, the microcomputer transmits a diagnostic input signal to the excitation amplifier after the system power is turned on; The excitation amplifier outputs a diagnostic excitation signal based on the diagnostic input signal, the diagnostic circuit performs an abnormality diagnosis of the excitation amplifier by comparing the diagnostic input signal with the diagnostic excitation signal, and transmits the diagnosis result to the microcomputer; The microcomputer is an electronic control device that performs a normal system startup when the diagnostic result is normal, and executes processing corresponding to the abnormality when the diagnostic result is abnormal.

3. 3. The electronic control device according to claim 2, The diagnostic circuitry continues to operate even during system operation; When the diagnostic circuit detects an abnormality in the microcomputer, the diagnostic circuit executes a process corresponding to the abnormality. An electronic control device in which, when the diagnostic circuit determines that there is no abnormality in the microcontroller and the diagnostic result received by the microcontroller determines that there is an abnormality, the microcontroller executes processing corresponding to the abnormality.

4. A diagnostic method for an electronic control device, comprising: an excitation amplifier for outputting an excitation signal to a resolver; a microcomputer; and a power supply IC; and the excitation amplifier and a diagnostic circuit for diagnosing an abnormality of the excitation amplifier are built into the power supply IC, the method comprising: After the system power is turned on and after the power supply IC is started and before the electronic control device is started, an input signal and an output signal of the excitation amplifier are monitored, and an abnormality diagnosis of the excitation amplifier is performed by comparing frequency, amplitude, and delay information of the input signal and the output signal, and the diagnosis result is transmitted to the microcomputer. If the diagnosis result indicates that the frequency is abnormal and that the input frequency is abnormal, it is determined that the cause of the abnormality is something other than the excitation amplifier. A diagnostic method for an electronic control device that determines that there is an abnormality in the excitation amplifier if a frequency abnormality is confirmed and the output frequency is also abnormal, or if an amplitude abnormality is confirmed, or if a delay abnormality is confirmed.

5. A diagnostic method for an electronic control device according to claim 4, comprising: the microcomputer transmits a diagnostic input signal to the excitation amplifier after the system power is turned on; The excitation amplifier outputs a diagnostic excitation signal based on the diagnostic input signal, performing an abnormality diagnosis of the excitation amplifier by comparing the diagnostic input signal and the diagnostic excitation signal, and transmitting the diagnosis result to the microcomputer; A diagnostic method for an electronic control device, in which the microcomputer performs a normal system startup if the diagnostic result is normal, and executes processing corresponding to the abnormality if the diagnostic result is abnormal.

6. A diagnostic method for an electronic control device according to claim 5, comprising: When an abnormality in the microcomputer is detected during system operation, the system executes a process corresponding to the abnormality. A diagnostic method for an electronic control device, in which when the microcomputer is determined to be in a state where there is no abnormality and the diagnostic result received by the microcomputer is determined to be abnormal, the microcomputer executes processing corresponding to the location of the abnormality.

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