JP2004173371A - Motor controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor controller which can secure a reliability in motor drive control. <P>SOLUTION: This motor controller is equipped with an analog communication line Lc2 separately from a serial communication line Lc1. Then, the second MPU22 performs the determination about whether serial communication is performed normally or not, and when the serial communication is performed normally, it controls the drive of an electric motor 3, based on a motor command value S1 sent by the serial communication line Lc1. In the case that the serial communication is abnormal, the second MPU22 controls the drive of the electric motor 3, based on a motor command value S2 sent by the analog communication line Lc2. Therefore, even in the case that the serial communication between the first MPU and the second MPU is not performed normally, it can continue the drive control of the electric motor 3. Therefore, it can improve the reliability on the motor drive control. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a distributed motor control device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a distributed motor control device, data communication between two MPUs is performed by serial communication (hereinafter, referred to as “first conventional technology”) and parallel communication is performed. (Hereinafter, referred to as “second related art”).
[0003]
(First prior art)
First, a conventional motor control device in which data communication between two MPUs is performed by serial communication will be described. As shown in FIG. 12, for example, a motor control device 100 of an electric power steering device includes a first MPU (Micro Processing Unit) 101 that calculates a motor command value based on a steering torque T, a vehicle speed V, and the like. And a second MPU 103 for driving the motor 102 based on the motor command value calculated by the MPU 101. The serial port 101a of the first MPU 101 and the serial port 103a of the second MPU 103 are mutually connected by a serial communication line 104.
[0004]
As shown in FIG. 13A, the first MPU 101 first reads sensor signals detected by various sensors. That is, a steering torque T detected by a torque sensor (not shown) and a vehicle speed V detected by a vehicle speed sensor (not shown) are read (S501). Next, the first MPU 101 calculates a motor command value (assist command current value) based on the steering torque T and the vehicle speed V with reference to a previously stored characteristic map (S502). Then, the first MPU 101 sends the calculated motor command value (for example, 8-bit data) to the second MPU 103 via the serial communication line 104 (S503). The motor command value is sent to the second MPU 103 serially one bit at a time. Thereafter, the first MPU 101 repeats the processing of S501 to S503 every predetermined control cycle.
[0005]
On the other hand, in the second MPU 103, the following processing is performed. That is, as shown in FIG. 13B, the second MPU 103 first determines whether or not serial communication is normally performed (S601). For example, the second MPU 103 determines whether the serial communication is normal or abnormal based on a checksum or the like. Then, when it is determined that the serial communication is normally performed (YES in S601), the second MPU 103 receives the data transmitted by the serial communication line 104, that is, the motor command value (S602). The drive of the motor 102 is controlled based on the motor command value obtained.
[0006]
When it is determined that the serial communication is not normally performed (NO in S601), the second MPU 103 stops the drive control of the motor 102 (S604). If the real communication is abnormal, data transmission to the second MPU 103 is interrupted, and the second MPU 103 cannot recognize the motor command value (target value). If the motor 102 is drive-controlled in a state where the motor command value is unknown, the motor 102 may exhibit unexpected behavior. Therefore, the motor 102 is stopped. After that, the second MPU 103 repeats the processing of S601 and S602 every predetermined control cycle.
[0007]
(Second conventional technology)
Next, a conventional motor control device in which data communication between two MPUs is performed by parallel communication will be described. This second prior art motor control device differs from the first prior art in that data communication between two MPUs is performed by parallel communication. Therefore, the same components as those of the first related art are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0008]
As shown in FIG. 14, the parallel port 101b of the first MPU 101 and the parallel port 103b of the second MPU 103 are mutually connected by a parallel communication line 105. Since the motor command value is 8-bit data, the parallel communication line 105 has eight data lines D0 to D7.
[0009]
As shown in FIG. 15A, first, the first MPU 101 reads sensor signals detected by various sensors. That is, a steering torque T detected by a torque sensor (not shown) and a vehicle speed V detected by a vehicle speed sensor (not shown) are read (S701). Next, the first MPU 101 calculates a motor command value (assist command current value) based on the steering torque T and the vehicle speed V with reference to a previously stored characteristic map (S702). Then, the first MPU 101 sets the calculated motor command value in the parallel port 101b, and ends the processing. The motor command value calculated by the first MPU 101 is sent to the second MPU 103 bit by bit through the data lines D0 to D7. Thereafter, the first MPU 101 repeats the processing of S701 to S703 at every predetermined control cycle.
[0010]
On the other hand, in the second MPU 103, the following processing is performed. That is, as shown in FIG. 15B, the second MPU 103 first latches (holds), ie, receives, the motor command value sent from the first MPU 101 to the parallel port 103b (S801). Then, the second MPU 103 controls the driving of the motor 102 based on the received motor command value (S802). Thereafter, the second MPU 103 repeats the processing of S801 and S802 at every predetermined control cycle.
[0011]
[Problems to be solved by the invention]
(First prior art)
However, in the conventional motor control device in which data communication between two MPUs is performed by serial communication, the drive control of the motor 102 is stopped when it is determined that serial communication is not normally performed. Was. As a result, although unexpected behavior of the motor 102 can be avoided, there is a problem that the reliability of motor drive control is impaired. When this motor control device is used, for example, in an electric power steering device, the stopping performance of the motor 102 significantly reduces the steering performance.
[0012]
(Second conventional technology)
On the other hand, the conventional motor control device in which data communication between two MPUs is performed by parallel communication has the following problems. That is, the distributed motor control device used in the electric power steering device tends to be miniaturized, and accordingly, various kinds of noises such as switching noise are included in the signal due to interference between the signal system and the power system. Are easily superimposed. When the motor command value calculated by the first MPU 101 is transmitted to the second MPU 103 via the 8-bit parallel communication line 105, data is latched by the parallel port 103b of the second MPU 103 at a timing when noise occurs. Then, the second MPU 103 erroneously recognizes “0” as “1” or “1” as “0”. In other words, so-called garbled bits occur. As a result, the second MPU 103 cannot receive a correct motor command value.
[0013]
When the motor command value calculated by the first MPU 101 is, for example, “+100”, this is “01100100 (B)” when represented by a signed binary number. Here, the most significant bit is a sign bit indicating positive / negative (+,-), and the second and subsequent digits from the most significant are numerical bits indicating a numerical value. Incidentally, positive is indicated by “0” and negative is indicated by “1”. Each bit of the motor command value is sent to the second MPU 103 via eight data lines D0 to D7 of the parallel communication line 105, respectively.
[0014]
At the time of transmission of the motor command value, if any of the upper 2 bits (for example, the upper 4 bits “0110”) is garbled in any of the numerical bits after the second digit from the most significant bit, the second MPU 103 erroneously performs The drive of the motor 102 is controlled based on the recognized excessive motor command value.
[0015]
For example, when the motor command value calculated by the first MPU 101 is “+ 36 = 00100100 (B)” and the second digit from the highest digit is garbled, the second MPU 103 sets the motor command value to “01100100 (B)”. ". This is +100 in decimal notation, which is an excessive value compared to the original motor command value “+36”.
[0016]
As shown in FIG. 16, for example, when noise is superimposed on the signal of the most significant bit of the motor command value and latched by the second MPU 103 at this timing, the second MPU 103 converts the motor command value to 11100100 (B ). This is "-100" in decimal notation. That is, the second MPU 103 outputs a current command in the direction opposite to the original direction to the motor 102, and the motor 102 rotates in the reverse direction (rotates in the direction of the reverse assist) although the motor 102 is supposed to rotate in the normal direction.
[0017]
As described above, the higher-order bits have a larger number of digits, and thus have a greater effect on the behavior of the motor 102. If the upper bits of the motor command value are garbled, the motor 102 is driven based on the excessive motor command value or the reverse motor command value as described above, and the motor 102 Could be shown. As a result, there is a problem that the reliability of the motor drive control is impaired.
[0018]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a motor control device that can ensure the reliability of motor drive control.
[0019]
[Means for Solving the Problems]
The first aspect of the present invention provides a first MPU that calculates a motor command value, a second MPU that controls driving of a motor based on the motor command value calculated by the first MPU, and a first MPU. A serial communication line or a parallel communication line connecting between the first MPU and the second MPU, wherein the serial communication line or the parallel communication line is provided between the first MPU and the second MPU. An analog communication line is provided separately, and the second MPU controls the drive of the motor based on one of the motor command values sent by the serial communication line or the parallel communication line and the analog communication line, respectively. The gist is that you have done it.
[0020]
According to a second aspect of the present invention, in the motor control device according to the first aspect, the second MPU includes a determination unit that determines whether serial communication or parallel communication is normally performed, When the determination means determines that the serial communication or the parallel communication is being performed normally, the second MPU controls the drive of the motor based on the motor command value sent by the serial communication or the parallel communication. When the means determines that serial communication or parallel communication is not normally performed, the second MPU controls the drive of the motor based on the motor command value sent by the analog communication line. And
[0021]
According to a third aspect of the present invention, in the motor control device according to the first or second aspect, a low-pass filter is provided in the middle of the analog communication line.
[0022]
According to a fourth aspect of the present invention, in the motor control device according to any one of the first to third aspects, the motor command value is a motor current command value, a motor angular velocity command value, and a motor angle command value. It shall be at least one of
[0023]
(Action)
According to the first aspect of the invention, the motor command value calculated by the first MPU is sent to the second MPU by a serial communication line or a parallel communication line and by analog. Then, the second MPU controls the drive of the motor based on one of the motor command values sent via the serial communication line, the parallel communication line, and the analog communication line. Therefore, even if a communication error occurs in one of serial communication, parallel communication, and analog communication, the second MPU can obtain a motor command value through another normal communication line.
[0024]
According to the second aspect of the present invention, in addition to the operation of the first aspect, when it is determined that the serial communication line or the parallel communication line is normally performed, the second MPU operates the serial MPU. The drive of the motor is controlled based on the motor command value sent by the communication line or the parallel communication line. When it is determined that the serial communication line or the parallel communication line is not normally performed, the second MPU controls the driving of the motor based on the motor command value sent by the analog communication line.
[0025]
According to the third aspect of the present invention, in addition to the operation of the first or second aspect, the motor command value sent by the analog communication line passes through a low-pass filter to reduce noise. The components are removed.
[0026]
According to the invention described in claim 4, in addition to the effect of the invention described in any one of claims 1 to 3, the second MPU includes a motor current command value, a motor angular speed command value, The drive of the motor is controlled based on at least one of the motor angle command values.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
(First Embodiment; EPS; Serial Communication Main)
Hereinafter, a first embodiment in which the present invention is embodied in a motor control device of an electric power steering device will be described with reference to FIGS.
[0028]
(overall structure)
As shown in FIG. 1, an electric power steering device (EPS) 1 includes an electric power steering control device (hereinafter, referred to as “control device 2”) and an electric motor 3 that is driven and controlled by the control device 2. A gear 4 is fixed to an output shaft of the electric motor 3. The electric motor 3 is a brushless motor composed of a three-phase synchronous permanent magnet motor, and includes a motor rotation angle sensor (for example, a Hall element) 5. The motor rotation angle sensor 5 detects the rotation angle θm of the electric motor 3, that is, an electrical angle indicating the position of the magnetic pole of the rotor constituting the electric motor 3, and sends the detection result (motor rotation angle signal) to the control device 2.
[0029]
On the other hand, a steering shaft 8 is connected to a steering wheel (hereinafter, referred to as a “handle 7”), and a reduction gear 9 is fixed to the steering shaft 8. The gear 4 of the electric motor 3 meshes with the reduction gear 9. A torsion bar (torsion spring) 10 is incorporated in the steering shaft 8, and the torsion bar 10 is provided with a torque sensor 11. The torque sensor 11 detects the steering torque T acting on the steering wheel 7 based on the amount of twist of the torsion bar 10 when the steering wheel 8 is rotated by the steering of the steering wheel 7 by the driver. This steering torque signal is sent to the control device 2.
[0030]
A pinion gear 13 is fixed to the reduction gear 9 via a pinion shaft 12. The pinion gear 13 meshes with a rack 14, and tie rods 15 are fixed to both ends of the rack 14. A knuckle arm 16 is rotatably connected to the tip of the tie rod 15, and a cross member 17 is rotatably connected between the knuckle arms 16, 16. A front wheel 18 is attached to each of the knuckle arms 16,16.
[0031]
Each of the front, rear, left and right wheels is provided with a vehicle speed sensor 19 (in FIG. 1, only the vehicle speed sensor 19 of one front wheel 18 is shown). The vehicle speed sensor 19 detects the wheel speed (the number of rotations of the wheel per unit time, that is, the rotation speed), and sends the detection result (wheel speed signal) to the control device 2. The control device 2 calculates the vehicle speed V based on the wheel speed signal sent from the vehicle speed sensor 19.
[0032]
When the driver rotates the steering wheel 7, the steering shaft 8 rotates. This rotation is transmitted to the rack 14 via the torsion bar 10, the pinion shaft 12, and the pinion gear 13, and is converted into the axial movement of the rack 14. As a result, both front wheels 18, 18 are steered.
[0033]
At this time, the control device 2 controls the electric motor 3 to generate a predetermined steering assist torque (assist torque) based on the steering torque T detected by the torque sensor 11 and the vehicle speed V detected by the vehicle speed sensor 19. Controls forward / reverse drive. The rotation of the electric motor 3 is transmitted to the reduction gear 9 via the gear 4, and the rotation speed is reduced by the reduction gear 9 and transmitted to the pinion shaft 12 and the pinion gear 13. The rotation of the pinion gear 13 is transmitted to the rack 14 and is converted into the axial movement of the rack 14. In this way, assist torque is applied to the steering of the front wheel 18 by the turning operation of the handle 7.
[0034]
(Control device)
Next, the electrical configuration of the control device 2 will be described.
As shown in FIG. 1, the control device 2 includes a first MPU (Micro Processing Unit) 21, a second MPU 22, a first ROM (read only memory) 23, a first RAM (read only memory) 24. , A second ROM 25, a second RAM 26, and a motor driving device 27. Further, the control device 2 includes a current sensor 28.
[0035]
The first ROM 23 stores various control programs such as a basic assist control program and a handle return control program executed by the first MPU 21, various data, various characteristic maps, and the like. The various characteristic maps are obtained in advance by experimental data based on a vehicle model and well-known theoretical calculations. For example, a basic assist torque map and a vehicle speed for obtaining a basic assist current based on the vehicle speed V and the steering torque T are provided. There is a map for obtaining the steering wheel return command current based on the steering angular velocity and the steering absolute angle.
[0036]
The first RAM 24 is a data work area in which various control programs written in the first ROM 23 are developed and the first MPU 21 executes various arithmetic processes. In addition, the first RAM 24 temporarily stores various calculation processing results when the first MPU 21 performs various calculation processing.
[0037]
The torque sensor 11 and the vehicle speed sensor 19 are connected to the first MPU 21 via input / output interfaces (not shown), respectively. The first MPU 21 executes various control programs such as a basic assist control program and a steering wheel return control program based on various information obtained from the torque sensor 11, the vehicle speed sensor 19, and the motor rotation angle sensor 5.
[0038]
The second ROM 25 stores various control programs such as a current control program and a PWM operation program executed by the second MPU 22 and various data.
[0039]
The second RAM 26 is a data work area in which various control programs written in the second MPU 22 are developed and the second MPU 22 executes various arithmetic processes. In addition, the second RAM 26 temporarily stores various calculation processing results when the second MPU 22 performs various calculation processing.
[0040]
The motor rotation angle sensor 5 and the current sensor 28 are connected to the second MPU 22 via input / output interfaces (not shown). The second MPU 22 executes various control programs such as a current control program and a PWM calculation program based on the calculation results of the first MPU 21 and various information obtained from the motor rotation angle sensor 5 and the current sensor 28.
[0041]
(Motor drive)
As shown in FIG. 2, the motor driving device 27 is configured such that a series circuit of FETs (field effect transistors) 31U and 32U, a series circuit of FETs 31V and 32V, and a series circuit of FETs 31W and 32W are connected in parallel. It is configured. A connection point 33U between the FETs 31U and 32U is connected to a U-phase winding of the electric motor 3, a connection point 33V between the FETs 31V and 32V is connected to a V-phase winding of the electric motor 3, and a connection point 33W between the FETs 31W and 32W. Is connected to the W-phase winding of the electric motor 3.
[0042]
A booster circuit (not shown) is provided on a power supply line Lp between the motor drive device 27 and a battery 34 mounted on the vehicle, and the booster circuit provides a command signal (boost circuit control) from the second MPU 22. The voltage of the battery 34 is boosted based on the signal) and applied to each series circuit of the motor driving device 27.
[0043]
As shown in FIG. 2, current sensors 28 are u-phase current sensors 28 u, v-phase current sensors 28 v and w which respectively detect three-phase excitation currents Iu, Iv, and Iw output from motor drive device 27 to electric motor 3. A phase current sensor 28w is provided. The u-phase current sensor 28u, the v-phase current sensor 28v, and the w-phase current sensor 28w send the detected u-phase excitation current Iu, v-phase excitation current Iv, and w-phase excitation current Iw to the second MPU 22, respectively.
[0044]
(Connection between the first and second MPUs)
As shown in FIG. 2, the first MPU 21 and the second MPU 22 are connected by a serial communication line Lc1 and an analog communication line Lc2, respectively. The serial communication line Lc1 is a main (main) communication line, and the analog communication line Lc2 is a sub (sub) communication line.
[0045]
The first MPU 21 has a D / A converter 41, and the second MPU 22 has an A / D converter 42. The D / A converter 41 and the A / D converter 42 are connected by an analog communication line Lc2. The D / A converter 41 converts the motor command value calculated by the first MPU 21 from a digital signal to an analog signal. The A / D converter 42 converts an analog signal sent by the analog communication line Lc2 into a digital signal.
[0046]
A low-pass filter 45 is provided in the middle of the analog communication line Lc2. The analog signal transmitted by the analog communication line Lc2 passes through the low-pass filter 45 to remove its noise component. However, the degree of the noise component of the analog signal removed by the low-pass filter 45 depends on the resolution of the D / A converter 41 and the A / D converter 42.
[0047]
The first MPU 21 calculates a basic assist current value corresponding to the vehicle speed V and the steering torque T based on the basic assist torque map, and outputs the calculation result (that is, the motor command value) to the serial communication line Lc1 and the analog communication The signal is sent to the second MPU 22 via the line Lc2.
[0048]
The second MPU 22 detects the u-phase excitation current detected by the u-phase current sensor 28u, the v-phase current sensor 28v, and the w-phase current sensor 28w based on the rotation angle θm of the electric motor 3 detected by the motor rotation angle sensor 5. The d-axis and q-axis currents are obtained by dq conversion of Iu, v-phase excitation current Iv and w-phase excitation current Iw. Then, the second MPU 22 calculates a PI control value based on the basic assist current value sent from the first MPU 21 and the q-axis current.
[0049]
The second MPU 22 performs a PWM operation according to the PI control value, and outputs the result of the PWM operation (motor control signal) to the motor driving device 27, specifically, FETs 31U and 32U, FETs 31V and 32V, FETs 31W and 32W. Is output for each. The motor drive device 27 supplies the basic assist current (three-phase excitation current) to the electric motor 3 via the three-phase excitation current path based on the result of the PWM calculation sent. The electric motor 3 applies a basic assist force to the steering wheel 7 based on the supply of the basic assist current.
[0050]
(Operation of the embodiment)
Next, the operation of the electric power steering control device configured as described above will be described with reference to the flowcharts shown in FIGS. The flowchart shown in FIG. 5A is executed according to various control programs stored in the first ROM 23 in advance. The flowchart shown in FIG. 5B is executed according to various control programs stored in the second ROM 25 in advance. In this embodiment, “step” is abbreviated as “S”.
[0051]
(Operation of the first MPU)
As shown in FIG. 5A, the first MPU 21 first reads a sensor signal, that is, a steering torque T detected by the torque sensor 11 and a vehicle speed V detected by the vehicle speed sensor 19 (S101). Then, the first MPU 21 calculates an m-bit (8-bit in this embodiment) motor command value (assist command current value) based on the steering torque T and the vehicle speed V (S102).
[0052]
Next, the first MPU 21 transmits the motor command value serially one bit at a time to the second MPU 22 via the serial communication line Lc1 (the motor command value S1 shown in FIG. 2) (S103). Further, the first MPU 21 converts the motor command value into an analog signal by the D / A converter 41 and transmits the analog signal to the second MPU 22 via the analog communication line Lc2 (motor command value S2 shown in FIG. 2). (S104).
[0053]
After that, the first MPU 21 repeats the processing of S101 to S104 every predetermined control cycle.
(Operation of the second MPU)
On the other hand, in the second MPU 22, the following processing is performed. That is, as shown in FIG. 3B, the second MPU 22 first determines whether serial communication is normally performed (S201). For example, the second MPU 22 determines whether the serial communication is normal based on the presence or absence of a timeout error or an overrun error. If the next data (bit) is not sent within a predetermined time, the second MPU 22 determines that a time-out error has occurred. If the next data is sent while the data is being received, the second MPU 22 determines that an overrun error has occurred.
[0054]
In S201, an error may be detected by a checksum (check sum). In this case, the first MPU 21 calculates the total value (check sum) of the motor command value (8-bit data), attaches this, and sends the data. Then, the second MPU 22 similarly calculates a checksum from the transmitted data string, and checks whether or not the checksum matches the checksum transmitted from the first MPU 21. If the two are different, the second MPU 22 determines that an error has occurred in the data on the communication path.
[0055]
Then, when it is determined that the serial communication is normally performed (YES in S201), the second MPU 22 receives the motor command value S1 sent by the serial communication line Lc1 (S202), and The driving of the electric motor 3 is controlled based on S1 (S203).
[0056]
On the other hand, when it is determined that serial communication is not normally performed (NO in S201), the second MPU 22 converts the motor command value S2 sent via the analog communication line Lc2 into a digital signal by the A / D converter 42. The electric motor 3 is converted and received (S204), and the electric motor 3 is drive-controlled based on the motor command value S2 (S205). Although the accuracy of the motor command value S2 depends on the resolution of the D / A converter 41 and the A / D converter 42, the accuracy may be reduced so that the electric motor 3 exhibits unexpected behavior (for example, reverse rotation). There is no.
[0057]
As described above, even if an abnormality occurs in the serial communication, the provisional motor control is performed based on the motor command value S2 sent through the backup analog communication line Lc2, thereby improving the reliability of the motor drive control. Thus, the steering performance of the electric power steering device 1 is ensured. When the drive control of the electric motor 3 is stopped, the steering assist by the electric motor 3 is not performed at all, so that the steering performance is significantly deteriorated.
[0058]
The step S201 constitutes a judging means for judging whether or not the serial communication is normally performed.
(Effects of the embodiment)
Therefore, according to the present embodiment, the following effects can be obtained.
[0059]
(1) An analog communication line Lc2 is provided separately from the serial communication line Lc1. Then, the second MPU 22 controls the drive of the electric motor 3 based on one of the motor command values sent via the serial communication line Lc1 and the analog communication line Lc2. That is, the second MPU 22 determines whether or not the serial communication is normally performed. If the second MPU 22 determines that the serial communication is normally performed, the second MPU 22 determines whether or not the motor command value S1 transmitted through the serial communication line Lc1 is correct. The drive of the electric motor 3 is controlled based on this. When it is determined that the serial communication is not normally performed, the second MPU 22 controls the drive of the electric motor 3 based on the motor command value S2 sent via the analog communication line Lc2. For this reason, even when serial communication between the first MPU and the second MPU is not performed normally, the drive control of the electric motor 3 is continued based on the motor command value S2 from the analog communication. be able to. Therefore, the reliability of the motor drive control can be ensured. As a result, the reliability of the electric power steering device 1 can be ensured.
[0060]
(2) The low-pass filter 45 is provided in the middle of the analog communication line Lc2. For this reason, the motor command value S2 sent by the analog communication line Lc2 passes through the low-pass filter 45 to remove its noise component. Therefore, erroneous data recognition of the motor command value S2 in the second MPU 22 (such as a bit error caused by noise during communication) is suppressed. As a result, the drive of the electric motor 3 can be controlled based on the motor command value closer to the original motor command value S1.
[0061]
(3) A motor current command value (specifically, a basic assist current value) is used as the motor command value. Therefore, the control device 2 can be applied to a system that controls the current of the motor.
[0062]
(Second Embodiment; EPS; Parallel Communication Main)
Next, a second embodiment of the present invention will be described. This embodiment is different from the first embodiment in that the main communication line is a parallel communication line. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.
[0063]
As shown in FIG. 4, the first MPU 21 and the second MPU 22 are connected by a parallel communication line Lc3 and an analog communication line Lc2, respectively. The parallel communication line Lc3 is a main (main) communication line, and the analog communication line Lc2 is a sub (sub) communication line.
[0064]
The parallel communication line Lc3 has the same number of data lines as the bit length of the motor command value sent from the first MPU 21 to the second MPU 22. In the present embodiment, since the bit length of the motor command value is set to 8 bits, the parallel communication line Lc3 includes eight data lines D0 to D7.
[0065]
The first MPU 21 has a parallel port 43, and the second MPU 22 has a parallel port 44. Both parallel ports 43 and 44 are 8-bit parallel ports at bit positions b0 to b7, respectively. Data lines D0 to D7 are connected between the parallel port 43 of the first MPU 21 and the parallel port 44 of the second MPU 22, specifically, between the bit positions b0 to b7 of the two parallel ports 43 and 44, respectively. .
[0066]
The first MPU 21 sends the calculated motor command value to the second MPU 22 via the parallel communication line Lc3 and the analog communication line Lc2. The second MPU 22 controls the drive of the electric motor 3 based on the motor command value and the like sent from the first MPU 21.
[0067]
(Operation of the embodiment)
Next, the operation of the electric power steering control device configured as described above will be described with reference to the flowcharts shown in FIGS. The flowchart shown in FIG. 3A is executed according to various control programs stored in the first ROM 23 in advance. The flowchart shown in FIG. 3B is executed according to various control programs stored in the second ROM 25 in advance.
[0068]
(Operation of the first MPU)
As shown in FIG. 3A, the first MPU 21 first reads a sensor signal, that is, the steering torque T detected by the torque sensor 11 and the vehicle speed V detected by the vehicle speed sensor 19 (S301).
[0069]
Next, the first MPU 21 calculates a motor command value (assist command current value) based on the steering torque T and the vehicle speed V (S302).
In the present embodiment, the motor command value is 8-bit data. For example, when the motor command value is “+100”, it is “01100100 (B)” when represented by a signed binary number. (B) is a symbol indicating that it is a binary number. The most significant bit (“0” in this embodiment) is a sign bit, and indicates whether the motor command value is positive or negative, that is, “+” or “−”. When the sign bit is “0”, it indicates “+”, and when it is “1”, it indicates “−”. The second and subsequent digits from the highest order are numerical bits indicating a numerical value.
[0070]
Next, the first MPU 21 sets all bits (8 bits) of the calculated motor command value in the parallel port 43 (S303). At this time, the bit positions b0 to b7 of the parallel port 43 correspond to the bit positions b0 to b7 of the motor command value so that the bit positions b0 to b7 of the parallel port 43 correspond to 0, 1, 1, 0, 0, 0, respectively. 1,0,0 is set. Then, the first MPU 21 sends the data set in the parallel port 43 to the second MPU 22 via the parallel communication line Lc3.
[0071]
Further, the first MPU 21 converts the motor command value into an analog amount by the D / A converter 41, and transmits this analog signal to the second MPU 22 via the analog communication line Lc2 (motor command value S2 shown in FIG. 2). (S304).
[0072]
After that, the first MPU 21 repeats the processing of S301 to S304 every predetermined control cycle.
(Operation of the second MPU)
On the other hand, in the second MPU 22, the following processing is performed. That is, as shown in FIG. 5B, the second MPU 22 first latches (holds) the motor command value S1 sent from the first MPU 21 via the parallel communication line Lc3 to the parallel port 44 and receives it. (S401). In the present embodiment, 0, 1, 1, 0, 0, 1, 0, 0 are held in bit positions b0 to b7 of the parallel port 44, respectively.
[0073]
Further, the second MPU 22 converts the motor command value S2 sent by the analog communication line Lc2 into a digital signal by the A / D converter 42 and receives it (S402).
Next, the second MPU 22 determines whether the parallel communication is normally performed (S403). For example, the second MPU 22 receives the motor command value S1 twice in a time-division manner, and calculates an exclusive OR (exclusive OR) of these two data for each bit. This operation is a process of two inputs and one output. When only one of the inputs is “1”, the output is “1”. In other words, when the inputs are both “1” or both are “0”, the output is “0”. Therefore, if the comparison result for each bit of the two data is “0”, there is no garbled bit, and the second MPU 22 determines that the data communication has been performed normally. Conversely, if the comparison result for each bit in the two data is “1”, the second MPU 22 determines that the bits are garbled.
[0074]
In S403, garbled bits (bit errors) may be detected by a parity check or the like. In this case, the first MPU 21 attaches 1 (or 0) even-odd (parity bits) included in the motor command value (8-bit data) to transfer the data. Then, the second MPU 22 compares the attached parity bit with the number of 1s (or 0s) included in the data, and determines that there is an error in the data if the oddness does not match.
[0075]
When judging that the parallel communication is performed normally (YES in S403), the second MPU 22 controls the drive of the electric motor 3 based on the motor command value S1 sent by the parallel communication line Lc3 (S404). . On the other hand, when it is determined that the parallel communication is not performed normally (NO in S403), the second MPU 22 controls the drive of the electric motor 3 based on the motor command value S2 sent via the analog communication line Lc2 ( S405).
[0076]
Thereafter, the second MPU 22 repeats the processing of S401 to S405 every predetermined control cycle. Note that S403 constitutes a judging means for judging whether or not the parallel communication is normally performed.
[0077]
Therefore, according to the present embodiment, the following effects can be obtained.
-When there is an abnormality in the parallel communication, provisional motor control is performed based on the motor command value S2 sent via the backup analog communication line Lc2. Therefore, the electric motor 3 is not driven by an incorrect motor command value (a motor command value having a bit error). Further, even when a bit error is detected in the motor command value transmitted by the parallel communication line Lc3, the electric motor 3 is continuously driven and controlled based on the motor command value S2 transmitted by the analog communication line Lc2. You. Therefore, unlike the case where the drive control of the electric motor 3 is stopped when an error is detected, the reliability of the motor drive control can be ensured. As a result, the reliability and the steering performance of the electric power steering device 1 can be ensured.
[0078]
(Third embodiment; VGRS; parallel communication main)
Next, a third embodiment in which the present invention is embodied in a variable gear ratio steering system will be described. This embodiment is different from the second embodiment in that the control target is not the electric motor of the electric power steering device but the electric motor of the variable gear ratio steering system. Therefore, the same components as those in the second embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.
[0079]
As shown in FIG. 6, one end of a first steering shaft 53 is connected to a steering wheel (hereinafter, referred to as a handle 52) of a variable gear ratio steering system (VGRS) 51. The other end is connected to the input side of the variable gear ratio unit 54. One end of a second steering shaft 55 is connected to the output side of the variable gear ratio unit 54, and the other end of the second steering shaft 55 is connected to the input side of a steering gear box 56. The steering gear box 56 includes a pinion gear (not shown), and the pinion gear meshes with a rack shaft 57. The rotational motion input to the second steering shaft 55 is transmitted to the rack shaft 57 via the pinion gear, and is converted into the axial motion of the rack shaft 57.
[0080]
The variable gear ratio unit 54 includes a speed reducer 58 that operatively connects the first steering shaft 53 and the second steering shaft 55, and an electric motor 59 that drives the speed reducer 58. By the driving of the electric motor 59, the transmission ratio (steering gear ratio) between the first steering shaft 53 and the second steering shaft 55 changes via the speed reducer 58. Incidentally, in the case of the rack and pinion type electric power steering device 1 in the present embodiment, the steering gear ratio is a ratio between the total rotation angle (from lock to lock) of the handle 7 and the turning angle of the wheel (steered wheel). Say.
[0081]
As shown in FIG. 7, the variable gear ratio steering system 51 includes a steering angle sensor 61 for detecting a rotation angle of the first steering shaft 53 (ie, the steering angle θh) and a rotation angle (ie, output) of the second steering shaft 55. An output angle sensor 62 for detecting the angle θp) is provided. The variable gear ratio steering system 51 includes a vehicle speed sensor 63 for detecting a vehicle speed V and a rotation angle sensor 64 for detecting a rotation angle (electric angle) of the electric motor 59.
[0082]
The steering angle θh detected by the steering angle sensor 61, the output angle θp detected by the output angle sensor 62, the vehicle speed V detected by the vehicle speed sensor 63, and the rotation angle θm of the electric motor 59 detected by the rotation angle sensor 64 are: Each is sent to the control device 65 of the variable gear ratio steering system 51. The control device 65 controls the driving of the electric motor 59 based on the steering angle θh, the output angle θp, the vehicle speed V, and the rotation angle θm.
[0083]
That is, the first MPU 21 of the control device 65 refers to the motor rotation angle characteristic map (not shown) stored in advance in the first ROM 23 (see FIG. 1) based on the steering angle θh and the vehicle speed V to change the gear. A motor rotation angle command value (motor angle command value) of the electric motor 59 in the ratio variable unit 54 is calculated. The motor rotation angle characteristic map shows a change in the motor rotation angle command value with an increase in the vehicle speed V, and the motor rotation angle command value is uniquely determined according to the vehicle speed V.
[0084]
The first MPU 21 sends all bits (8 bits) of the calculated motor rotation angle command value to the second MPU 22 via the parallel communication line Lc3. Further, the second MPU 22 converts the motor rotation angle command value into an analog signal by the D / A converter 41 and sends the motor rotation angle command value to the second MPU 22 via the analog communication line Lc2 (FIG. 5 (a)). See the flowchart in FIG.
[0085]
The second MPU 22 determines whether or not the parallel communication is normal. When the second MPU 22 determines that the parallel communication is normal, the second MPU 22 uses the electric motor 59 based on the motor rotation angle command value transmitted through the parallel communication line Lc3. (See the flowchart of FIG. 5B).
[0086]
At this time, the rotation angle θm of the electric motor 59 detected by the rotation angle sensor 64 is returned to the second MPU 22. Then, the second MPU 22 performs feedback control on the motor current so that the motor rotation angle command value calculated by the first MPU 21 matches the actual rotation angle θm of the electric motor 59.
[0087]
By setting the transmission ratio (steering gear ratio) according to the vehicle speed V, the steering performance of the steering wheel 7 is improved. For example, when the vehicle is stopped or running at low speed, the steering gear ratio is set such that the output angle θp of the variable gear ratio unit 54 becomes larger than the steering angle θh of the steering wheel 7. As a result, it is possible to turn with less steering operation. Further, the steering gear ratio is set such that the output angle θp of the variable gear ratio unit 54 becomes smaller than the steering angle θh of the steering wheel 7 during high-speed running. As a result, a gentle and stable vehicle response is realized.
[0088]
On the other hand, when it is determined that the parallel communication is abnormal, the second MPU 22 controls the drive of the electric motor 59 based on the motor rotation angle command value transmitted via the analog communication line Lc2. Note that the A / D converter 42 converts the motor rotation angle command value sent via the analog communication line Lc2 into an analog signal at the time of reception thereof (see the flowchart of FIG. 5B).
[0089]
Therefore, according to the present embodiment, in a system in which the motor angle command value (specifically, the motor rotation angle command value) is used as the motor command value, the same effect as in the second embodiment can be obtained. Can be. Further, the control device 65 can be applied to another system for controlling the angle of the motor (position control).
[0090]
(Fourth embodiment; NC machine tool; parallel communication main)
Next, a fourth embodiment in which the present invention is embodied in an NC machine tool will be described. This embodiment is different from the second embodiment in that the control target is not the electric motor of the electric power steering device but the table feed electric motor of the NC machine tool. Therefore, the same components as those in the second embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.
[0091]
As shown in FIG. 8, a ball screw 73 is rotatably supported on a fixed table 72 of an NC machine tool 71 via a bearing (not shown). An outer end of the ball screw 73 is connected to an electric motor for feeding. 74 is connected to the output shaft via a coupling (not shown). A nut 75 is screwed into the ball screw 73. The nut 75 can be advanced and retracted with the forward and reverse rotation of the ball screw 73. A headstock 77 is provided on an upper surface of the nut 75 via a moving table 76 so as to be integrally movable. A spindle motor 78 is fixed to the headstock 77, and a spindle 79 is operatively connected to an output shaft of the spindle motor 78. A tool 80 such as a tap is attached to the tip of the main shaft 79.
[0092]
Therefore, when the feed electric motor 74 is driven, the rotation of the ball screw 73 causes the nut 75 to reciprocate along the ball screw 73, and accordingly, the moving table 76 also moves in the direction along the axis of the ball screw 73 ( (In the direction of the arrow shown in FIG. 8). When the spindle motor 78 is driven, the tool 80 rotates forward and backward together with the spindle 79.
[0093]
The NC machine tool 71 includes a feed motor rotation angle sensor 81 that detects the rotation angle θms of the feed electric motor 74, and a spindle motor rotation angle sensor 82 that detects the rotation angle θmp of the spindle motor 78. The rotation angle θms and the rotation angle θmp detected by the feed motor rotation angle sensor 81 and the main shaft motor rotation angle sensor 82 are sent to the control device 91 of the NC machine tool 71, respectively.
[0094]
As shown in FIG. 9, the control device 91 includes a first MPU 21, a second MPU 22, a feed motor drive device 92, a spindle motor drive device 93, and a PLO (programmable logic control device) 94. This PLO 94 is connected to the first MPU 21. An input / output device (operation panel) 95 is connected to the PLO 94. The PLO 94 has a sequencer function, determines and selects an NC program to be executed by the first MPU 21, and causes the first MPU 21 to execute the NC program according to a predetermined program command.
[0095]
That is, the first MPU 21 controls the motor command value (motor angle command value; feed amount of the moving table 76) for the feed electric motor 74 and the spindle motor based on a predetermined program command from the PLO 94 at each predetermined control cycle. The motor command value for 78 (motor angular speed command value; rotational angular speed of the main shaft 79) is calculated.
[0096]
The first MPU 21 sends all bits of the calculated motor angle command value and all bits of the motor angular velocity command value to the second MPU 22 via the parallel communication line Lc3. Further, the second MPU 22 converts the motor angle command value and the motor angular speed command value into analog signals by the D / A converter 41, and converts the motor angle command value and the motor angular speed command value into the second signal via the analog communication line Lc2. It is sent to the MPU 22 (see the flowchart of FIG. 5A).
[0097]
The second MPU 22 determines whether or not the parallel communication is normal. If the second MPU 22 determines that the parallel communication is normal, the second MPU 22 determines whether the parallel communication is normal, based on the motor angle command value and the motor angular speed command value sent by the parallel communication line Lc3. The drive of the motor 74 and the spindle motor 78 are controlled (see the flowchart of FIG. 5B).
[0098]
At this time, the rotation angle θms detected by the feed motor rotation angle sensor 81 and the rotation angle θmp detected by the main shaft motor rotation angle sensor 82 are respectively fed back to the second MPU 22. The second MPU 22 feedback-controls the motor currents of the feed electric motor 74 and the spindle motor 78 based on the rotation angles θms and θmp. That is, the second MPU 22 controls the feed electric motor 74 and the main shaft so that the motor command values (motor angle command value and motor angular velocity command value) and the actual motor rotation angles (electrical angles) θms and θmp respectively match. Drive motors 78 are respectively controlled.
[0099]
On the other hand, when the second MPU 22 determines that the parallel communication is abnormal, the second MPU 22 controls the feed electric motor 74 and the main shaft motor 78 based on the motor angle command value and the motor angular speed command value sent by the analog communication line Lc2. Drive control is performed for each. Note that the motor angle command value and the motor angular speed command value sent via the analog communication line Lc2 are converted into analog signals by the A / D converter 42 when they are received (see the flowchart in FIG. 5B).
[0100]
Therefore, according to the present embodiment, in a system in which the motor angle command value and the motor angular velocity command value are used as the motor command value, the same effects as in the second embodiment can be obtained. Further, the control device 91 can be applied to another system for controlling the speed of the motor (angular speed control).
[0101]
(Fifth embodiment; VGRS; serial communication main)
Next, a fifth embodiment of the present invention will be described. This embodiment is different from the third embodiment in that the parallel communication line Lc3 is replaced with a serial communication line Lc1. Therefore, the same components as those of the third embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.
[0102]
As shown in FIG. 10, the first MPU 21 transmits all bits (8 bits) of the data constituting the calculated motor rotation angle command value to the second MPU 22 serially one bit at a time via the serial communication line Lc1. Further, the second MPU 22 converts the motor rotation angle command value into an analog signal by the D / A converter 41, and sends this motor rotation angle command value to the second MPU 22 via the analog communication line Lc2 (FIG. 3 (a)). )).
[0103]
The second MPU 22 determines whether serial communication is normally performed. When it is determined that the serial communication is normally performed, the second MPU 22 controls the drive of the electric motor 59 based on the data transmitted through the serial communication line Lc1, that is, the motor rotation angle command value. When determining that the serial communication is not performed normally, the second MPU 22 controls the drive of the electric motor 59 based on the motor rotation angle command value transmitted via the analog communication line Lc2. Note that the motor rotation angle command value sent via the analog communication line Lc2 is converted into an analog signal by the A / D converter 42 when the motor rotation angle command value is received (see the flowchart in FIG. 3B).
[0104]
Therefore, according to the present embodiment, in the system in which the motor angle command value (specifically, the motor rotation angle command value) is used as the motor command value, (1) and (2) in the first embodiment are used. ) The same effect as that of the second effect can be obtained. Further, the control device 65 can be applied to another system for controlling the angle of the motor similarly.
[0105]
(Sixth embodiment; NC machine tool)
Next, a sixth embodiment of the present invention will be described. This embodiment differs from the fourth embodiment in that the parallel communication line Lc3 is replaced with a serial communication line Lc1. Therefore, the same components as those of the fourth embodiment are denoted by the same reference numerals, and the duplicate description will be omitted.
[0106]
As shown in FIG. 11, the first MPU 21 converts all bits (8 bits) of the data constituting the calculated motor angle command value and the motor angular velocity command value into the second bit by bit in series by the serial communication line Lc1. The data is transmitted to the MPU 22. Further, the second MPU 22 converts the motor angle command value and the motor angular speed command value into analog signals by the D / A converter 41, and converts the motor angle command value and the motor angular speed command value into the second signal via the analog communication line Lc2. (See the flowchart of FIG. 3A).
[0107]
The second MPU 22 determines whether serial communication is normally performed. When it is determined that the serial communication is normally performed, the second MPU 22 sends the electric motor 74 for feeding and the spindle based on the data transmitted by the serial communication line Lc1, that is, the motor angle command value and the motor angular speed command value. Drive motors 78 are respectively controlled.
[0108]
When the second MPU 22 determines that the serial communication is not performed normally, the second MPU 22 sends the electric motor 74 for the feed and the motor 78 for the main shaft based on the motor angle command value and the motor angular speed command value sent by the analog communication line Lc2. Are respectively driven and controlled. The A / D converter 42 converts the motor angle command value and the motor angular speed command value sent via the analog communication line Lc2 into analog signals at the time of reception (see the flowchart in FIG. 3B).
[0109]
Therefore, according to the present embodiment, in a system in which the motor angle command value and the motor angular velocity command value are used as the motor command value, the same effects as (1) and (2) in the first embodiment are obtained. The effect can be obtained. Further, the control device 91 can be applied to another system for controlling the speed of the motor in the same manner.
[0110]
(Another example)
In the first to sixth embodiments, the first MPU 21 and the second MPU 22 are provided in the same control device 2, 65, 91, respectively. For example, the first MPU 21 is provided in the control device 2, 65, 91. May be provided outside. By doing so, the size of the control devices 2, 65, 91 can be reduced.
[0111]
In the first to third and fifth embodiments, the function of the first MPU 21 may be performed by an MPU of a system other than the electric power steering device 1 and the variable gear ratio steering system 51. For example, in a vehicle system in which the electric power steering device 1, the variable gear ratio steering system 51, and SC (stability control; stability control) are combined for integrated control, an integrated control ECU (IC) for integrated control of the vehicle system is provided. An electronic control unit) calculates a motor command value. Then, the calculation result is sent to the second MPU 22 by, for example, CAN (Controller Area Network) communication (ie, in-vehicle LAN). Motor current control is performed based on the calculation result (motor command value), and drive control of the electric motor 3 of the electric power steering device 1 and the electric motor 59 of the variable gear ratio steering system 51 is performed. By doing so, the size of the control devices 2 and 65 can be reduced.
[0112]
In the present embodiment, each of the first MPU 21 and the second MPU 22 is an 8-bit system, but may be a system having an arbitrary number of bits such as a 16-bit system.
[0113]
-Filtering means other than the low-pass filter 45 may be provided in the middle of the analog communication line Lc2. For example, the low-pass filter 45 is replaced with a band-pass filter.
[0114]
(Note)
Next, technical ideas that can be grasped from the embodiment and other examples will be additionally described below.
(A) A motor that is provided in a steering system of a vehicle so as to be capable of transmitting torque and generates a steering assist torque, a motor drive unit that drives the motor, and controls the drive of the motor by controlling the energization of the motor drive unit. An electric power steering device comprising a motor control device, the electric power steering device comprising the motor control device according to any one of claims 1 to 4.
[0115]
(B) A vehicle steering control device including a transmission ratio variable mechanism for changing a transmission ratio between a steering angle of a steering wheel and a steering angle of a steered wheel, wherein the steering detecting the steering angle of the steering wheel. An angle sensor, a vehicle speed sensor that detects a vehicle speed, an electric motor that drives the transmission ratio variable mechanism, and a steering angle that is set by the steering angle sensor while setting the transmission ratio based on the vehicle speed detected by the vehicle speed sensor. A variable gear ratio steering system comprising a motor control device according to any one of claims 1 to 4, the control system comprising: a control unit configured to drive and control the electric motor based on the control signal. .
[0116]
(C) In a data transmission method for transmitting data calculated by the first MPU to the second MPU via a serial communication line or a parallel communication line, the method comprises the steps of: An analog communication line is provided separately from the serial communication line or the parallel communication line. The second MPU determines whether the serial communication or the parallel communication is normal or not, and determines that the serial communication or the parallel communication is normal. The MPU receives the data sent by the serial communication line or the parallel communication line, and when it judges that the serial communication line or the parallel communication line is not normal, the second MPU transmits the data sent by the analog communication line. A data transmission method intended to be received.
[0117]
【The invention's effect】
According to the present invention, the second MPU drives and controls the motor based on one of the motor command values sent by the serial communication line or the parallel communication line and the analog communication line, respectively. The reliability of motor drive control can be ensured.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an electric power steering device according to a first embodiment.
FIG. 2 is a circuit diagram of a motor control device according to the first embodiment.
FIG. 3A is a flowchart illustrating a process of transmitting data by a first MPU according to the first embodiment;
FIG. 4B is a flowchart illustrating a process when the second MPU receives data in the first embodiment.
FIG. 4 is a circuit diagram of a motor control device according to a second embodiment.
FIG. 5A is a flowchart illustrating a process at the time of data transmission of a first MPU in the second embodiment;
9B is a flowchart illustrating a process performed by the second MPU when receiving data in the second embodiment.
FIG. 6 is a schematic configuration diagram of a variable gear ratio steering system according to a third embodiment.
FIG. 7 is a circuit diagram of a motor control device according to a third embodiment.
FIG. 8 is a schematic configuration diagram of an NC machine tool according to a fourth embodiment.
FIG. 9 is a circuit diagram of a motor control device according to a fourth embodiment.
FIG. 10 is a circuit diagram of a motor control device according to a fifth embodiment.
FIG. 11 is a circuit diagram of a motor control device according to a sixth embodiment.
FIG. 12 is a circuit diagram of a first conventional motor control device.
FIG. 13 (a) is a flowchart showing processing of the first conventional MPU when transmitting data,
(B) is a flowchart showing processing at the time of data reception of the first conventional second MPU.
FIG. 14 is a circuit diagram of a second conventional motor control device.
FIG. 15 (a) is a flowchart showing processing of the second conventional first MPU when transmitting data,
10B is a flowchart illustrating a process performed by the second conventional MPU when receiving data.
FIG. 16 is a timing chart showing the occurrence of garbled data.
[Explanation of symbols]
3,59,74,78 ... electric motor,
2, 65, 91: a control device constituting a motor control device;
21 ... First MPU,
22 ... the second MPU,
45 ... Low-pass filter,
D0 to D3: data lines of parallel communication lines,
Lc1 ... Serial communication line,
Lc2: analog communication line,
Lc3: parallel communication line,
S1, S2: Motor command values.

Claims (4)

A first MPU that calculates a motor command value, a second MPU that drives and controls a motor based on the motor command value calculated by the first MPU, and a first MPU and a second MPU. In a motor control device having a serial communication line or a parallel communication line to be connected,
An analog communication line is provided between the first MPU and the second MPU separately from the serial communication line or the parallel communication line,
A motor control device wherein the second MPU controls driving of a motor based on one of motor command values sent via a serial communication line, a parallel communication line, and an analog communication line. The second MPU includes a determination unit that determines whether serial communication or parallel communication is normally performed,
When it is determined that the serial communication or the parallel communication is normally performed by the determination unit, the second MPU drives and controls the motor based on the motor command value transmitted by the serial communication or the parallel communication,
When the determination means determines that serial communication or parallel communication is not normally performed, the second MPU drives and controls the motor based on the motor command value sent by the analog communication line. Item 2. The motor control device according to item 1. 3. The motor control device according to claim 1, wherein a low-pass filter is provided in the middle of the analog communication line. The motor control device according to any one of claims 1 to 3, wherein the motor command value is at least one of a motor current command value, a motor angular velocity command value, and a motor angle command value.

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