JP6566007B2 - Control device - Google Patents

Description

  The disclosure described in the present specification relates to a control device for a rotating electrical machine.

  As shown in Patent Document 1, a control device for a rotating electrical machine is known. The rotating electrical machine is provided with a rotation angle sensor. The rotation angle sensor detects the rotation angle of the rotor and outputs the detected value to the control device. The rotating electrical machine is provided with an induced voltage detector. The induced voltage detection unit detects an induced voltage generated in the armature winding of the stator and outputs the detected value to the control device.

JP 2017-28965 A

  When an abnormality occurs in the rotation angle sensor, the control device disclosed in Patent Document 1 detects the rotation angle of the rotating electrical machine based on a signal detected by the induced voltage detection unit. However, Patent Document 1 does not describe a specific configuration for detecting an abnormality of the rotation angle sensor (rotation angle sensor).

  Therefore, an object of the present disclosure is to provide a control device capable of detecting an abnormality of a rotation angle sensor.

One of the disclosures is a control device for a rotating electrical machine (200),
A rotation angle sensor (12) for detecting the rotation angle of the rotor (201) of the rotating electrical machine;
An induced voltage detector (13) for detecting an induced voltage of a stator coil (204 to 207) included in the stator (202) of the rotating electrical machine;
A calculation unit (15) for inputting the rotation angle detected by the rotation angle sensor and the induced voltage detected by the induced voltage detection unit;
The calculation unit determines a plurality of rise times and determination thresholds when the induced voltage detected by the induced voltage detection unit exceeds a predetermined comparison threshold when the stator inverter (30) that controls energization of the stator coil is stopped. Based on the difference between the rotation angles of the two rotors detected by the rotation angle sensor at each of the two detection times of the plurality of falling times when the time is below, and the phase interval of the induced voltage between the two detection times To determine the failure of the rotation angle sensor.

  When the rotor (201) rotates and thereby the magnetic field transmitted through the stator coils (204 to 207) changes, an induced voltage is generated in the stator coils (204 to 207). This induced voltage appears as a sine wave. For example, when the rotor (201) has eight magnetic pole pairs, eight cycles of sine waves appear while the rotor (201) makes one rotation at a mechanical angle.

  The phase of this induced voltage for one period is 45 ° in mechanical angle. Therefore, for example, the phase interval that rises again after the induced voltage of the sine waveform exceeds the comparison threshold value is 45 ° in mechanical angle. On the other hand, it is expected that the difference in rotation angle detected by the rotation angle sensor (12) when the induced voltage exceeds the comparison threshold value by 2 degrees is 45 ° in mechanical angle.

  Therefore, when the difference in rotation angle detected by the rotation angle sensor (12) is equal to the above phase interval, it can be determined that the rotation angle sensor (12) is normal. On the other hand, if the difference in the rotation angle detected by the rotation angle sensor (12) is different from the above phase interval, it can be determined that the rotation angle sensor (12) is abnormal.

  As described above, according to the present disclosure, a failure of the rotation angle sensor (12) can be determined. Further, according to the present disclosure, for example, an increase in the number of parts is suppressed as compared with a configuration in which a failure of the rotation angle sensor is determined based on detection results of a plurality of rotation angle sensors.

  Note that the reference numbers in parentheses above merely indicate the correspondence with the configurations described in the embodiments described later, and do not limit the technical scope in any way.

It is a circuit diagram which shows a motor and a motor control apparatus. It is a block diagram for demonstrating schematic structure of a failure detection part. It is a graph for demonstrating an induced voltage. It is a graph for demonstrating the failure detection of 1st Embodiment. It is a graph which shows the rotation angle detected by the rotation angle sensor at the time of failure. It is a flowchart which shows the failure detection flow of a failure detection part. It is a flowchart which shows the modification of a failure detection flow. It is a graph which shows the modification of failure detection. It is a graph shown for demonstrating the failure detection of 2nd Embodiment. It is a graph which shows the modification of failure detection.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
(First embodiment)
A motor control device 100 according to the present embodiment will be described with reference to FIGS. The motor control device 100 controls the motor 200 based on a request command from the host ECU. The motor control device 100 and the motor 200 constitute a so-called ISG. ISG is an abbreviation for Integrated Starter Generator. The motor control device 100 corresponds to the control device.

  The motor control device 100 and the motor 200 are integrated. That is, the motor control device 100 and the motor 200 have a so-called electromechanical integrated configuration. The motor control device 100 and the motor 200 are housed in an engine room.

  Motor 200 is connected to a crankshaft of engine 300 mounted on the vehicle via belt 310. Therefore, the motor 200 and the crankshaft rotate in conjunction with each other. When the motor 200 rotates autonomously, the rotation is transmitted to the crankshaft. As a result, the crankshaft rotates. The engine 300 is started or the vehicle is assisted. On the contrary, when the crankshaft rotates autonomously, the rotation is transmitted to the motor 200. As a result, the motor 200 rotates. Electricity generation of the motor 200 is performed.

<Configuration of motor>
As shown in FIG. 1, the motor 200 includes a rotor 201 and a stator 202. In addition, the motor 200 has a shaft and a pulley (not shown). The shaft is rotatably provided in the motor control device 100. A pulley is provided at the tip of the shaft. The belt 310 is connected to the pulley. Thereby, the rotation of the crankshaft is transmitted to the pulley via the belt 310. In other words, the rotation of the shaft is transmitted to the crankshaft via the belt 310. The motor 200 corresponds to a rotating electric machine.

  The rotor 201 has a rotor coil 203. Although not shown, the rotor 201 has a fixing portion for fixing the rotor coil 203 to the shaft. The fixed part has a cylindrical shape. The shaft is inserted and fixed in the hollow of the fixing portion. The rotor coil 203 is provided inside the fixed portion. The rotor coil 203 is electrically connected to the wiring provided on the shaft. This wiring is electrically connected to the slip ring of the shaft. The slip ring is formed in an annular shape around the shaft axis. A brush made of a conductive material is in contact with the annular slip ring. This brush is electrically connected to the motor control device 100. A current is supplied to the brush from the motor control device 100. This current is supplied to the rotor coil 203 via the brush, slip ring, and wiring. As a result, a magnetic field is generated in the rotor coil 203. The rotor coil 203 corresponds to a field winding.

  As described above, a magnetic field is generated from the rotor coil 203 by energization. This magnetic field passes through each of the rotor coil 203 and the fixing portion that fixes the rotor coil 203 to the shaft. Therefore, the rotor coil 203 and a part of the fixed part are magnetized. Therefore, even if the rotor coil 203 is not energized as described above, a magnetic field is output from the rotor 201 although it is weak. This weak magnetic field also passes through the stator coil 204.

  The stator 202 has a stator coil 204. Although not shown, the stator 202 has a stator core on which a stator coil 204 is provided. The stator core has a cylindrical shape. A rotor 201 is provided in the hollow of the stator core together with a shaft. Thus, the stator 202 is provided around the rotor 201. Stator coil 204 has U-phase stator coil 205, V-phase stator coil 206, and W-phase stator coil 207.

  Each of U-phase stator coil 205, V-phase stator coil 206, and W-phase stator coil 207 is integrally connected to motor control device 100 via a bus bar. Three-phase alternating current is supplied from the motor control device 100 to the U-phase stator coil 205, the V-phase stator coil 206, and the W-phase stator coil 207. The U-phase stator coil 205, the V-phase stator coil 206, and the W-phase stator coil 207 are supplied with alternating current whose phases are shifted from each other by 120 ° in electrical angle. As a result, a three-phase rotating magnetic field is generated from the U-phase stator coil 205, the V-phase stator coil 206, and the W-phase stator coil 207.

  When current flows through each of the rotor coil 203 and the stator coil 204, a magnetic field is generated from both. As a result, rotational torque is generated in the rotor coil 203. The direction in which the rotational torque is generated sequentially changes according to the phase change of the three-phase rotating magnetic field. As a result, the shaft rotates autonomously. The pulley rotates with the shaft. This rotation is transmitted to the crankshaft via the belt 310. As a result, the crankshaft also rotates.

  On the contrary, when the engine 300 is driven to burn and the crankshaft rotates autonomously, the rotation is transmitted to the pulley via the belt 310. When the crankshaft is rotated by the rotation of the wheel, the rotation is transmitted to the pulley via the belt 310. Thereby, the shaft rotates together with the pulley. As a result, the rotor coil 203 also rotates. The magnetic field generated by the rotor coil 203 intersects with the stator coil 204. As a result, an induced electromotive force is generated in the stator coil 204. As a result, a current flows through the stator coil 204. This current is supplied to the vehicle battery 400 via the motor control device 100.

<Configuration of motor control device>
As shown in FIG. 1, the motor control device 100 has a positive terminal 100 a and a negative terminal 100 b for electrical connection with the battery 400. The positive electrode terminal 100 a is connected to the positive electrode of the battery 400. Negative electrode terminal 100 b is connected to the negative electrode of battery 400. A smoothing capacitor 100c is connected between the positive terminal 100a and the negative terminal 100b.

  As shown in FIG. 1, the motor control device 100 includes a stator inverter 30 and a rotor inverter 50 that are connected in parallel between a positive electrode terminal 100a and a negative electrode terminal 100b. The motor control device 100 includes an ISGECU 10 that controls driving of the stator inverter 30 and the rotor inverter 50, and a current sensor 70 that detects currents of the stator inverter 30 and the rotor inverter 50.

  The ISGECU 10 is electrically connected to the stator inverter 30 and the rotor inverter 50, respectively. As will be described in detail later, the ISGECU 10 has a microcomputer 11. The microcomputer 11 can communicate with a host ECU or engine ECU mounted on the vehicle via a bus or the like. A request command is input to the microcomputer 11 from the host ECU. The microcomputer 11 generates a control signal for controlling the stator inverter 30 and the rotor inverter 50 based on the input request command and the detection signal of the current sensor 70 and the rotation angle sensor 12 described later. The microcomputer 11 outputs the control signal to a stator driver 17 and a rotor driver 18 which will be described later. Thus, drive signals are output from the stator driver 17 and the rotor driver 18 to the stator inverter 30 and the rotor inverter 50, respectively. As a result, the driving of the stator inverter 30 and the rotor inverter 50 is controlled.

  Stator inverter 30 has U-phase leg 31, V-phase leg 32, and W-phase leg 33 connected in parallel between positive electrode terminal 100a and negative electrode terminal 100b. Each of these three legs has a high-side switch element and a low-side switch element connected in series in order from the positive terminal 100a to the negative terminal 100b.

  Specifically, the U-phase leg 31 has a U-phase high-side switch element 34 and a U-phase low-side switch element 35. The V-phase leg 32 includes a V-phase high-side switch element 36 and a V-phase low-side switch element 37. The W-phase leg 33 includes a W-phase high-side switch element 38 and a W-phase low-side switch element 39.

  The switch element constituting the stator inverter 30 is a MOSFET. For this purpose, each of these switch elements has a parasitic diode. That is, the U-phase high-side switch element 34 has a U-phase high-side diode 34a. The U-phase low-side switch element 35 has a U-phase low-side diode 35a. The V-phase high-side switch element 36 has a V-phase high-side diode 36a. The V-phase low-side switch element 37 has a V-phase low-side diode 37a. The W-phase high-side switch element 38 has a W-phase high-side diode 38a. The W-phase low-side switch element 39 includes a W-phase low-side diode 39a. The cathode electrodes of these parasitic diodes are on the positive electrode terminal 100a side. The anode electrode is on the negative electrode terminal 100b side.

  As shown in FIG. 1, one end of each of U-phase stator coil 205, V-phase stator coil 206, and W-phase stator coil 207 is connected to each other. Thereby, the U-phase stator coil 205, the V-phase stator coil 206, and the W-phase stator coil 207 are Y-connected.

  The other end of the U-phase stator coil 205 is connected to the midpoint of the U-phase high-side switch element 34 and the U-phase low-side switch element 35. The other end of the V-phase stator coil 206 is connected to the midpoint of the V-phase high-side switch element 36 and the V-phase low-side switch element 37. The other end of the W-phase stator coil 207 is connected to the midpoint of the W-phase high-side switch element 38 and the W-phase low-side switch element 39.

  With the above electrical connection configuration, for example, when the U-phase high-side switch element 34, the V-phase low-side switch element 37, and the W-phase low-side switch element 39 are closed by the drive signal from the stator driver 17, the stator coil 204 is closed. Current flows through Specifically, a current flows from the positive terminal 100a to the negative terminal 100b through the U-phase high-side switch element 34, the U-phase stator coil 205, the V-phase stator coil 206, and the V-phase low-side switch element 37. . A current flows from the positive terminal 100 a to the negative terminal 100 b through the U-phase high-side switch element 34, the U-phase stator coil 205, the W-phase stator coil 207, and the W-phase low-side switch element 39.

  In the present embodiment, a module type power MOSFET is employed as a switch element constituting the stator inverter 30. Therefore, the current rating of each of the switch element and the parasitic diode is high, and the switch element and the parasitic diode are designed to withstand the current when the battery 400 is reversely connected. A so-called single-sided cooling system is employed for the switch elements constituting the stator inverter 30.

  The rotor inverter 50 has an E-phase leg 51 and an F-phase leg 52 connected in parallel between the positive terminal 100a and the negative terminal 100b. The E-phase leg 51 includes an E-phase high-side switch element 54 and an E-phase low-side switch element 55 that are connected in series from the positive terminal 100a to the negative terminal 100b. The F-phase leg 52 includes an F-phase high-side switch element 56 and an F-phase low-side switch element 57 that are connected in series from the positive terminal 100a to the negative terminal 100b. These four switch elements constitute a full bridge circuit.

  The switch element constituting the rotor inverter 50 described above is a MOSFET. Therefore, each switch element has a parasitic diode. That is, the E-phase high-side switch element 54 has an E-phase high-side diode 54a. The E-phase low-side switch element 55 has an E-phase low-side diode 55a. The F-phase high-side switch element 56 includes an F-phase high-side diode 56a. The F-phase low-side switch element 57 includes an F-phase low-side diode 57a. The cathode electrodes of these parasitic diodes are on the positive electrode terminal 100a side. The anode electrode is on the negative electrode terminal 100b side.

  The brushes are connected to the midpoints of the E-phase high-side switch element 54 and the E-phase low-side switch element 55, and the midpoints of the F-phase high-side switch element 56 and the F-phase low-side switch element 57, respectively. The brush contacts the slip ring of the shaft, and the slip ring is electrically connected to the rotor coil 203 via a wiring.

  As shown in FIG. 1, the midpoint of the E-phase high-side switch element 54 and the E-phase low-side switch element 55 is electrically connected to one end of the rotor coil 203. The midpoint of the F-phase high-side switch element 56 and the F-phase low-side switch element 57 is electrically connected to the other end of the rotor coil 203.

  With the above connection configuration, for example, when the E-phase high-side switch element 54 and the F-phase low-side switch element 57 are closed by the drive signal from the rotor driver 18, a current flows from one end of the rotor coil 203 to the other end. That is, current flows from the positive terminal 100 a to the negative terminal 100 b through the E-phase high-side switch element 54, the rotor coil 203, and the F-phase low-side switch element 57.

  For example, when the F-phase high-side switch element 56 and the E-phase low-side switch element 55 are closed, a current flows from the other end of the rotor coil 203 toward one end. That is, current flows from the positive terminal 100 a to the negative terminal 100 b through the F-phase high-side switch element 56, the rotor coil 203, and the E-phase low-side switch element 55.

  The current sensor 70 detects a current amount of the stator coil 204 and the rotor coil 203. More specifically, the current sensor 70 is a shunt resistor provided in the stator inverter 30 and the rotor inverter 50. The current sensor 70 has a U-phase shunt resistor 71, a V-phase shunt resistor 72, a W-phase shunt resistor 73, an E-phase shunt resistor 74, and an F-phase shunt resistor 75.

  The U-phase shunt resistor 71 is provided between the U-phase low-side switch element 35 and the negative electrode terminal 100b. The V-phase shunt resistor 72 is provided between the V-phase low-side switch element 37 and the negative electrode terminal 100b. The W-phase shunt resistor 73 is provided between the W-phase low-side switch element 39 and the negative terminal 100b. The E-phase shunt resistor 74 is provided between the E-phase low-side switch element 55 and the negative terminal 100b. The F-phase shunt resistor 75 is provided between the F-phase low-side switch element 57 and the negative terminal 100b.

  The microcomputer 11 stores the resistance values of these shunt resistors. The microcomputer 11 detects the amount of current flowing through the low-side switch of each leg from the stored resistance value and the voltage across the shunt resistor. Thereby, the microcomputer 11 estimates the amount of current flowing through the stator coil 204 and the rotor coil 203. The current sensor 70 is not limited to the above example. For example, a configuration in which the amount of current is detected based on a magnetic field generated by the flow of current can be employed.

<Overview of ISGECU>
As shown in FIG. 1, the ISGECU 10 includes a microcomputer 11, a rotation angle sensor 12, an induced voltage detection unit 13, and an activation determination unit 14. The ISGECU 10 includes a stator driver 17, a rotor driver 18, and a constant voltage circuit 19. A plurality of elements constituting the ISGECU 10 are mounted on one wiring board. Each of these components is electrically connected via a wiring pattern formed on the wiring board.

  The microcomputer 11 is supplied with power by an activation signal input from the activation determination unit 14. As a result, the microcomputer 11 is activated. More specifically, an activation signal is input from the activation determination unit 14 to the constant voltage circuit 19. As a result, the constant voltage circuit 19 is activated, and generates a voltage of, for example, 5 V necessary for driving the microcomputer 11. This voltage is supplied to the microcomputer 11. As a result, the microcomputer 11 is activated. The microcomputer 11 includes a failure detection unit 15 and a driver control unit 16. Signals of the rotation angle sensor 12 and the induced voltage detection unit 13 are input to the failure detection unit 15. Signals from the rotation angle sensor 12 and the failure detection unit 15 are input to the driver control unit 16.

  The failure detection unit 15 diagnoses the failure of the rotation angle sensor 12 based on the signals of the rotation angle sensor 12 and the induced voltage detection unit 13. Then, the failure detection unit 15 outputs a failure diagnosis result of the rotation angle sensor 12 to the driver control unit 16. The failure detection unit 15 corresponds to a calculation unit.

  The driver control unit 16 generates a control signal based on the failure diagnosis result of the rotation angle sensor input from the failure detection unit 15, the output of the rotation angle sensor 12, and a request command input from the host ECU or the like. This control signal is a pulse signal, and its pulse width is determined according to the output required for the motor 200.

  A control signal generated by the driver control unit 16 is input to the stator driver 17 and the rotor driver 18. The stator driver 17 and the rotor driver 18 amplify the input control signal. Each driver outputs the amplified control signal to the stator inverter 30 and the rotor inverter 50 as a drive signal.

  Note that a starter motor is mounted on the vehicle. When the engine 300 is first started by the starter motor, the driver control unit 16 is started by the start signal input from the start determination unit 14. When the engine 300 is restarted by the motor 200, the ignition signal is input to the ISGECU 10 and is already in the activated state.

<Details of ISGECU>
Details of the ISGECU will be described below.

  The rotation angle sensor 12 detects the rotation angle of the shaft on which the rotor 201 is provided. That is, the rotation angle sensor 12 detects the rotation angle of the motor 200. As described above, a pulley is provided at the tip of the shaft. A belt 310 is attached to this pulley. A permanent magnet 208 shown in FIG. 1 is fixed to the end of the shaft opposite to the tip where the pulley is provided.

  The rotation angle sensor 12 has a plurality of Hall elements arranged to face the permanent magnet 208. A magnetic field generated from the permanent magnet 208 is transmitted through each of the plurality of Hall elements. As the shaft rotates, the angle of the magnetic field that passes through each Hall element changes sequentially. As a result, a Hall voltage whose phase changes according to the rotation of the shaft is output from each Hall element. Each Hall element is arranged apart in the rotation direction of the shaft so that the phase of the output Hall voltage is different.

  The rotation angle sensor 12 has a counter. The count number of this counter is incremented according to the phase change of the Hall voltage of each Hall element. This count number is input to the driver control unit 16 and the failure detection unit 15. The count is cleared when the shaft makes one rotation at the mechanical angle. FIG. 4 shows this count number by a one-dot chain line. The count number increases as the mechanical angle goes from 0 ° to 360 °.

  As described above, the shaft and the crankshaft can be rotated with each other via the belt 310. The belt 310 is provided on a pulley provided on the shaft. The belt 310 is provided on a crankshaft pulley (crankshaft pulley). When these two pulleys have the same diameter, the rotational speed of the crankshaft and the rotational speed of the shaft are the same. Therefore, the rotation speeds of the engine 300 and the motor 200 are the same. However, the diameters of these pulleys are usually different. Therefore, the rotation speed detected by rotation angle sensor 12 is not equal to the rotation speed of engine 300. The ratio of the rotational speed detected by the rotational angle sensor 12 and the rotational speed of the engine 300 is determined by the pulley diameter ratio (pulley ratio).

  The induced voltage detector 13 detects an induced electromotive force (induced voltage) generated by the time change of the magnetic field emitted from the rotor 201 and transmitted through the stator coil 204. The induced voltage detector 13 of this embodiment detects the induced voltages of the U-phase stator coil 205 and the V-phase stator coil 206, respectively. The induced voltage detector 13 detects a voltage difference (line voltage) between the two-phase stator coils.

  As shown in FIG. 3, the induced voltage changes like a sine wave. In FIG. 3, the induced voltage of the U-phase stator coil 205 is indicated by a solid line as PU. The induced voltage of the V-phase stator coil 206 is indicated by a broken line as PV. The induced voltage of the W-phase stator coil 207 is indicated by a one-dot chain line as PW.

  As shown in FIG. 3, the induced voltages of the stator coils are out of phase. Therefore, the line voltage, which is the difference between these induced voltages, also changes like a sine wave as shown by the solid line in FIG. This line voltage is the difference between the induced voltage of the U-phase stator coil 205 and the induced voltage of the V-phase stator coil 206 detected by the induced voltage detector 13. FIG. 4 shows the line voltage when the stator inverter 30 stops driving and is rotated by the engine 300 and rotating at a constant speed.

  The number of magnetic pole pairs of the rotor coil 203 of this embodiment is 8. In this case, the line voltage outputs a sine wave for eight cycles while the shaft rotates 360 ° in mechanical angle. Therefore, when the shaft rotates 45 ° in mechanical angle, the line voltage outputs a sine wave for one cycle. Thus, the electrical angle 360 ° is equal to the mechanical angle 45 °. The line voltage having this sine waveform is input to each of the failure detection unit 15 and the activation determination unit 14.

  As described above, the rotor coil 203 and a part of the fixing portion that fixes the rotor coil 203 to the shaft are magnetized. Therefore, even if the rotor coil 203 is not energized, a magnetic field is output from the rotor 201 although it is weak. The rotor 201 that generates a weak magnetic field is rotated by the crankshaft when the engine 300 is started. Thereby, the time change of the weak magnetic field passing through the stator coil 204 is accelerated. The voltage level of the induced voltage generated in the stator coil 204 is increased. A change in the voltage level of the induced voltage is detected by the induced voltage detector 13.

  The start determination unit 14 determines whether or not the engine 300 has been started and is in a driving state from the temporal behavior of the line voltage input from the induced voltage detection unit 13. If the start determination unit 14 determines from the time behavior of the line voltage that the engine 300 is started and is rotating at a rotational speed equal to or higher than idling, it outputs a high level start signal to the driver control unit 16. On the other hand, when determining that the engine 300 is stopped, the activation determination unit 14 outputs a low-level activation signal to the driver control unit 16.

  The failure detection unit 15 has the functional elements shown in FIG. That is, the failure detection unit 15 includes a comparison unit 15a, an acquisition unit 15b, and a determination unit 15c. These three elements are only shown separately for convenience in order to explain the function of the failure detection unit 15. The components that control the functions of the failure detector 15 may be the same in hardware or may be separated.

  The comparison unit 15 a generates a comparison signal corresponding to the line voltage input from the induced voltage detection unit 13. This comparison signal is input to the acquisition unit 15b. Further, the rotation angle detected by the rotation angle sensor 12 is input to the acquisition unit 15b. The acquisition unit 15b acquires the rotation angle when the comparison signal input from the comparison unit 15a is input. The acquisition unit 15b outputs the acquired rotation angle to the determination unit 15c. The determination unit 15c takes the difference between the plurality of input rotation angles. Then, the determination unit 15c compares the rotation angle difference with the stored phase interval. If the two match, the determination unit 15 c outputs a low-level diagnostic signal indicating that the rotation angle sensor 12 is normal to the driver control unit 16. If they do not match, the determination unit 15c outputs a high-level diagnostic signal indicating that the rotation angle sensor 12 is abnormal to the driver control unit 16. The failure detection unit 15 will be described in detail later.

  The driver control unit 16 is activated when a high-level activation signal is input from the activation determination unit 14. When activated, the driver control unit 16 starts transmitting / receiving information necessary for vehicle control to / from an in-vehicle ECU such as a host ECU. Further, the driver control unit 16 determines whether or not the diagnostic signal input from the failure detection unit 15 is at a high level.

  When the diagnostic signal is at a low level, the driver control unit 16 generates a control signal based on a detection signal from the rotation angle sensor 12 or a request command input from the host ECU. On the other hand, when the diagnostic signal is at a high level, the driver control unit 16 stops outputting the control signals of the stator driver 17 and the rotor driver 18. Alternatively, the driver control unit 16 stops outputting the control signal to the stator driver 17 and continues outputting the control signal to the rotor driver 18. The output of the control signal to the rotor driver 18 is performed when the battery 400 is charged by generating an induced electromotive force in the stator coil 204. The induced electromotive force generated by the stator coil 204 is supplied to the battery 400 via a parasitic diode of a switch element that constitutes the stator inverter 30.

  Each of the stator driver 17 and the rotor driver 18 has an amplifier circuit. These drivers amplify the input control signal, and output the amplified control signal (drive signal) to the gate electrode of the switch element of each inverter. Thereby, the drive of each inverter is controlled.

<Detailed configuration of failure detection unit>
As described above, the failure detection unit 15 includes the comparison unit 15a, the acquisition unit 15b, and the determination unit 15c as functional elements. The comparison unit 15 a has a predetermined comparison threshold value for comparison with the line voltage input from the induced voltage detection unit 13. The comparator 15a outputs a low level when the line voltage is below the comparison threshold. However, the comparator 15a outputs a high level comparison signal when the line voltage exceeds the comparison threshold. Thus, at the timing when the line voltage exceeds the comparison threshold, the comparison signal is switched from the low level to the high level. The comparison signal is switched from the high level to the low level at a timing when the line voltage falls below the comparison threshold. The acquisition unit 15b detects a change in the voltage level of the comparison signal.

  In the following description, the timing at which the comparison signal switches from the low level to the high level is referred to as the rising timing for the sake of simplicity. The timing for switching from the high level to the low level is referred to as the falling timing. This rise timing corresponds to the rise time. The fall timing corresponds to the fall time.

  FIG. 4 shows the comparison threshold value with a broken line. Thus, the comparison threshold is a constant value. As described above, the line voltage outputs a sine wave for eight cycles while the shaft rotates 360 ° in mechanical angle. Therefore, the line voltage exceeds the comparison threshold value 8 times while the shaft rotates 360 ° in mechanical angle. Therefore, the phase interval of the output timing of the high-level comparison signal output from the comparison unit 15a is 45 ° in mechanical angle. In other words, the phase interval of the rising timing of the comparison signal is 45 ° in mechanical angle.

  The acquisition unit 15b of the present embodiment detects the rising timing of the comparison signal. The acquisition unit 15b ignores the falling timing of the comparison signal. The acquisition unit 15b acquires the count number (rotation angle) detected by the rotation angle sensor 12 when the rising timing is detected. The acquisition unit 15b outputs the acquired count number to the determination unit 15c. The rising timing corresponds to the detection time.

  The determination unit 15c calculates the difference in the count number (rotation angle) input from the acquisition unit 15b. As described above, the phase interval of the rising timing is 45 ° in mechanical angle. For this reason, the difference in the number of counts input from the acquisition unit 15b is also expected to be 45 ° in mechanical angle.

  The determination unit 15c has a nonvolatile memory. The nonvolatile memory stores a mechanical angle of 45 ° as a phase interval for failure determination. The determination unit 15c determines whether or not the calculated rotation angle difference is equal to the stored phase interval. That is, the determination unit 15c determines whether or not the calculated rotation angle difference is equal to 45 ° in mechanical angle. When the difference in rotation angle is equal to 45 ° in mechanical angle, the determination unit 15c determines that the rotation angle sensor 12 is normal. On the other hand, if the difference value does not indicate 45 ° in mechanical angle, the determination unit 15c determines that the rotation angle sensor 12 is abnormal.

  When the rotation angle sensor 12 is normal, for example, as shown in FIG. 4, the rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold at time t1 is 45 ° in mechanical angle. Thereafter, the rotation angle detected by the rotation angle sensor 12 at a time t2 when the line voltage again exceeds the comparison threshold value is 90 ° in mechanical angle. Therefore, the difference between the rotation angles detected by the rotation angle sensor 12 at each of the times t1 and t2 is 45 ° in mechanical angle.

  Equivalently, the rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold at time t3 is 235 ° in mechanical angle. Thereafter, at time t4 when the line voltage again exceeds the comparison threshold, the rotation angle detected by the rotation angle sensor 12 is 270 ° in mechanical angle. Therefore, the difference between the rotation angles detected by the rotation angle sensor 12 at each of the times t3 and t4 is 45 ° in mechanical angle. Thus, when the rotation angle sensor 12 is normal, the difference in rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold value is 45 ° in mechanical angle.

  However, if an abnormality occurs in the rotation angle sensor 12, a difference occurs between the phase interval when the line voltage exceeds the comparison threshold and the difference in rotation angle detected by the rotation angle sensor 12 at that time. For example, as shown in FIG. 5, it is assumed that an abnormality occurs in the rotation angle sensor 12 at time ta, and the count number output by the rotation angle sensor 12 becomes a constant value at 120 °. Since the difference in rotation angle of the rotation angle sensor 12 detected at time t1 and time t2 prior to the failure time ta is 45 °, it is determined to be normal. However, the rotation angle of the rotation angle sensor 12 detected at each of the times t3 and t4 after the failure time ta becomes constant at 120 °. Therefore, the difference in the rotation angle of the rotation angle sensor 12 detected at time t3 and time t4 is 0 °, and it is determined as abnormal.

<Fault detection flow of the fault detection unit>
Next, the failure detection flow of the failure detection unit 15 will be described with reference to FIG. This failure detection flow is executed when an induced voltage is generated in the stator coil 204. Specifically, the failure detection flow is performed when the engine 300 is in the combustion drive state and the drive of the switch elements constituting the stator inverter 30 is stopped.

  Each step of this failure detection flow is processed by each functional element of the failure detection unit 15 described above. However, if each functional flow is described separately in each processing flow, the description may be complicated. In order to avoid this, in the following, it is described that the failure detection unit 15 including each of these functional elements processes each step of the failure detection flow collectively.

  The failure detection unit 15 has a volatile memory. Specifically, the determination unit 15c has this volatile memory. This volatile memory has a first angle θ1, a second angle θ2, and a flag N. These are sequentially updated in accordance with the behavior of the line voltage with respect to the comparison threshold as described below.

  First, in step S10, the failure detection unit 15 initializes the volatile memory. Thereby, the failure detection unit 15 sets each of the first angle θ1, the second angle θ2, and the flag N to zero. Next, the failure detection unit 15 proceeds to step S20.

  This step S10 is an initialization process performed when the failure detection unit 15 switches from the preparation state to the activation state. Once the failure detection unit 15 performs this initialization process, it does not perform it again as long as the activation state is maintained. The failure detection unit 15 sequentially repeats the following step S20 and subsequent steps. The diagnostic signal output to the failure detection unit 15 or the driver control unit 16 when the preparation state is switched to the activation state is at a low level.

  In step S20, the failure detection unit 15 determines whether or not the line voltage input from the induced voltage detection unit 13 exceeds the comparison threshold value. If the line voltage exceeds the comparison threshold, the failure detection unit 15 proceeds to step S30. On the other hand, when the line voltage does not exceed the comparison threshold, the failure detection unit 15 enters a standby state in which step S20 is repeated.

  In step S30, the failure detection unit 15 acquires the count number (rotation angle θs) input from the rotation angle sensor 12 when the line voltage exceeds the comparison threshold. Thereafter, the failure detection unit 15 proceeds to step S40.

  Note that the processing order of step S20 and step S30 may be changed as shown in FIG. When processing step S30 after step S10, the failure detection unit 15 sequentially acquires the rotation angle θs input from the rotation angle sensor 12. Then, the failure detection unit 15 proceeds to step S20. In step S20, the failure detection unit 15 acquires the rotation angle θs when the line voltage exceeds the comparison threshold. Then, the failure detection unit 15 proceeds to step S40. On the other hand, when the line voltage does not exceed the comparison threshold, the failure detection unit 15 returns to step S30. Then, the failure detection unit 15 enters a standby state in which steps S30 and S20 are repeated.

  In step S40, the failure detection unit 15 stores the rotation angle θs acquired in step S30 in the first angle θ1 of the volatile memory. In other words, the failure detection unit 15 sets the first angle θ1 to the rotation angle θs acquired in step S30. Thereafter, the failure detection unit 15 proceeds to step S50.

  In step S50, the failure detection unit 15 determines whether or not the volatile memory flag N is zero. If the flag N is 0, the failure detection unit 15 proceeds to step S60. On the other hand, when the flag N is 1, the failure detection unit 15 proceeds to step S70.

  As described above, the flag N is 0 immediately after the initialization process is performed in step S10. Therefore, in this case, the failure detection unit 15 proceeds to step S60.

  In step S60, the failure detection unit 15 changes the flag N from 0 to 1. After this, the failure detection unit 15 proceeds to step S80.

  In step S80, the failure detection unit 15 stores the first angle θ1 set in step S40 in the second angle θ2 of the volatile memory. After this, the failure detection unit 15 returns to step S20.

  In this case, the rotation angle θs set in the previous step S30 is stored in each of the first angle θ1 and the second angle θ2. Thereafter, when the failure detection unit 15 executes Steps S20 to S40, the new rotation angle θs is stored in the first angle θ1. This new rotation angle θs is expected to be a rotation angle whose phase is 45 ° ahead of the previous rotation angle θs.

  When the process proceeds to step S50, since the flag N has already been set to 1, the failure detection unit 15 proceeds to step S70.

  In step S70, the failure detection unit 15 calculates the absolute value of the difference between the first angle θ1 and the second angle θ2 stored so far in the volatile memory. After this, the failure detection unit 15 proceeds to step S90.

  In step S90, the failure detection unit 15 determines whether or not the absolute value of the difference between the first angle θ1 and the second angle θ2 calculated in step S70 is equal to the stored phase interval (mechanical angle 45 °). to decide. When the absolute value is equal to the mechanical angle 45 °, the failure detection unit 15 proceeds to step S80 and updates the second angle θ2 to a new rotation angle. In this case, the diagnostic signal remains at a low level. However, if the absolute value is not equal to the mechanical angle 45 °, the failure detection unit 15 proceeds to step S100.

  In step S100, the failure detection unit 15 switches the output level of the diagnostic signal from the low level to the high level. As a result, the failure detection unit 15 notifies the driver control unit 16 of the failure of the rotation angle sensor 12. After this, the failure detection unit 15 ends this failure detection flow.

<Effect>
Next, the function and effect of the motor control device 100 according to the present embodiment will be described. As described above, the rotation angle sensor 12 fails depending on whether or not the difference in rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold by 2 degrees is equal to 45 ° in mechanical angle. Can be judged. According to this, for example, an increase in the number of parts is suppressed compared to a configuration in which a failure of the rotation angle sensor is determined based on detection results of a plurality of rotation angle sensors.

  When the diagnostic signal is at a high level, the driver control unit 16 stops outputting the control signal to the stator driver 17 and continues outputting the control signal to the rotor driver 18. According to this, even if the rotation angle sensor 12 is abnormal, the charging of the battery 400 by the power generation of the motor 200 can be continued.

  The motor control device 100 and the motor 200 have an electromechanical integrated configuration. In particular, U-phase stator coil 205, V-phase stator coil 206, and W-phase stator coil 207 are each integrally connected to motor control device 100 via a bus bar. According to this, compared with the structure which the motor control apparatus 100 and the motor 200 leave | separate and are electrically connected by a wire harness etc., it is suppressed that noise is input into both electrical connection parts.

(First modification)
In the present embodiment, an example has been described in which the acquisition unit 15b detects the rising timing of the comparison signal and ignores the falling timing of the comparison signal. On the other hand, it is possible to adopt a configuration in which the acquisition unit 15b detects the falling timing of the comparison signal and ignores the rising timing of the comparison signal.

(Second modification)
For example, the acquisition unit 15b may employ a configuration in which one rising timing of the comparison signal is detected. In this case, the rotation angle during the rising timing detected by the acquisition unit 15b is expected to be 90 ° in mechanical angle. Therefore, the determination unit 15c stores a mechanical angle of 90 ° as the phase interval.

  For example, as shown in FIG. 8, the rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold at time t1 is 45 ° in mechanical angle. Thereafter, the rotation angle detected by the rotation angle sensor 12 at the time t5 when the line voltage is skipped by one and exceeds the comparison threshold value is 135 ° in mechanical angle. Therefore, the difference between the rotation angles detected by the rotation angle sensor 12 at each of the times t1 and t5 is 90 ° in mechanical angle.

(Second Embodiment)
Next, a second embodiment will be described based on FIG. The motor control device according to each embodiment described below has many common points with those according to the above-described embodiment. Therefore, in the following description, description of common parts is omitted, and different parts are mainly described. In the following description, the same reference numerals are given to the same elements as those described in the above embodiment.

  In the first embodiment, the acquisition unit 15b detects the rising timing of the comparison signal and ignores the falling timing. On the other hand, both the rising timing and falling timing of the comparison signal of the acquisition unit 15b of the present embodiment are detected.

  The acquisition unit 15b of the present embodiment acquires the count number (rotation angle) detected by the rotation angle sensor 12 when detecting the rising timing and the falling timing. The acquisition unit 15b outputs the acquired count number to the determination unit 15c.

  In this case, the difference between the rotation angle at the rising timing and the rotation angle at the falling timing is expected to be 15 ° in mechanical angle. For this purpose, the determination unit 15c of the present embodiment stores a mechanical angle of 15 ° as the phase interval. The determination unit 15c determines whether or not the calculated rotation angle difference is equal to 15 ° in mechanical angle. Thereby, it is determined whether the rotation angle sensor 12 is normal or abnormal.

  For example, as shown in FIG. 9, the rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold at time t11 is 45 ° in mechanical angle. Thereafter, at time t12 when the line voltage falls below the comparison threshold, the rotation angle detected by the rotation angle sensor 12 is 60 ° in mechanical angle. Therefore, the difference between the rotation angles detected by the rotation angle sensor 12 at each of the times t11 and t12 is 15 ° in mechanical angle. Similarly, the difference between the rotation angles detected by the rotation angle sensor 12 at the time t13 when the line voltage exceeds the comparison threshold and the time t14 when the line voltage falls below the comparison threshold is 15 ° in mechanical angle.

  As described above, according to this configuration, it is possible to determine a failure of the rotation angle sensor 12 every time the motor 200 rotates 15 ° in mechanical angle. Therefore, failure of the rotation angle sensor 12 can be determined with high frequency.

(Third Modification)
In the present embodiment, an example has been described in which the acquisition unit 15b sequentially detects both the rising timing and the falling timing of the comparison signal. In contrast to this, the acquisition unit 15b may employ a configuration in which each of the rising timing and falling timing of the comparison signal is detected by skipping one. In this case, the rotation angle between the rising timing and falling timing detected by the acquisition unit 15b is expected to be 60 ° in mechanical angle. Therefore, the determination unit 15c stores a mechanical angle of 60 ° as the phase interval.

  For example, as shown in FIG. 10, the rotation angle detected by the rotation angle sensor 12 when the line voltage exceeds the comparison threshold at time t15 is 90 ° in mechanical angle. After that, after the line voltage once falls below the comparison threshold value and once again rises again, the rotation angle detected by the rotation angle sensor 12 at the time t <b> 16 again becomes 150 ° in mechanical angle. Therefore, the difference between the rotation angles detected by the rotation angle sensor 12 at each of the times t15 and t16 is 60 ° in mechanical angle.

  The preferred embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. It is.

(Fourth modification)
In each embodiment, the example in which the induced voltage detection unit 13 outputs the line voltage is shown. However, the induced voltage detection unit 13 may employ a configuration in which an induced voltage of one of the three-phase stator coils is detected and output.

(Other variations)
In each embodiment, the example in which the motor 200 is connected to the crankshaft of the engine 300 mounted on the vehicle via the belt 310 is shown. However, the motor 200 may be configured to be connected to the crankshaft through a power distribution mechanism.

  In each embodiment, an example in which the number of magnetic pole pairs of the rotor coil 203 is eight has been shown. However, the number of magnetic pole pairs of the rotor coil 203 is not limited to the above example, and for example, 4 or 16 can be adopted.

  In each embodiment, the example which the rotor 201 has the rotor coil 203 was shown. However, the rotor 201 may employ a configuration including a permanent magnet instead of the rotor coil 203.

  In each embodiment, the rotor inverter 50 showed the example which comprises the full bridge circuit. However, the rotor inverter 50 may constitute a half bridge circuit.

  In each embodiment, the switch element which comprises the stator inverter 30 and the rotor inverter 50 showed the example which is MOSFET. However, the switch elements constituting the stator inverter 30 and the rotor inverter 50 are not limited to the above example, and for example, an IGBT can be adopted. In this case, a reflux diode is separately connected in reverse parallel to the switch element.

  In each embodiment, the example which a single-sided cooling system is employ | adopted for the switch element which comprises the stator inverter 30 was shown. However, the system for cooling the switching elements constituting the stator inverter 30 is not limited to the above example, and for example, a double-sided cooling system may be adopted. Also, a cooling system using a flowing refrigerant may be employed.

  In each embodiment, the material which forms the stator inverter 30 and the rotor inverter 50 was not mentioned in particular. However, as this forming material, for example, silicon can be employed. As another forming material, for example, silicon carbide having a wider band gap than silicon can be adopted.

  Furthermore, the forming material may be different between the rotor inverter 50 and the stator inverter 30. For example, the rotor inverter 50 may be formed of silicon carbide, and the stator inverter 30 may be formed of silicon.

DESCRIPTION OF SYMBOLS 10 ... ISGECU, 12 ... Rotation angle sensor, 13 ... Induction voltage detection part, 15 ... Failure detection part, 15a ... Comparison part, 15b ... Acquisition part, 15c ... Judgment part, 16 ... Driver control part, 30 ... Stator inverter, 50 DESCRIPTION OF SYMBOLS ... Rotor inverter, 100 ... Motor control apparatus, 200 ... Motor, 201 ... Rotor, 202 ... Stator, 203 ... Rotor coil, 204 ... Stator coil, 205 ... U-phase stator coil, 206 ... V-phase stator coil, 207 ... W-phase Stator coil, 300 ... engine, 400 ... battery

Claims (6)

A control device for a rotating electrical machine (200),
A rotation angle sensor (12) for detecting a rotation angle of the rotor (201) of the rotating electrical machine;
An induced voltage detector (13) for detecting an induced voltage of a stator coil (204 to 207) included in the stator (202) of the rotating electrical machine;
The rotation angle detected by the rotation angle sensor and the calculation unit (15) to which each of the induced voltage detected by the induced voltage detection unit is input,
A plurality of rise times when the induced voltage detected by the induced voltage detection unit exceeds a predetermined comparison threshold when the stator inverter (30) that controls energization to the stator coil is stopped; and , A difference between the rotation angles of the two rotors detected by the rotation angle sensor at each of two detection times of a plurality of falling times when falling below the comparison threshold, and between the two detection times A control device that determines a failure of the rotation angle sensor based on a phase interval of the induced voltage.   The control device according to claim 1, wherein the two detection times are two of the plurality of rise times or two of the plurality of fall times.   The control device according to claim 1, wherein the two detection times are one of a plurality of the rising times and one of the plurality of falling times.   The control device according to claim 1, wherein the control device is integrally connected to the rotating electrical machine.   The control device according to any one of claims 1 to 4, wherein when the calculation unit determines that the rotation angle sensor is out of order, the operation of the stator inverter is stopped. The rotor has a field winding (203);
6. The control device according to claim 5, wherein the calculation unit stops driving the rotor inverter (50) that controls energization of the field winding when it determines that the rotation angle sensor has failed. 7.

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