Motor control device

Abstract

This invention provides a motor control device that can appropriately control a motor with a simplified configuration that omits the sensor for detecting the motor's rotational position. [Solution] In the motor control device 100, the control unit 132 sets the timing for switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c, based on a reference signal corresponding to a reference rotation angle that has been set in advance as a reference rotation angle for the rotation angle of the crankshaft 7.

Description

Technical Field

[0001] The present invention relates to a motor control device.

Background Art

[0002] In recent years, in vehicles such as automobiles, a three-phase alternator including a rotor having a field flux generating magnet connected to a crankshaft (crankshaft) of an internal combustion engine and driven along with its rotation, and a stator around which a stator winding for generating power output is wound is used as a starting motor for the internal combustion engine. A motor control device has been proposed that controls charging of a secondary battery such as a lead battery mounted on a vehicle and controls starting of the internal combustion engine by rotating its crankshaft.

[0003] Under such circumstances, Patent Document 1 relates to a four-stroke engine unit for a vehicle and a vehicle. The control device of the engine unit includes a plurality of detected portions provided on the outer surface of the outer rotor of the starter motor, a rotor position detection device having a detection winding provided separately from the stator winding of the starter motor, and a plurality of switching portions. From a control mode in which the plurality of switching portions are turned on and off at a predetermined timing to start the forward rotation of the crankshaft, based on the timing of an electrical signal flowing through the detection winding of the rotor position detection device that changes due to a change in the magnetic state when the plurality of detected portions move along with the forward rotation of the crankshaft, the plurality of switching portions are turned on and off to accelerate the forward rotation of the crankshaft. A configuration for shifting to a control mode is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, according to the inventor's research, the configuration disclosed in Patent Document 1 includes a rotor position detection device for detecting the rotational position of the starter motor. However, in vehicles such as motorcycles, for example, simplification of the configuration is required, and therefore, it is desirable to omit sensors that detect the rotational position of the motor, such as rotor position detection devices. In other words, Patent Document 1 does not disclose anything regarding the omission of such a sensor for detecting the rotational position of the motor from its configuration, nor does it disclose what kind of configuration should be adopted to appropriately drive the motor and generate power when such a sensor is omitted. In short, currently, there is a strong desire for the realization of a novel configuration that can appropriately control motor driving and power generation even when a sensor for detecting the rotational position of the motor is omitted.

[0006] The present invention was made after the above considerations, and aims to provide a motor control device that can appropriately control the operation of a motor with a simplified configuration that omits a sensor for detecting the rotational position of the motor. [Means for solving the problem]

[0007] To achieve the above objectives, the present invention provides a motor control device that drives a motor that rotates the crankshaft of an internal combustion engine to start the internal combustion engine by switching the energizing state of each phase of the current supplied to the motor, and to which a signal corresponding to the rotation angle of the crankshaft is input, wherein one aspect is that the timing for switching the energizing state of at least one of the phases is set based on a reference signal which is a signal corresponding to a reference rotation angle that serves as a reference for the rotation angle. [Effects of the Invention]

[0008] According to the motor control device in the first aspect of the present invention described above, the motor is driven by switching the energization state of each phase of the current supplied to the motor that rotates the crankshaft of the internal combustion engine to start the internal combustion engine, and a signal corresponding to the rotation angle of the crankshaft is input to the motor control device, and the timing for switching the energization state of at least one phase of each phase is set based on a reference signal which is a signal that corresponds to a reference rotation angle that serves as a reference for the rotation angle. As a result, the operation of the motor can be appropriately controlled in accordance with the rotation angle of the crankshaft with a simplified configuration that omits a sensor for detecting the rotation position of the motor. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1(a) is a schematic diagram showing a motor control device in an embodiment of the present invention together with an internal combustion engine, an engine control device, and a three-phase AC generator motor, and Figure 1(b) is an enlarged view of the recurctor shown in Figure 1(a). [Figure 2] Figure 2 is a schematic diagram showing the circuit configuration and functional blocks of the motor control device in this embodiment, together with the engine control device and motor. [Figure 3] Figure 3 is a time chart showing an example of the operation of the motor control device in this embodiment. [Modes for carrying out the invention]

[0010] Hereinafter, the motor control device according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

[0011] [Engine configuration] First, with reference to Figure 1, the configuration of the engine, which is the controlled object of the engine control system in which the motor control system cooperates in this embodiment, will be described in detail.

[0012] Figure 1(a) is a schematic diagram showing the motor control device in this embodiment together with the engine, engine control device, and motor, and Figure 1(b) is an enlarged view of the recurctor shown in Figure 1(a).

[0013] As shown in Figures 1(a) and 1(b), the engine 1, which is an internal combustion engine, is typically mounted on a vehicle such as a motorcycle (not shown), has a four-stroke cycle, and its operation is controlled by an engine control device 50. It is equipped with a cylinder block 2. Cooling water passages 3 are formed within the side walls of the cylinder block 2, through which cooling water flows to cool the cylinder block 2 and its interior. A water temperature sensor 4 is provided in the cooling water passages 3 to detect the temperature of the cooling water flowing through them.

[0014] For the sake of explanation, the engine 1 is shown as a single-cylinder engine in the diagram, but the engine 1 may have multiple cylinders, and the cylinder arrangement may be in line, horizontally opposed, V-type, etc. Also, for the sake of explanation, the engine 1 is shown as water-cooled in the diagram, but it may be air-cooled, in which case a temperature sensor capable of detecting the temperature of the engine 1 may be mounted on the cylinder block 2, etc., instead of the water temperature sensor 4.

[0015] A piston 5 is located inside the cylinder block 2. The piston 5 is connected to a crankshaft 7, which has a rotation axis, via a connecting rod 6. A recurctor 70 is mounted on the crankshaft 7 coaxially with its rotation axis. Multiple teeth 72 (72a to 72e, etc.) are arranged continuously at basically constant intervals on the outer circumference of the recurctor 70, but in some predetermined sections there are toothless sections 72f where teeth 72 are absent. A crank angle sensor 8 is provided near the recurctor 70 to detect the rotation angle (rotation position) of the crankshaft 7 around its rotation axis, in order to calculate the rotational speed of the engine 1, etc. A cylinder head 9 is mounted on the top of the cylinder block 2. The internal space defined by the top surface of the piston 5 and the inner surfaces of the cylinder block 2 and cylinder head 9 respectively becomes the combustion chamber 10.

[0016] The cylinder head 9 is provided with a spark plug 11 that ignites the air-fuel mixture in the combustion chamber 10. The ignition operation of the spark plug 11 is controlled by the engine control device 50, which controls the energization state of the ignition coil (not shown in the figure).

[0017] Furthermore, the cylinder head 9 is provided with an intake valve 13 that can open and close to connect the combustion chamber 10 and the intake passage 12. The intake passage 12 is formed in an intake manifold IM mounted on the cylinder head 9, and the intake manifold IM includes a fuel injector 14 that injects fuel into the intake passage 12 and a throttle valve 15 positioned upstream of the fuel injector 14. A throttle opening sensor 106 is provided for the throttle valve 15 to detect its opening degree. In addition, an intake pressure sensor 107 is provided for the fuel injector 14 and the intake passage 12 between the fuel injector 14 to detect the intake pressure of the engine 1. The fuel injection operation (valve opening operation) of the fuel injector 14 is controlled by the energization state of its solenoid valve (not shown) being controlled by the engine control device 50. The fuel injector 14 may also inject fuel directly into the combustion chamber 10. Alternatively, the rotational position of the intake cam of the mechanism that opens and closes the intake valve 13 may be used as the rotational position corresponding to the rotational position of the crankshaft 7.

[0018] An exhaust pipe EM is mounted on the cylinder head 9 opposite the intake pipe IM, and an exhaust passage 16 communicating with the combustion chamber 10 is formed inside the exhaust pipe EM. The cylinder head 9 is provided with an exhaust valve 17 that can open and close to connect the combustion chamber 10 and the exhaust passage 16. The rotational position corresponding to the rotational position of the crankshaft 7 may be the rotational position of the exhaust cam of the mechanism that opens and closes the exhaust valve 17.

[0019] [Configuration and operation of the control device] Next, with further reference to Figures 2 and 3, the configuration of the engine control device and motor control device in this embodiment will be described in detail, along with their operation.

[0020] FIG. 2 is a schematic diagram showing the circuit configuration and functional blocks of the motor control device in the present embodiment together with the engine control device and the motor. FIG. 3 is a time chart showing an example of the operation of the motor control device in the present embodiment. From top to bottom, in order, it shows the change over time of the voltage of the output signal (crank signal) of the crank angle sensor 8, the change over time of the completion state of the stroke determination of the four-stroke cycle of the engine 1, the change over time of the timing state of the timer, the change over time of the energization state of the U-phase of the current supplied to the motor, the change over time of the energization state of the V-phase of the current supplied to the motor, and the change over time of the energization state of the W-phase of the current supplied to the motor. In FIG. 3, the case where the motor is operated with so-called 180-degree energization is shown, but the motor may be operated with so-called 120-degree energization. Also, the length in the time axis direction of the timer shown in the timing state of the timer schematically shows the timing length from the start to the completion of the timing.

[0021] As shown in FIG. 2, the engine control device 50 is started when the starter switch 105 is turned on and controls the operation of the engine 1. Based on output signals and the like sent from the crank angle sensor 8, water temperature sensor 4, throttle opening sensor 106, intake pressure sensor 107, etc., it mainly controls the ignition operation of the ignition plug 11 by controlling the energization state of an ignition coil (not shown) and controls the fuel injection operation (valve opening operation) of the fuel injection valve 14 by controlling the energization state of the fuel injection valve 14. It includes an engine ECU (Electronic Control Unit) 60. The engine ECU 60 is an arithmetic processing device including a microcomputer and the like, and has a memory and a timer (not shown). Necessary control and processing programs and control and processing data are stored in such a memory, and the engine ECU 60 reads out the necessary control and processing programs and control and processing data from the memory and controls the operations of the ignition plug 11, fuel injection valve 14, etc. by executing the control and processing programs.

[0022] In addition to calculating the rotational speed of the engine 1 based on the output signal sent from the crank angle sensor 8, when the voltage value of the output signal sent from the crank angle sensor 8 becomes equal to or higher than a predetermined threshold value, the engine ECU 60 determines that the tooth portion 72 of the reluctor 70 has passed near the crank angle sensor 8, and sends an output signal indicating that the tooth portion 72 has passed near the crank angle sensor 8 to the motor control device 100.

[0023] Here, assuming that the reference rotational position, which is the reference position at the rotational position of the engine 1, that is, the position corresponding to the reference rotational angle that is set in advance to be the reference at the rotational angle of the crankshaft 7, corresponds to the position of the tooth portion 72a at the end of the tooth-missing portion 72f of the recurver 70, then the period from when the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth portion 72b at the beginning of the tooth-missing portion 72f passes near the crank angle sensor 8 until the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth portion 72a at the end of the tooth-missing portion 72f passes near the crank angle sensor 8, the adjacent tooth portion in front of the tooth portion 72b at the beginning of the tooth-missing portion 72f The period is set to be longer than the period from when the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as tooth 72c passes near the crank angle sensor 8, until the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as tooth 72b passes near the crank angle sensor 8, and also longer than the period from when the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as tooth 72a at the end of tooth missing portion 72f passes near the crank angle sensor 8, until the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as tooth 72d adjacent to tooth 72a passes near the crank angle sensor 8.For example, in the recurctor 70, if the angle of the missing tooth portion 72f is set to 45 degrees, and the angles between adjacent teeth 72 other than the missing tooth portion 72f are set to 15 degrees, the period from when the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth 72b at the beginning of the missing tooth portion 72f passes near the crank angle sensor 8, until the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth 72a at the end of the missing tooth portion 72f passes near the crank angle sensor 8, corresponds to an angle of 45 degrees. The period from when the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth 72c passes near the crank angle sensor 8, until the voltage value of the output signal sent from the crank angle sensor 8 exceeds a predetermined threshold as the tooth 72b passes near the crank angle sensor 8, corresponds to an angle of 15 degrees. Furthermore, the output signal sent from the crank angle sensor 8 may be directly input to the motor control device 100 without going through the engine control device 50. In this case, the motor ECU 130 of the motor control device 100 will have a function equivalent to that of the engine ECU 60, which processes the output signal sent from the crank angle sensor 8.

[0024] Furthermore, the motor control device 100 includes a motor ECU 130 for controlling the operation of the motor 110, which is a three-phase AC generator motor. Specifically, the motor ECU 130 is activated when the starter switch 105 is turned ON, and charges the lead-acid battery 101, which is a secondary battery, by generating power with the motor 110. At the same time, it uses the motor 110 as a starter motor to rotate the crankshaft 7 of the engine 1, thereby starting the engine 1 in cooperation with the engine ECU 60 as needed. In addition to lead-acid batteries, nickel-metal hydride batteries and lithium-ion batteries can also be used as secondary batteries. Also, in the figure, reference numeral 102 indicates a load connected to the lead-acid battery 101. Note that the engine control device 50 and the motor control device 100 may not be separate units but may constitute a single integrated control device.

[0025] Although the detailed configuration of the motor 110 is omitted, it is typically controlled by PWM (Pulse Width Modulation) and comprises a stator around which three-phase power generation coils (stator windings) consisting of a U-phase coil 110a, a V-phase coil 110b, and a W-phase coil 110c are wound, and a rotor which is mounted on the outer circumference of the stator and has permanent magnets for generating field flux corresponding to each of these phase coils 110a, 110b, and 110c attached to it. This rotor is mechanically connected to the crankshaft 7 of the engine 1 via a reduction gear system (not shown). Therefore, via this gear system, there is a one-to-one correspondence between the rotational position of the motor 110, that is, the rotational position of the rotor (rotational position around the rotation axis 112 schematically shown in Figure 1), and the rotational position of the engine 1, that is, the rotational position of the crankshaft 7.

[0026] The U-phase coil 110a has a connection terminal 111a that electrically connects to the other terminal of one U-phase switching element 131a of the AC / DC converter 131 and to one terminal of the other U-phase switching element 131b of the AC / DC converter 131. The V-phase coil 110b has a connection terminal 111b that electrically connects to the other terminal of one V-phase switching element 131c of the AC / DC converter 131 and to one terminal of the other V-phase switching element 131d of the AC / DC converter 131. The W-phase coil 110c has a connection terminal 111c that electrically connects to the other terminal of one W-phase switching element 131e of the AC / DC converter 131 and to one terminal of the other W-phase switching element 131f of the AC / DC converter 131.

[0027] The motor ECU 130 is a processing unit including a microcomputer, and has memory and timers (not shown in the diagram). The memory stores the necessary control and processing programs and control and processing data. The motor ECU 130 reads the necessary control and processing programs and data from the memory and executes the control and processing programs to control the operation of the motor 110, which is a generator motor.

[0028] Specifically, the motor ECU 130 includes an AC (Alternate Current) / DC (Direct Current) converter 131, which is a power converter, and a control unit 132 that sends control signals to the AC / DC converter 131 to control its operation, drives the engine 1 to start the engine 1, and controls the motor 110 to generate power when driven by the engine 1. The motor ECU 130 also includes a voltage receiving circuit 133 that receives the voltage between the other terminal of the U-phase switching element 131a and one terminal of the U-phase switching element 131b and the connection terminal 111a of the U-phase coil 110a, the voltage between the other terminal of the V-phase switching element 131c and one terminal of the V-phase switching element 131d and the connection terminal 111b of the V-phase coil 110b, and the voltage between the other terminal of the V-phase switching element 131c and one terminal of the V-phase switching element 131d and the connection terminal 111b of the V-phase coil 110b. The motor ECU 130 can detect the energization status of the U-phase, V-phase, and W-phase of the current supplied to the motor 110 based on the voltage value received by the voltage receiving circuit 133. In the figure, the control unit 132 is shown as a functional block for executing the control program.

[0029] The AC / DC converter 131 typically has three-phase bridged switching elements 131a, 131b, 131c, 131d, 131e, and 131f, and converts the three-phase AC current supplied from the motor 110 into DC current by turning each of the switching elements 131a, 131b, 131c, 131d, 131e, and 131f on or off according to a control signal from the control unit 132, and also supplies the DC current to the lead-acid battery 101. In this case, the motor 110 is driven by the engine 1 and functions as a generator that is so-called retarded by the control unit 132 via the AC / DC converter 131. Furthermore, the AC / DC converter 131 converts the DC current supplied from the lead-acid battery 101 into a three-phase AC current by turning on or off each of the switching elements 131a, 131b, 131c, 131d, 131e, and 131f according to the control signal from the control unit 132, and supplies this three-phase AC current to the motor 110. In this case, the AC / DC converter 131 functions as a DC / AC converter, and the motor 110 functions as a starter motor that drives the engine 1 by transmitting the rotation of its rotor to the crankshaft 7 of the engine 1 via the reduction gear system. Note that the switching elements 131a, 131b, 131c, 131d, 131e, and 131f are typically transistors, and in Figure 2, they are shown as N-type MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) as an example. Furthermore, instead of using motor 110 as a multi-purpose starter motor, a separate, dedicated starter motor without a power generation function may be used.

[0030] Specifically, the AC / DC converter 131 has a pair of switching elements 131a, 131b, 131c, 131d, 131e, and 131f corresponding to each of the three phases: U-phase, V-phase, and W-phase.

[0031] In other words, in the AC / DC converter 131, a pair of U-phase switching elements 131a and 131b are electrically connected. When switching element 131a is ON and switching element 131b is OFF, the U-phase drive voltage is set to a high level, and when switching element 131a is OFF and switching element 131b is ON, the U-phase drive voltage is set to a low level.

[0032] Furthermore, in the AC / DC converter 131, a pair of V-phase switching elements 131c and 131d are electrically connected. When switching element 131c is ON and switching element 131d is OFF, the V-phase drive voltage is set to a high level, and when switching element 131c is OFF and switching element 131d is ON, the V-phase drive voltage is set to a low level.

[0033] Furthermore, in the AC / DC converter 131, a pair of W-phase switching elements 131e and 131f are electrically connected. When switching element 131e is ON and switching element 131f is OFF, the W-phase drive voltage is set to a high level, and when switching element 131e is OFF and switching element 131f is ON, the W-phase drive voltage is set to a low level.

[0034] Here, the switching element 131a has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high-potential side of the lead-acid battery 101, and the other input terminal electrically connected to the connection terminal 111a of the switching element 131b and the motor 110. The switching element 131a turns on and off according to a predetermined control signal applied to its control terminal from the control unit 132, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0035] Furthermore, the switching element 131b has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the connection terminal 111a of the switching element 131a and the motor 110, and the other input terminal electrically connected to the low potential side of the lead battery 101. The switching element 131b turns on and off according to a predetermined control signal applied from the control unit 132 to its control terminal, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0036] Furthermore, the switching element 131c has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high-potential side of the lead-acid battery 101, and the other input terminal electrically connected to the connection terminal 111b of the switching element 131d and the motor 110. The switching element 131c turns on and off according to a predetermined control signal applied to its control terminal from the control unit 132, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0037] Furthermore, the switching element 131d has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the switching element 131c and the connection terminal 111b of the motor 110, and the other input terminal electrically connected to the low potential side of the lead battery 101. The switching element 131d turns on and off according to a predetermined control signal applied from the control unit 132 to its control terminal, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0038] Furthermore, the switching element 131e has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high-potential side of the lead-acid battery 101, and the other input terminal electrically connected to the switching element 131f and the connection terminal 111c of the motor 110. The switching element 131e turns on and off according to a predetermined control signal applied to its control terminal from the control unit 132, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0039] Furthermore, the switching element 131f has a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the switching element 131e and the connection terminal 111c of the motor 110, and the other input terminal electrically connected to the low potential side of the lead battery 101. The switching element 131f turns on and off according to a predetermined control signal applied from the control unit 132 to its control terminal, and when it is in the ON state, current flows from one input terminal to the other input terminal.

[0040] In other words, the control unit 132 can switch the current flowing through the U-phase coil 110a by setting the U-phase drive voltage to a high level when switching element 131a is ON and switching element 131b is OFF, and setting the U-phase drive voltage to a low level when switching element 131a is OFF and switching element 131b is ON, and by setting the V-phase drive voltage to a high level when switching element 131c is ON and switching element 131d is OFF, When the switch element 131d is in the off state and the switching element 131d is in the on state, the drive voltage of the V phase can be set to a low level, thereby switching the current flowing through the V phase coil 110b. Also, when the switch element 131e is in the on state and the switching element 131f is in the off state, the drive voltage of the W phase can be set to a high level, and when the switch element 131e is in the off state and the switching element 131f is in the on state, the drive voltage of the W phase can be set to a low level, thereby switching the current flowing through the W phase coil 110c. Here, in a simplified configuration that omits the sensor for detecting the rotational position of the motor 110, the control unit 132 determines the rotational position of the motor 110 around the rotation axis 112 from the rotation angle (rotational position) around the rotation axis of the crankshaft 7, and sets the timing for switching the energization state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c, based on a reference signal corresponding to a reference rotation angle that has been set in advance as a reference rotation angle for the rotation angle of the crankshaft 7. Furthermore, from the viewpoint of properly operating the motor 110, especially properly accelerating its forward rotation, since there are a total of six types of combinations of permanent magnet polarity (motor position stages) for each phase from the U-phase to the W-phase in the motor 110, it is preferable for the control unit 132 to appropriately switch the current of each phase from the U-phase to the W-phase for these six types of motor position stages.When operating the motor 110 with so-called 180-degree energization, the energization state of each phase is switched by switching the drive voltage of each phase from the U phase to the W phase between high and low levels. However, when operating the motor 110 with so-called 120-degree energization, the energization state of each phase is switched by switching the drive voltage of each phase from the U phase to the W phase between high or low levels and zero. If necessary, it is also possible to switch the energization state of the current flowing through the U phase coil 110a, the V phase coil 110b, and the W phase coil 110c simultaneously or with a predetermined time difference, in an appropriate combination.

[0041] Furthermore, when the teeth 72c of the recurctor 70, which are in front of teeth 72a and 72b, pass near the crank angle sensor 8, and the voltage of the output signal sent from the crank angle sensor 8 corresponding to teeth 72c and input to the engine ECU 60 reaches a predetermined threshold, the first signal, which is an output signal sent from the engine ECU 60 and input to the motor ECU 130, is generated when the teeth 72b of the recurctor 70, which are in front of teeth 72a, pass near the crank angle sensor 8. When the voltage of the output signal sent from the crank angle sensor 8 corresponding to the teeth 72b and input to the engine ECU 60 reaches a predetermined threshold as the tooth 72a of the recurctor 70 passes nearby, the voltage of the output signal sent from the crank angle sensor 8 corresponding to the tooth 72a and input to the engine ECU 60 reaches a predetermined threshold, and the voltage of the output signal sent from the crank angle sensor 8 corresponding to the tooth 72a and input to the engine ECU 60 as the tooth 72a of the recurctor 70 passes nearby to the crank angle sensor 8 Assuming that a reference signal, which is an output signal sent from the engine ECU 60 and input to the motor ECU 130 when a predetermined threshold is reached, is input to the motor ECU 130 in this order (the interval between the second signal and the reference signal, that is, the time interval between the timing when the voltage of the second signal reaches a predetermined threshold and the timing when the voltage of the reference signal reaches a predetermined threshold, is longer than the interval between the first signal and the second signal, that is, the time interval between the timing when the voltage of the first signal reaches a predetermined threshold and the timing when the voltage of the second signal reaches a predetermined threshold), from the viewpoint of more appropriately controlling the rotational operation of the motor 110, it is preferable that the control unit 132 sets the timing to switch the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c during the period from when the first signal, the second signal, and the reference signal are each input in order for the nth time (n is a natural number) until when the second signal is input for the n+1th time and the reference signal is input for the n+1th time, in order to more appropriately control the rotational operation of the motor 110.

[0042] Furthermore, from the viewpoint of more appropriately controlling the rotational operation of the motor 110, it is preferable that the control unit 132 sets a timing for switching the energization state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c during the period from when the second signal is input for the (n+1)th time until the reference signal is input for the (n+1)th time, based on the timing when the second signal is input for the (n+1)th time.

[0043] Furthermore, since the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 indicates the change in the crank angle of the engine 1 in time series, and considering that such an output signal corresponds to each stroke in the engine's four-stroke cycle, it is preferable that the control unit 132 further sets the timing for switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c, based on the result of identifying the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the strokes in the engine's four-stroke cycle. In this case, it is preferable that the control unit 132 determines the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the engine stroke, based on the timing when the first signal, second signal, and reference signal are input in succession for the nth time, the timing when the first signal, second signal, and reference signal are input in succession for the (n+1)th time, and the timing when the first signal, second signal, and reference signal are input in succession for the (n+2)th time. When the compression stroke of the engine 1 is determined, considering that the rotational speed of the crankshaft 7 tends to decrease during the compression stroke, it is possible to adjust the timing of switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c to be delayed compared to other strokes. When such adjustment is made by adjusting the timing of the timer (program timer), the timing may be extended by a predetermined percentage from the previous one (for example, setting a switching delay time of about 10%).

[0044] Furthermore, considering that the intake pressure of engine 1 is closely related to the stroke of engine 1, it is preferable that the control unit 132 further determines the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the stroke of the engine, based on the intake pressure of engine 1 calculated based on the output signal sent from the intake pressure sensor 107, etc.

[0045] In the above configuration, an example of the operation of the motor control device 100 will be explained in detail with reference to Figure 3. For convenience, in the figure, after the motor 110 rotates the crankshaft 7 of the engine 1 and the engine 1 is started, the first time when the voltage of each output signal (crank signal) sent from the crankshaft sensor 8 and input to the engine ECU 60, corresponding to the reference tooth, second tooth, and first tooth, reaches a predetermined threshold is indicated as the first time. Subsequent times when the voltage of each output signal reaches the predetermined threshold are indicated as the second time, third time, and so on. The crank signal and other indicators are not shown in the figures for the periods from time t9 to time t10, from time t21 to time t22, and from time t33 to time t34. The energized states of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c are abbreviated as the energized states of the U-phase, V-phase, and W-phase. As mentioned above, the switching of the energized states of the U-phase, V-phase, and W-phase is done by correspondingly switching the on / off states of switching elements 131a and 131b, 131c and 131d, and 131e and 131f.

[0046] First, as shown in Figure 3 during the period labeled "first time," the control unit 132, at time t1, turns on the first timer and starts timing, and also starts supplying the high voltage of the U phase, when the first tooth signal, which is a crank signal generated corresponding to the first tooth portion 72c, reaches the threshold voltage for the first time. At time t2, when the timing of the first timer is completed, it starts supplying the high voltage of the V phase. At time t3, when the second tooth signal, which is a crank signal generated corresponding to the second tooth portion 72b, reaches the threshold voltage for the first time, the control unit 132 turns on the first timer and starts supplying the high voltage of the U phase. The IMA is turned on to start timing, and at time t4, when the timing of the second timer is completed, the supply of the high voltage of the W phase is started. At time t5, when the reference tooth signal, which is a crank signal generated in accordance with the reference tooth, reaches the threshold voltage for the first time, the control unit 132 applies this timing as the reference timing for controlling the operation of the motor 110, turns on the first timer to start timing, and switches the energized state of the U phase by ending the supply of the high voltage of the U phase and starting the supply of the low voltage of the U phase. Here, during the period from time t3 to time t5, the reference tooth signal has not yet reached the threshold voltage, and the stroke determination of the engine 1 is not yet complete, so the control unit 132 does not perform the switching of the energized state of each phase by ending the supply of the high voltage of the W phase (or the low voltage if it is the low side) from the U phase and starting the supply of the low voltage of the corresponding phase (or the high voltage if it is the high side). In the diagram, for convenience, the timers applied at times t1 and t5 are referred to as the same first timer, but the timers applied at these times may have different timing lengths. Also, the example shown is that the timing length of the second timer is set to half that of the first timer. Furthermore, even if the first tooth signal, the second tooth signal, and the reference tooth signal reach the threshold voltage from the second time onward, the motor control device 100 may be made to start an operation similar to the operation shown in Figure 3, so the first to fifth times shown in Figure 3 may be considered as the n (where n is a natural number) to n+4 times.

[0047] Next, as shown in Figure 3 during the second period, the control unit 132 switches the energization state of the V phase at time t6 by ending the supply of the high-side voltage of the V phase and starting the supply of the low-side voltage of the V phase as soon as the timing of the first timer is completed, turns on the second timer and starts timing when the tooth signal generated corresponding to the next tooth of the reference tooth reaches the threshold voltage, and at time t8 switches the energization state of the W phase by ending the supply of the high-side voltage of the W phase and starting the supply of the low-side voltage of the W phase as soon as the timing of the second timer is completed, and At time t9, when the tooth signal generated corresponding to the next tooth reaches the threshold voltage, the first timer is turned on to start timing, and the supply of the low voltage of the U phase is terminated and the supply of the high voltage of the U phase is started, thereby switching the energized state of the U phase. At time t10, when the first tooth signal reaches the threshold voltage for the second time, the first timer is turned on to start timing, and the supply of the high voltage of the U phase is terminated and the supply of the low voltage of the U phase is started, thereby switching the energized state of the U phase. At time t11, when the timing of the first timer is completed, the high voltage of the V phase is switched. The current state of the V phase is switched by ending the supply of the V phase low voltage and starting the supply of the V phase low voltage. At time t12, when the second tooth signal reaches the threshold voltage for the second time, the second timer is turned on and timing begins. At time t13, as the timing of the second timer is completed, the current state of the W phase is switched by ending the supply of the W phase high voltage and starting the supply of the W phase low voltage, and the third timer is turned on and timing begins. At time t14, as the timing of the third timer is completed, the supply of the U phase low voltage is ended and the supply of the U phase high voltage is started. This switches the energized state of the U phase, and the third timer is turned on again to start timing. At time t15, as soon as the timing of the third timer is completed, the supply of the low voltage of the V phase is terminated and the supply of the high voltage of the V phase is started, thereby switching the energized state of the V phase, and the third timer is turned on again to start timing. At time t16, as soon as the timing of the third timer is completed, the supply of the low voltage of the W phase is terminated and the supply of the high voltage of the W phase is started, thereby switching the energized state of the W phase. At time t17, when the reference tooth signal reaches the threshold voltage for the second time,This timing is applied as a reference timing for the control unit 132 to control the operation of the motor 110. At the same time, the first timer is turned on to start timing, and the supply of the high voltage to the U phase is terminated and the supply of the low voltage to the U phase is started, thereby switching the energized state of the U phase. Here, during the period from time t12, which is the timing when the second tooth signal reaches the threshold voltage for the second time, to time t17, which is the timing when the reference tooth signal reaches the threshold voltage for the second time, the crank signal does not reach the threshold voltage, and the stroke determination of engine 1 is not yet complete. However, based on the time interval between the timing when the first tooth signal, second tooth signal, and reference tooth signal reach the threshold voltage for the first time and the timing when the first tooth signal, second tooth signal, and reference tooth signal reach the threshold voltage for the second time, the control unit 132 sets one or both of the timing lengths of the second timer and the third timer and executes the timing, thereby ending the supply of low voltages for the U phase, V phase, and W phase and starting the supply of high voltages for these phases. Furthermore, depending on the circumstances, if the supply of the high voltage of the U phase is to be terminated at time t14, the supply of the low voltage of the U phase will be to Furthermore, when the control unit 132 sets either or both of the timing lengths of the second timer and the third timer, it reads and refers to data pre-stored in memory that defines the setting values ​​for either or both of the timing lengths of the second timer and the third timer for the time interval between the timing when the first tooth signal, second tooth signal, and reference tooth signal reach the threshold voltage for the first time and the timing when the first tooth signal, second tooth signal, and reference tooth signal reach the threshold voltage for the second time.

[0048] Next, as shown in Figure 3 for the period from the 3rd to the 5th time, the operations from time t17 to time t29, the operations from time t29 to time t41, and the operations from time t41 onward basically correspond to the operations from time t5 to time t17. However, at time t29, the stroke determination of engine 1 changes from an incomplete state to a completed state, so from time t29 onward, it becomes possible to execute operations based on the result of the stroke determination of engine 1. For example, in the period from time t36, when the second tooth signal reaches the threshold voltage for the third time, to time t41, when the reference tooth signal reaches the threshold voltage for the third time, the crank signal does not reach the threshold voltage. However, since the stroke determination of engine 1 is complete, based on the result of the stroke determination of engine 1, in other words, based on an accurate time interval between the second signal and the reference signal that reflects the stroke of engine 1, the time interval of the crank signal, and the temperature of engine 1 that affects friction, etc., the timing length of the second timer and the timing length of the third timer are set, or both are set, and the timing is executed, thereby ending the supply of the low voltages of the U, V, and W phases and starting the supply of the high voltages of these phases. For convenience, in the figure, the settings of the second and third timers in the period from time t36 to time t41 are shown as similar to those in the period from time t12 to time t17 and from time t24 to time t29. Furthermore, for example, in the period from time t36, which is the timing when the second tooth signal reaches the threshold voltage for the third time, to time t41, which is the timing when the reference tooth signal reaches the threshold voltage for the third time, when the control unit 132 sets one or both of the timing lengths of the second timer and the third timer, data that specifies the setting values ​​of one or both of the timing lengths of the second timer and the third timer based on the result of the engine 1's stroke determination is pre-stored in memory, and this data is read and referenced.

[0049] As described above, in the motor control device 100 of this embodiment, the control unit 132 sets the timing for switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c, based on a reference signal corresponding to a reference rotation angle that is set in advance as a reference rotation angle for the rotation angle of the crankshaft 7. Therefore, with a simplified configuration that omits a sensor for detecting the rotational position of the motor 110, the rotational position of the motor 110 around the rotation axis 112 can be determined from the rotation angle (rotational position) around the rotation axis of the crankshaft 7, and the rotational operation of the motor 110 can be appropriately controlled.

[0050] Furthermore, in the motor control device 100 of this embodiment, the control unit 132 sets the timing for switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c during the period from when the first signal, the second signal, and the reference signal are input in sequence for the nth time (where n is a natural number) until when the second signal is input for the (n+1)th time and the reference signal is input for the (n+1)th time. This allows for more appropriate control of the rotational operation of the motor 110.

[0051] Furthermore, in the motor control device 100 of this embodiment, the control unit 132 sets the timing for switching the energization state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c during the period from when the second signal is input for the (n+1)th time until the reference signal is input for the (n+1)th time, based on the timing when the second signal is input for the (n+1)th time. This allows for more appropriate control of the rotational operation of the motor 110.

[0052] Furthermore, in the motor control device 100 of this embodiment, it is preferable that the control unit 132 further determines the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the engine stroke, and sets the timing for switching the energized state of at least one of the currents flowing through the U-phase coil 110a, the V-phase coil 110b, and the W-phase coil 110c. In this case, the control unit 132 determines the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the engine stroke, based on the timing when the first signal, second signal, and reference signal are input in sequence for the nth time, the timing when the first signal, second signal, and reference signal are input in sequence for the (n+1)th time, and the timing when the first signal, second signal, and reference signal are input in sequence for the (n+2)th time. Therefore, the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 indicates the change in the engine's crank angle in time series, and considering that such an output signal corresponds to the engine stroke, the rotational operation of the motor 110 can be controlled more appropriately.

[0053] Furthermore, in the motor control device 100 of this embodiment, the control unit 132 further determines the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the stroke of the engine, based on the intake pressure of the engine 1 calculated based on the output signal sent from the intake pressure sensor 107, etc. Therefore, considering the intake pressure of the engine 1, which is closely related to the stroke of the engine 1, the relationship between the output signal sent from the crank angle sensor 8 corresponding to the position of the teeth 72 of the recurctor 70 and the stroke of the engine can be determined.

[0054] It should be noted that the present invention is not limited to the above-described embodiments in terms of the type, shape, arrangement, number, etc. of the components, and it is of course possible to modify them as appropriate without departing from the spirit of the invention, such as by appropriately substituting the components with those that produce equivalent effects. [Industrial applicability]

[0055] As described above, the present invention provides a motor control device that can appropriately control a motor with a simplified configuration that omits a sensor for detecting the rotational position of the motor, and is expected to be widely applicable to automobiles due to its general-purpose and universal nature. [Explanation of Symbols]

[0056] 1…Engine (internal combustion engine) 2…Cylinder block 3…Cooling water passage 4…Water temperature sensor 5... Piston 6…Connecting rod 7... Crankshaft 8... Crank angle sensor 9…Cylinder head 10… Combustion chamber 11... Spark plug 12…Intake passage 13…Intake valve 14…Fuel injector 15…Throttle valve 16… Exhaust passage 17… Exhaust valve 50…Engine control device 60…Engine ECU (Electronic Control Unit) 70... Relacta 72, 72a, 72b, 72c, 72d, 72e...teeth 72f... Missing tooth 100...Motor control device 101… Lead-acid battery 102... Load 105... Starter switch 106... Throttle position sensor 107... Intake pressure sensor 110... Generator-motor (motor) 110a... U-phase coil 110b...V-phase coil 110c...W phase coil 111a, 111b, 111c... connection terminals 112... Rotation axis 130…Motor ECU 131…AC (Alternate Current) / DC (Direct Current) Converter 131a, 131b... U-phase switching elements 131c, 131d... V-phase switching elements 131e, 131f...W-phase switching elements 132... Control Unit 133...Voltage receiving circuit EM... Exhaust pipe IM... Intake pipe

Claims

1. The control unit drives the motor that rotates the crankshaft of the internal combustion engine to start the internal combustion engine, while switching the energization state of each phase of the current supplied to the motor, A motor control device to which a signal corresponding to the rotation angle of the crankshaft is input, The motor control device is characterized in that the control unit sets the timing for switching the energized state of at least one of the phases based on a reference signal which is a signal corresponding to a reference rotation angle that serves as a reference for the rotation angle.

2. During one rotation of the crankshaft, a first signal different from the reference signal, a second signal different from the reference signal and the first signal, and the reference signal are generated in sequence. The interval between the second signal and the reference signal is longer than the interval between the first signal and the second signal. The motor control device according to claim 1, characterized in that the control unit sets the timing for switching the energization state during the period from when the second signal is input for the (n+1)th time until when the reference signal is input for the (n+1)th time, following the input of the first signal, the second signal, and the reference signal in order for the nth (n)th time each.

3. The motor control device according to claim 2, characterized in that the control unit sets the timing for switching the energized state during the period based on the timing when the second signal is input for the (n+1)th time.

4. The motor control device according to claim 1, further characterized in that the control unit sets the timing for switching the energization state based on the result of identifying the relationship between the signal and the stroke of the internal combustion engine.

5. The motor control device according to claim 4, characterized in that the control unit determines the relationship based on the timing when the first signal, the second signal, and the reference signal are input in order for the nth (n is a natural number) time, the timing when the first signal, the second signal, and the reference signal are input in order for the (n+1)th time, and the timing when the first signal, the second signal, and the reference signal are input in order for the (n+2)th time.

6. The motor control device according to claim 4 or 5, further characterized in that the control unit determines the relationship based on the intake pressure of the internal combustion engine.

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