JP5293218B2 - Vehicle motor control apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform optimum motor control even by a simple sensor. <P>SOLUTION: A motor control unit performs sensorless control to estimate a rotation angle of a motor without using a sensor and to control the motor when deciding that rotation of the motor 2 is in a steady state, obtains the rotation angle of the motor 2 based on a detection value of the sensor when deciding that the rotation of the motor 2 is in a transient varying state ("Yes" in one of step S1-step S3) or when deciding that the rotation of the motor 2 transits from the steady state to the transient varying state ("Yes" in one of step S4-step S5), and controls the motor 2 based on the obtained rotation angle of the motor 2 (step S6). <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a technique for controlling a motor of a hybrid vehicle.

  Patent Document 1 discloses that the rotation sensorless control and the rotation sensor control are switched according to the motor rotation speed. In the rotation sensorless control, the motor is controlled without detecting the motor rotation angle by the sensor. In the rotation sensor control, the motor is controlled based on the motor rotation angle detected by the sensor. Here, a crank angle sensor is used as the sensor.

Japanese Patent Laid-Open No. 9-219906

However, motor control (rotation sensor control) using a crank angle sensor as in Patent Document 1 has a problem that controllability is inferior to motor control using an advanced rotation sensor such as a resolver. On the other hand, if a resolver is used for motor control, since the resolver is a large sensor and expensive, the entire motor control system is increased in size and cost.
An object of the present invention is to optimally perform motor control even with a simple sensor.

In order to solve the above problems, the present invention determines that the rotation of the motor is in a transient fluctuation state when performing sensorless control for controlling the motor by estimating the rotation angle of the motor without using a sensor. When it is determined that the rotation of the motor transitions to the transient fluctuation state based on the operation of the driver, the control is switched to the motor control for controlling the motor based on the rotation angle of the motor obtained from the detected value of the sensor.

  According to the present invention, motor control can be performed optimally even with a simple sensor by switching between sensorless control and control using the detected value of the sensor in accordance with the rotational state of the motor.

It is a figure which shows the structure of the vehicle of 1st Embodiment. It is a figure for demonstrating the structure of the rotation sensor system of an engine. It is a block diagram showing composition of motor ECU etc. in a 1st embodiment. It is the figure used for description which calculates motor rotation angle (theta) based on the connection relation of the crank angle sensor and motor in a vehicle structure. It is a flowchart which shows the process sequence of the determination process of the motor rotation state determination part in 1st Embodiment. It is a characteristic view which shows the relationship between the wheel speed Vf of a front wheel, the wheel speed Vr (FIG. 6 (a)) of a rear wheel, and the state of a switch (FIG. 6 (b)). FIG. 8 is a characteristic diagram showing the relationship between the acceleration af (FIG. 7A) of the front wheels and the state of the switch (FIG. 7B). FIG. 9 is a characteristic diagram showing a relationship between acceleration (deceleration) af (FIG. 8A) of a front wheel and a switch state (FIG. 8B). It is a characteristic view which shows the relationship between accelerator opening ACC (FIG. 9 (a)) and the state of a switch (FIG.9 (b)). It is a characteristic view which shows the relationship between the state (FIG.10 (b)) of a brake, and the state (FIG.10 (c)) of a switch. It is a block diagram which shows structures, such as motor ECU in 2nd Embodiment. It is a flowchart which shows the process sequence of the determination process of the motor rotation state determination part in 2nd Embodiment. It is a block diagram which shows structures, such as motor ECU in 3rd Embodiment. It is a flowchart which shows the process sequence of the determination process of the motor rotation state determination part in 3rd Embodiment. It is a block diagram which shows structures, such as motor ECU in 4th Embodiment. It is a flowchart which shows the process sequence of the determination process of the motor rotation state determination part in 4th Embodiment.

A mode for carrying out the present invention will be described in detail with reference to the drawings.
(First embodiment)
The first embodiment is a motor control device to which the present invention is applied.
FIG. 1 shows a vehicle equipped with a motor control device. The vehicle shown in FIG. 1 is a configuration example of a parallel hybrid vehicle. As shown in FIG. 1, this vehicle has a motor 2 connected to an output shaft of an engine 1 that generates a driving force for driving directly or via a power transmission function such as a gear. In this embodiment, the engine 1 and the motor 2 are directly connected on the same axis, and the driving force of the engine 1 and the motor 2 is transmitted to the driving wheel (for example, front wheel) 5 through the transmission 4. This vehicle generates a driving assist force by the motor 2 using electric power from the high voltage battery 3. Furthermore, this vehicle charges the battery 3 with the regenerative power of the motor 2. The vehicle may be a vehicle in which the engine 1 and the motor 2 are gear-coupled.

  The vehicle includes an HEV (Hybrid Electric Vehicle) control system that controls the engine 1 and the motor 2, an engine control unit (engine ECU (Electronic Control Unit)) 11 as an engine control means, a transmission control unit (transmission ECU) 12, a motor It has a motor control unit (motor ECU) 30 as a control means, a battery management unit (battery ECU) 13, and a hybrid control unit (HEV_ECU) 14 that controls the entire HEV system. Each of the ECUs 11, 12, 13, 14, and 30 is configured around a microcomputer, and has various interfaces, peripheral circuits, and the like.

The vehicle also includes a crank angle sensor 6 that detects a crank angle of the engine 1 and a cam angle sensor 7 that detects a cam angle as sensors. Each sensor 6, 7 outputs a detection value to the engine ECU 11.
The vehicle also includes an accelerator opening sensor (or accelerator position sensor (APS)) 17, a wheel speed sensor 18, and a brake state sensor 19. The accelerator opening sensor 17 detects the amount of depression of the accelerator pedal. The wheel speed sensor 18 detects the wheel speed of a wheel (for example, the drive wheel 5). The brake state sensor 19 detects a brake state. Specifically, the brake state sensor 19 detects an operation state of a brake pedal (not shown). The brake state sensor 19 detects the operation state of the parking brake (PKB). Each sensor 17, 18, 19 outputs a detection value to the motor ECU 30. Further, the accelerator position sensor 17 outputs the detected value to the HEV_ECU 14.

The engine ECU 11 calculates parameters such as the throttle opening of the engine 1, the ignition timing, and the fuel injection amount. The engine ECU 11 outputs the calculated control signals for those parameters at a control timing determined based on information from the crank angle sensor 6 and the cam angle sensor 7 of the engine 1. Thereby, the engine ECU 11 controls the output of the engine 1.
The transmission ECU 12 controls the gear position of the transmission 4 according to a preset shift schedule.
The motor ECU 30 controls the motor 2 via the motor drive circuit 15. The motor ECU 30 controls the motor 2 using the number of rotations of the motor 2 detected by the sensor, or controls the motor 2 without a sensor, depending on the situation. The configuration of the motor ECU 30 will be described in detail later.

The motor 2 is a synchronous motor having a permanent magnet type rotor or a reluctance motor having a salient pole type rotor without a permanent magnet. The motor 2 is configured such that a three-phase stator coil that forms a rotating magnetic field is connected to the battery 3 from the motor drive circuit 15 via the high-voltage relay 16.
In the motor 2, the switching element for each phase of the motor drive circuit 15 is turned ON / OFF by a control signal from the motor ECU 30, and the rotor of the output shaft rotates by a current supplied from the battery 3 (normal power running operation). . The motor 2 operates as a generator that generates an electromotive force from the stator coil by forcibly rotating the rotor with an external force, and can charge the battery 3 (regenerative operation).

  The battery ECU 13 determines the battery state based on the remaining capacity indicated by the state of charge (SOC) of the battery 3, the input / output possible power amount indicated by the maximum input / output power in the battery 3, the deterioration degree of the battery 3, and the like. To grasp. The battery ECU 13 manages cooling and charging control of the battery 3, abnormality detection, protection operation at the time of abnormality detection, and the like based on the grasped battery state.

The HEV_ECU 14 obtains a required torque (vehicle driving torque requested by the driver) corresponding to the signal from the accelerator opening sensor 17. Further, the HEV_ECU 14 determines a distribution ratio between the torque shared by the engine 1 and the torque shared by the motor 2 with respect to the required torque. Then, HEV_ECU 14 outputs a control command according to the torque distribution ratio to engine ECU 11 and motor ECU 30. The HEV_ECU 14 controls opening and closing of the high-voltage relay 16 that opens and closes the power line between the battery 3 and the motor drive circuit 15.
In this vehicle, as indicated by broken lines in FIG. 1, the ECUs 11, 12, 13, 14, and 30 are connected via a communication line such as a CAN (Controller Area Network) so that bidirectional communication is possible. Thereby, each ECU11,12,13,14,30 is communicating mutually the control information and the sensing information regarding the operation state of a control object.

FIG. 2 is a diagram for explaining the configuration of the rotation sensor system of the engine 1.
As shown in FIG. 2, the engine 1 normally ignites and burns the air-fuel mixture in the combustion chamber 21 by the spark from the spark plug 22, and converts the reciprocating motion of the piston 23 accompanying the combustion into the rotational motion of the crankshaft 24. This is a spark ignition engine. In the engine 1, a crank rotor 25 for detecting a crank angle is attached to a crankshaft 24 that is an output shaft.
In the crank rotor 25, a plurality of detected portions are formed at predetermined intervals along the outer periphery thereof. The crank angle sensor 6 is disposed opposite to the detected portion of the crank rotor 25 at a predetermined interval. The crank angle sensor 6 is, for example, an electromagnetic pickup type sensor. The crank angle sensor 6 outputs a pulse train for each predetermined crank angle (for example, a pulse train for every 10 ° CA) to the engine ECU 11 as a crank angle signal by passing through the detected portion accompanying the rotation of the crank rotor 25.

  In addition, a camshaft 26 is disposed at the upper portion of the engine 1 to make a 1/2 turn with respect to the crankshaft 24 and open and close the intake and exhaust valves. A cam rotor 27 for cam angle detection is attached to the camshaft 26. In the cam rotor 27, a plurality of detected portions are formed at predetermined intervals along the outer periphery thereof. The cam angle sensor 7 is disposed opposite to the detected portion of the cam rotor 27 with a predetermined interval.

  The cam angle sensor 7 is an electromagnetic pickup type sensor, for example. The cam angle sensor 7 outputs, to the engine ECU 11, a pulse train having a predetermined timing with respect to the crank angle signal as a cam angle signal by the passage of the detected portion accompanying the rotation of the cam rotor 27. This cam angle signal becomes a pulse train including the compression top dead center of the specific cylinder (for example, a pulse train for every 0 ° CA and 120 ° CA of the # 1 cylinder). The engine ECU 11 uses a cam angle signal as a cylinder discrimination signal for discriminating a target cylinder for fuel injection or ignition.

FIG. 3 shows a specific configuration of the motor ECU (motor control unit) 30. Further, the motor drive circuit 15 shown in FIG. 1 corresponds to the inverter 15a shown in FIG.
As shown in FIG. 3, the motor ECU 30 includes a current command value calculator 31, subtractors 32a and 32b, PI calculators 33a and 33b, a three-phase converter 34, a PWM signal generator 35, a dq converter 36, and a motor rotation. An angle estimation unit 37, a switch 38, a motor rotation angle calculation unit 39, a motor rotation state determination unit 40, and a motor rotation speed calculation unit 41 are included.

Based on the torque command value Tm and the motor rotation speed Vm, the current command value calculation unit 31 determines the d-axis and q-axis current commands Id ^* and Iq ^* that will provide the highest efficiency at the current operating point. The torque command value Tm is an output value from the HEV_ECU 14. The motor rotation speed Vm is an output value from a motor rotation speed calculation unit 41 described later. For example, the current command value calculation unit 31 has a map, and the d-axis and q-axis current commands Id ^* and Iq ^* are determined based on the torque command value Tm and the motor rotation speed Vm with reference to the map. decide. Here, the d-axis current command Id ^* is a current command in the magnetic flux direction (d-axis) of the motor rotor. The q-axis current command Iq ^* is a current command in a direction (q-axis) orthogonal to the magnetic flux direction of the motor rotor. The current command value calculation unit 31 outputs the determined d-axis and q-axis current commands Id ^* and Iq ^* to the subtracters 32a and 32b.

The subtractor 32a calculates a deviation ΔId between the d-axis current command Id ^* and the current d-axis current Id. The subtractor 32b calculates a deviation ΔIq between the q-axis current command Iq ^* and the current q-axis current Iq. The subtractors 32a and 32b output the calculated deviations ΔId and ΔIq to the corresponding PI calculators 33a and 33b.
The PI calculator 33a calculates a d-axis voltage command Vd ^* by PI control calculation based on the input deviation ΔId. The PI calculator 33b calculates a q-axis voltage command Vq ^* by PI control calculation based on the input deviation ΔIq. The PI calculators 33 a and 33 b output the calculated d-axis and q-axis voltage commands Vd ^* and Vq ^* to the three-phase conversion unit 34 and the motor rotation angle estimation unit 37.

The three-phase conversion unit 34 performs coordinate conversion of the d-axis and q-axis voltage commands Vd ^* and Vq ^* from the d-axis and q-axis to the three axes U, V, and W, thereby converting the three-phase motor drive voltage commands Vu ^* , Vv ^* and Vw ^* are obtained. At this time, the three-phase conversion unit 34 performs coordinate conversion based on the motor rotation angle θ. The three-phase converter 34 outputs the motor drive voltage commands Vu ^* , Vv ^* , Vw ^* obtained by such conversion to the PWM signal generator 35.

The PWM signal generator 35 converts the motor drive voltage commands Vu ^* , Vv ^* , Vw ^* to obtain PWM control signals Pu, Pv, Pw for each phase. This conversion is performed, for example, by comparing the motor drive voltage commands Vu ^* , Vv ^* , Vw ^* with a triangular wave having a predetermined frequency and determining the duty ratio of the PWM control signal. The PWM signal generator 35 outputs the PWM control signals Pu, Pv, Pw obtained by such conversion to the inverter 15a (motor drive circuit 15).

  Inverter 15a receives the DC voltage from battery 3 between the positive electrode bus and the negative electrode bus, and converts this into a three-phase AC current. Specifically, the inverter 15a has a configuration in which three arms composed of two switching elements connected in series are connected between a positive electrode bus and a negative electrode bus, and the midpoint of each arm is a three-phase output. . Then, the two switching elements of each arm are complementarily turned on by the PWM control signals Pu, Pv, and Pw of each phase, so that a motor drive current is output to the motor 2 from the midpoint of each arm. The motor 2 is driven with an output corresponding to the output torque command when the motor driving current is supplied. For example, a capacitor for stabilizing the voltage is provided on the DC voltage input side from the battery 3 between the positive electrode bus and the negative electrode bus of the inverter 15a.

Output currents Iu, Iv, Iw of each phase from the inverter 15a are detected by current sensors 51u, 51v, 51w. The current sensors 51u, 51v, 51w output the detected output currents Iu, Iv, Iw to the dq converter 36.
The dq converter 36 converts the output currents Iu, Iv, and Iw to obtain d-axis and q-axis detection currents (current d-axis and q-axis currents) Id and Iq. At this time, the dq conversion unit 36 performs coordinate conversion based on the motor rotation angle θ. The dq conversion unit 36 outputs the d-axis and q-axis detection currents Id and Iq obtained by such conversion to the subtracters 32a and 32b and the motor rotation angle estimation unit 37.

The motor rotation angle estimation unit 37 is based on the d-axis and q-axis detection currents Id and Iq from the dq conversion unit 36 and the d-axis and q-axis voltage commands Vd ^* and Vq ^* from the PI calculators 33a and 33b. Estimate the rotation speed. The motor rotation angle estimation unit 37 outputs the estimated motor rotation angle (rotor position) θ to the first contact 38 a of the switch 38.
The switch 38 has a motor rotation angle calculator 39 connected to the second contact 38b. The switch 38 is configured to connect either the first contact 38a or the second contact 38b and the third contact 38c by switching. The output (motor rotation angle θ) of the third contact 38c is input to the three-phase conversion unit 34, the dq conversion unit 36, and the motor rotation speed calculation unit 41.
The motor rotation angle calculation unit 39 calculates (estimates) the motor rotation angle (rotor position) θ based on the detection value of the crank angle sensor 6. For example, the motor rotation angle calculation unit 39 calculates (estimates) the motor rotation angle θ based on the connection relationship between the crank angle sensor 6 and the motor 2 in the vehicle structure.

  Specifically, a crank angle sensor 6 is attached to a motor 2 that is directly connected to the engine 1 coaxially with a specific position as a reference. For example, when the motor 2 has a permanent magnet type rotor, as shown in FIG. 4A, a specific position of the crank angle sensor 6 (for example, 10 ° CA before compression top dead center of the # 1 cylinder), The reference position R is set together with the N-pole center of the permanent magnet 2 </ b> A disposed on the rotor of the motor 2. Then, the reference position R is used in common, and the detected position of the crank angle sensor 6 and the estimated rotational position of the motor 2 are matched. When the motor 2 has a salient pole type rotor without permanent magnets, as shown in FIG. 4B, a specific position of the crank angle sensor 6 (for example, 10 ° CA before compression top dead center of the # 1 cylinder). ) And the center of the salient pole portion 2B of the rotor of the motor 2 are used as a reference position R. Then, the reference position R is used in common, and the detected position of the crank angle sensor 6 and the estimated rotational position of the motor 2 are matched.

As a result, the rotational position information from the crank angle sensor 6 and the estimated rotational position information of the motor 2 can be made the same reference rotational information. Calculate (estimate) θ. The motor rotation angle calculation unit 39 outputs the calculated motor rotation angle θ to the second contact 38 b of the switch 38.
The motor rotation speed calculation unit 41 calculates a motor rotation speed Vm based on the motor rotation angle θ. Specifically, the motor rotation speed calculation unit 41 calculates the motor rotation speed Vm from the time change rate of the motor rotation angle θ. The motor rotation speed calculation unit 41 outputs the calculated motor rotation speed Vm to the current command value calculation unit 31.
The motor rotation state determination unit 40 controls the switching of the switch 38 based on the motor rotation state. Specifically, the motor rotation state determination unit 40 controls the switching of the switch 38 according to the motor rotation state estimated based on the detection values of the accelerator opening sensor 17, the wheel speed sensor 18, and the brake state sensor 19. .

  FIG. 5 shows a processing procedure of determination processing of the motor rotation state determination unit 40. As shown in FIG. 5, first, in step S <b> 1, the motor rotation state determination unit 40 determines that the wheel speed Vf of the front wheel (drive wheel 5) detected by the wheel speed sensor 17 is the wheel of the rear wheel detected by the wheel speed sensor 17. It is determined whether the speed Vr is greater than a predetermined value α. Here, the predetermined value α is an experimental value, an empirical value, or a theoretical value suitable for the determination process. When the wheel speed Vf of the front wheel is larger than the predetermined value α with respect to the wheel speed Vr of the rear wheel (Vf> Vr + α), the motor rotation state determination unit 40 determines that the rotation of the motor 2 is in a transient fluctuation state. Proceed to step S6. If not (Vf ≦ Vr + α), the motor rotation state determination unit 40 proceeds to step S2.

  The absolute value of the difference (Vf−Vr) between the wheel speed Vf of the front wheel (drive wheel 5) detected by the wheel speed sensor 17 and the wheel speed Vr of the rear wheel detected by the wheel speed sensor 17 is greater than a predetermined value α. It can also be determined whether or not it is large. In this case, when the absolute value of the difference (Vf−Vr) is larger than the predetermined value α (| Vf−Vr |> α), the motor rotation state determination unit 40 proceeds to step S6. If not (| Vf−Vr | ≦ α), the motor rotation state determination unit 40 proceeds to step S2.

  In step S2, the motor rotation state determination unit 40 calculates the acceleration (wheel speed acceleration) af of the front wheel (drive wheel 5) detected by the wheel speed sensor 17, and the calculated acceleration af is a predetermined value (threshold value) β. It is judged whether it is larger than. Here, the predetermined value β is an experimental value, an empirical value, or a theoretical value suitable for the determination process. When the front wheel acceleration af is larger than the predetermined value β (af> β), the motor rotation state determination unit 40 determines that the rotation of the motor 2 is in a transient fluctuation state, and proceeds to step S6. If not (af ≦ β), the motor rotation state determination unit 40 proceeds to step S3.

  In step S3, the motor rotation state determination unit 40 determines whether or not the acceleration (wheel speed acceleration) af of the front wheel (drive wheel 5) detected by the wheel speed sensor 17 is smaller than a predetermined value −β. That is, it is determined whether or not the absolute value of the deceleration of the wheel acceleration af is larger than the absolute value of the predetermined value β. When the front wheel acceleration af is larger than the predetermined value −β (af <−β), the motor rotation state determination unit 40 determines that the rotation of the motor 2 is in a transient fluctuation state, and proceeds to step S6. If not (af ≧ −β), the motor rotation state determination unit 40 proceeds to step S4.

  In step S4, the motor rotation state determination unit 40 determines whether or not the accelerator opening degree ACC detected by the accelerator opening degree sensor 17 is larger than a predetermined value (threshold value) ACCth. Here, the predetermined value ACCth is an experimental value, an empirical value, or a theoretical value suitable for the determination process. When the accelerator opening degree ACC is larger than the predetermined value ACCth (ACC> ACCth), the motor rotation state determination unit 40 proceeds to step S6. If not (ACC ≦ ACCth), the motor rotation state determination unit 40 proceeds to step S5.

In step S5, the motor rotation state determination unit 40 determines whether the brake pedal is turned on (operated) or the parking brake is turned on (operated) based on the detection result of the brake state sensor 19. . If at least one of the brake pedal and the parking brake is ON, the motor rotation state determination unit 40 proceeds to step S6. If not (the brake pedal and the parking brake are both OFF), the motor rotation state determination unit 40 determines that the rotation of the motor 2 is in a steady state and terminates the process shown in FIG.
In step S <b> 6, the motor rotation state determination unit 40 turns on the switch 38. Specifically, the motor rotation state determination unit 40 connects the second contact 38b and the third contact 38c. During normal operation (when the switch 38 is OFF), the first contact 38a and the third contact 38c are connected (in the switching state shown in FIG. 3).

(Operation and action)
The motor ECU 30 operates as follows by the determination process of the motor rotation state determination unit 40.
(1) FIG. 6 shows the relationship between the front wheel speed Vf and the rear wheel speed Vr (FIG. 6A) and the state of the switch 38 (FIG. 6B).
When the wheel speed Vf of the front wheel becomes larger than a predetermined value α with respect to the wheel speed Vr of the rear wheel as shown in FIG. 6A (Vf> Vr + α), the motor ECU 30 switches as shown in FIG. Set 38 to ON.

  Accordingly, the motor ECU 30 outputs the motor rotation angle θ calculated by the motor rotation angle calculation unit 39 based on the detection value of the crank angle sensor 6 to the three-phase conversion unit 34, the dq conversion unit 36, and the motor rotation speed calculation unit 41. To do. The three-phase conversion unit 34, the dq conversion unit 36, and the motor rotation speed calculation unit 41 perform various processes for driving and controlling the motor 2 based on the input motor rotation angle θ. That is, the motor ECU 30 performs motor control using the sensor.

Further, as shown in FIG. 6 (a), the motor ECU 30 shown in FIG. 6 (b) when the wheel speed Vf of the front wheel is not larger than a predetermined value α with respect to the wheel speed Vr of the rear wheel (Vf ≦ Vr + α). Thus, the switch 38 is turned off (maintains OFF).
Thus, the motor ECU 30 outputs the motor rotation angle θ estimated by the motor rotation angle estimation unit 37 to the three-phase conversion unit 34, the dq conversion unit 36, and the motor rotation speed calculation unit 41. The three-phase converter 34, the dq converter 36, and the motor rotation speed calculator 41 drive and control the motor 2 based on the input motor rotation angle θ (motor rotation angle θ estimated without using a sensor). Various processes are performed. That is, the motor ECU 30 performs sensorless motor control (sensorless control).

Here, when the wheel speed Vf of the front wheel is larger than the predetermined value α with respect to the wheel speed Vr of the rear wheel, there is a high possibility that the front wheel driven by the motor 2 is slipping. That is, there is a high possibility that the rotation of the motor 2 is in a transient fluctuation state. The motor ECU 30 performs motor control using the sensor under such circumstances.
As a result, when the rotation of the motor 2 is in a steady state, the motor control by the sensorless control is performed, and when the rotation of the motor 2 is in the transient fluctuation state, the motor control using the sensor can be performed. Motor control can be performed based on a proper motor rotation angle.

For example, in the sensorless control, the followability is poor when the motor rotation (motor rotation speed) is in a transient fluctuation state. Here, the reason why the followability deteriorates in the transient fluctuation state is that the parameter used when estimating the motor rotation angle in the transient fluctuation state deviates from the actual value. Even if the F / B gain is increased, it diverges, so that the gain cannot be increased. There is no example in which the current sensorless control is applied to an HEV drive motor.
Therefore, when the rotation of the motor 2 is in a transient fluctuation state, the motor control can be performed based on the appropriate motor rotation angle by switching to the motor control using the sensor. Control can be performed.

(2) FIG. 7 shows the relationship between the acceleration af (FIG. 7A) of the front wheels and the state of the switch 38 (FIG. 7B).
When the front wheel acceleration af becomes larger than a predetermined value β (af> β) as shown in FIG. 7A, the motor ECU 30 turns on the switch 38 as shown in FIG. 7B. That is, the motor ECU 30 performs motor control using the sensor.
When the front wheel acceleration af is equal to or less than a predetermined value β as shown in FIG. 7A, the motor ECU 30 switches 38 as shown in FIG. 7B when af ≦ β, where af ≧ −β. Is turned off (maintains OFF). That is, the motor ECU 30 performs sensorless motor control (sensorless control).

Here, when the acceleration af of the front wheels is larger than the predetermined value β, there is a high possibility that the front wheels driven by the motor 2 are slipping. That is, there is a high possibility that the rotation of the motor 2 is in a transient fluctuation state. The motor ECU 30 performs motor control using the sensor under such circumstances.
As a result, when the rotation of the motor 2 is in a steady state, the motor control by the sensorless control is performed, and when the rotation of the motor 2 is in the transient fluctuation state, the motor control using the sensor can be performed. Motor control can be performed based on a proper motor rotation angle. As a result, proper motor control can be performed even when the rotation of the motor 2 is in a transient fluctuation state.

(3) FIG. 8 shows the relationship between the acceleration (deceleration) af (FIG. 8A) of the front wheels and the state of the switch 38 (FIG. 8B).
When the front wheel acceleration (deceleration) af becomes smaller than a predetermined value −β (af <−β) as shown in FIG. 8A, the motor ECU 30 turns on the switch 38 as shown in FIG. 8B. To. That is, the motor ECU 30 performs motor control using the sensor.
8A, when the acceleration (deceleration) af of the front wheels is equal to or greater than a predetermined value −β (af ≧ −β, where af ≦ β), the motor ECU 30 returns to FIG. As shown, the switch 38 is turned OFF (OFF is maintained). That is, the motor ECU 30 performs sensorless motor control (sensorless control).

Here, when the acceleration (deceleration) af of the front wheels is smaller than the predetermined value −β, there is a possibility that the vehicle is suddenly stopped or the wheels are climbing on a curb. high. That is, there is a high possibility that the rotation of the motor 2 is in a transient fluctuation state. The motor ECU 30 performs motor control using the sensor under such circumstances.
As a result, when the rotation of the motor 2 is in a steady state, the motor control by the sensorless control is performed, and when the rotation of the motor 2 is in the transient fluctuation state, the motor control using the sensor can be performed. Motor control can be performed based on a proper motor rotation angle. As a result, proper motor control can be performed even when the rotation of the motor 2 is in a transient fluctuation state.

(4) FIG. 9 shows the relationship between the accelerator opening degree ACC (FIG. 9A) and the state of the switch 38 (FIG. 9B).
When the accelerator opening ACC is larger than a predetermined value ACCth (ACC> ACCth) as shown in FIG. 9A, the motor ECU 30 turns on the switch 38 as shown in FIG. 9B. That is, the motor ECU 30 performs motor control using the sensor.
Further, as shown in FIG. 9A, when the accelerator opening degree ACC is equal to or smaller than a predetermined value ACCth (ACC ≦ ACCth), the motor ECU 30 turns off the switch 38 as shown in FIG. maintain). That is, the motor ECU 30 performs sensorless motor control (sensorless control).

  Here, the case where the accelerator opening ACC is larger than the predetermined value ACCth is a case where rapid acceleration is performed. In this case, there is a high possibility that the rotation of the motor 2 transitions from the steady state to the transient fluctuation state because a large load is applied to the motor 2. That is, the rotation of the motor 2 is predicted to be in a transient fluctuation state. The motor ECU 30 performs motor control using the sensor under such circumstances.

  Thereby, when the rotation of the motor 2 is in a steady state, the motor control by the sensorless control is performed, and when the rotation of the motor 2 is predicted to be in a transient fluctuation state, the motor control using the sensor can be performed. Motor control can be performed based on an appropriate motor rotation angle. As a result, proper motor control can be performed even when the rotation of the motor 2 is in a transient fluctuation state.

(5) FIG. 10 shows the relationship between the state of the brake (brake pedal or parking brake) (FIG. 10B) and the state of the switch 38 (FIG. 10C).
When the brake is turned on as shown in FIG. 10 (b), the motor ECU 30 turns on the switch 38 as shown in FIG. 10 (c). That is, the motor ECU 30 performs motor control using the sensor.
Further, when the brake is OFF as shown in FIG. 10A, the motor ECU 30 turns off the switch 38 (maintains OFF) as shown in FIG. 10B. That is, the motor ECU 30 performs sensorless motor control (sensorless control).

  The motor ECU 30 can also control the switch 38 in consideration of the vehicle speed V as shown in FIG. Specifically, the motor ECU 30 assumes that the vehicle speed V is larger than a predetermined value (threshold value) Vth as shown in FIG. 10A, that is, the vehicle is cruising. As shown in FIG. 10 (b), the switch 38 is turned ON.

Here, the vehicle speed V is calculated based on the detection value of the wheel speed sensor 18. For example, the vehicle speed V is calculated based on the average value of the wheel speed of the driving wheel 5 and the wheel speed of the driven wheel obtained by the wheel speed sensor 18.
Here, the case where the brake (the brake pedal or the parking brake) is operated is a case where the vehicle is suddenly stopped. In this case, there is a high possibility that the rotation of the motor 2 transitions from the steady state to the transient fluctuation state because a large load is applied to the motor 2. That is, the rotation of the motor 2 is predicted to be in a transient fluctuation state. The motor ECU 30 performs motor control using the sensor under such circumstances.

  Thereby, when the rotation of the motor 2 is in a steady state, the motor control by the sensorless control is performed, and when the rotation of the motor 2 is predicted to be in a transient fluctuation state, the motor control using the sensor can be performed. Motor control can be performed based on an appropriate motor rotation angle. As a result, proper motor control can be performed even when the rotation of the motor 2 is in a transient fluctuation state.

As described above, it is possible to detect a sudden stop of the vehicle more appropriately by setting the switch 38 to be ON when the vehicle is traveling at a predetermined vehicle speed (the vehicle is cruising). it can.
Further, by setting the switch 38 to be ON when the brake operation speed, for example, the brake pedal depression speed is higher than a certain value, it is possible to detect a sudden stop of the vehicle more appropriately.

(Modification of the first embodiment)
When the motor control using the sensor is switched to the motor control based on the sensorless control, the threshold value used for the switching determination can be changed to a different value. Here, the threshold values used for switching determination are the predetermined values α, β, ACCth, and the like.

  In the first embodiment, the motor rotation state determination unit 40 realizes a motor rotation state determination unit that determines the rotation state of the motor. The crank angle sensor 6 realizes a crank angle detecting means for detecting the crank angle of the engine. Further, the configuration for calculating the command value of the motor 2 such as the current command value calculation unit 31, the three-phase conversion unit 34, the PWM signal generation unit 35, the dq conversion unit 36 and the motor rotation speed calculation unit 41 in the motor ECU 30 is as follows. A control means for sensorless control for controlling the motor by estimating the rotation angle of the motor without using a sensor is realized. In the first embodiment, when the motor rotation state determination unit determines that the rotation of the motor is in a transient fluctuation state, the control unit switches from the sensorless control to the motor control using the detection value of the sensor. In the motor control using the detection value of the sensor, the rotation angle of the motor is obtained based on the detection value of the crank angle detection means, and the rotation angle of the motor is obtained based on the obtained rotation angle of the motor. Realize controlling the motor.

  Moreover, in this 1st Embodiment, in the motor control method for vehicles which controls the motor which drives a wheel, the sensorless control which estimates the rotation angle of the said motor and controls the said motor is performed, without using a sensor. In this case, when it is determined that the rotation of the motor is in a transient fluctuation state, a vehicle motor control method for switching to motor control for controlling the motor based on the rotation angle of the motor obtained from the detection value of the sensor is realized. .

(Effects of the first embodiment)
(1) When the motor ECU 30 performs sensorless control for controlling the motor by estimating the rotation angle of the motor 2 without using a sensor, the motor ECU 30 determines that the rotation of the motor 2 is in a transient fluctuation state. The motor control is switched to control the motor based on the rotation angle of the motor obtained from the detected value.
Thus, by performing motor control by switching between sensorless control and motor control using the detection value of the sensor in conformity with the rotation state of the motor 2, the motor control can be optimally performed even with a simple sensor. That is, by switching between sensorless control and motor control using the sensor detection value in conformity with the rotation state of the motor 2, sensorless control and control using the sensor detection value can be performed in the optimum scene.
As a result, even a simple sensor can perform sensing with high accuracy and optimally perform motor control.

(2) When it is determined that the rotation of the motor 2 is in a steady state, the motor ECU 30 performs sensorless control.
Thereby, motor control can be performed by sensorless control in an optimal scene.
(3) When the absolute value of the wheel speed difference (Vf−Vr) between the front and rear wheels is larger than the predetermined value α (first threshold value), the motor rotation state determination unit 40 is in a transient fluctuation state. It is determined that
As a result, it can be determined that the rotation of the motor 2 is in a transient fluctuation state with high accuracy.

(4) The motor rotation state determination unit 40 determines that the rotation of the motor 2 is in a transient fluctuation state when the acceleration af of the wheel driven by the motor 2 is larger than a predetermined value β (second threshold value). .
As a result, it can be determined that the rotation of the motor 2 is in a transient fluctuation state with high accuracy.
(5) When the absolute value | af | of the deceleration of the wheel driven by the motor 2 is larger than the predetermined value β (third threshold value), the motor rotation state determination unit 40 causes the rotation of the motor 2 to change transiently. It is determined that it is in a state.
As a result, it can be determined that the rotation of the motor 2 is in a transient fluctuation state with high accuracy.

(6) The motor ECU 30 obtains the rotation angle of the motor 2 based on the detected value of the crank angle sensor 6 when the motor rotation state determination unit 40 determines that the rotation of the motor 2 transitions from the steady state to the transient fluctuation state. The motor is controlled based on the obtained rotation angle of the motor 2.
Thereby, the motor control using the detection value of the sensor and the sensorless motor control not using the sensor can be switched at an appropriate timing. As a result, the motor can be controlled appropriately by the control using the detection value of the sensor and the sensorless control.

(7) The accelerator opening sensor 17 for detecting the accelerator opening is provided. When the accelerator opening degree ACC detected by the accelerator opening degree sensor 17 is larger than a predetermined value ACCth (fourth threshold value), the motor rotation state determination unit 40 changes the rotation of the motor 2 from the steady state to the transient fluctuation state. Determine to transition.
Accordingly, it can be determined that the rotation of the motor 2 transitions from the steady state to the transient fluctuation state with high accuracy.

(8) A wheel speed sensor 18 serving as a vehicle traveling state detection unit that detects a vehicle traveling state, and a brake state sensor 19 serving as a brake operation state detecting unit that detects a brake operation state are provided. When the motor rotation state determination unit 40 detects a brake operation during vehicle traveling based on the detection results of the vehicle traveling state detection unit and the brake operation state detection unit, the rotation of the motor 2 changes from a steady state to a transient variation state. It is determined that the transition is made.
Accordingly, it can be determined that the rotation of the motor 2 transitions from the steady state to the transient fluctuation state with high accuracy.
(9) When the motor control using the sensor is switched to the motor control based on the sensorless control, the threshold value used for determining the switching is changed to a different value.
Thereby, hunting can be prevented and the motor control using the sensor can be returned to the motor control by the sensorless control.

(Second Embodiment)
The second embodiment is a motor control device to which the present invention is applied. The basic configuration of the vehicle in the second embodiment is the same as the configuration of the vehicle in the first embodiment shown in FIGS.
In the second embodiment, the motor rotation angle calculation unit 39 of the motor ECU 30 is based on the detected value of a wheel speed sensor (ABS (Anti-lock Brake System) sensor) 18 provided on the wheel axle. Is calculated (estimated).
FIG. 11 shows a specific configuration of the motor ECU 30 in the second embodiment. As shown in FIG. 11, in the second embodiment, the detection value of the wheel speed sensor 18 is output to the motor rotation angle calculation unit 39.

  The motor rotation angle calculation unit 39 calculates (estimates) the motor rotation angle θ based on the detection value of the wheel speed sensor 18. For example, when the motor 2 and the axle are directly or gear-coupled in the vehicle, the motor rotation angle calculation unit 39 calculates the motor rotation angle θ based on the connection relationship between the wheel speed sensor 18 and the motor 2 in the vehicle structure. Calculate (estimate). For example, the motor rotation angle θ is calculated (estimated) in consideration of the wheel diameter and the ratio of the gears interposed between the wheel speed sensor 18 and the motor 2. The motor rotation angle calculation unit 39 outputs the calculated motor rotation angle θ to the second contact 38 b of the switch 38.

  FIG. 12 shows a processing procedure of determination processing of the motor rotation state determination unit 40 in the second embodiment. As described above, when the motor rotation angle calculation unit 39 calculates the motor rotation angle θ based on the detection value of the wheel speed sensor 18, when the motor rotation state determination unit 40 turns on the switch 38 in step S6, the motor ECU 30 The motor control using the wheel speed sensor 18 is performed.

Details of the operation are the same as those in the first embodiment (see FIGS. 6 to 10).
In the second embodiment, the wheel speed sensor 18 realizes a wheel speed detecting means for detecting the wheel speed of the wheel. In the second embodiment, when the motor rotation state determination unit determines that the rotation of the motor is in a transient fluctuation state, the control unit switches from the sensorless control to the motor control using the detection value of the sensor. In the motor control using the detection value of the sensor, the rotation angle of the motor is obtained based on the detection value of the wheel speed detection means, and the rotation angle of the motor is obtained based on the obtained rotation angle of the motor. Realize controlling the motor.

(Effect of 2nd Embodiment)
(1) When the motor ECU 30 performs sensorless control for controlling the motor by estimating the rotation angle of the motor 2 without using a sensor, when determining that the rotation of the motor 2 is in a transient fluctuation state, Switching to motor control for controlling the motor 2 based on the rotation angle of the motor 2 obtained from the detection value of the speed sensor 18 is performed.
Thus, by performing motor control by switching between sensorless control and motor control using the detection value of the sensor in conformity with the rotation state of the motor 2, the motor control can be optimally performed even with a simple sensor.

(Third embodiment)
The third embodiment is a motor control device to which the present invention is applied. The basic configuration of the vehicle in the third embodiment is the same as the configuration of the vehicle in the first embodiment shown in FIGS.
In the third embodiment, the motor rotation angle calculation unit 39 of the motor ECU 30 calculates (estimates) the motor rotation angle θ based on the detection values of the crank angle sensor 6 and the wheel speed sensor 18.
FIG. 13 shows a specific configuration of the motor ECU 30 in the third embodiment. As shown in FIG. 13, in the third embodiment, the detection values of the crank angle sensor 6 and the wheel speed sensor 18 are output to the motor rotation angle calculation unit 39.

  The motor rotation angle calculation unit 39 calculates (estimates) the motor rotation angle θ based on the detection value of the crank angle sensor 6 (see the first embodiment). Further, the motor rotation angle calculation unit 39 calculates (estimates) the motor rotation angle θ based on the detection value of the wheel speed sensor 18 (see the second embodiment). Then, the motor rotation angle calculation unit 39 calculates an average value of the motor rotation angles θ calculated based on the detection values of the crank angle sensor 6 and the wheel speed sensor 18. The motor rotation angle calculation unit 39 outputs the calculated motor rotation angle θ to the second contact 38 b of the switch 38.

  FIG. 14 shows a processing procedure of determination processing of the motor rotation state determination unit 40 in the third embodiment. As described above, the motor rotation angle calculation unit 39 calculates the motor rotation angle θ (average value) based on the detection values of the crank angle sensor 6 and the wheel speed sensor 18, so that the motor rotation state determination unit 40 switches in step S6. When 38 is turned on, the motor ECU 30 performs motor control using the crank angle sensor 6 and the wheel speed sensor 18.

Details of the operation are the same as those in the first embodiment (see FIGS. 6 to 10).
In the third embodiment, when the motor rotation state determination unit determines that the rotation of the motor is in a transient fluctuation state, the control unit changes from the sensorless control to the motor control using the detection value of the sensor. In the motor control using the detection value of the sensor by switching, the rotation angle of the motor is obtained based on the detection values of the crank angle detection means and the wheel speed detection means, and the obtained motor The motor is controlled based on the rotation angle.

(Effect of the third embodiment)
(1) When the motor ECU 30 performs sensorless control for controlling the motor by estimating the rotation angle of the motor 2 without using a sensor, when the motor ECU 30 determines that the rotation of the motor 2 is in a transient fluctuation state, Switching to motor control for controlling the motor 2 based on the rotation angle of the motor 2 obtained from the detected values of the angle sensor 6 and the wheel speed sensor 18 is performed.
Thus, by performing motor control by switching between sensorless control and motor control using the detection value of the sensor in conformity with the rotation state of the motor 2, the motor control can be optimally performed even with a simple sensor.

(Fourth embodiment)
The fourth embodiment is a motor control device to which the present invention is applied. The basic configuration of the vehicle in the fourth embodiment is the same as the configuration of the vehicle in the first embodiment shown in FIGS.
In the fourth embodiment, the vehicle changes the rotation angle of the motor 2 in place of the crank angle sensor 6, the wheel speed sensor 18, and the motor rotation angle calculation unit 39 that the motor ECU 30 has in the first to third embodiments. It has a rotary encoder to detect.
FIG. 15 shows a specific configuration of the motor ECU 30 in the fourth embodiment. As shown in FIG. 15, in the fourth embodiment, the vehicle includes a rotary encoder 61 that detects the rotation angle of the motor 2. Then, the rotary encoder 61 outputs the detected motor rotation angle θ to the second contact 38b of the switch 38.

FIG. 16 shows a processing procedure of determination processing of the motor rotation state determination unit 40 in the fourth embodiment. As described above, as a result of outputting the detection value (motor rotation angle θ) of the rotary encoder 61 to the second contact 38b of the switch 38, when the motor rotation state determination unit 40 turns on the switch 38 in step S6, the motor ECU 30 Motor control using the rotary encoder 61 is performed.
Details of the operation are the same as those in the first embodiment (see FIGS. 6 to 10).

(Modification of the fourth embodiment)
In the fourth embodiment, motor control using a rotary encoder 61 is performed as motor control using a sensor. In contrast, the crank angle sensor 6 and the wheel speed sensor 18 as in the first to third embodiments are further provided, and the crank angle sensor 6, the wheel speed sensor 18, and the rotary are controlled as motor control using the sensors. Motor control using at least one of the encoders 61 can also be performed. In this case, the motor rotation angle obtained based on the detection value of the crank angle sensor 6, the motor rotation angle obtained based on the detection value of the wheel speed sensor 18, and the average value of the motor rotation angle obtained by the rotary encoder 61 are used. Perform motor control.

  In the fourth embodiment, the rotary encoder 61 realizes a rotary encoder that detects the rotation angle of the motor. In the fourth embodiment, when the motor rotation state determination unit determines that the rotation of the motor is in a transient fluctuation state, the control unit changes from the sensorless control to the motor control using the detection value of the sensor. In the motor control using the detection value of the sensor by switching, the rotation angle of the motor is determined based on the detection value of at least one of the crank angle detection means, the wheel speed detection means, and the rotary encoder. Thus, the motor is controlled based on the obtained rotation angle of the motor.

(Effect of the fourth embodiment)
(1) When the motor ECU 30 performs sensorless control for controlling the motor 2 by estimating the rotation angle of the motor 2 without using a sensor, when the motor ECU 30 determines that the rotation of the motor 2 is in a transient fluctuation state, The motor control is switched to control the motor 2 based on the rotation angle of the motor 2 obtained from the detection value of the rotary encoder 61.
Thus, by performing motor control by switching between sensorless control and motor control using the detection value of the sensor in conformity with the rotation state of the motor 2, the motor control can be optimally performed even with a simple sensor. As a result, the motor 2 can appropriately output the torque required from the vehicle.

(2) A rotary encoder 61 is used as a sensor.
As a result, the rotary encoder 61 is very small compared to the resolver, which is advantageous in terms of layout, and can reduce the size of the apparatus. Furthermore, since the rotary encoder 61 is very inexpensive compared to the resolver, it is advantageous in terms of cost merit, and the cost of the apparatus can be reduced.

  1 engine, 2 motor, 6 crank angle sensor, 17 accelerator opening sensor, 18 wheel speed sensor, 19 brake state sensor, 61 rotary encoder

Claims (7)

In a vehicle motor control apparatus for controlling a motor of a hybrid vehicle in which wheels are driven by an engine and a motor,
Motor rotation state determination means for determining the rotation state of the motor;
And at least one of a rotary encoder for detecting the rotation angle of the wheel speed detecting means and the motor for detecting the crank angle detecting means, the wheel speed of the front SL wheel for detecting the crank angle of the engine,
Control means for sensorless control for controlling the motor by estimating the rotation angle of the motor without using a sensor, and
When the motor rotation state determination unit determines that the rotation of the motor is in a transient fluctuation state, the control unit determines that the rotation of the motor is in a steady state based on a driver's operation. From the sensorless control to the motor control using the detection value of the sensor to control the motor,
The motor control using the detection value of the sensor, the crank angle detecting means, with the rotation angle of the motor based on detection detection value of the wheel speed detecting means or a rotary encoder, based on the rotation angle of the motor obtained the The motor control apparatus for vehicles characterized by controlling said motor. The motor rotation state determining means according to claim 1, wherein determining that the absolute value of the difference between the wheel speeds of the front and rear wheels is greater than the first threshold value, the rotation of the motor is in a transient state vehicle motor control system according to. The motor rotation state determining means, when the acceleration of the wheels driven by the said motor is greater than the second threshold value, according to claim 1 or rotation of the motor and judging to be in transient state vehicle motor control device according to 2. The motor rotation state determination means determines that the rotation of the motor is in a transient fluctuation state when an absolute value of deceleration of a wheel driven by the motor is larger than a third threshold value. The vehicle motor control device according to any one of claims 1 to 3 . Accelerator opening detection means for detecting the accelerator opening,
The motor rotation state determination means determines that the rotation of the motor transitions from a steady state to a transient fluctuation state when the accelerator opening detected by the accelerator opening detection means is larger than a fourth threshold value. The vehicle motor control device according to any one of claims 1 to 4 . Vehicle running state detecting means for detecting the vehicle running state; and brake operation state detecting means for detecting the brake operation state;
When the motor rotation state determination means detects a brake operation during vehicle running based on the detection results of the vehicle running state detection means and the brake operation state detection means, the rotation of the motor changes from a steady state to a transient fluctuation state. The vehicle motor control device according to claim 1, wherein the vehicle motor control device is determined to make a transition. In a vehicle motor control method for controlling a motor for driving wheels,
When performing sensorless control for controlling the motor by estimating the rotation angle of the motor without using a sensor, when it is determined that the rotation of the motor is in a transient fluctuation state , When the motor rotation is determined to transition to a transient fluctuation state based on the motor control method, the vehicle motor control method switches to motor control for controlling the motor based on the rotation angle of the motor obtained from the detection value of the sensor. .

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