JP7417185B2 - Torque difference adjustment system - Google Patents

Description

TECHNICAL FIELD This disclosure relates to a torque differential adjustment system.

Patent Document 1 discloses a vehicle control device that distributes driving force to each pair of wheels on the left and right sides of a vehicle in accordance with changes in the behavior of the vehicle. Such a vehicle control device includes first and second electric motors that are rotatably driven individually and have first and second output shafts, a first rotating element connected to the first output shaft, and other electric motors. A first differential device formed by second and third rotating elements; and a second differential device formed by the first rotating element and other second and third rotating elements connected to the second output shaft. a first output element formed by connecting a second rotational element of the first differential and a third rotational element of the second differential and connected to either one of the wheels; a second output element formed by connecting a third rotational element of the first differential and a second rotational element of the second differential and connected to the other of the wheels; and a body of the vehicle. a behavior change detection means for detecting a change in the behavior of the vehicle; a controller for calculating a target torque of each of the electric motors based on a detection result of the behavior change detection means and controlling each of the electric motors; Equipped with

Japanese Patent Application Publication No. 2008-215519

In the vehicle control device disclosed in Patent Document 1, an inertia torque that inhibits the vehicle body turning occurs when the vehicle body turns due to the configuration of the first differential device and the second differential device (power distribution device).

In view of the above-mentioned circumstances, it is an object of the present invention to provide a torque difference adjustment system capable of compensating for the inertia torque that occurs when a vehicle body turns due to the configuration of a power distribution device and inhibits the vehicle body turning.

A torque difference adjustment system according to at least one embodiment of the present invention is a torque difference adjustment system for adjusting a torque difference between a left wheel and a right wheel of a vehicle. a motor and a second motor different from the first motor, the power from the first motor is distributed to the left wheel and the right wheel, and the power from the second motor is distributed to the left wheel and the right wheel. a power distribution device that distributes the output torque of the first motor to the second motor; and a control device that controls the output torque of the first motor and the second motor; an inertia torque calculation unit that calculates a difference in inertia torque based on an input rotational speed and a rotational speed input from the second motor to the power distribution device; and the inertia calculated by the inertia torque calculation unit. an output torque calculation unit that calculates the output torque to be output from each of the first motor and the second motor based on the difference in torque; and an output torque calculation unit that calculates the output torque output from each of the first motor and the second motor, and The torque output unit includes a torque output unit that outputs an output to each of the motor and the second motor.

According to the above configuration, the inertia torque calculation unit calculates the difference in inertia torque based on the rotational speed input from the first motor to the power distribution device and the rotational speed input from the second motor to the power distribution device. The output torque calculation section calculates the output torque output from each of the first motor and the second motor based on the difference between the inertia torques calculated by the inertia torque calculation section. Then, the torque output section causes each of the first motor and the second motor to output the output torque calculated by the output torque calculation section from each of the first motor and the second motor. Thereby, the torque difference adjustment system can compensate for the inertia torque that occurs when the vehicle body turns due to the configuration of the power distribution device and inhibits the vehicle body turning.

In one embodiment of the present invention, the inertia torque calculation unit is configured to calculate the rotational speed input from the first motor to the power distribution device based on the speed of the left wheel and the speed of the right wheel. A rotational speed input from the motor to the power distribution device is calculated.

According to the above configuration, the inertia torque calculation unit calculates the rotation speed input from the first motor to the power distribution device and the rotation speed input from the second motor to the power distribution device based on the speed of the left wheel and the speed of the right wheel. The rotation speed can be calculated.

In one embodiment of the present invention, the inertia torque calculation unit calculates the rotational speed input from the first motor to the power distribution device based on the rotational speed of the first motor and the rotational speed of the second motor. and a rotational speed input from the second motor to the power distribution device.

According to the above configuration, the inertia torque calculation section calculates the rotational speed input from the first motor to the power distribution device and the second motor based on the rotational speed of the first motor and the rotational speed of the second motor. The rotational speed input from the motor to the power distribution device can be calculated.

In one embodiment of the present invention, a deceleration rate from the first motor to the power distribution device and a deceleration rate from the second motor to the power distribution device are respectively G, and the deceleration rate from the first motor to the power distribution device is G, If the reduction ratio applied from the first motor side to the left and right tires is b1, and the reduction ratio applied from the second motor side to the left and right tires in the power distribution device is b2, the output torque calculation section calculates the following: The difference (T _RI −T _LI ) between the right inertia torque and the left inertia torque is compensated based on Equation 1.

According to the above configuration, since the difference in inertia torque between the first motor and the second motor shown in the above equation 1 is compensated for, the difference between the first motor and the second motor that inhibits the vehicle body turning that occurs when the vehicle body turns is compensated. The inertia torque of the motor can be appropriately compensated.

In one embodiment of the present invention, the rotational speed is input from the first motor to the power distribution device and the rotation speed is input from the second motor to the power distribution device based on the operating state of the vehicle or the vehicle state. Calculate the rotation speed.

According to the above configuration, it is possible to calculate the rotation speed input from the first motor to the power distribution device and the rotation speed input from the second motor to the power distribution device based on the operation state of the vehicle or the vehicle state.

According to the torque difference adjustment system according to at least one embodiment of the present invention, it is possible to compensate for the inertia torque that occurs when the vehicle body turns due to the configuration of the power distribution device and inhibits the vehicle body turning.

1 is a conceptual diagram schematically showing the configuration of an electric vehicle equipped with a torque difference adjustment system according to an embodiment of the present invention. 1 is a diagram schematically showing a mechanical configuration of a torque difference adjustment system according to an embodiment of the present invention. FIG. 1 is a block diagram schematically showing a control configuration of a torque difference adjustment system according to an embodiment of the present invention. FIG. 3 is a characteristic line diagram showing input/output characteristics of the power distribution device shown in FIG. 2; 1 is a diagram schematically showing turning behavior of an electric vehicle equipped with a torque difference adjustment system according to an embodiment of the present invention. 1 is a diagram showing in detail the configuration of a power distribution device according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, and are merely illustrative examples. do not have.

The torque difference adjustment system 1 according to an embodiment of the present invention is an electric vehicle (EV), a hybrid vehicle (HV), or a plug-in hybrid vehicle (PHV, PHEV) that uses electricity charged in a driving battery 110 as a power source. ) etc. is mounted on an electric vehicle 100. The electric vehicle 100 equipped with the torque difference adjustment system 1 according to an embodiment of the present invention is a rear-drive electric vehicle in which two rear wheels are driven by a motor, but is not limited to this. It may be a four-wheel drive electric vehicle whose wheels are driven by a motor.

As shown in FIG. 1, a torque difference adjustment system 1 according to an embodiment of the present invention is a torque difference adjustment system for adjusting the torque difference between a left wheel 5L and a right wheel 5R of a vehicle. A first motor 11 serving as a power source, a second motor 12 different from the first motor 11, a power distribution device 3, and a control device 4 are provided.

The first motor 11 and the second motor 12 are motors with the same rated output and have the same motor inertia. The first motor 11 and the second motor 12 are, for example, AC motors, and a first inverter 21 is provided between the first motor 11 and the driving battery 110, and a first inverter 21 is provided between the first motor 11 and the driving battery 110. A second inverter 22 is provided between the battery 110 and the battery 110 . The first inverter 21 and the second inverter 22 convert the DC power charged in the driving battery 110 into AC power, and the output torque of the first motor 11 and the output torque of the second motor 12 are the same. can be adjusted arbitrarily.

As shown in FIG. 2, the power distribution device 3 according to the embodiment of the present invention distributes the power from the first motor 11 to the left wheel 5L and the right wheel 5R, and also distributes the power from the second motor 12. It is configured to be distributed to a left wheel 5L and a right wheel 5R. Here, the inertia of the left wheel axle 5L1 and the left tire (hereinafter referred to as "inertia of the left tire, etc.") is the same as the inertia of the right wheel axle 5R1 and the right tire (hereinafter referred to as "the inertia of the right tire, etc.").

As shown in FIG. 3, the control device 4 is configured to control the output torque of the first motor 11 and the second motor 12. The control device 4 includes, for example, an electric vehicle control device 40 (hereinafter referred to as "EV-ECU 40"), a first motor control device 41 (hereinafter referred to as "first MCU 41"), and a second motor control device 42 (hereinafter referred to as "first MCU 41"). (hereinafter referred to as "second MCU 42").

The EV-ECU 40 includes a processor (not shown) consisting of an arithmetic unit, registers for storing instructions and information, peripheral circuits, etc., and a memory (not shown) such as ROM (Read Only Memory) and RAM (Random Access Memory). ) and an input/output interface.

Information such as steering information (eg, steering angle), vehicle speed information (eg, wheel speed), accelerator pedal information (eg, amount of depression), and brake pedal information (eg, amount of depression) is input to the EV-ECU 40. The EV-ECU 40 is provided with, for example, an inertia torque calculation section 401, an output torque calculation section 402, and a torque output section 403.

The inertia torque calculation unit 401 calculates the difference in inertia torque based on the rotation speed input to the power distribution device 3 from the first motor 11 and the rotation speed input to the power distribution device 3 from the second motor 12. is configured to do so.

The inertia torque T _LIt of the left tire, etc., and the inertia torque T _RIt of the right tire, etc. can be expressed by the following equation 2.

Further, the inertia torque T _LIm of the first motor 11 on the axle and the inertia torque T _RIm of the second motor 12 on the axle can be expressed by Equation 3 below.

Therefore, the left inertia torque _TRI and the right inertia torque _TLI can be expressed by Equation 4 below.

As a result, the difference T _I between the right inertia torque T _RI and the left inertia torque T _LI can be expressed by Equation 5 below.

The output torque calculation unit 402 is configured to calculate the output torque of the first motor 11 and the output torque of the second motor 12 based on the difference in the inertia torque calculated by the inertia torque calculation unit 401.

Here, as shown in FIG. 4, the deceleration rate from the first motor 11 to the power distribution device 3 and the deceleration rate from the second motor 12 to the power distribution device 3 are G, respectively. If the deceleration rate from the first motor 11 side to the left and right wheel axles 5L1 is _b1 , and the deceleration rate from the second motor 12 side to the left and right wheel axles 5R1 is _b2 , then the axle torque T of the left wheel 5L The axle torque T _R of _{the L and} right wheels 5R can be expressed by Equation 6 below.

Therefore, the inertia torque T _LI of the left wheel 5L and the inertia torque T _RI of the right wheel 5R are as shown in Equation 7 below.

Thereby, the inertia torque is compensated by applying the opposite signs to the axle torque T _L of the left wheel 5L and the axle torque T _R of the right wheel 5R.

The torque output unit 403 is a unit that outputs the output torque of the first motor 11 and the output torque of the second motor 12 calculated by the output torque calculation unit 402, and the output torque of the first motor 11 is equal to the output torque of the first motor 11. The output torque of the second motor 12 is output to the MCU 41, and the output torque of the second motor 12 is output to the second MCU 42.

The first MCU 41 controls the first inverter 21 so that the first motor 11 outputs the output torque of the first motor 11 outputted from the torque output section 403, and the second MCU 42 controls the first inverter 21 so that the first motor 11 outputs the output torque of the first motor 11 outputted from the torque output section 403. The second inverter 22 is controlled so that the second motor 12 outputs the output torque of the second motor 12 output from the second motor 12 .

The torque difference adjustment system 1 according to the embodiment of the present invention described above is configured to adjust the rotation speed input from the first motor 11 to the power distribution device 3 and the rotation speed input from the second motor 12 to the power distribution device 3. The difference in inertia torque is calculated based on the difference in inertia torque, and the output torque of the first motor 11 and the output torque of the second motor 12 are calculated based on the difference in inertia torque. The output torque of the first motor 11 is output to the first MCU 41, and the output torque of the second motor 12 is output to the second MCU 42. The first MCU 41 controls the first inverter 21 so that the first motor 11 outputs the output torque of the first motor 11 output from the torque output unit 403, and the second MCU 42 controls the torque output The second inverter 22 is controlled so that the second motor 12 outputs the output torque of the second motor 12 output from the section 403. As a result, according to the torque difference adjustment system 1 according to the embodiment of the present invention, as shown in FIG. can.

In the torque difference adjustment system 1 according to the embodiment of the present invention, the inertia torque calculation unit 401A calculates the rotational speed input from the first motor 11 to the power distribution device 3 based on the rotational speed of the left wheel 5L and the right wheel 5R. The rotational speed input from the second motor 12 to the power distribution device 3 is calculated.

In this way, the inertia torque calculation unit 401A calculates the rotational speed input from the first motor 11 to the power distribution device 3 based on the rotational speed of the first motor 11 and the rotational speed of the second motor 12. The rotational speed input from the second motor 12 to the power distribution device can be calculated.

In the torque difference adjustment system 1 according to the embodiment of the present invention, the inertia torque calculation unit 401B moves the power distribution device 3 from the first motor 11 based on the rotational speeds of the first motor 11 and the second motor 12. The rotation speed input to the second motor 12 and the rotation speed input to the power distribution device 3 from the second motor 12 are calculated.

In this way, the inertia torque calculation unit 401B calculates the rotational speed input from the first motor 11 to the power distribution device 3 based on the rotational speed of the first motor 11 and the rotational speed of the second motor 12. The rotational speed input from the second motor 12 to the power distribution device 3 can be calculated.

The rotational angular acceleration of the first motor 11 and the rotational angular acceleration of the second motor 12 are determined by Equation 8 below.

Thus, for example, when the wheel speed sensor detects the rotational speeds ωL and ωR of the left wheel 5L and right wheel 5R when the vehicle turns, the rotational angular accelerations of the first motor 11 and the second motor 12 are determined. Similarly, for example, the rotational speeds ω _{Lm and ω Rm} of the first motor 11 and the second motor 12 when the vehicle turns are determined by resolvers (not shown) provided in the first motor 11 and the second motor ₁₂ . When detected, the rotational angular accelerations of the left wheel 5L and right wheel 5R are determined.

The inertia torque T _LIm of the first motor 11 and the inertia torque T _RIm of the second motor 12 are determined by Equation 9 below.

Then, T' _LIm and T' _RIm are determined by Equation 10.

Therefore, the inertia torques T _LIm and T _RIm of the motor are determined by Equation 11.

To put this in perspective, the inertia torques T _LIm and T _RIm of the motor are determined by Equation 12.

The difference between the inertia torque T _RIm of the second motor 12 and the inertia torque T _LIm of the first motor 11 is determined by Equation 13 below.

When the inertia torques of the left and right tires are added to Equation 13, the following Equation 14 is obtained.

In this way, since the difference in inertia torque between the first motor 11 and the second motor 12 shown in Equation 14 above is compensated for, the difference between the first motor 11 and the The inertia torque of the second motor can be appropriately compensated.

In one embodiment of the present invention, the rotation speed is input to the power distribution device 3 from the first motor 11 and the rotation speed is input to the power distribution device 3 from the second motor 12 based on the operating state of the vehicle or the vehicle-like body. Calculate the rotation speed.

According to the embodiment of the present invention described above, the rotational speed input from the first motor 11 to the power distribution device 3 and the input from the second motor 12 to the power distribution device are determined based on the operating state of the vehicle or the vehicle state. The rotation speed can be calculated.

In the torque difference adjustment system 1 according to the embodiment of the present invention, the inertia torque calculation unit 401C calculates the difference in inertia torque based on the operating state or vehicle state (for example, vehicle speed, steering angle) of the vehicle. It is configured.

The inertia torque calculation unit 401C calculates the difference in inertia torque from the center of gravity radius, outer wheel turning radius, inner wheel turning radius, slip angle, wheel speed, and the like.

As shown in FIG. 6, the power distribution device 3 according to one embodiment of the present invention includes a first reduction gear train 31, a second reduction gear train 32, and a differential gear train 33.

The first reduction gear train 31 includes an input gear 311, a counter gear 312, an output gear 313, and a differential drive gear 314. Input gear 311 is attached to the output shaft of first motor 11 , counter gear 312 meshes with input gear 311 , and power is transmitted from input gear 311 to counter gear 312 . An output gear 313 is provided coaxially with the counter gear 312, and the counter gear 312 and the output gear 313 rotate in the same direction and at the same speed. A drive gear meshes with the output gear 313, and power is transmitted from the output gear 313 to the differential drive gear 314.

Like the first reduction gear train 31, the second reduction gear train 32 includes an input gear 321, a counter gear 322, an output gear 323, and a differential drive gear 324. Input gear 321 is attached to the output shaft of second motor 12 , counter gear 322 meshes with input gear 321 , and power is transmitted from input gear 321 to counter gear 322 . An output gear 323 is provided coaxially with the counter gear 322, and the counter gear 322 and the output gear 323 rotate in the same direction and at the same speed. A drive gear meshes with the output gear 323, and power is transmitted from the output gear 323 to the differential drive gear 324.

The input gear 311, counter gear 312, output gear 313, and differential drive gear 314 of the first reduction gear train 31 and the input gear 321, counter gear 322, output gear 323, and differential drive gear of the second reduction gear train 32 324 are the same number of teeth, Z _i is the number of teeth of the input gears 311, 321, Z _c is the number of teeth of the counter gears 312, 322, Z o is the number of teeth of the output gears 313, 323, and Z _o is the number of teeth of the output gears 313, 323. , 324 is _Zd , the reduction ratio of the first reduction gear train 31 and the second reduction gear train 32 can be expressed by Equation 15 below.

The differential gear train 33 includes an input sun gear 331, an annulus gear 332, a large pinion gear 333, a carrier 334, a small pinion gear 335, and an output sun gear 336.

The input sun gear 331 is a gear that rotates together with the differential drive gear 314 that constitutes the first reduction gear train 31, and the power from the first motor 11 is transmitted to the input sun gear 331. The annulus gear 332 is an internal gear that rotates together with the differential drive gear that constitutes the second gear train, and the power from the second motor 12 is transmitted to the annulus gear 332 . Thereby, the input sun gear 331 and the annulus gear 332 become entrances to the differential gear train. Both the input sun gear 331 and the annulus gear 332 are meshed with a large pinion gear 333, and the large pinion gear 333 and the annulus gear 332 constitute a planetary gear that rotates around the input sun gear 331. The large pinion gear 333 is rotatably supported by the carrier 334, and the large pinion gear or the carrier 334 rotates due to the differential motion between the annulus gear 332 and the input sun gear 331. Further, a small pinion gear 335 is fixed to the carrier 334, and as the carrier 334 rotates, the small pinion gear 335 rotates around the output sun gear 336. An output sun gear 336 is meshed with the small pinion gear 335, and the small pinion gear 335 constitutes a planetary gear that rotates around the output sun gear 336. The rotation of the carrier 334 causes the right wheel axle 5R1 to rotate, and the rotation of the output sun gear 336 causes the left wheel axle 5L1 to rotate.

The number of teeth of input sun gear 331 is Z _S1 , the number of teeth of annulus gear 332 is Z _r1 , the number of teeth of large pinion gear 333 is Z _P1 , the number of teeth of small pinion gear 335 is Z _P2 and the number of teeth of output sun gear 336 is When Z _S2 , the reduction ratio b _{1 from the input sun gear 331 to the right wheel axle 5R1 and} the reduction ratio b ₂ from the annulus gear 332 to the left wheel axle can be expressed by Equation 16 below.

The present invention is not limited to the embodiments described above, and also includes forms in which modifications are added to the embodiments described above, and forms in which these forms are appropriately combined.

1 Torque difference adjustment system 11 First motor 12 Second motor 21 First inverter 22 Second inverter 3 Power distribution device 31 First reduction gear train 311 Input gear 312 Counter gear 313 Output gear 314 Differential drive gear 32 Second reduction gear train 321 Input gear 322 Counter gear 323 Output gear 324 Differential drive gear 33 Differential gear train 331 Input sun gear 332 Annulus gear 333 Large pinion gear 334 Carrier 335 Small pinion gear 336 Output sun gear 4 Control device 40 Electric vehicle control unit (EV-ECU)
401 Inertia torque calculation unit 402 Output torque calculation unit 403 Torque output unit 41 First motor control device (first MCU)
42 Second motor control device (second MCU)
5L Left wheel 5L1 Left wheel axle 5R Right wheel 5R1 Right wheel axle 100 Electric vehicle 110 Drive battery

Claims (5)

A torque difference adjustment system for adjusting a torque difference between a left wheel and a right wheel of a vehicle, the system comprising:
a first motor serving as a power source for the vehicle; and a second motor different from the first motor;
a power distribution device that distributes power from the first motor to the left wheel and the right wheel, and distributes power from the second motor to the left wheel and the right wheel;
a control device that controls the output torque of the first motor and the output torque of the second motor;
The control device includes:
an inertia torque calculation unit that calculates a difference in inertia torque based on a rotational speed input from the first motor to the power distribution device and a rotational speed input from the second motor to the power distribution device;
an output torque calculation unit that calculates an output torque to be output from each of the first motor and the second motor based on the difference in the inertia torque calculated by the inertia torque calculation unit;
a torque output section that causes each of the first motor and the second motor to output the output torque calculated by the output torque calculation section. The inertia torque calculation unit is
A rotation speed input from the first motor to the power distribution device and a rotation speed input from the second motor to the power distribution device are calculated based on the speed of the left wheel and the speed of the right wheel. The torque difference adjustment system according to claim 1. The inertia torque calculation unit is
The rotational speed input from the first motor to the power distribution device and the rotational speed input from the second motor to the power distribution device based on the rotational speed of the first motor and the rotational speed of the second motor. The torque difference adjustment system according to claim 1, which calculates a rotational speed. A deceleration rate from the first motor to the power distribution device and a deceleration rate from the second motor to the power distribution device are respectively G, and from the first motor side to the left and right tires in the power distribution device. When the reduction ratio applied is b1, and the reduction ratio applied from the second motor side to the left and right tires in the power distribution device is b2,
4. The torque difference adjustment system according to claim 2, wherein the output torque calculation unit compensates for a difference (T _RI - T _LI ) between a right inertia torque and a left inertia torque based on Equation 1 below.

The inertia torque calculation unit is
A rotation speed input from the first motor to the power distribution device and a rotation speed input from the second motor to the power distribution device are calculated based on an operating state of the vehicle or a vehicle state. The torque difference adjustment system according to any one of 1 to 4.

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