JP2017034785A - Motor drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor drive unit which can prevent that a driver feels incongruity when the driver of a vehicle which is mounted with the motor drive unit operates accelerator operation means.SOLUTION: This motor drive unit has an electric motor 5, a control device 6 and vehicle speed detection means 7. The control device 6 has an ECU 8 and a torque control part 11. Vehicle-speed correspondence torque control means 10 is interposed between the ECU 8 and the torque control part 11. The vehicle-speed correspondence torque control means 10 has an accelerator sensitivity adjustment part which adjusts a torque command value imparted to the torque control part 11 according to an operation amount so that current vehicle-speed correspondence maximum torque which is uniquely defined from vehicle-speed correspondence maximum torque which is changed by a vehicle speed reaches a maximum value of the torque command value which is imparted to the torque control part 11 from the vehicle-speed correspondence means 10 at a maximum operation amount of accelerator operation means 12, and that the torque command value is proportioned to the operation amount of the accelerator operation means 12.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motor drive device, and relates to a technique that can reduce a sense of discomfort to a driver of a vehicle equipped with the motor drive device.

  In an electric vehicle, generally, an accelerator opening is linearly converted into a torque command value, and an electric motor is driven via an inverter. However, the inverter side often performs control to limit the output of the electric motor. In this case, the output torque of the electric motor tends to decrease as the vehicle speed increases.

JP-A-6-54415

  When the output torque of the electric motor decreases as the vehicle speed increases, the torque command value for the accelerator opening exceeds the maximum output torque of the electric motor, which is an extra step that does not generate torque. . In this case, the driver of this electric vehicle is uncomfortable. As shown in FIG. 10, in the prior art, for example, when the accelerator pedal is depressed by a little more than half, the target torque may be reached at this time.

In FIG. 10, the display of “...%” Represents the ratio to the maximum depression amount (100%) of the accelerator pedal. When the vehicle speed exceeds the specified vehicle speed, the target torque is reached when the accelerator pedal is depressed at a predetermined ratio (90% to 50%) with respect to the maximum depression amount. For this reason, even if the driver further depresses the accelerator pedal, the actually generated torque does not increase.
As a result, the driver's intention is not reflected in the actual torque, and the drivability deteriorates. For this reason, there is a problem that the driver feels uncomfortable.

  An object of the present invention is to provide a motor drive device that can prevent a driver from feeling uncomfortable when a driver of a vehicle equipped with the motor drive device operates an accelerator operation means.

The motor drive device of the present invention has an electric motor 5 for driving the wheels 2 and 2, a control device 6 for controlling the electric motor 5, and a vehicle speed detecting means 7 for detecting the vehicle speed. A host controller 8 that receives a signal of an operation amount of the accelerator operating means 12 and outputs a drive command; and a torque controller 11 that torque-controls the electric motor 5 according to the drive command output from the host controller 8. A motor driving device having:
A vehicle speed corresponding torque control means 10 is interposed between the host control unit 8 and the torque control unit 11,
This vehicle speed corresponding torque control means 10
The current vehicle speed-corresponding maximum torque uniquely determined from the vehicle speed-corresponding maximum torque of the electric motor 5 that varies depending on the vehicle speed is given from the vehicle speed-corresponding torque control means 10 to the torque control unit 11 with the maximum operation amount of the accelerator operation means 12. An accelerator that adjusts the torque command value given to the torque control unit 11 according to the operation amount so that the torque command value is proportional to the operation amount of the accelerator operation means 12. It has the sensitivity adjustment part 10a. Here, being uniquely determined means that the curve of equal output is expressed as a hyperbola when the output is determined as the specification of the vehicle.

  According to this configuration, when the driver operates the accelerator operation unit 12, the upper control unit 8 receives a signal indicating the operation amount of the accelerator operation unit 12 and outputs a drive command. The accelerator sensitivity adjustment unit 10a of the vehicle speed corresponding torque control means 10 adjusts the torque command value given to the torque control unit 11 so as to satisfy all of the following conditions (1) and (2) according to the operation amount.

(1) The current vehicle speed-corresponding maximum torque uniquely determined from the vehicle speed-corresponding maximum torque of the electric motor 5 that varies depending on the vehicle speed is given from the vehicle speed-corresponding torque control means 10 to the torque control unit 11 with the maximum operation amount of the accelerator operation means 12. It becomes the maximum value of the torque command value.
(2) The torque command value is proportional to the operation amount of the accelerator operation means 12.

  Therefore, the vehicle speed corresponding torque control means 10 can give a torque command value corresponding to the operation amount of the accelerator operation means 12 to the torque control unit 11 during acceleration, for example. In this case, when the driver tries to operate the accelerator operation means 12 from, for example, an operation amount during acceleration to a maximum operation amount, the operation amount is reflected in the torque command value. Therefore, it is possible to improve drivability and prevent the driver from feeling uncomfortable.

When the vehicle speed detected by the vehicle speed detection means 7 exceeds a specified vehicle speed, the accelerator sensitivity adjustment unit 10a obtains a value obtained by dividing the output of the electric motor 5 calculated from the drive command and the vehicle speed by the current vehicle speed. The torque command value after adjustment may be used.
The specified vehicle speed is obtained by calculation from the maximum output and the maximum output torque of the electric motor 5, for example.
According to this configuration, when the vehicle speed exceeds the specified vehicle speed, a value obtained by dividing the motor output corresponding to the operation amount of the accelerator operation means 12 by the current vehicle speed is set as the adjusted torque command value. Even when the vehicle speed changes from moment to moment, the torque command value following the vehicle speed is accurately calculated as the adjusted torque command value.

When the vehicle speed detected by the vehicle speed detecting means 7 is equal to or less than a specified vehicle speed, the accelerator sensitivity adjusting unit 10a obtains a value obtained by dividing the output of the electric motor 5 calculated from the drive command and the vehicle speed by the specified vehicle speed. The torque command value after adjustment may be used.
In this case, the calculated motor output is divided by a constant specified vehicle speed to obtain the torque command value, so that the calculation processing load can be reduced when it is equal to or less than the specified vehicle speed.

  The accelerator sensitivity adjusting unit 10a may use the current maximum vehicle speed corresponding torque as the adjusted torque command value when the adjusted torque command value exceeds the current maximum vehicle speed corresponding torque. Also in this case, the calculation processing load can be reduced.

The accelerator sensitivity adjusting unit 10a may calculate the current maximum vehicle speed corresponding torque by using the relationship between the maximum vehicle speed corresponding torque and the maximum torque decreasing as the vehicle speed increases. Further, the relationship may be a relationship that provides a constant output according to the vehicle speed. Further, a relationship determined from the output characteristics of the inverter and the motor may be used. The relationship of the maximum torque corresponding to the vehicle speed may be determined by a result of a test or a simulation, for example.

  A motor drive device according to the present invention includes an electric motor that drives a wheel, a control device that controls the electric motor, and a vehicle speed detection unit that detects a vehicle speed, and the control device controls an operation amount of an accelerator operation unit. A motor drive device comprising: a host control unit that receives a signal and outputs a drive command; and a torque control unit that torque controls the electric motor according to the drive command output from the host control unit, wherein the host control unit and the torque A vehicle speed compatible torque control means is interposed between the controller and the vehicle speed compatible torque control means. The current vehicle speed compatible maximum torque uniquely determined from the vehicle speed compatible maximum torque of the electric motor, which changes according to the vehicle speed, is determined by the accelerator operation. The maximum operation amount of the means becomes the maximum value of the torque command value given from the vehicle speed corresponding torque control means to the torque control unit, and Wherein as the torque command value is proportional to the amount of operation of the cell operation means, having an accelerator sensitivity adjustment unit for adjusting a torque command value given to the torque controller in response to the operation amount. For this reason, when the driver | operator of the vehicle carrying this motor drive device operates an accelerator operation means, it can prevent giving a driver discomfort.

It is a block diagram of the conceptual composition which shows the electric vehicle carrying the motor drive concerning the embodiment of this invention with a top view. It is a block diagram of a control system of the motor drive device. It is a block diagram which shows each control part etc. of the motor drive device in detail. It is a figure which shows the relationship between the depression amount of the accelerator pedal of the same electric vehicle, and a torque command value. It is a figure which shows the relationship between the vehicle speed by the same motor drive device, and a torque command value. It is a flowchart which shows adjustment of the torque command value by the motor drive device. It is sectional drawing of the motor drive device which concerns on other embodiment of this invention. It is a figure which shows the example of the electric vehicle carrying the motor drive device which concerns on further another embodiment of this invention. It is a figure which shows the relationship between the vehicle speed and torque command value by the engine vehicle of a reference example. It is a figure which shows the relationship between the vehicle speed and torque command value of the electric vehicle of a prior art example.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a block diagram of a conceptual configuration showing, in plan view, an electric vehicle equipped with a motor drive device according to this embodiment. This electric vehicle is a four-wheeled vehicle in which the wheels 2 that are the left and right rear wheels of the vehicle body 1 are drive wheels and the wheels 3 that are the left and right front wheels are driven wheels. The front wheel 3 is a steering wheel. The wheels 3 and 3 which are the steering wheels as the left and right front wheels can be steered via a steering mechanism (not shown) and are steered by a steering means 4 such as a handle. In this example, the left and right wheels 2 and 2 serving as driving wheels are of a one-motor on-board type driven by a single electric motor 5 installed in the vehicle body 1. Each wheel 2 and 3 is provided with a brake (not shown). The motor drive device includes the electric motor 5, the control device 6, and vehicle speed detection means 7 (FIG. 2) for detecting the vehicle speed.

The control system will be described.
A control device 6 that controls the electric motor 5 is mounted on the vehicle body 1. The control device 6 includes an ECU 8 that is a host control unit and an inverter device 9. The inverter device 9 includes a vehicle speed corresponding torque control means 10 and a torque control unit 11. Between the ECU 8 and the torque control unit 11, a vehicle speed corresponding torque control means 10, which will be described later, is interposed. The ECU 8 performs overall control of the entire vehicle, and gives a drive command output from the ECU 8 to the vehicle speed corresponding torque control means 10. The ECU 8 includes a computer, a program executed on the computer, various electronic circuits, and the like.

  FIG. 2 is a block diagram of a control system of the motor drive device. As shown in FIGS. 1 and 2, the ECU 8 has a drive command generation unit 8a and a power running / regeneration control command unit 8b. The drive command generation unit 8a is provided with an acceleration command (power running) output from the accelerator operation means 12, a deceleration command (regeneration) output from the brake operation means 13 (see FIG. 1), and steering by the steering means 4 (see FIG. 1). From the turning command output by the steering angle sensor 4a for detecting the angle, an acceleration / deceleration command to be given to the electric motor 5 for traveling is generated as a drive command and output to the vehicle speed corresponding torque control means 10.

The power running / regenerative control command unit 8 b gives a command flag for switching between power running and regeneration to the vehicle speed corresponding torque control means 10.
The accelerator operation means 12 includes an accelerator pedal 12a and an accelerator sensor 12b that detects the amount of depression (operation amount) of the accelerator pedal 12a. The brake operation means 13 includes a brake pedal 13a and a brake sensor 13b that detects the amount of depression of the brake pedal 13a (see FIG. 1).

FIG. 3 is a block diagram showing in detail each control unit and the like of the motor drive device.
The torque control unit 11 torque-controls the electric motor 5 via the vehicle speed corresponding torque control means 10 in accordance with the drive command output from the drive command generation unit 8 a of the ECU 8. The torque control unit 11 includes a power circuit unit 14 provided for the electric motor 5 and a motor control unit 15 that controls the power circuit unit 14. The power circuit unit 14 includes an inverter (not shown) that converts the DC power of the battery 16 into three-phase AC power used for powering and regeneration of the electric motor 5, and a PWM driver (not shown) that controls the inverter. . The inverter is composed of a plurality of semiconductor switching elements, and the PWM driver performs pulse width modulation on the input current command and gives an on / off command to each of the semiconductor switching elements.

  The electric motor 5 is a three-phase synchronous motor. The electric motor 5 is provided with a rotation angle sensor 17 that detects a rotation angle as an electric angle of the motor rotor. The vehicle speed detection means 7 includes a rotation angle sensor 17 and a speed calculation means 18 in this example. The speed calculation means 18 can calculate the vehicle speed by differentiating the rotation angle detected by the rotation angle sensor 17.

  The motor control unit 15 includes a current PI control unit 19, a three-phase / two-phase conversion unit 20, and a two-phase / three-phase conversion unit 21. The motor control unit 15 includes a computer, a program executed on the computer, and an electronic circuit. The motor control unit 15 generates a command current to the electric motor 5 based on the adjusted torque command value given from the vehicle speed corresponding torque control means 10 and the command flag. When the power running control is selected by the command flag, the motor control unit 15 increases the power running command torque as the depression amount of the accelerator pedal 12a (FIG. 2) increases. When regenerative control is selected by the command flag, the motor control unit 15 increases the regenerative command torque as the amount of depression of the brake pedal 13a (FIG. 1) increases.

  The vehicle speed corresponding torque control means 10 includes an accelerator sensitivity adjustment unit 10a and a command current generation unit 10b. The accelerator sensitivity adjustment unit 10a adjusts the torque command value given to the torque control unit 11 so as to satisfy all of the following conditions (1) and (2) according to the depression amount of the accelerator pedal 12a (FIG. 2).

(1) The current vehicle speed-corresponding maximum torque uniquely determined from the vehicle speed-corresponding maximum torque of the electric motor 5 that changes depending on the vehicle speed is the maximum depression amount (maximum operation amount) of the accelerator pedal 12a. 11 is the maximum value of the torque command value given to 11.
(2) The torque command value is proportional to the depression amount of the accelerator pedal 12a (FIG. 2).

  FIG. 4 is a diagram showing the relationship between the accelerator pedal depression amount and the torque command value. Hereinafter, description will be given with reference to FIG. The depression amount, which is the operation amount of the accelerator pedal 12a (FIG. 2), and the torque command value are set in a proportional relationship. The accelerator sensitivity adjustment unit 10a (FIG. 3) sets the torque command value given to the torque control unit 11 (FIG. 3) so that the torque command value increases linearly as the depression amount of the accelerator pedal 12a (FIG. 2) increases. adjust.

  FIG. 5 is a diagram showing the relationship between the vehicle speed and the torque command value by this motor drive device. The accelerator sensitivity adjustment unit 10a (FIG. 3) may obtain the current vehicle speed-corresponding maximum torque by calculation using the relationship La of the vehicle speed-corresponding maximum torque where the maximum torque decreases as the vehicle speed increases. In this case, the relationship La of the maximum torque corresponding to the vehicle speed is stored in a rewritable manner in the storage means 22 (FIG. 3) provided in the inverter device 9, for example.

  According to the relationship La of the maximum torque corresponding to the vehicle speed, when the vehicle speed exceeds the specified vehicle speed, the maximum value of the torque command value decreases as the vehicle speed increases. However, regardless of the vehicle speed, the current maximum torque corresponding to the vehicle speed becomes the maximum value of the torque command value with the maximum depression amount of the accelerator pedal (100%: full stroke). That is, the maximum acceleration performance cannot be obtained unless the accelerator pedal is depressed to the maximum depression amount. When the accelerator pedal is loosened from the maximum depression amount (100%), the electric vehicle decelerates following the loosening ratio (for example, the maximum depression amount 100% to half depression amount 50%). According to the electric vehicle equipped with the motor drive device of the present embodiment, the acceleration / deceleration of the vehicle follows the amount of depression of the accelerator pedal, similarly to the engine vehicle of the following reference example.

  FIG. 9 is a diagram showing the relationship between the vehicle speed and the torque command value for the engine vehicle of the reference example. Also in the engine vehicle of the reference example, when the vehicle speed exceeds the specified vehicle speed, the maximum value of the torque command value decreases in proportion as the vehicle speed increases. Further, regardless of the vehicle speed, the current maximum torque corresponding to the vehicle speed becomes the maximum value of the torque command value at the maximum depression amount (100%) of the accelerator pedal. When the accelerator pedal is loosened from the maximum depression amount (100%), the vehicle decelerates following the loosening rate.

As shown in FIG. 3, the accelerator sensitivity adjustment unit 10a adjusts the torque command value according to the depression amount of the accelerator pedal 12a (FIG. 2). The torque command value in this case is adjusted as follows.
First, a formula for calculating the output (W) of the electric motor 5 is shown in Formula (1).
W = ω × T Equation (1)
Where ω: vehicle speed, T: torque command value (before adjustment)
The torque command value (before adjustment) (T) is obtained in accordance with a predetermined relationship with respect to the drive command given from the drive command generation unit 8a. The defined relationship is determined by the result of a test or simulation, for example.

After calculating the output (W) of the electric motor 5 as described above, the accelerator sensitivity adjustment unit 10a determines whether or not the current vehicle speed exceeds a specified vehicle speed (ω0: for example, several tens of km / h). The specified vehicle speed (ω0) is obtained by dividing the maximum output (W0) of the electric motor 5 by the maximum output torque (T0). When it is determined that the current vehicle speed exceeds the specified vehicle speed, the accelerator sensitivity adjustment unit 10a calculates a value (W / ω) obtained by dividing the output (W) of the electric motor 5 by the current vehicle speed (ω), and the adjusted torque. The command value is T ^* . Thereby, even when the vehicle speed changes from moment to moment, the torque command value that follows the vehicle speed is accurately calculated as the adjusted torque command value.

When it is determined that the current vehicle speed is less than or equal to the specified vehicle speed, the accelerator sensitivity adjustment unit 10a determines the value (W / ω0) obtained by dividing the output (W) of the electric motor 5 by the specified vehicle speed (ω0) as the adjusted torque. The command value is T ^* . Thereby, it is possible to reduce the calculation processing load when the vehicle speed is equal to or lower than the specified vehicle speed.
However, when the adjusted torque command value T ^* exceeds the current maximum vehicle speed corresponding torque (T0), the accelerator sensitivity adjusting unit 10a adjusts the current maximum vehicle speed corresponding torque (T0) to the adjusted torque command value T. ^*

The command current generator 10b generates a primary current (Ia) and a current advance angle (β) of the electric motor 5 based on the adjusted torque command value T ^* . Further, the command current generation unit 10b is based on the values of the primary current (Ia) and the current advance angle (β), and the d-axis current (field component) Id ^* and the q-axis current (torque component) Iq ^* . One command current is generated.

The current PI control unit 19 is a three-phase / two-phase conversion unit 20 based on the values of the d-axis current Id ^* and the q-axis current Iq ^* output from the command current generation unit 10b and the motor current and the rotor angle of the electric motor. From the calculated two-phase currents Id and Iq, control amounts Vdc and Vqc based on voltage values by PI control are calculated. In the three-phase / two-phase conversion unit 20, the following formula Iv = − (Iu + Iw) is obtained from the detected values of the u-phase current (Iu) and the w-phase current (Iw) of the electric motor 5 detected by the current sensor 23. The v-phase current (Iv) is calculated. The three-phase / two-phase converter 20 converts the three-phase currents of Iu, Iv, and Iw into the two-phase currents of Id and Iq.

  The rotor angle of the electric motor 5 used for this conversion is acquired from the rotation angle sensor 17. The two-phase / three-phase conversion unit 21 converts the input two-phase control amounts Vdc, Vqc and the rotor angle acquired from the rotation angle sensor 17 into three-phase PWM duties Vu, Vv, Vw. The power circuit unit 14 performs PWM control of the inverter according to the PWM duties Vu, Vv, and Vw, and drives the electric motor 5.

FIG. 6 is a flowchart showing adjustment of the torque command value by the motor drive device.
After the start of this process, the accelerator sensitivity adjustment unit 10a of the vehicle speed corresponding torque control means 10 acquires the maximum output (W0: for example, several tens of kW) and the maximum output torque (T0) of the electric motor 5 (step S1). These maximum output (W0) and maximum output torque (T0) are rated values specific to the electric motor, and are stored in the storage means 22 and read out as necessary.

  Next, the accelerator sensitivity adjustment unit 10a calculates a specified vehicle speed (ω0) (step S2). The specified vehicle speed (ω0) is obtained by dividing the maximum output (W0) of the electric motor 5 by the maximum output torque (T0). Next, the accelerator sensitivity adjustment unit 10a detects the depression amount (accelerator signal A) of the accelerator pedal 12a from the accelerator sensor 12b (step S3). Next, the accelerator sensitivity adjustment part 10a acquires a vehicle speed from the vehicle speed detection means 7 (step S4).

Next, the accelerator sensitivity adjustment unit 10a calculates the output of the electric motor 5 (step S5). Thereafter, the accelerator sensitivity adjustment unit 10a determines whether or not the current vehicle speed (ω) exceeds the specified vehicle speed (ω0) (step S6). When it is determined that the current vehicle speed (ω) exceeds the specified vehicle speed (ω0) (step S6: Yes), the accelerator sensitivity adjustment unit 10a is a value obtained by dividing the output of the electric motor 5 by the current vehicle speed (W / ω). Is the adjusted torque command value T ^* (step S7).

When it is determined that the current vehicle speed (ω) is equal to or lower than the specified vehicle speed (step S6: No), the accelerator sensitivity adjustment unit 10a adjusts a value (W / ω0) obtained by dividing the output of the electric motor 5 by the specified vehicle speed. The subsequent torque command value T ^* is set (step S8). However, in step S8, when the adjusted torque command value T ^* exceeds the current vehicle speed corresponding maximum torque (T0), the accelerator sensitivity adjustment unit 10a adjusts the current vehicle speed corresponding maximum torque (T0). The command value is T ^* . Thereafter, this process is terminated.

  According to the motor drive device described above, the vehicle speed corresponding torque control means 10 can give a torque command value corresponding to the depression amount of the accelerator pedal 12a to the torque control unit 11 during acceleration, for example. In this case, when the driver tries to operate the accelerator pedal 12a from, for example, a depression amount during acceleration to a maximum depression amount, the depression amount is reflected in the torque command value. When the accelerator pedal 12a is loosened from the maximum depression amount, the electric vehicle decelerates following the loosening rate. Thus, the acceleration / deceleration of the vehicle follows the amount of depression of the accelerator pedal 12a. Therefore, it is possible to improve drivability and prevent the driver from feeling uncomfortable.

Another embodiment will be described.
In the following description, the same reference numerals are assigned to the portions corresponding to the matters described in the preceding forms in each embodiment, and overlapping descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in advance unless otherwise specified. The same effect is obtained from the same configuration. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

  As shown in FIG. 7, the electric motor 5 may constitute an in-wheel motor drive device IWM. In this case, the left and right wheels 2 and 2 (FIG. 1) serving as driving wheels are driven by independent electric motors 5 respectively. Each in-wheel motor drive device IWM has the electric motor 5, the reduction gear 24, and the wheel bearing 25, respectively, These are arrange | positioned in part or the whole in a wheel. The rotation of the electric motor 5 is transmitted to the drive wheel 2 via the speed reducer 24 and the wheel bearing 25.

  A brake rotor 26 constituting a brake is fixed to the flange portion of the hub wheel 25 a of the wheel bearing 25, and the brake rotor 26 rotates integrally with the drive wheel 2. The electric motor 5 is, for example, an embedded magnet type synchronous motor in which a permanent magnet is built in the core portion of the rotor 5a. The electric motor 5 is a motor in which a radial gap is provided between the stator 5 b fixed to the housing 27 and the rotor 5 a attached to the rotation output shaft 28.

  The in-wheel motor drive unit IWM is a so-called direct motor type in which a cycloid reduction gear, a planetary reduction gear, a parallel two-axis reduction gear, and other reduction gears can be applied. Also good.

As shown in FIG. 8, the vehicle may be a two-motor on-board type in which the left and right rear wheels 2 and 2 are independently driven by two electric motors 5 and 5 provided on the vehicle body 1.
As the vehicle, a front-wheel drive type electric vehicle that drives the left and right front wheels in a 1-motor on-board format, a 2-motor on-board format, or an in-wheel motor drive format may be applied. In each of the above types, a four-wheel drive electric vehicle that drives the front, rear, left, and right wheels may be applied.

  As mentioned above, although the form for implementing this invention based on embodiment was demonstrated, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

2 ... wheel 5 ... electric motor 6 ... control device 7 ... vehicle speed detection means 8 ... ECU (upper control unit)
DESCRIPTION OF SYMBOLS 10 ... Vehicle speed corresponding torque control means 10a ... Accelerator sensitivity adjustment part 11 ... Torque control part 12 ... Accelerator operation means

Claims (5)

An electric motor for driving the wheels, a control device for controlling the electric motor, and a vehicle speed detection means for detecting the vehicle speed. The control device outputs a drive command in response to an operation amount signal of the accelerator operation means. In a motor drive device having a high-order control unit and a torque control unit for torque-controlling the electric motor according to a drive command output from the high-order control unit,
A vehicle speed corresponding torque control means is interposed between the upper control unit and the torque control unit,
This vehicle speed compatible torque control means
The current vehicle speed-corresponding maximum torque uniquely determined from the vehicle speed-corresponding maximum torque of the electric motor that changes according to the vehicle speed is a torque command value that is given from the vehicle speed-corresponding torque control means to the torque control unit with the maximum operation amount of the accelerator operation means. And an accelerator sensitivity adjustment unit that adjusts a torque command value given to the torque control unit according to the operation amount so that the torque command value is proportional to the operation amount of the accelerator operation means. The motor drive device characterized by this.   2. The motor drive device according to claim 1, wherein when the vehicle speed detected by the vehicle speed detection means exceeds a specified vehicle speed, the accelerator sensitivity adjustment unit outputs an output of the electric motor calculated from the drive command and the vehicle speed. The motor drive device which uses the value divided by the vehicle speed as the torque command value after adjustment.   3. The motor drive device according to claim 1, wherein the accelerator sensitivity adjustment unit calculates the electric motor calculated from the drive command and the vehicle speed when a vehicle speed detected by the vehicle speed detection unit is equal to or lower than a specified vehicle speed. A motor drive device in which a value obtained by dividing the output of the vehicle by the specified vehicle speed is used as an adjusted torque command value.   4. The motor drive device according to claim 3, wherein when the adjusted torque command value exceeds the current maximum vehicle speed corresponding torque, the accelerator sensitivity adjustment unit adjusts the current maximum vehicle speed corresponding torque command. Motor drive device to be value.   The motor drive device according to any one of claims 1 to 4, wherein the accelerator sensitivity adjustment unit uses a vehicle speed corresponding maximum torque approximation curve in which the maximum torque decreases in proportion as the vehicle speed increases. A motor drive device for obtaining the current maximum vehicle speed torque by calculation.

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