Vehicle control systems, electric vehicles, and computer programs

Abstract

To provide a control device for a vehicle, capable of reducing a motor noise heard by an occupant.SOLUTION: A control device for a vehicle controls driving of an electric vehicle in which output torque from a drive motor is transmitted to a drive wheel via a transmission. When a vehicle speed of the electric vehicle is in a predetermined low vehicle speed region, the control device controls a revolution speed of the drive motor so that a frequency of a motor noise generated from the drive motor becomes less than a predetermined value, and controls a transmission ratio of the transmission so that drive torque transmitted to the drive wheel becomes equal to requested drive torque. When the vehicle speed of the electric vehicle is in a predetermined high vehicle speed region, the control device controls the revolution speed of the drive motor so that power efficiency of the drive motor becomes equal to or higher than predetermined efficiency, and controls the transmission ratio of the transmission so that the drive torque transmitted to the drive wheel becomes the requested drive torque.SELECTED DRAWING: Figure 4

Claims

1. In a vehicle control device for controlling the drive of an electric vehicle configured to transmit output torque from a drive motor to the drive wheels via a transmission, It comprises one or more processors and one or more memories connected to the one or more processors in a communicative manner, The aforementioned one or more processors When the vehicle speed of the electric vehicle is in a predetermined low-speed range, the rotational speed of the drive motor is reduced so that the frequency of the motor noise generated from the drive motor overlaps with the frequency band of the background noise generated while the electric vehicle is running, and the gear ratio of the transmission is controlled so that the drive torque transmitted to the drive wheels becomes the required drive torque. A vehicle control device that, when the vehicle speed of the electric vehicle is in a predetermined high-speed range, controls the rotational speed of the drive motor so that the power efficiency of the drive motor is equal to or greater than a predetermined efficiency, and controls the gear ratio of the transmission so that the drive torque transmitted to the drive wheels is equal to the required drive torque.

2. The aforementioned one or more processors The control device for a vehicle according to claim 1, wherein the rotational speed of the drive motor in the low vehicle speed region is set to a first value that is set in advance to be less than a predetermined rotational threshold at which the frequency of motor noise generated from the drive motor overlaps with the frequency band of background noise generated while the electric vehicle is running, and the rotational speed of the drive motor in the high vehicle speed region is set to a second value that is set in advance to be greater than or equal to a predetermined efficiency of the power efficiency of the drive motor.

3. In an electric vehicle configured to transmit output torque from a drive motor to the drive wheels via a transmission, When the vehicle speed of the electric vehicle is in a predetermined low-speed range, the rotational speed of the drive motor is controlled so that the frequency of the motor noise generated from the drive motor is below a predetermined rotational threshold that overlaps with the frequency band of the background noise generated while the electric vehicle is running, and the gear ratio of the transmission is controlled so that the drive torque transmitted to the drive wheels becomes the required drive torque. An electric vehicle equipped with a control device that, when the vehicle speed of the electric vehicle is in a predetermined high-speed range, controls the rotational speed of the drive motor so that the power efficiency of the drive motor is equal to or greater than a predetermined efficiency, and controls the gear ratio of the transmission so that the drive torque transmitted to the drive wheels is equal to the required drive torque.

4. In a computer program applied to a control device for an electric vehicle configured to transmit output torque from a drive motor to the drive wheels via a transmission, One or more processors, A process for determining whether the vehicle speed of the electric vehicle is in a predetermined low-speed range or a predetermined high-speed range, When the vehicle speed of the electric vehicle is in a predetermined low-speed range, the rotational speed of the drive motor is controlled to be below a predetermined rotational threshold in which the frequency of motor noise generated from the drive motor overlaps with the frequency band of background noise generated while the electric vehicle is running, and the gear ratio of the transmission is controlled so that the drive torque transmitted to the drive wheels becomes the required drive torque. When the vehicle speed of the electric vehicle is in a predetermined high-speed range, the process controls the rotational speed of the drive motor so that the power efficiency of the drive motor is equal to or greater than a predetermined efficiency, and controls the gear ratio of the transmission so that the drive torque transmitted to the drive wheels is equal to the required drive torque. A computer program that executes something.

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