Driving force control device for electric vehicle

A driving force control processor for an electric vehicle having a plurality of motors, which independently drive a plurality of wheels, and a plurality of inverters, which control a drive current for each of the motors in accordance with a driving force command value, the driving force control processor comprising:

• target driving force calculation means configured to calculate and output a target driving force for each of the motors in accordance with a vehicle operation performed by an operator of the vehicle or with the running status of the vehicle;
• determination means configured to receive the target driving force from the target driving force calculation means, and to determine and output whether the motors engaged in power running and in regeneration would coexist if each of the motors is driven by the target driving force;
• driving force command value calculation means configured to receive the output from the determination means, and if the determination means determines that the motors engaged in power running and in regeneration coexist, to adjust the distribution of driving force for each of the motors in accordance with the target driving force for each of the motors so that all the motors are engaged in either power running or regeneration, and to calculate an actual driving force command value for each of the motors;
• and
• command value output means configured to receive the actual driving force command value for each of the motors and to output the actual driving force command value to each of the inverters for the purpose of operating each of the motors,
• wherein the motors drive the left- and right-side wheels of the electric vehicle;
• and
• wherein, if the determination means determines that one of the two motors driving the left- and right-side wheels is engaged in power running whereas the other motor is engaged in regeneration, the driving force command value calculation means is configured to calculate the actual driving force command value for the motor engaged in regeneration by subtracting a value equivalent to the target driving force for the motor engaged in power running from the target driving force for the motor engaged in regeneration, and to calculate the actual driving force command value for the motor engaged in power running by changing the target driving force for the motor engaged in power running to zero.

A driving force control processor for an electric vehicle having a plurality of motors, which independently drive a plurality of wheels, a plurality of inverters, which control a drive current for each of the motors in accordance with a driving force command value, and a plurality of braking devices, which independently apply a braking torque to each of the wheels, the driving force control processor comprising:

• target driving force calculation means configured to calculate and output a target driving force for each of the motors in accordance with a vehicle operation performed by an occupant of the vehicle or with the running status of the vehicle;
• determination means configured to receive the target driving force from the target driving force calculation means, and to determine whether the motors engaged in power running and in regeneration would coexist if each of the motors is driven by the target driving force;
• driving force command value calculation means configured to receive the output from the determination means, and if the determination means determines that the motors engaged in power running and in regeneration coexist, to calculate the actual driving force command value for a motor engaged in power running in accordance with the target driving force for the motor engaged in power running, to calculate the actual driving force command value for a motor engaged in regeneration by changing the target driving force for the motor engaged in regeneration to zero, to calculate actual driving force command values for the braking devices in order to permit the braking devices to generate a braking torque equivalent to the target driving force for the motor engaged in regeneration, and to output the actual driving force command values;
• and
• command value output means configured to receive the actual driving force command values for the purpose of operating each of the motors and outputs the actual driving force command value to each of the inverters and to output the actual driving force command value to each of the braking devices.