Hybrid electric vehicle and method of controlling the same

A method of controlling a hybrid electric vehicle comprising an engine and a first motor connected to main drive wheels through a transmission and a second motor connected to auxiliary drive wheels, the method comprising:

• determining a required torque;
• in response to a predetermined condition being satisfied, determining a first torque that the second motor is to continuously output based on the required torque and a vehicle speed;
• in response to the predetermined condition being satisfied, determining a second torque that the second motor is to discontinuously output in order to compensate for acceleration loss in a situation in which the acceleration loss occurs due to a lack of an input torque to the transmission by the first motor or the engine based on a state of an engine clutch disposed between the engine and the first motor, a state of the transmission, or the required torque;
• determining an available output of the second motor;
• and
• determining a final torque of the second motor based on the first torque and the second torque, wherein determining the final torque is performed such that a sum of the first torque and the second torque does not exceed the available output.

A hybrid electric vehicle comprising:

• a transmission;
• an engine connected to main drive wheels through the transmission;
• a first motor connected to the main drive wheels through the transmission;
• a second motor connected to auxiliary drive wheels;
• in response to a predetermined condition being satisfied, a first controller configured to:
• determine a first torque that the second motor is to continuously output based on a required torque and a vehicle speed;
• determine a second torque that the second motor is to discontinuously output in order to compensate for acceleration loss in a situation in which the acceleration loss occurs due to a lack of a input torque to the transmission by the first motor or the engine based on a state of an engine clutch disposed between the engine and the first motor, a state of the transmission, or the required torque;
• and
• determine a final torque of the second motor based on the first torque and the second torque;
• and
• a second controller configured to control the second motor to output the final torque.