Abstract: An electric bike includes a wheel driving apparatus. The wheel driving apparatus includes an electric wheel drive motor which drives a wheel, a gap changer which changes a gap length in the wheel drive motor, and a motor control unit which controls the wheel drive motor and the gap changer. The motor control unit calculates a target gap length for the gap changing motor in the gap changer based on an accelerator opening-degree signal, a rotation speed, a q-axis electric-current command value, a power source voltage, and a voltage utilization rate. Then, a feedback control is provided to the gap changer based on a difference value between the target gap length and the actual gap-length. A good vehicle characteristic is obtained without being affected by individual variability or operating environment of the electric motor through efficient drive of the electric motor from a low-speed range through a high-speed range.

Abstract: An electric bike includes a wheel driving apparatus. The wheel driving apparatus includes an electric wheel drive motor which drives a wheel, a gap changer which changes a gap length in the wheel drive motor, and a motor control unit which controls the wheel drive motor and the gap changer. The motor control unit calculates a target gap length for the gap changing motor in the gap changer based on an accelerator opening-degree signal, a rotation speed, a q-axis electric-current command value, a power source voltage, and a voltage utilization rate. Then, a feedback control is provided to the gap changer based on a difference value between the target gap length and the actual gap-length. A good vehicle characteristic is obtained without being affected by individual variability or operating environment of the electric motor through efficient drive of the electric motor from a low-speed range through a high-speed range.