摘要 |
<p>In order to drive an electrically operated vehicle provided with an electric drive motor supplied with energy by a plurality of rechargeable batteries carried by the vehicle, in a manner to achieve high electric power utilization efficiency, the feed voltage for the driving motor is increased in steps by successive connection of a progressively increasing number of batteries in series with the driving motor, a load-dependent steady state of the motor corresponding to each feed voltage and to a constant rate of motor rotation, and the batteries are switched to provide a lower feed voltage when the motor, and thus also the vehicle, has achieved a selected steady state, at which time the driving motor, due to the dynamic inertia of the moving vehicle, acts as a generator which changes the batteries until the voltage generated by the motor acting as a generator drops to the lower feed voltage value, whereby a large portion of the energy used for propelling the vehicle is recovered.</p> |