2011

Development of “One Motor Type Electric Vehicle (EV) Drive System”March 25, 2011

NTN Corporation (hereafter, NTN) has developed the world's first “One motor type electric vehicle (EV) drive system” with an automatic transmission, which contributes to the weight reduction and high efficiency of one motor type electric vehicles^*1 (hereafter, one motor EV).

The drive systems of common one motor EV use a reduction gear without a transmission function; therefore, large drive motors were used in order for the acceleration performance at low speeds, and the rotating performance while running at high speeds to be compatible. For this reason, sufficient installation space was also required.

The “One motor type EV drive system” developed by NTN, consists of a compact and lightweight drive motor, differential^*2 and inverter, using a new two-speed automatic transmission which is an alternative to the conventional fixed type transmission. The two-speed automatic transmission mechanism was developed as the transmission mechanism using a unique actuator for shifting. Accordingly, the high speed and compact motor could be used at a high efficiency in a wide range of EV driving conditions. This system has realized both smooth acceleration performance from low speeds and high speed running performance, and the overall drive system became compact with reduced weight.

NTN will offer this system as the “NTN-one motor type EV power train” by adding a constant-velocity joint, Multi Axis Load Sensor Integrated Hub Bearing and etc., which are the main products of NTN to the one motor type EV drive system.

*1 An EV in which an electric motor is used in a conventional internal combustion engine vehicle, instead of an engine.
Since numerous conventional technologies, such as vehicle body technology and production technology can be used as is, this method is mainly used for current EV.

*2 The differential is a transmission system which is used in any vehicle with wheels, such as automobiles, and distributes and transmits the same torque from the power source while absorbing the difference of the inner ring (difference in the speed of the inner and outer ring) which occurs when a vehicle is making a turn.

Features

(1) “NTN-One Motor Type EV Power Train”	This system is offered with the one motor EV drive system, by adding a constant-velocity joint, Multi Axis Load Sensor Integrated Hub Bearing and etc.
(2) Compact and lightweight drive system	By selecting the appropriate gear ratio according to the vehicle running conditions, this system provides smooth acceleration even with a compact and lightweight drive motor, and enables high speed running
(3) High efficiency by the unique two-speed automatic transmission	Allows for smooth shifting in a short time by the cooperative control between the vehicle drive motor and shift actuator Improves system efficiency and increases the cruising range per charge, by selecting the appropriate gear

Application

One motor type EV

Inquiries about this release

Photo of Product

Photo of Product: One Motor Type EV Drive System (Excluding Inverter)

One Motor Type EV Drive System (Excluding Inverter)

Photo of Product: Constructural Example of an NTN-One Motor Type EV Power Train

Constructural Example of an NTN-One Motor Type EV Power Train