Latest electrification technologies：Bosch, Schaeffler, ZF, and Jatco
48V mild-hybrid system, motor-drive systems, hybrid modules
In this report we give an update on the latest electrification technologies either already developed or under development by major suppliers, which were exhibited at the Tokyo Motor Show 2015.
Robert Bosch GmbH exhibited its 48V mild-hybrid system that the company plans to launch around 2016. Schaeffler AG exhibited hybrid modules capable of being equipped on current models, 48V-compatible electric stabilizers, and other products. ZF Friedrichshafen AG exhibited an all-electric, automated-driving concept car that has front-axle steering angles of up to 75 degrees, promoting its autonomous-driving technology.
NSK Ltd. exhibited an EV drive system consisting with traction reducer that transmits power without using gears. NTN Corporation displayed a two-motor drive system that achieves torque vectoring based on the two, individual drives being housed on the left and right wheels, respectively. Jatco Ltd. is in the process of developing a CVT that achieves a 40% reduction in terms of three aspects: size, weight, and friction, which are going to be needed even more in the future for all types vehicles such as gasoline, all-electric, etc.
European OEMs and suppliers plan to launch 48V hybrid systems after 2016 (Feb. 2015)
Bosch: Plans to launch 48V hybrid system around 2016
Bosch calls its 48V hybrid system the "Boost Recuperation System" (BRS). Increasing the voltage from the standard12V to 48V will increase internal electric power consumption from 4kW to 15kW. If vehicles are equipped with motors and generators compatible with 48V hybrid systems, it will be possible to enhance driver-assist functions and power-regeneration capabilities. Electric power can be supplied to 12V electric devices by lowering the voltage with DC-DC converters.
Various components such as a 48V motor/regenerator, lithium-ion battery, and DC-DC converter are integrated into Bosch's BRS. The engine can provide a maximum of 10kW of power to assist various onboard systems. For example, this means that fuel consumption can be reduced by 15% in vehicles equipped with stop/start systems.
First generation: 48V motor/generator can be fitted where the existing alternator is installed.
The motor's power can assist the engine simply by connecting a belt to the crank shaft, achieving a significant advancement because extensive design changes are not needed. Bosch predicts that European OEMs will begin fitting their models with its BRS sometime in 2016, and by 2017, its BRS will be in general use among other OEMs.
Second generation: A system that can be powered by the motor alone.
The torque from the motor will be transmitted through the gears, so OEMs can choose to fit the motor either in front or behind the transmission, according to their individual requirements.
Schaeffler: rear-wheel drive system and hybrid module
Rear-wheel drive system
Schaeffler displayed its rear-wheel drive system, which is a drive system designed for use on rear wheels of electric cars. It is coupled to a two-speed transmission and has torque-vectoring capability. The company foresees commercial production in about two to three years down the road. It can be built into various types of modules with the addition of different parts such as only a motor, or a transmission, or only a reducer. When this system is equipped on front-wheel-drive vehicles with front-engine-mounted convertible-combustion engines, the vehicles can be turned into plug-in hybrid vehicles.
|The drive motor can be seen on the right of the photo. On its left is the transmission mounted to it. The motor seen in the upper right is a torque-vectoring motor, which is not used to for drive.|
This hybrid model, which can be installed between the engine and transmission, integrates the motor and the clutch that connects the engine with the transmission, enabling it to be coupled with all types of transmissions such as automatic, manual, continuously variable, and dual-clutch. This hybrid module's particular selling point is its ability to be supplied as a single unit that includes a motor, clutch, damper, and other components. Its torque capacity and motor power can be adjusted according to customer needs. The company has decided to mass-produce it from 2017.
Power stabilizer (roll stabilizer)
This latest power stabilizer (or roll stabilizer) is the result of Schaeffler's electrifying an adjustable stabilizer and enabling it to control vehicle roll when the vehicle is cornering. It provides superior performance in terms of efficiency and response compared to hydraulic adjustable stabilizers. It is being supplied to the new BMW 7 Series. Its rated torque is 1200Nm, tension angle is ±30 degrees, and weight is 12kg (including actuator and ECU).
It is being designed to be 48V compatible, which will even further boost its efficiency and response. The Company is planning to deliver it to German OEMs in 2016.
|Power stabilizer (48V type)||Torsion-control part: comprised of planetary reduction gear and brushless DC motor|
Vehicle height-control actuator
This actuator, which is still under development, is connected to the suspension. Its motor and ball-screw control vehicle height in order to improve the vehicle's aerodynamics such as by reducing drag while on highways. Its efficiency and response are far superior to air-suspension control. It can be used like a stabilizer also, as it is capable of changing the vehicle's height from side to side.
|Vehicle height-control actuator|
ZF: Advanced Urban Vehicle concept with 75-degree steering angle
This Advanced Urban Vehicle is ZF's proprietary concept car. It is equipped with a semi-independent rear suspension, called a rear-wheel electronic twist beam (eTB); and two 40kW motors fitted on the left and right wheels, respectively.
* Front-wheel steering angle is 75 degrees, rear wheels are each powered individually, and turning clearance is under 6.5m * Mounted with automated-parking system: Drivers are able to activate this parking system with mobile devices like smartphones, smartwatches, etc. while they are in the driver's seat or when they are outside the vehicle. The system automatically selects an appropriate space nearby and parks the vehicle. This concept car is equipped with 12 ultrasonic sensors and two infrared sensors. * PreVision Cloud Assist stores all sorts of information such as the vehicle's traveling speed, latitude/longitude, etc. If the vehicle travels over the same route again, the system selects the optimum driving pattern, such as speed, based on the data stored previously during the first time traveling over the road. For instance, the system will eliminate the need for the driver to step on the brake, by remembering the previous condition and automatically throttle back the torque accordingly. * Multifunction steering wheel rim is equipped with an organic electroluminescence display (OLED) that shows data from and state of the PreVision Cloud Assist. In addition, there are touch-sensors on the steering wheel capable of detecting whether the driver is gripping the wheel.
|Advanced Urban Vehicle||Electric twist beam|
|Front wheel with 75-degree steering angle||Multifunction steering wheel|
NSK: Debuted dual-motor drive system
New EV drive system combines high-speed motor and traction reducer
This new EV drive system, which is includes a compact, high-speed motor (30000rpm) and a traction reducer, is a drive mechanism capable of powering the vehicle. Even equipped with the high-speed motor and traction reducer, this system is still lighter than conventional electric motors mounted on electric cars. The traction reducer, which is gearless, transmits power via rollers (or through rolling) when a special oil, which instantly hardens only when compressed, passes between them. This drive provides excellent performance in terms of low friction, loss, and noise because the rollers never come into contact with each other.
|New EV drive system (from left to right: reduction drive, traction reducer, and motor)||Enlarged image of traction reducer|
Wheel-hub motor: with built-in transmission function
Housing two motors inside the wheel hub enables them to perform the function of the transmission. In other words, when the vehicle is running in high gear, the two in-wheel motors both rotate in the same direction. However, when the driver changes gears, whenever the two in-wheel motors change their direction of rotation, the one-way clutch that is sandwiched between the two motors controls the carrier, and the vehicle changes into low gear.
NTN: Two motor on-board drive system
NTN developed a drive system that separately powers individual motors fitted on both left and right wheels. This system consists of two motors and a reducer that achieve torque vectoring. As a result, this latest system enhances turning performance and running (run-through) performance on slippery roads. Modularizing the system by integrating the hub-bearing and drive shaft, the Company is making product presentations to OEMs, highlighting the system's major selling points, which are performance and lower cost. The company targets sales of JPY 1.5 billion in its FY2025.
|2-motor onboard drive system|
Jatco: Reduced size, weight, and friction each by 40% of CVT under development
Jatco displayed a mockup of its future CVT still under development. The company, which is aiming to launch this future CVT around 2020, is working to reduce its size, weight, and friction each by 40%. In addition, it is working to increase its transmission efficiency compared to the current level of existing products, which is somewhere in the range of 80%, to 93%. At the moment, Jatco is testing this future CVT on test vehicles, working on issues such as costs, quality, and delivery date.
Jatco is developing this one CVT with the idea of making it compatible with all types of powertrains such as those for all-electric vehicles, fuel-cell vehicles, and hybrid vehicles. Currently, only a few electric cars have transmissions. The company feels it would be more efficient to use a combination of downsized motors married to transmissions, by making optimum use of the highly efficient, inherent nature of motors, rather than make motors even larger to meet the need for larger-sized and faster running electric cars, for which there will be greater demand in the future. As a result, CVTs will have to be made more efficient while being made lighter and smaller at the same time.
|CVT Future Concept: Exhibit showing CVTs being used in gasoline, hybrid, and all-electric cars in the future|
<Automotive Industry Portal MarkLines>