Planetary coupled diesel electric hybrid
Planetary coupled diesel electric hybrid
(OP)
I am tasked with desiging a test setup consisting of a 200 kw diesel engine, and a 90 kw (continuious) electric motor coupled through a planetary gear set.
The diesel will drive the ring, the motor will drive the sun, and the output will be taken off the carrier.
My concern is with the planet set:
1. Can it take speeds and torques?
2. How should it be lubricated?
3. How should it be supported?
4. How should it be sized?
One option is to use an existing planet set out of a large Allison automatic transmission and modify it to suit our needs, the other is to design and build one our selves.
Are there any resources available, specific to planet gear design?
The diesel will drive the ring, the motor will drive the sun, and the output will be taken off the carrier.
My concern is with the planet set:
1. Can it take speeds and torques?
2. How should it be lubricated?
3. How should it be supported?
4. How should it be sized?
One option is to use an existing planet set out of a large Allison automatic transmission and modify it to suit our needs, the other is to design and build one our selves.
Are there any resources available, specific to planet gear design?





RE: Planetary coupled diesel electric hybrid
How about the Epicyclic Gear Train page at Efunda.com(www.efunda.com): www.efunda.com/DesignStandards/gears/gears_epicyclic.cfm
Best regards,
Matthew Ian Loew
"Luck is the residue of design."
Branch Rickey
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Planetary coupled diesel electric hybrid
There is software to do gear design, but the learning curve and cost make in unattractive to all but gear manufactures.
If it is a test setup, and the reduction ratios are not too large, a belt drive would be less expensive to use. The disadvantages are belt tension side load, and shaft center distances.
RE: Planetary coupled diesel electric hybrid
Googling using "diesel electric hybrid bus" got lots of hits.
There are probably research papers on these test systems also (ASME ?).
RE: Planetary coupled diesel electric hybrid
We are not developing a test unit for a system, we are developing THE system, and then testing it.
I am looking for information specfic to either; 1. planetary gear design. or 2. a good source for off the shelf planetary gear sets.
I can't use belts or chains any more than I can PUSH a car up a hill with a rope.
RE: Planetary coupled diesel electric hybrid
RE: Planetary coupled diesel electric hybrid
RE: Planetary coupled diesel electric hybrid
You may look into using in-production automatic transmission carriers that can be purchased from any auto dealer. For prototyping I think this is the only cost effective way to prove out an idea.
Off the cuff I would say that any of the larger rear wheel drive carriers should easily handle your torque and splash feed ATF is sufficient (at low speeds).
RE: Planetary coupled diesel electric hybrid
You will get reduction between the three parts of a planetary drive. The Machinery’s Handbook has some information about ratios and direction of rotation. As to off shelf gearing, the best you can hope for is transmission or final drive parts from commercially built equipment. Back in the 1980’s we spent some time trying to build a steering differential for a tracked vehicle from these parts and found it not possible, wrong ratios, or incompatible gear teeth. In 2000 we spent some time looking at planetary drive again for a different application and found nothing different. If you contact people who make planetary final drives for construction equipment, they might be able to help you with design and manufacture.
If you are trying to have the armature concentric to the diesel motor shaft, the electrical components will have to be sealed from any oil in the gear train.
If you want to declutch the armature, this design will require even more work. You may be able to use clutch packs from power shift transmissions, but finding design information is difficult.
RE: Planetary coupled diesel electric hybrid
I assume you are replacing a conventional auto transmission with a hybrid system? What motor technology are you using out of interest? Must be pretty chunky, acting as generator and motor. Will torque equal engine torque or are you using a several epicyclic stages and auto box style brakes?
I have wondered for yonks about combining auto boxes and motors...
Mart