"Julian" wrote in message
...
"Doctor Drivel" wrote in message
reenews.net...
Me, I think hybrids are stupid for all kinds of engineering reasons. I
have
no intention of buying one.
You have no idea how the Prius works. It is "simpler" than a normal car.
Can you help me understand how it's "simpler" please?
I knew next to nothing about the P, so looked it up he
http://en.wikipedia.org/wiki/Toyota_Prius
It looks an effing complicated thing to me compared to
engine-clutch-gearbox of a normal car.
It is simple. An engine and motor in parrallel. A power splitter which
varies the ratio of power given by both motors - one could be giving 10% and
the other 90% or anything between or the reverse. This power splitter
presents the power of both motors directly to the wheels without an in-line
gearbox as does an electric motor in an EV car (they don't have gearboxes).
The power splitter effectively presents to the wheels the effect (in torque
and power) of one electric motor. There is NO in-line gearbox.
It has;
- an engine (as a normal car, although specially tuned for maximum )
- an electric motor (as a normal car - starter motor)
- a battery setup (as a normal car, but larger)
It does not have:
- an inline gearbox
It gives:
- superb economy in town driving
- ultra low pollutio levels, especially in town (the engine and motor are
off when the car is stopped)
- a superb ultra silent ride.
- seamless ride on no transmision steps (great for pasengers).
Also that Atkinson cycle engine needs replacing with a Diesel.
It doesn't at all. Noisy, smelly, vibrating diesels are good for tractors.
Split a powertrain into three modules:
1 petrol motor,
2 gearbox (CVT or otherwise),
3 diff/wheels It is in sequence,
1, 2, 3. Simple.
The petrol motor need module 2 because of its poor torque delivery
characteristics. An electric motor has modules 1 and 3, eliminating 2, as it
can deliver 100% torque to module 3 on start up. Super simple. The best.
A Prius has modules 1 and 3, like an electric motor. In module 1 it has an
electric and petrol motor. In module 1 it has a mechanism to automatically
combine the power/torque of an electric and petrol motor to give the torque
delivery characteristics of an electric motor.
Some experimental petrol engines can have modules 1 and 3 only, eliminating
2. This is by automatically varying the valve timing by using solenoid
controlled valves. This will deliver the torque to module 3 similar to an
electric motor. As with a Prius an auto mechanism is there to present to
module 3 torques characteristics like an electric motor.
So, no in-line gearbox, gear cogs, or CVT or otherwise in a Prius.
The point behind a Pirus is to:
- Have no to very low emissions in urban conditions
- reduce fuel consumption, and hence emissions
Ferdinand Porche raced (and won) a sort of hybrid in the early 1900s. They
were petrol motors - generators - electric motor - diff/wheels. In
effect an electric CVT "gearbox", all in-line, where the generator and
electric motor replaced a mechanical gearbox/CVT. The generator/electric
motor does the same job as a mechanical gearbox/CVT. A Prius does not use
this setup at all, it has the two motors in parrallel.
The Prius doesn't have an "in-line" transmission (gearbox/CVT). The "clever
part" is that is combines the outputs of the electric and petrol motors to
give the characteristics of one electric motor, presenting the
characteristics of an electric motor to the diff/wheels. Module 3 thinks
that its input is an electric motor.