Week 4- Hybrid powertrains Flashcards
What is a hybrid vehicle?
A vehicle that has two or more powertrains.
What is a HEV?
A hybrid electric vehicle, one with an electric powertrain
What is a series hybrid (definition)?
It is a hybrid where only one energy converter can provide propulsion power. The IC engine drives the generator, and the generator either drives charges the batteries, or powers an electric motor that drives the wheels.
Draw the diagram for a series hybrid.
On canvas
What are the advantages of a series hybrid?
Advantages:
-Flexibility of location of engine generator
- Simplicity
-Suitable for short trips with stop and go traffic.
What are the disadvantages of a series hybrid?
Disadvantages:
-It needs 3 propulsion systems: engine, generator and motor
-Must be designed for maximum power, the vehicle rarely uses this
-All drivetrain components must be sized for long distance, high speed driving, this leaves the battery depleted meaning that the engine has to provide all the power.
What is a parallel hybrid vehicle? (definition)
It is a hybrid in which more than one energy conversion device can deliver propulsion power to the wheels.
What are the four types of parallel hybrid vehicle. Draw them.
Shown on canvas. One with one clutch, one with two clutches to allow for engine disconnection. Direct shift gearbox, where motor is a subject of the transmission. Through the road parallel, where the engine powers the front wheel and the motor powers the rear wheels.
What are the disadvantages of the parallel series?
The complexity of blending torque from the motor and engine
together requires complex mechanical parts, this is expensive.
What are the advantages of parallel series?
-Only needs two propulsion components, the IC engine and the motor.
-You can vary the power output between the motor and engine for better performance and less emissions.
What is a series-parallel hybrid (definition)?
An extension of the series hybrid but with an additional clutch that can mechanically connect the gearbox and motor
Draw the 3 series-parallel hybrids?
On canvas
