Hybrid Electric Vehicle working | Hybrid Electric Vehicle Types
This page describes working of different types of Hybrid Electric Vehicles. The common Hybrid Electric Vehicle types are Mild Hybrid Electric Vehicle, Series Hybrid Electric Vehicle, Parallel Hybrid Electric Vehicle, Series Parallel Hybrid Electric Vehicle and Plug-in Hybrid Electric Vehicle. The difference between Hybrid Electric Vehicle types are also mentioned.
As we know Battery Electric Vehicle (BEV) consists of large electric motor and large battery pack. Moreover vehicle in BEV is powered entirely on electric energy. There are variations to BEV design based on number of battery packs, motors, use of clutch, gearbox, differential and fixed gearing etc. Hybrid Electric Vehicle (HEV) relies on two energy sources unlike BEV. They are internal combustion engine and electric battery and motor/generator. Let us understand Hybrid Electric Vehicle working with respect to different Hybrid Electric Vehicle Types.
Mild Hybrid Electric Vehicle
It is the least electrified type of HEV. It is conventional internal combustion engine vehicle with oversized starter motor which can also be used as generator. In this type of hybrid electric vehicle engine must always be ON while the vehicle is moving. When vehicle is in IDLE condition, motor/generator can be used to enable IDLE stop in which engine remains in OFF condition. At high loads, motor/generator can be used to assist engine to increase performance of the vehicle. At low loads, motor/generator increases load on the engine and recharges electric battery.
Series Hybrid Electric Vehicle
This HEV type uses single path to power the vehicle but uses two energy sources. As shown in the figure, fuel tank feeds engine which is coupled to generator to charge the battery. The battery provides electrical energy to a motor/generator pair used to power the wheels of vehicle. Motor/generator can be used to recharge battery during deceleration and braking. This series hybrid can also be designed using fuel cell powered by hydrogen. The series hybrid can operate in 7 modes viz. engine only traction, electric only traction, hybrid traction, engine traction and battery charging, battery charging and no traction, regenerative braking and hybrid battery changing.
Parallel Hybrid Electric Vehicle
This HEV type uses two parallel paths to power the vehicle hence the name. Transmission module couples both motor/generator and engine. The parallel hybrid can operate in five different modes viz. engine only traction, electric only traction, hybrid traction, regenerative braking, battery charging from engine.
Series Parallel Hybrid Electric Vehicle
This type of HEV uses both series as well as parallel power paths. The modules used in this hybrid electric vehicle type are shown in the figure.
Another type of HEV is plug-in hybrid electric vehicle which can be plugged in or recharged from wall electricity.