Proton has confirmed i-HEV as the official name of its new hybrid powertrain. The system will debut in the upcoming model codenamed AMA 02.
The i-HEV combines a 1.5-litre petrol engine, two electric motors and an intelligent energy management system. It does not require external charging, allowing owners to refuel at conventional petrol stations.
1.5-Litre Dedicated Hybrid Engine
At the centre of the system is a naturally aspirated 1.5-litre Dedicated Hybrid Engine (DHE). It produces 111PS and 136Nm of torque, with a peak thermal efficiency of 46.5%.
The engine uses Atkinson cycle combustion to improve fuel efficiency. Its intake valve timing allows the expansion ratio to exceed the effective compression ratio, extracting more energy from combustion.
A 14:1 geometric compression ratio and water-cooled exhaust gas recirculation (EGR) further support combustion efficiency. The engine also uses a variable displacement oil pump and electric water pump to reduce energy consumption from auxiliary systems.
Two Electric Motors And Four Driving Modes
The engine works with a Dedicated Hybrid Transmission (DHT) containing two electric motors.
The P1 motor starts the engine and generates electricity. Meanwhile, the P3 motor drives the wheels and recovers energy during deceleration.
The main driving motor produces up to 163PS and 220Nm. A Power Control Module (PCM) coordinates the engine, motors and battery across four operating modes.
- EV Mode: The battery powers the driving motor, allowing electric-only operation when conditions permit.
- Series Mode: The petrol engine generates electricity while the electric motor drives the wheels.
- Parallel Mode: The engine and electric motor work together to drive the vehicle.
- Direct Drive Mode: The engine mechanically drives the wheels when this is more efficient, such as during steady-speed cruising.
The system automatically switches between these modes according to vehicle speed, power demand and battery condition. Drivers do not need to select them manually.
No External Charging Required
The i-HEV uses a 1.38kWh battery to store energy for electric driving and motor assistance.
Regenerative braking recovers energy during deceleration and stores it for later use. The petrol engine can also generate electricity through the P1 motor when required.
This allows the system to provide electric driving assistance without requiring owners to plug in the vehicle. It can also reduce engine operation during stop-and-go traffic.
Hybrid Powertrain Production In Malaysia
Proton is also developing local manufacturing capabilities for its electrified powertrains.
Its Tanjong Malim operations will locally assemble the Dedicated Hybrid Engine, Dedicated Hybrid Transmission and Electric Drive Units (EDU).
These activities are intended to develop local expertise in assembly, testing and quality control. They also support the development of Malaysia’s automotive supplier ecosystem.
The i-HEV system will make its first appearance in the upcoming AMA 02. Proton has yet to announce the model’s official name, launch date or pricing.
