How they work together
The system uses three clutches as well as a planetary gear set that includes a centre “SUN” gear and a larger-diameter “RING” gear. The main electric motor is always connected to the sun gear, while two clutches can lock the ring gear or connect it to the smaller generator/motor. The third clutch connects the 1.4-litre gas engine to the generator/motor. There are four driving modes:
1. Low-speed electric driving: the main electric motor is the only one at work, while the ring gear is locked and the generator/motor is decoupled from it.
2. High-speed electric driving: as you speed up, the ring gear is unlocked and the generator/motor is connected to it for extra power and two extra miles of range.
3. Low-speed extended-range driving: when the battery pack is depleted, the gas engine is coupled to the generator/motor and provides energy to keep the batteries at their minimum state of charge while the main electric motor keeps the car rolling. You can’t fully replenish the battery pack with the gas engine.
4. High-speed extended range driving: both electric motors are active, while the generator/motor is also connected to the gas engine. However, in no case can the gas engine run the car without the main electric motor.
All this is pretty complex, but no need to worry; the transition between the four modes is seamless to the driver, apart from hearing the gas engine fire up.
The range
Fully charged, the Volt has an electric-only range of about 40 miles (64 km), but it can vary wildly. Drive the car like you stole it on a cold winter day, and your range will likely be as low as 25 miles or 40 km.
The system uses three clutches as well as a planetary gear set that includes a centre “SUN” gear and a larger-diameter “RING” gear. The main electric motor is always connected to the sun gear, while two clutches can lock the ring gear or connect it to the smaller generator/motor. The third clutch connects the 1.4-litre gas engine to the generator/motor. There are four driving modes:
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| Photo: Chevrolet |
1. Low-speed electric driving: the main electric motor is the only one at work, while the ring gear is locked and the generator/motor is decoupled from it.
2. High-speed electric driving: as you speed up, the ring gear is unlocked and the generator/motor is connected to it for extra power and two extra miles of range.
3. Low-speed extended-range driving: when the battery pack is depleted, the gas engine is coupled to the generator/motor and provides energy to keep the batteries at their minimum state of charge while the main electric motor keeps the car rolling. You can’t fully replenish the battery pack with the gas engine.
4. High-speed extended range driving: both electric motors are active, while the generator/motor is also connected to the gas engine. However, in no case can the gas engine run the car without the main electric motor.
 |
| Low-speed electric driving (Photo: Chevrolet) |
All this is pretty complex, but no need to worry; the transition between the four modes is seamless to the driver, apart from hearing the gas engine fire up.
The range
Fully charged, the Volt has an electric-only range of about 40 miles (64 km), but it can vary wildly. Drive the car like you stole it on a cold winter day, and your range will likely be as low as 25 miles or 40 km.