Liebherr T 282B – Worlds Biggest Hybrid

This is the first in a series of articles that will take a look at the worlds biggest electric vehicles in an effort to dispel the myth that EVs have to be low powered vehicles. The Liebherr T 282B, for example, is a 3650 hp (2700 Kw) Mine truck with a maximum operating weight of almost 600 tonnes that is not only the worlds biggest Diesel electric truck but is also the biggest AC drive truck in the world.

Unlike other Mine trucks in the 400 t class such as the Caterpillar 797B which use a torque converter with a 7 speed automatic gearbox, the T 282B takes advantage of high efficiency and maintenance free diesel-electric locomotive technology. Siemens provide the two AC induction motors for the rear axle, engine mounted generator and the solid state computer controlled power inverters that are proven over millions of operating hours in trains. Not only is the AC drive system lighter than either mechanical or DC transmission systems, they provide faster acceleration and a higher top speed.

The T 282B has electric retarders that can slow the truck to a stand still which provides precise speed control on descent using built in cruise control which works in both drive and retard modes. The electric retarders can apply over 6,000 hp (4,489 Kw) worth of braking effort. Unfortunately this in not a battery hybrid so the regenerated energy is not stored for later use but is burnt off through a stainless steel resistor grid. The AC system also has a solid state electronic differential that provides wheel independent traction and yaw control in both forward and reverse.

The Diesel engine that generates the drive electricity is a monster 90 liter (5,490 cubic inch) V20 twin turbo built by MTU that is big enough to be used as an emergency power generator for international airports. When running at the red line of 1800 rpm the 10 tonne lump of steel produces 2.7 Megawatts (3,650 hp)

As an option for significant fuel savings the AC drive in the T 282 has been designed to operate with an overhead trolley pantograph system. These overhead lines can often be seen on steep grades leading out of deep open cut mines.