E-Drive system in a 644 X-Tier loader
E-Drive system components
What it Is
The Electric Drive system (E-Drive) is composed of a brushless electric generator and motor, power electronics (inverter), an electric brake resistor, and a simplified PowerShift™ transmission. This E-Drive system offers next level size class performance, ease of operation, and longevity to customers that invest in this innovative technology. The entire system works to dynamically adjust engine speed to meet tractive and hydraulic loads, ensuring 644 X-Tier loaders can maintain stockpiles, heap hoppers, and load trucks with the highest efficiency. All of John Deere’s E-Drive components are performance proven with over 2 million field hours accumulated and counting.
How It Works
- Brushless generator converts rotational energy from the engine into 3-phase alternating current (AC) electrical energy
- AC energy is supplied to the inverter, which delivers energy to the motor based on operator demand
- Single brushless electric motor converts AC energy back to rotational energy and torque, replacing the job of a torque converter
- Simplified PowerShift™ transmission maintains smooth shifting across four operating speed ranges
- When decelerating, the electric motor can also act as a generator to recapture energy from the loader’s inertia and recycle it back into the system
- Brake resistor passively consumes excess recycled energy whenever the inverter actively controls its circuit
Why it Matters
- Electric motor doubling as a generator when decelerating reduces engine load and fuel consumption
- Electric motor turns transmission bi-directionally to switch from forward to reverse, eliminating directional control clutch pack from transmission and reducing shifting
- Brake resistor dissipates excess recaptured energy, reducing brake wear and lowering maintenance costs
- Maintaining a constant engine speed of 1600 rpm reduces engine wear and increases fuel efficiency without sacrificing performance
- The inverter constantly monitors all energy in the system and determines the most efficient path
- Brushless motor and generator provide quieter operation ideal for commercial and residential areas