Direct drive: removing the gearbox
A direct-drive PMSM is coupled directly to the load, with no gearbox. For low-speed, high-torque machines (such as mixers, rollers, hoists, conveyors) this is ideal - no gearbox means less space, less maintenance, lower noise and higher efficiency.
Direct drive vs gearbox solution
| Item | Standard motor + gearbox | Direct-drive PMSM |
|---|---|---|
| Transmission | Needs gearbox | Direct |
| Efficiency | Gearbox losses | High |
| Noise | Higher | Low |
| Maintenance | Gearbox needs service | Low, near maintenance-free |
| Footprint | Coupling + gearbox | Compact |
Duties that suit direct drive
- Low speed, high torque: mixers, rollers, hoists, lifting.
- Precise positioning: no transmission backlash.
- Limited space: no gearbox, easy to fit.
- Noise-sensitive: no gear mesh, quieter.
Points to watch
Direct-drive motors need high torque and many poles, so they are often larger and heavier than an equivalent power standard motor; they also need a VFD (no direct mains start). Provide speed, torque and load inertia for proper selection.
Wangpai direct-drive range
Wangpai supplies TPTYC permanent-magnet direct drive (185~5000 kW), TYPKK HV PMSM and TYCP low-voltage PMSM, customised to load torque.
FAQs
Does a direct-drive motor need a VFD? Usually yes, since it is multi-pole and needs speed control.
Is direct drive more expensive than gearbox? The motor may cost more, but no gearbox plus less maintenance often makes it cheaper overall.
Can direct drive handle high speed? It suits low-speed high-torque; for high speed consider a VFD-optimised design.