Synchronous Motors: Overview
| Power supply | AC | |
|---|---|---|
| Driver electronics need | No | |
| Speed accuracy | High | Not effected by load torque No closed loop speed control need |
| Speed control | No | Not possible Speed fixed by mains supply frequency |
| Position control | No | Not possible Only by limit switches |
| Overloadablity / load inertia | Low | Only little reserve for peak load torque Can’t accelerate high inertia |
| Lifetime | High | Limited by bearings Depends on lateral force |
| Speed range [rpm] | 250…3600 | Depend on pole number and mains frequency |
| Efficiency | 15…45% | |
| Power vs. size | Low | |
| Winding thermal protection | No need | Inductance protected (if winding designed for 100% duty cycle) |
| Load sensing | Difficult | Load has little impact on current |
| Stalling permissible | Yes | If winding designed for continuous duty cycle |
| Electromag.interference EMI | Not Critical | No brushes |
| Braking/Holding torque | Low | Detent torque (when power switched off) |
| Linear motors from JE | Yes | |
| JE brand |   |
