Vector control
5.2 Vector control without encoder (SLVC)
Drive functions
214 Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Permanent-magnet synchronous motors
Permanent-magnet synchronous motors (PMSM) are always started and reversed in the
open-loop controlled mode. The changeover speeds are set to 10% as well as 5% of the
rated motor speed. Changeover is not subject to any time condition (p1758 is not evaluated).
Prevailing load torques (motor or regenerative) are adapted in open-loop operation,
facilitating constant-torque crossover to closed-loop operation even under high static loads.
Whenever the pulses are enabled, the rotor position is identified.
Figure 5-4 Zero point and starting in the open-loop controlled mode at low speeds
Synchronous reluctance motors
5.2.7.1
Synchronous reluctance motors (RESM) are operated with vector control (with/without
encoder). Synchronous reluctance motors are motors that do not have a damping cage. The
advantages of this motor type include:
● No rotor losses
● Energy efficient operation in the partial load range with reduced flux
● Fast magnetization at high load torques
Note
No V/f control
It is not permissible that synchronous reluctance motors are operated with V/f control, as this
is only intended for diagnostic purposes.