Firmware
≤
11.00 - DMS 8.0 EN - 10/2011
L
175
8400 StateLine C | Reference manual
Motor control (MCTRL)
Sensorless control for synchronous motors (SLPSM)
The motor model-based speed monitoring requires a rotating machine. Thus, the
operational performance of the sensorless control for synchronous motors is divided into
two categories:
1. Open-loop controlled operation (|n
setpoint
| < n
C00996
)
– In the range of low speeds, the speed of a synchronous motor is not possible. Thus,
only an adjustable and constant current is injected that enables an acceleration.
2. Closed-loop controlled operation (|n
setpoint
| > n
C00996
)
– In this range, the rotor flux position and the speed are reconstructed via an observer.
The control is carried out field-oriented. Only the current is injected that is needed for
the required torque.
[5-13] Operating ranges of the sensorless control for synchronous motors
Stop!
• The injection of a constant current may cause an unwanted heating of the
motor at controlled operation.
– We recommend using a temperature feedback via PTC or thermal contact.
Motor temperature monitoring (PTC)
(
236)
Note!
Currently, the sensorless control does not contain a flying restart function that
enables a synchronisation of the controller to a rotating machine.
• Thus, we recommend taking measures for preventing overvoltages at
operation in generator mode (e.g. brake resistor).
• By any means, the delay time for the "DC-bus overvoltage" error trigger in
C00601/1
must be set to 0 s.
Operation in motor mode (CW rotation)
Operation in generator mode (CCW rotation)
Operation in motor mode (CCW rotation)
Operation in generator mode (CW rotation)
n
Field weakening (in preparation)
o
Closed-loop controlled operation
p
Open-loop controlled operation
0
1
2
3
M
n
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
