Siemens SINAMICS G150 Operating Instructions Manual page 408

Setpoint channel and closed-loop control
7.4 Vector speed/torque control with/without encoder
A "real" closed-loop torque control (with a speed that automatically sets itself) is only
possible in the closed-loop control range but not in the open-loop control range of the
sensorless closed-loop vector control. In the open-loop controlled range, the torque setpoint
changes the setpoint speed via a ramp-up integrator (integrating time ~ p1499 x p0341 x
p0342). This is the reason that sensorless closed-loop torque control close to standstill is
only suitable for applications that require an accelerating torque there and no load torque
(e.g. traversing drives). Closed-loop torque control with encoder does not have this
restriction.
OFF responses
● OFF1 and p1300 = 22, 23
● OFF1, p1501 = "1" signal and p1300 ≠ 22, 23
● OFF2
● OFF3
Function diagram
FP 6060
406
– Response as for OFF2
– No separate braking response; the braking response is provided by a drive that
specifies the torque.
– The pulses are inhibited when the brake application time (p1217) expires. Standstill is
detected when the speed actual value of the speed threshold (p1226) is undershot or
when the monitoring time (p1227) started when speed setpoint ≤ speed threshold
(p1226) expires.
– Switching on inhibited is activated.
– Immediate pulse suppression, the drive coasts to standstill.
– The motor brake (if parameterized) is closed immediately.
– Switching on inhibited is activated.
– Switch to speed-controlled operation
– n_set = 0 is input immediately to brake the drive along the OFF3 deceleration ramp
(p1135).
– When standstill is detected, the motor brake (if parameterized) is closed.
– The pulses are inhibited when the motor brake closing time (p1217) has elapsed.
Standstill is detected when the speed actual value of the speed threshold (p1226) is
undershot or when the monitoring time (p1227) started when speed setpoint ≤ speed
threshold (p1226) expires.
– Switching on inhibited is activated.
Torque setpoint
Converter cabinet units
Operating Instructions, 03/2012, A5E03263466A