Efficient Networks S120 manual Series reactor, Commissioning/optimization

Servo control 3.11 Sensorless operation (without an encoder)

Series reactor

When high-speed special motors are used, or other low leakage induction motors, a series reactor may be required to ensure stable operation of the current controller.

The series reactor can be integrated via p0353.

Commissioning/optimization

1.Estimate the motor current p1612 on the basis of the mechanical conditions (I = M/kt).

2.Set Kn (p1470) and Tn (p1472) above I/f operation (> p1755). The load moment of inertia should be set to zero here (p1498 = 0), since this deactivates part of the torque pre- control.

3.Determine the load moment of inertia in the speed range above I/f operation (> p1755) by setting p1498 via a ramp response (e.g. ramp time 100 ms) and assessing the current (r0077) and model speed (r0063).

Function diagrams (see SINAMICS S List Manual)

●5050 Kp_n-/Tn_n adaptation

●5060 Torque setpoint, control type switchover

●5210 Speed controller

Overview of key parameters (see SINAMICS S List Manual)

●p0341 motor moment of inertia

●p0342 Ratio between the total moment of inertia and that of the motor

●p0353 Motor series inductance

●p0600 Motor temperature sensor for monitoring

●p0640 current limit

●p0642 Sensorless current reduction

●p1300 Open-loop/closed-loop control operating mode

●p1400.11 Speed control configuration; sensorless operation actual speed value start value

●p1404 Sensorless operation changeover speed

●r1407.1 CO/BO: Status word speed controller; sensorless operation active

●p1470 Speed controller sensorless operation P-gain

●p1472 Speed controller sensorless operation integral-action time

●p1498 Load moment of inertia

●p1517 Accelerating torque smoothing time constant

●p1612 Current setpoint, open-loop control, sensorless

●p1755 Motor model without encoder, changeover speed

●p1756 Motor model changeover speed hysteresis

Drive Functions	91
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4