User Manual of EM760 High-Performance Inverter The rise time of VF separation voltage refers to the time for the output voltage to increase from 0 to the rated voltage of the motor. Fig. 7-2 Rise Time Description of VF Separation Voltage It is used to compensate for the voltage drop caused by the stator resistor and wire, and improve the low-frequency load capacity. As the load increases,the rotor speed of the motor will decrease. To make the rotor speed ofthe motor close to the synchronous speed underrated load, slip compensation can be enabled. When the motor speed is less than the target value, the set value ofF05.11 can be increased. * :
In the case of F05.11=0, slip compensation is invalid. This parameter is valid only for the asynchronous motor. The slip is 100% during the quick start with large inertia and 0 when the frequency reaches the set value. Quick increase or decrease of the output frequency will cause overvoltage or overcurrent. F05.12 filtering can slow down the rise ofvoltage and current. This parameter can be adjusted to suppress motor oscillations during the open loop control (VF). When the motor does not oscillate, this parameter should not be adjusted as little as possible or properly reduced. If the motor oscillates obviously, this parameter can be increased properly.
This function is usually applied for load distribution when one load is driven by multiple motors. Droop control is to reduce the output frequency of the inverter with the load increasing, so that the output frequency of the motor drops more ifit carries greater portion ofthe load driven by multiple motors, thus reducing the load on this motor and leading to evener distribution ofthe load on multiple motors.
204 Function code Function codename Parameter description Unit Default setting Attribute F05.09 Rise time ofVF separation voltage 0.00~60.00 s 2.00 ● Function code Function codename Parameter description Unit Default setting Attribute F05.11 V/F slip compensation gain 0.00~200.00 % 100.00 ● F05.12 V/F slip filtering time 0.00~10.00 s 1.00 ● Function code Function codename Parameter description Unit Default setting Attribute F05.13 Oscillation suppression gain 0~20000 300 ● F05.14 Oscillation suppression cutoff frequency 0.00~600.00 Hz 55.00 ● Function code Function codename Parameter description Unit Default setting Attribute F05.15 Droop control frequency 0.00~10.00 Hz 0.00 ●