• No : 21483
  • Release Date : 2018/08/22 16:27
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Operation under torque limit in the speed control mode

I use the vector inverter FR-V220E-11K for a winding machine.
A single inverter is used to manually control the speed and limit (manually adjust) the torque.
The above operation is required.
For example, when operating at 50 Hz under a 50% torque limit and the torque is about to exceed 50%, the speed is automatically lowered to keep the torque at 50% and continue operation.
When the torque limit value is increased to 60% in this condition, does the inverter operate within the frequency range below 50 Hz so that the 60% torque limit is not exceeded?
Category : 

Answer

Under a 50% torque limit, if the commanded speed (50 Hz in your example) cannot be achieved without torque exceeding 50%, since the torque does not exceed the 50% limit, the inverter operates at the highest speed that does not exceed the 50% torque limit.

Since this inverter control targets the torque limit, it is not speed control but torque control.
If the torque limit value is increased to 60% in this condition, inverter control switches from torque control to speed control, and raise the speed toward the commanded speed. If the commanded speed (50 Hz) can be achieved under the 60% torque limit, the inverter accelerates to the commanded speed. If the torque reaches the limit value, the inverter operates at the highest speed that does not exceed the 60% torque limit.
Product Name
Inverter, magnet motor drive
Product Category
Inverter
Series
FR-V200