The ABB ACS880 Variable frequency drive has many auto-tune function to tune itself so that the drive can suit itself or make itself for the motor that is connected to it. This auto-tuning function in the ABB drive provides a good specification for its current motor application.
The auto-tune function helps to automatically do the drive speed control and this autotune is based on the mechanical time and constant inertia of the motor and machine. We can do the automatic speed control of this device in three different ways, for this first select the parameter section in the VFD and then select the complete list in the parameter section and in the complete list we can see the speed control which is the 25th select this parameter. We can see the 25th parameter is again divided into several sections. Select the parameter 25.34 which is to do the speed control in auto-tune mode. If we select the 25.34th parameter, we can see three different modes and they are smooth, normal, and tight. These modes show how the drive torque reference would react to the speed reference step after tuning.
The smooth mode will provide a slow and robust response, while the normal is a medium mode and tight will provide a fast response and they also provide high gain values for some applications. So the speed controlled is auto-tuned and the motor identification run is done, speed and torque limit is set. The speed feedback, speed error, and zero speed are also set and now the drive would run in a speed control mode. So the autotune is successfully done and its results will be transferred to the parameters 25.02 is the speed proportional gain, 25.03 is the speed integration time then the parameter 25.37 is the mechanical time constant. All these parameters can also be manually adjusted if we need.