The present invention relates to a training apparatus comprising a training element for a user performing exercises an AC motor and a frequency converter being arranged to control AC motor. The frequency converter comprises measuring means being arranged to measure voltage and current of AC motor and calculation means being arranged to calculate magnetic state of the AC using the measured voltage the measured current a reference torque and a reference flux in order to generate torque of the AC motor. The training apparatus further comprises a control unit having a machine control module being arranged to calculate reference flux and reference torque using an intended overall torque wherein the machine control module is connected to the frequency converter and arranged to transmit reference flux and reference torque to the frequency converter. Further the present invention comprises training arrangement comprising training apparatus and method for operating the training arrangement.
