Field winding rotating electrical machine and method for controlling field current of a field winding rotating electrical machine

A method of controlling a field current of a field winding rotating electrical machine,

• the field winding rotating electrical machine comprising:
• an armature winding;
• and
• a field winding,
• the method comprising:
• a field current detection step of detecting, by a field current detector, a field current flowing in the field winding;
• a field current control step of calculating a duty ratio of a current supplied to the field winding based on a field current detection value detected in the field current detection step, to thereby control current supply to the field winding by using a switching element;
• and
• a field current correction step of estimating a time point when the field current becomes 0 A based on a control state of the field current, specifying the field current detection value detected in the field current detection step at the estimated time point to be a field current correction value, and subtracting the specified field current correction value from the field current detection value detected in the field current detection step, to thereby calculate the corrected field current value,
• wherein the field current control step comprises controlling the current supply based on the corrected field current value calculated in the field current correction step.