Field-winding rotating electrical machine

A field-winding rotating electrical machine comprising:

• a motor generator having a field winding;
• a field current detecting section for detecting field current flowing in the field winding;
• a field current control section for controlling the field current;
• a field current limiting section including a field current limitation determining section for calculating a determination value based on the field current detected by the field current detecting section and determining whether or not the determination value has reached a predetermined determination threshold value, and a field current limitation instructing section for, in response to the field current limitation determining section determining that the determination value has reached the predetermined determination threshold value, generating a field current limiting instruction and transmitting the field current limiting instruction to the field current control section so as to limit the field current to be equal to or smaller than a predetermined permissible value during a predetermined field current limitation time;
• and
• a field current limitation releasing section for outputting a field current limitation releasing instruction to the field current limiting section, the field current limitation releasing instruction comprising an explicit instruction to release limitation of the field current during a predetermined field current limitation release time that is a time period falling within the predetermined field current limitation time, wherein
• the field current limiting section, in response to having received the field current limitation releasing instruction from the field current limitation releasing section, releases limitation of the field current during the predetermined field current limitation release time and resumes limiting of the field current in response to expiration of the predetermined field current limitation release time.