| 摘要 |
PURPOSE:To make it possible to detect deterioration of insulation resistance during operation of a rotary electric machine, by connecting a monitoring power source between a field circuit and the earth, and making operation of insulation resistance of field winding by leak current passing from the field winding to the earth. CONSTITUTION:When voltage is impressed onto a field winding 1 from a DC power source 6, which is built in a field ground relay 5, through a field circuit 4b, a current collector brush 3 and a current collector ring 2 on the negative side, leak current passes to the earth through a field winding insulation resistance 12, and this leak current returns to the DC power source 6 through a leak current detector 8. This is detected by the detector 8 and put into an operation process by a circuit 9 together with a voltage of the DC power source 6 detected by the detection-operation circuit 9, and thereby an insulation resistance 12 of the field winding 1 is sought. Thus obtained value is indicated by an indicating device 10 and compared with a normal alarm setting value by an alarm device 11, and when the value proved to be lower than the setting value, an alarm is issued. It is possible, by doing so, to monitor insulation resistance during operation of a rotary electric machine and prevent the machine from being operated abnormally. |
