Generator rotor alternating current impedance measuring device and one-point grounding measuring method

The invention provides a generator rotor AC impedance measuring device and a one-point grounding measuring method, and the device comprises a power operation box, an isolation transformer, a rotor winding, a first voltammeter, and a second voltammeter. Power output is controlled through a power operation box, and rotor alternating-current impedance and power loss measurement is completed according to measurement data transmitted by the first voltammeter and the second voltammeter; when one-point grounding measurement is carried out, according to one-point grounding resistance of a to-be-measured rotor between rotor windings, stray capacitance to ground of the rotor windings is summarized as stray capacitance to ground of a rotor positive electrode side and stray capacitance to ground of a rotor negative electrode side; a power supply is output through the power supply operation box, and rotor one-point grounding fault positioning and grounding resistance calculation are completed according to measurement data