Power supply method for motor generator set of AP1000 nuclear power unit reactor coolant pump

The invention discloses a power supply method for a motor generator set of an AP1000 nuclear power unit reactor coolant pump, which is characterized in that two sets of power supply systems are arranged from an upstream bus to a main pump and comprise a frequency converter power supply system and a motor generator set power supply system; and the frequency converter power supply system sequentially comprises a main pump loop switch, a main pump frequency converter, an electric reactor and a frequency converter outgoing line switch from an upstream bus to a main pump. The motor generator set power supply system sequentially comprises a set wire inlet switch, a motor generator set and a set wire outlet switch from an upstream bus to a main pump. The motor generator set comprises a synchronous motor with five pairs of poles, a synchronous generator with six pairs of poles, a matched motor excitation cabinet, a generator excitation cabinet, a set control cabinet and a set protection cabinet. The frequency convert