Aviation power supply converter AC voltage sampling circuit

The utility model discloses an AC voltage sampling circuit of an aviation power supply converter. The AC voltage sampling circuit comprises an autotransformer used for connecting a, b and c three-phase AC power grids; the output end of the autotransformer is connected with a main rectifier bridge, a first auxiliary rectifier bridge and a second auxiliary rectifier bridge, and the common positive polarity output end of the main rectifier bridge, the first auxiliary rectifier bridge and the second auxiliary rectifier bridge is connected with a filter inductor. A load resistor is connected to a common negative polarity output end of the main rectifier bridge, the first auxiliary rectifier bridge and the second auxiliary rectifier bridge, and a common output end of the filter inductor and the load resistor is connected with a DSP controller; according to the utility model, the input voltage of a three-phase alternating current power grid is rectified and then subjected to differential sampling, the waveform is sh