Low-voltage power supply filter circuit and motor controller

The invention discloses a low-voltage power supply filter circuit and a motor controller. The power supply filter circuit comprises multiple stages of differential mode filter units which are sequentially connected in series. The adjacent differential mode filtering units are connected through common mode inductors, and the common mode inductors are the first-stage common mode inductor to the (N-1) th-stage common mode inductor in sequence from the output end of the low-voltage power supply to the input end of the low-voltage power supply. One side winding of each common-mode inductor is connected in series with a low-voltage power supply positive line, and the other side winding is connected in series with a negative line; a common-mode Y capacitor is connected in series between the low-voltage power supply output end and the common ground on each side winding of each common-mode inductor, and a common-mode Y capacitor is connected in series between the low-voltage power supply input end and the common groun