Three-phase motor forward and reverse rotation controller with braking function and braking method

The invention relates to the field of motor braking and discloses a three-phase motor forward and reverse rotation controller with a braking function. The controller comprises a logic control circuit, an input voltage detection circuit, a switch control circuit and an induced voltage detection circuit. When a motor is powered off and needs to be braked and the logic control circuit detects that the direction of phase line voltage and the direction of induced voltage are opposite through the input voltage detection circuit and the induced voltage detection circuit, a braking pulse signal is output, a corresponding switch of the switch control circuit is switched off or on, brake pulse voltage in the direction opposite to the induced voltage is input to a motor winding, a static magnetic field is generated through winding current, and a motor rotor quickly stops rotating due to braking torque. Capacitive energy storage needed by direct-current braking is not needed, size and cost are reduced, the brake pulse voltage can be accurately exerted at the moment that power grid voltage is opposite to the induced voltage by detecting the direction of the induced voltage, braking consistency and precision are high, service life is long, and electromagnetic interference is low.