Forward and reverse rotation control circuit and method for sensorless motor, and motor controller

A forward and reverse rotation control circuit for a sensorless motor, comprising:

• a logic controlling module configured to provide configuration parameters and control signals, wherein the configuration parameters comprise a forced-dragging angular increment and an initial value of a forced-dragging angle, and the control signals comprise a forward and reverse rotation control signal and a selection signal;
• a rotor angle calculating module configured to receive the forced-dragging angular increment and the initial value of the forced-dragging angle provided by the logic controlling module, and obtain a calculated rotor angle value through accumulation;
• a rotor angle estimating module configured to estimate an angular increment based on voltage signals and current signals of the motor, limit an estimated angular increment value based on the forward and reverse rotation control signal provided by the logic controlling module, and obtain an estimated rotor angle value through accumulation;
• and
• a selecting module configured to select to control the motor according to the calculated rotor angle value output by the rotor angle calculating module or the estimated rotor angle value output by the rotor angle estimating module based on the selection signal provided by the logic controlling module.