A Novel Speed Measurement Method for a High-Speed BLDC Motor Based on the Signals From the Rotor Position Sensor

The paper presents a digital algorithm of a speed control block for a dc brushless motor and a method for measuring the motor's rotational speed based on the signals from the rotor's position sensor. The proposed method allows an increase in the measurement frequency (six measurements per rotation for a two-pole motor or 12 measurements for a four-pole motor) and the measurement results are not affected by the misalignment mounting of the sensor. The paper describes a conceptual structure of a series PI controller.