Abstract: In order to improve the measurement accuracy of the position and speed closed-loop of the brushless

DC motor，which is currently used in the attitude control actuator，a new cumulative pulse M/T method was

proposed，based on incremental off-axis magnetic encoder（AS5304A）and TMS570 chip internal integrated

enhanced quadrature encoder pulse（eQEP）module. By deep dive researching and experimental analysis，the

measurement accuracy of the entire operating speed measurable range can be maintained around 1%，and the highprecision speed measurement can be achieved as well. Compared with the traditional speed measurement scheme，the accuracy is significantly improved.

    Key words: brushless DC motor；enhanced quadrature encoder pulse（eQEP）module；incremental off-axis

magnetic encoder；M/T method