Beihang University

Shiqiang Zheng

Tong Wen

Kun Wang

Haitao Li

Di Wang

Gang Liu

Kun Mao

Yun Le

Shitong Wei

Hao Jin

Sha He

A sensorless commutation error compensation system for a brushless motor, comprises: a brushless motor () and a commutation logic module circuit (). The commutation logic module circuit () is connected to three virtual Hall signal output ends of the brushless motor (), and used for receiving three virtual Hall signals output by the brushless motor (), obtaining three error compensation angle signals on the basis of the three virtual Hall signals, respectively superimposing the three error compensation angle signals and the three virtual Hall signals to form superposition results, and controlling the brushless motor () to adjust commutation timing on the basis of the superposition results, so as to achieve commutation error compensation. The system controls commutation errors on the basis of currents and counter-electromotive forces of three phases, instead of controlling the commutation errors on the basis of the current and the counter-electromotive force of one of the three phases, so that a torque ripple of a brushless direct-current motor can be reduced and a working efficiency of the motor can be improved.

Sensorless commutation error compensation system and method for brushless motor

The present disclosure provides a displacement detection circuit of a maglev rotor system and a displacement self-sensing system thereof. The displacement detection circuit comprises a current sampling circuit () configured to collect a current flowing through a corresponding coil (); coils (), which are coils () distributed in series in the maglev rotor system; Hall sensors (), the Hall sensors () being arranged in an upper auxiliary air gap () and a lower auxiliary air gap () of the maglev rotor system, and sensing surfaces of the Hall sensors () being perpendicular to magnetic field directions in the corresponding auxiliary air gaps (); a Hall signal processing circuit () connected to the Hall sensors () and configured to differentiate a Hall sensing signal corresponding to the upper auxiliary air gap () and a Hall sensing signal corresponding to the lower auxiliary air gap (); and a displacement signal resolving circuit () connected to the current sampling circuit () and the Hall signal processing circuit () respectively and configured to acquire a displacement of a rotor in the maglev rotor system according to the current and a differentiation result. By using the detection circuit and the displacement self-sensing system thereof, the axial size of the rotor is reduced, such that detection and control are coplanar, and high precision and simple design are realized.

Displacement detection circuit of maglev rotor system and displacement self-sensing system thereof

Growing community of inventors

Beijing, China

Shiqiang Zheng