Predictive Torque Control of Permanent Magnet Synchronous Motors Using Flux Vector

In this paper, an improved predictive torque control without weighting factor is proposed for a voltage source inverter-permanent magnet synchronous motor drive system, which possesses good control performance of torque and stator flux. By investigating the relationship among torque, the reference stator flux amplitude, and the phase angle of the stator flux, the reference stator flux vector is constructed. Then, the reference voltage vector is calculated by the reference stator flux vector based on the delay compensation and the deadbeat control. The extended control set is designed and two generalized base vectors that require further screening are determined based on the position of the reference voltage vector to improve the calculation efficiency. And the duty ratios used for the generalized base vectors are calculated, according to the geometric relations between the generalized base vectors and the reference voltage vector. Finally, by the duty cycle control between two generalized base vectors and between each generalized base vector and zero vector, the candidate vectors are gained and substituted into the cost function only with the flux vector error term. Experiment tests were carried out and the results validated the effectiveness of the proposed method.