Performance Improvement of Permanent-Magnet Synchronous Motor Using a New Deadbeat-Direct Current Controller

In this paper, a new deadbeat-direct current control (DB-DCC) method is proposed in which two adjacent active-voltage-vectors (AVVs) with one zero-voltage-vector (ZVV) are applied to an interior permanent-magnet synchronous motor in each control cycle. In this method, by considering the sign of the error between stator-current components and their corresponding reference values, two AVVs are selected. Then, the changes of stator-current components due to applying these AVVs are formulated. At the next step, duty-cycles of these AVVs are calculated such that deadbeat control of the stator-current components is achieved. To improve the efficiency of the proposed DB-DCC method, reference stator-current components are adjusted based on the principle of maximum-torque-per-ampere, while the ZVV is selected such that the minimum switching transition occurs in each control cycle. Performance of the proposed method is assessed in MATLAB software and in practice where the results indicate that the proposed method reduces the stator-current total harmonic distortion in the steady-state and improves the dynamic response of the motor in the transient-state. The performance of the proposed DB-DCC method is compared with recent model predictive-current controllers and deadbeat controllers where it is observed that by adopting the proposed method superior performance is achieved.