A Simple Multi-Vector Predictive Direct Power Control Using Geometric Modulation

This article proposes a simple multivector predictive direct power control (P-DPC) using geometric modulation. Different from the conventional counterpart using two active and one zero vector, the proposed multivector P-DPC uses a primary and a secondary equivalent vector having the opposite angular position to synthesise the voltage reference acquired from the deadbeat calculation. The generic equation of the rectifier voltage is established to calculate the primary and the secondary equivalent vectors as the weighted sum of two active vectors. The duty cycle optimization is achieved by combining the coefficients of the two equivalent vectors and the length ratio of the reference amplitude compared with the maximum rectifier voltage. The proposed multivector P-DPC offers a simple solution of duty cycle optimization that circumvents the calculation of instantaneous power rates and complex differential equations prevalent in conventional multivector approaches. This significant reduction of control complexity makes the proposed approach suitable to be implemented in low-cost microcontroller units. Experimental and simulation results have demonstrated the effectiveness of the new method.