A direct power control for three-phase rectifier based on positive sequence detection

In this paper a model-based controller is proposed for the direct control of the instantaneous active and reactive powers in a three-phase rectifier. As the unbalanced operation is considered, it is convenient to express the grid voltage in terms of both positive and negative sequences in order to obtain a more complete description of the system. In particular, the positive sequence of the grid voltage is used as the transformation basis to generate the instantaneous powers. The controller incorporates an adaptation mechanism to cope with the parameters uncertainties. It is observed that, by using the positive sequence of the voltage signal, the regulation of the instantaneous powers is possible without deformation of the line current. Numerical results are provided to illustrate the performance of the proposed solution.