Complete regenerative distributed drive system

Abstract

The paper is a result of the authors' researches in the field of energy area. The objective is to develop a power grid converter which includes all fundamental drive systems being capable to regenerate the energy into the grid. The topology fits very well to the hybrid renewable power systems, in order to control the green energy. Three-types of the electrical drives were included: the dc drive, the Induction Machine (IM)-based drive and the Permanent Magnet Synchronous Machine (PMSM) one. These drives are connected to the active loads, i.e. the load becomes under certain conditions as source. In order to deliver the energy from the active loads into the grid, the voltage source power converter (VSC) is used. By using the vector control the quasi unity power factor can be obtained. The cascaded control of the VSC assures the independent loop control of the active and reactive power. Additionally, the dc link voltage is maintained to the rated value through the outer loop control. Taking into consideration the different time constants between the cascaded control loops, the speed response of the outer loop should be increased when the perturbations of the system appears. The feedforward power control is one of the solution used in this paper. The cascaded loop control is also used for the load side. The vector control of both the induction machine and permanent synchronous magnet machine conducts to the increased performances of the overall system. For the dc drive, the full bridge dc-dc power converter ensures the bidirectional path for the circulated energy. The control parameters of the overall system are designed. The provided numerical simulation results underline the correctness of the proposed solution.