Advanced Power Electronic Conversion and Control System for Universal and Flexible Power Management

Abstract

The future electricity network has to be able to manage energy coming from different grids as well as from Renewable Energy Sources (RES) and other Distributed Generation (DG) systems. Advanced power electronic converters can provide the means to control power flow and ensure proper and secure operation of future networks. This paper presents analysis, design and experimental validation of a back-to-back three-phase AC-DC-AC multi-level converter employed for Universal and Flexible Power Management (UNIFLEX-PM) of future electrical grids and its advanced control technique. The proposed system has been successfully tested for bidirectional power flow operation with different grid operating conditions such as voltage unbalance, frequency variation, harmonic distortion and faults due to short circuits

A Distributed Model Predictive Control Strategy for Back-to-Back Converters

“…With this aim, the switching states S1abc(t) and S2abc(t) are computed within each sampling interval, usually in the order of tens of microseconds [9], [18], [49], [50]. The two power converters considered here are traditional three-phase two level structures in order to simplify the system configuration and demonstrate the feasibility of the proposed control approach.…”

New configurations of power converters for grid interconnection systems

“…Recent initiatives of the Chilean government and recent research have focussed on "providing a more flexible and modular power electronics interface able to connect different kind of sources and loads including medium voltage electrical networks, renewable energy sources, and energy storage systems", such as the one illustrated in Fig. 2 which requires a flexible power management control in order "to ensure proper and secure operation of the networks" and bidirectional power flow [54].…”

Impact of the modularity on the efficiency of Smart Transformer solutions

“…In the distribution system, where the penetration of renewable energy power plants and high power domestic loads (both in AC and in DC) is increasing, the use of a three-stage architecture is preferred. According to that, it was adopted by the main research groups and companies developing SSTs for distribution like FREEDM [6], UNIFLEX-PM [7], EPRI [8] and GE [9].…”