Modeling and Performance Assessment of the Split-Pi Used as a Storage Converter in All the Possible DC Microgrid Scenarios. Part II: Simulation and Experimental Results

Abstract

Bidirectional DC/DC converters such as the Split-pi can be used to integrate an energy storage system (ESS) into a DC microgrid providing manifold benefits. However, this integration deserves careful design because the ESS converter must behave like a stiff voltage generator, a non-stiff voltage generator, or a current generator depending on the microgrid configuration. Part I of this work presented a comprehensive theoretical analysis of the Split-pi used as an ESS converter in all the possible DC microgrid scenarios. Five typical microgrid scenarios were identified. Each of them required a specific state-space model of the Split-pi and a suitable control scheme. The present paper completes the study validating the theoretical analysis based on simulations and experimental tests. The chosen case study encompassed a 48 V, 750 W storage system interfaced with a 180 V DC microgrid using a Split-pi converter. It can represent a reduced-power prototype of terrestrial and marine microgrids. A prototypal Split-pi converter was realized in the lab, and several experimental tests were performed to assess the performance in each scenario. The results obtained from the experimental tests were coherent with the simulations and validated the study.

High-Efficiency and High-Performance Power Electronics for Power Grids and Electrical Drives

“…Proportional-integral-derivative (PID) controllers were employed, and the related design criteria were given. Then, in [8], the authors validated the theoretical analysis presented in [7] by performing several simulations and experimental tests. Future development of this work could be devoted to designing unconventional control systems for ESS converters suitable for operating in more than one microgrid scenario or, possibly, in all the scenarios.…”

“…This Special Issue includes ten contributions on various techniques aimed at improving the efficiency and performance in power electronics applications for power grids and electrical drives [1][2][3][4][5][6][7][8][9][10]. Such articles were authored by international research teams from several countries and covered different topics.…”

“…(a) Power converters used to interface RESs and ESSs with microgrids [1,3,5,7,8,10] or to recharge ESSs in electric vehicles [9]; (b) Performance increase in VSDs and direct online induction motors [4,6]; (c) Application of electrical loss minimization techniques to microgrids based on RESs [2].…”

“…Other contributions that fall into category (a) are [7,8] by Luna et al These papers were focused on the use of bidirectional DC-DC converters to integrate an ESS into a DC microgrid, ensuring stable operation and good dynamic performance. The authors showed that this integration deserves careful design because the ESS converter is required to work in different scenarios depending on the microgrid configuration.…”

Equivalent Modeling of Microgrids Based on Optimized Broad Learning System

“…Due to the complex internal structure of the microgrid and the difficult selection of component parameters, this method has a large workload and low fault tolerance [3,4]. The equivalent circuit method transforms the parts of microgrids into an equivalent circuit, and replaces the complex internal system of microgrids with an equivalent circuit, so as to reduce the difficulty of modeling [5][6][7]. The microgrids equivalent circuit modeling method is widely used in stability analysis and power flow calculation of large-scale power grid systems.…”