System Level Simulation of Microgrid Power Electronic Systems

Kristian Takacs,Michal Frivaldsky,Jan Morgos,Michal Prazenica

doi:10.3390/electronics10060644

Abstract

In this paper, we describe a procedure for designing an accurate simulation model using a price-wised linear approach referred to as the power semiconductor converters of a DC microgrid concept. Initially, the selection of topologies of individual power stage blocs are identified. Due to the requirements for verifying the accuracy of the simulation model, physical samples of power converters are realized with a power ratio of 1:10. The focus was on optimization of operational parameters such as real-time behavior (variable waveforms within a time domain), efficiency, and the voltage/current ripples. The approach was compared to real-time operation and efficiency performance was evaluated showing the accuracy and suitability of the presented approach. The results show the potential for developing complex smart grid simulation models, with a high level of accuracy, and thus the possibility to investigate various operational scenarios and the impact of power converter characteristics on the performance of a smart gird. Two possible operational scenarios of the proposed smart grid concept are evaluated and demonstrate that an accurate hardware-in-the-loop (HIL) system can be designed.

Highlights

Global electricity consumption has been rising from year to year, and the current distribution system is no longer adequately covering the consumption and other requirements of energy consumers, mainly in densely populated agglomerations, or in built-up industrial zones, where many large energy consumers are concentrated
The accuracy of the proposed simulation approach is verified through experimental measurements, whereby the relative error is calculated for the case of bidirectional converters
On the basis of our results, we have confirmed that even with the use of linearized approximated models, high accuracy of simulation results can be achieved as compared with experimental measurements

Summary

Introduction

Global electricity consumption has been rising from year to year, and the current distribution system is no longer adequately covering the consumption and other requirements of energy consumers, mainly in densely populated agglomerations, or in built-up industrial zones, where many large energy consumers are concentrated. If the network limits are exceeded, in extreme cases, the power supply is interrupted a so-called distribution system “blackout”. The solution to this problem could be a new generation network, i.e., a “smart grid” [1,2,3,4]. More and more governments, environmental activists, and other environmental organizations are pushing for the use of green renewable energy sources (RES). The last European Union strategy “Energy 2020” directive stipulated a 20% decrease in CO2 emissions, a 20% increase in the use of renewable sources, and a 20% increase in energy efficiency by 2020 [5,6,7,8,9]. The member states are already on track to meet the greenhouse emissions reduction target for 2020, while the forward plan is to cut emissions by at least 55% by 2030 [10]

Results

Discussion

Conclusion