ABSTRACT:
There is a growing interest in using DC
power systems and microgrids for our electricity transmission and distribution,
particularly with the increasing penetration of photovoltaic power systems.
This paper presents an electric active suspension technology known as the DC
electric springs for voltage stabilization and power quality improvement. The
basic operating modes and characteristic of a DC electric spring with different
types of serially-connected non-critical loads will first be introduced. Then,
the various power delivery issues of the DC power systems, namely bus voltage
variation, voltage droop, system fault, and harmonics, are briefly described.
The operating limits of a DC electric spring in a DC power grid is studied. It is
demonstrated that the aforementioned issues can be mitigated using the proposed
DC electric spring technology. Experiment results are provided to verify the
feasibility of the proposed technology.
KEYWORDS:
1. Smart load
2. Distributed power systems
3. Power electronics
4. Electric springs
5. DC grids
6. Smart grid
SOFTWARE: MATLAB/SIMULINK
Fig.
1. The basic configuration of DC electric springs.
Fig.
2. Enlarged experiment waveforms based on the raw data exported from the oscilloscope
corresponding
Fig.
3. Enlarged experiment waveforms based on the raw data exported from the
oscilloscope corresponding
CONCLUSION:
In this paper, the concept of DC
electric springs (ES) is firstly introduced to cope with several issues of DC
power grids. The DC-ES is proposed as an active suspension system. Similar to
their AC counterparts, the DC-ES can provide dynamic voltage regulation for the
DC bus. The DC-ES connected in series with different types of non-critical
loads to form a smart load have been analyzed and their operating modes have
been identified and explained. Furthermore, the operating limits of the DC-ES
under a given set of system parameters is studied, which provides quantitative
analytical procedures to estimate the theoretical limits of ES. The paper provides
a fundamental study on the DC-ES including the characteristics, the modes of
operation, and the operating limits. The theoretical analysis and the
performance of the DCES have been practically verified.
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