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On-line Access: 2013-01-03

Received: 2012-08-08

Revision Accepted: 2012-11-01

Crosschecked: 2012-12-23

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Journal of Zhejiang University SCIENCE C 2013 Vol.14 No.1 P.50-64

http://doi.org/10.1631/jzus.C1200236


Analysis, design, and experimental evaluation of power calculation in digital droop-controlled parallel microgrid inverters


Author(s):  Ming-zhi Gao, Min Chen, Cheng Jin, Josep M. Guerrero, Zhao-ming Qian

Affiliation(s):  Department of Applied Electronics, Zhejiang University, Hangzhou 310027, China; more

Corresponding email(s):   calim@zju.edu.cn

Key Words:  Distributed generators, Distributed energy storages, Microgrid, Wireless parallel, Droop control, Digital control system, p-q theory


Ming-zhi Gao, Min Chen, Cheng Jin, Josep M. Guerrero, Zhao-ming Qian. Analysis, design, and experimental evaluation of power calculation in digital droop-controlled parallel microgrid inverters[J]. Journal of Zhejiang University Science C, 2013, 14(1): 50-64.

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author="Ming-zhi Gao, Min Chen, Cheng Jin, Josep M. Guerrero, Zhao-ming Qian",
journal="Journal of Zhejiang University Science C",
volume="14",
number="1",
pages="50-64",
year="2013",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.C1200236"
}

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%T Analysis, design, and experimental evaluation of power calculation in digital droop-controlled parallel microgrid inverters
%A Ming-zhi Gao
%A Min Chen
%A Cheng Jin
%A Josep M. Guerrero
%A Zhao-ming Qian
%J Journal of Zhejiang University SCIENCE C
%V 14
%N 1
%P 50-64
%@ 1869-1951
%D 2013
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.C1200236

TY - JOUR
T1 - Analysis, design, and experimental evaluation of power calculation in digital droop-controlled parallel microgrid inverters
A1 - Ming-zhi Gao
A1 - Min Chen
A1 - Cheng Jin
A1 - Josep M. Guerrero
A1 - Zhao-ming Qian
J0 - Journal of Zhejiang University Science C
VL - 14
IS - 1
SP - 50
EP - 64
%@ 1869-1951
Y1 - 2013
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.C1200236


Abstract: 
Parallel operation of distributed generation is an important topic for microgrids, which can provide a highly reliable electric supply service and good power quality to end customers when the utility is unavailable. However, there is a well-known limitation: the power sharing accuracy between distributed generators in a parallel operation. Frequency and voltage droop is a well-established control method for improving power sharing performance. In this method, the active and reactive power calculations are used to adjust the frequency and amplitude of the output voltage. This paper describes the digital implementation of a droop method, and analyzes the influence of power calculation on droop method performance. According to the analysis, the performance of droop control in a digital control system is limited by the accuracy and speed of the power calculation method. We propose an improved power calculation method based on p-q theory to improve the performance of the droop control method, and we compare our new method with two traditional power calculation methods. Finally, simulation results and experimental results from a three single-phase 1-kW-inverter system are presented, which validate the performance of our proposed method.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

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