IEEE Electrification Magazine - March 2015 - 82

Banner, an administrative region in far northeastern Inner
Mongolia; one at the Taiping Forestry Center, southeast of
Xi'an in central China; and another focused on PV generation in the Ali Prefecture of Tibet.
In addition to the aforementioned demonstrations,
tens of microgrid standards have already been proposed
since 2011, and some will be published soon. The goals of
the current five-year plan include more than 30 microgrid
demonstrations to be supported by various subsidies and
tariff policies.
The Asia 1 session started with Chengshan Wang's presentation on economic analysis and policy proposals for
island microgrids. Wang analyzed the economic performance of the planned Dawanshan island microgrid,
which has an 850-kW wind turbine, a total of 200 kW of
PV arrays, a 2-MWh lead-acid battery bank, and two 500-kW
diesel generators. To achieve affordable prices, public subsidies of 70% of the initial investment and, for ten years,
US$0.065/kWh on the electricity price were proposed to
encourage more stakeholders to participate in construction and operation. The system
should provide integrated energy service to satisfy residents' demand for
electricity, heating, and cooling as
well as improve overall energy efficiency. Double subsidies to device
manufacturers were encouraged, especially to ones producing both wind turbines and batteries.
Liuchen Chang from the University
of New Brunswick, Canada, reported
an economic and design case study of
an industrial microgrid with PV, a
demonstration project being codeveloped by Guangdong East Power Company and Hefei University of Technology. Analyzing actual PV production
data, he concluded that a control strategy without grid backfeeding may give
rise to significant PV power dumping. An optimized backfeeding microgrid with small-scale PV arrays and batteries
could deliver much higher economic and emission-reduction benefits. A sensitivity analysis of various parameters
and sites for the microgrid showed that government subsidies for initial investment and a feed-in tariff significantly
improve economic results.
Xisheng Tang of the Chinese Academy of Science outlined the status of dc microgrid RD&D, including stability
analysis, simulations, planning, flexible dc converters,
energy management, and dc breakers. Results are being
confirmed at the test dc microgrid constructed at Yanqing, China.
Bo Zhao described the project at the UNESCO Man and
the Biosphere Reserve on Nanji island, a project supported
by the Chinese Ministry of Science and Technology. A vivid
video on this spectacular demonstration site showed that

a flexible structure of multiple microgrids involving green
energy, electric vehicles (EVs), smart meters, and end-use
interaction can form an iconic clean-integrated smart
energy island with high reliability and a nontraditional
energy penetration of more than 55%.
Technical tour participants were impressed by the
facilities visited. For example, Tianjin University's
Microgrid Lab was described by Nikos Hatziargyriou as
"the most complete and best equipped smart grid laboratory I have visited so far, at least within a university."

asia 2 Session
The Asia 2 session included updates from the Asia and
Oceania region; however, this year's session fittingly had a
strong Chinese influence. In a spillover of updates from
China, Nian Liu, from the School of Electrical and Electronic Engineering at the North China Electric Power University
(NCEPU) spoke about how commercial building microgrids
can be used to integrate EV charging and distributed PV
generation to provide both economic and environmental
benefits. The study, which was tested
using the laboratory platform at
NCEPU, looked at different EV charging strategies and showed how a heuristic strategy can be implemented
using an embedded system.
In an update from Korea, BoHyung Cho from Seoul National University presented on the Korea Micro
Energy Grid or K-MEG, which is a dc
microgrid project at his campus. The
presentation covered the advantages
of dc distribution systems (DSs) as an
alternative to ac systems, such as better system efficiency, elimination of
ac power quality problems, and ease
of renewable and energy-storage integration. He described in some detail
the dc protection schemes used in the
K-MEG campus project completed in September 2014.
Judging by the number of questions and comments during
the Q&A session, the project attracted significant interest
among the audience.
The third presentation was on the Energy Technology
Development and Demonstration Program Sino-Danish project and gave an overview of a cross-border collaboration
between Denmark and China on microgrid technology
RD&D. Presented jointly by Josep Guerrero from Aalborg University and Kai Sun from Tsinghua University, the project
was the successful conclusion of the Sino-Danish Renewable
Energy Development (RED) Program, which explored test
problems derived from microgrid operation and hardwarein-the-loop initial tests. The results will be used as a springboard for further joint research. The RED project is a 200-kW
microgrid based on a hybrid wind-PV-storage system. The
main partners include Aalborg University and Kamstrup A/S

An optimized
backfeeding
microgrid with smallscale PV arrays and
batteries could
deliver much higher
economic and
emission-reduction
benefits.

I E E E E l e c t r i f i c ati o n M agaz ine / March 2015

Table of Contents for the Digital Edition of IEEE Electrification Magazine - March 2015