Microgrid Operation for a Low Voltage Network with
Renewable Energy Sources for Losses Minimisation
and Voltage Control
M. Z.C. Wanik, A. A. Ibrahim,
Dept. of Electrical, Electronics and System Engineering
Universiti Kebangsaan Malaysia
Bangi, Malaysia
mzamri@ukm.edu.my
H. Shareef, T. J. Huat,
Transmission & Distribution Unit
TNB Research Malaysia
Bangi, Malaysia
hussain.shareef@tnbr.com.my
Abstract— This paper present brief description of a Microgrid
development project currently in progress. Initially, then
Malaysian renewable energy policy is briefly highlighted. The
objective of having Microgrid is discussed. The main
components of Microgrid and the technique on how the
Microgrid central controller was developed is also explained.
The result from simulation study of Microgrid system in the
project is presented to demonstrate the workability of the
concept. The modeling and simulation is performed in
DIgSILENT and MATLAB/SIMPOWERSYSTEM software.
The simulation shows quite promising results. The Microgrid
controller managed to control the voltage and frequency in both
grid connected and islanding mode as well as maintained them
within mandatory operational limit of respective operation code
in Malaysia. An active power loss is also significantly reduced.
Index Terms-- Microgrid, renewable energy, distributed
generation, coordinated voltage control.
I. INTRODUCTION
In Malaysia, integration of renewable energy (RE)
resources into electrical grid is increasing substantially due to
encouraging government policy and very attractive incentive.
The government RE targeted that by 2020 is 11 % of
Malaysian electricity generation mix is as depicted in Fig. 1.
This percentage is targeted to increase exponentially (17% in
2030 and 73% in 2050) to support the Malaysian sustainable
economic growth in the future [1-2].
Large amount of the RE as distributed generation (DG)
however is expected to create challenges to power system
operation due to variability of these resources. Thus, in
response to these challenges, a new paradigm in operating
power system with the significant presence of RE is
proposedtp adopt.. In this new paradigm, a part of distribution
network comprises of RE generators is suggested to be
operated as a Microgrid [3-4]. Microgrid can be considered as
a part of technology under Smart Grid to realized active
management of distribution network [5].
Microgrid architectures are being investigated in different
research projects in EU, the USA, and Japan with some
implemented demonstration project. Important components of
a Microgrid include central controller and energy storage.
Different control options and strategies are being investigated
in each of the above projects [3-4]. The factor influencing
these includes energy market scenarios and type of resources
available in those regions. Another important factor is the
local renewable energy policy and incentives provided by the
local government.
Figure 1. Malaysia National Renewable Energy Goals [1]
For example, Microgrid central controller in EU Microgrid
architecture has several control functions that include
optimizing generation and load scheduling based on daily
forecasts and market prices; ensuring that the Microgrid
satisfies the regulations of the distribution network operator;
coordinating between different market agents in the
Microgrid; and supervising islanding operation, load shedding
and restoration, generator blackstart, resynchronization and
system restoration [3-4].
This research works is part of collaboration works between TNB
Research Malaysia and Power System Research Group of Universiti
Kebangsaan Malaysia. TNB (Tenaga Nasional Berhad) is a main electric
utility company in Malaysia and a leading utility company in South East
Asia with almost MYR 87 billion in assets. TNB Research is a research arm
of TNB. The funding is mostly provided by TNB Research.
978-1-4799-8725-2/15/$31.00 ©2015 IEEE