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Smart Grid Management & Visualization
Smart Power Management System
Grace Q. Tang

Graheroce International Corporation
Toronto, Canada



Abstract— This paper presents an innovation Smart Power
Management System on Smart Grid. This report consists of 5
major sections: smart power system modeling; real time power
system monitoring; system engineering database collection and
management; grid condition checking and maintenance; smart
grid power system fault analysis. Smart Power Management
System enables grid management and visualization to be very
effective as it incorporates real time monitoring data and historic
engineering data into an integrated system, analyzing scenarios
based on various modules and making it possible to collect,
monitor and control real time data with accuracy. Smart Power
Management System modeling is based on a variety of factors
according to regulation policies, grid management requirements
and operation rules. Various scenario modules of Smart Power
Management System can be developed and modified based on the
client’s specifications for its grid conditions and operation needs.
Neural Networks adds an interesting flavor of intelligent
modeling to this integrated system, which provides the most
appropriate solution to solve important issues in power system
engineering, system design, grid operation, maintenance and
management. Intelligent functions of Smart Power Management
System can also be modified via wireless channels to cell phones
or other mobile devices for maintenance staff. Real time signals
of abnormal system indications can be sent out to field
maintenance and grid operation as required. Needleless to say,
Smart Power Management System makes it possible that all
desired functions can be integrated so as to support complete
automation control for un-manned power system substations in
the future, to monitor real time system information, to update
real time system data, to identify grid weakness points, to help
field maintenance keep power system facilities in a good working
condition, to conduct power systems fault analysis and operator
training, to effectively support field maintenance, system
troubleshooting and repair and to provide emergency
contingencies to power system maintenance, operations, control
centers for smart grid management and visualization.
Keywords- Smart grid; management; powe system; modeling;
real time; analysis; data collection; visualisation; aumotmation;
control; maintenance; Neural Networks. (key words)

I. INTRODUCTION

Smart Power Management System is an innovation for grid
management and visualization, to monitor real time system
information, to capture and update engineering data, to identify
grid weakness point, to effectively support power systems fault
analysis, field maintenance, troubleshooting and repair as well
as to provide emergency contingency solutions for Smart Grid.
II. BACKGROUND

The massive electric power blackout in the northeastern US
and Canada on August 14–15, 2003 catalyzed discussions
about modernizing the US electricity grid. Industry sources
suggested that investments of $50–100 billion would be
needed. The importance of power system reliability and Smart
Grid are now on the top of the to-do list of many power
utilities.
The August 14, 2003 blackout in Ontario and much of the
U.S. Mid West and North East has highly raised awareness of
the electricity system, as 50 million citizens simultaneously
experienced firsthand how vital electricity is in our day-to-day
lives. The blackout has added a sense of urgency to the
discussion already underway on the need for measures to
ensure reliability in the electricity industry.
How to make power system more reliable? What do we do
so that we can have the most appropriate performance for
power grid control and management and reduce costs at the
same time? Smart Power Management System is the
innovation solution for Smart Grid, as it adds monitoring,
analyzing, controlling and communication capabilities up to
grid management for power generation, transmission and
distribution at every level of the system.
In the U.S. and Canada, bills have been passed nationally
and at the state level to mandate renewable energy standards,
funded by both government and industry.
Smart Power Management System focuses on new
technology in power systems and greatly supports grid’s
reliability and security under this situation, working with
Digital relays, fiber-optic telecommunication, wireless
communication, SCADA, SER, DFR, AMI, GIS, GPS, cyber
security interface, etc. while collaborating with different
preferences and needs for Smart Grid. Smart grid standards and
technologies are incorporated in Smart Power Management
System so as to save power utility time and money.

III. SMART POWER MANAGEMENT SYSTEM
Smart Power Management System enables grid management
and visualization to be very effective as it incorporates real
978-1-4577-1591-4/11/$26.00 ©2011 IEEE


time monitoring data and historic engineering data into an
integrated system, analyzing scenarios based on various
modules and making it possible to collect, monitor and control
real time data with accuracy. Smart Power Management
System data collections include real time information from:

SCADA (supervisory control and data acquisition
system)
EMS (energy management system)
DMS (distribution management system)
GIS (geographic information system)
SER (sequence event record system)
DFR (digital fault recorder system)
Smart metering data
Operation event data
Power quality ( voltage, Frequency)
Protection system fault data (fault currents, voltages,
phase angles…etc.)
Asset management data
Demand response
Power system operation
Operator training
Station maintenance data
Engineering data

The design of Smart Power Management System is based
on the following aspects of system interface:
Home Energy Management
Building Energy Management
Grid Interconnect
In recent years, we have seen several catastrophic power
system blackout events throughout the world and the usual
cause is that the power system is in a stressed state, followed
by faults on critical facilities or old equipment. Every time
when power system has a fault or an outage, protection and
control systems – relays and related automation systems play
an important role in all those events. Every single circuit of
power grid has numerous relays to control its behavior (i.e.,
opening or closing the circuit, sending signals to control
centre, transferring trips to other power grid transmission line,
etc.). The estimated number of relays in service in North
America grid is more than 5 million. The major function of
relays is to trip associated circuit breakers which are
connected to generators, transmission lines, distribution lines,
transformers, buses, etc., in response to faults or other
conditions for which the protection and control system is
designed.



Figure 1. Smart Power Management System

According to the thorough studies on many major captured
power system fault events/blackouts, the results of power
system performance fell into four categories:

Correct and appropriate (System operated correctly
and achieved desired results as designed.)
Correct and inappropriate (System operated correctly
as designed but the result was not what was
intended.)
Incorrect and appropriate (System operated
incorrectly but this prevented another more severe
trip and avoided a major cascading failure.)
Incorrect and inappropriate (System operated
incorrectly and this contributed to a cascading outage
– this is also a serious mis-operation.)

Therefore, the first consideration is to check and ensure
protection and control systems operate as designed and
function correctly. Smart Power Management System collects,
sorts out and compares real time data, to ensure there is no
conflicting information which is quite common due to the gaps
among grid functioning bodies. For example, how many times
does one breaker tripped and what is the estimated
replacement time? When there are two protection schemes
have conflicts, which one would be the best from the grid
management perspective? We do not need to wait until fault
happens to evaluate any undesired outcomes; we can do it now
so as to minimize any unwanted outages and reduce the grid
stresses for smart grid management.

Smart Power Management System mak
Based on various system scenarios, all the d
and analyzed to provide the most reliable r
operations to handle abnormal system situa
optimal performance.


Figure 2. Power system fault demonstration

The major power system fault types as follo
One phase to Neutral
Phase to phase
Two phase to Neural
Three phase
One phase on the Ground
Two phase on the Ground
Three phase on the Ground
Other types of faults include one-conducto
conductors-open. As in the case of balanced th
unsymmetrical faults have two components o
an ac or symmetrical component, includi
transient, and steady-state currents and a
Complex power system faults typically a
combinations of those above faults. Accord
types, we consider major challenges and pos
in order to prioritize tasks for each module. F
system fault currents, we have the following c

Phase-to-ground fault:

Ia=
RF Z Z Z
VAN
+ + + 3 / ) 0 2 1 (
Ib=Ic (A p

63
11%
2%
2%
15%
2%
1% 4%
One Phase to Neutral
Phase to Phase
Two Phase to Neutral
Three Phase
One Phase on the Ground
Two Phase on the Ground
Three Phase on the Ground
Other


es this possible.
data is integrated
results to enable
ations and reach

ows:
or-open and two-
hree phase faults,
of fault currents:
ing subtransient,
dc component.
are the various
ding to the fault
sibility scenarios
For typical power
calculations:
hase to ground)
Ib=
RF Z Z Z
VBN
+ + + 3 / ) 0 2 1 (

Ic=
RF Z Z Z
VCN
+ + + 3 / ) 0 2 1 (
I

Phase-to-phase

Ia=-Ib= - j
RF Z Z
VLN
+ + 2 1
3
Ic = 0


Ib=-Ic= - j
RF Z Z
VLN
+ + 2 1
3
Ia=0 (

Ic=-Ia= - j
RF Z Z
VLN
+ + 2 1
3
Ib=0 (

Three-phase f

IN=
R Z
VLN
+ 1

Phase-to-phase-to-g

Ia= -j 3 VLN
Z Z Z
Z Z
) 0 2 1 ( 1
1 0
+
−α
ground fau

Ib= j 3
Z Z
Z
2 1 ( 1
0
+
−α
Ic=
2 1 ( Z Z
VLN
+


Ib= -j 3 VLN
Z Z Z
Z Z
) 0 2 1 ( 1
1 0
+
−α
ground fau

Ic= j 3
Z Z
Z
2 1 ( 1
0
2
+
−α
Ia=
2 1 ( Z Z
VLN
+

Ic= -j 3 VLN
Z Z Z
Z Z
) 0 2 1 ( 1
1 0
+
−α
ground fau

3%
Ia=Ic (B phase to ground)
c= Ib (C phase to ground)
e fault:
0(A-B phase-to-phase fault)
(B-C phase-to-phase fault)
(C-A phase-to-phase fault)
fault:
RF
N

ground fault
(A-B phase-to-phase-to-
ult)
VLN
Z
Z
) 0 2
1
2

3 / ) 0
N

(B-C phase-to-phase-to-
ult)
VLN
Z
Z
) 0 2
1
2

3 / ) 0
N

(C-A phase-to-phase-to-
ult)
Ia= j 3 VLN
Z Z Z
Z Z
) 0 2 1 ( 1
1 0
2
+
−α
Ib=
3 / ) 0 2 1 ( Z Z
VLN
+



Ia: A phase current
Ib: B phase current
Ic: C phase current
VLN: faulted line to ground volt
Z1: positive-sequence impedan
Z0: zero-sequence impedance
ZG: neutral reactor impedance
RF: fault resistor impedance

For a typical Line-to-Line fault, for examp
fault from phase b to c, here we include fault i
generality; we have the following fault con
domain:

Ia=0
Ib= - Ic
Vbg-Vcg = Zf Ib

Ia: A phase current
Ib: B phase current
Ic: C phase current
Vbg: B phase to ground vo
Vcg: C phase to ground vo
Zf: fault impedance

In sequence domain, we have

I0=0
I2= - I1
(V2-V1)= Zf I1

I1: positive-sequence curre
I2: negative-sequence curr
I0: zero-sequence current
V1: positive-sequence volt
V2: negative-sequence volt

To demonstrate one scenario of this stud
above Line-to-Line fault from phase b to c a

1) To measure 6 parameters: Ia, Ib, Ic, V

2) To compare the absolute value of Ia,
two current measurements are equal,
for the stamp; if any two current elem
equal, then we use 0 for the stamp.

As we know, for interconnected sequenc
have the following:



N
tage
nce
e
e

ple, Line-to-Line
impedance Zf for
ndition in phase
oltage
oltage
ent
rent
tage
tage
dy, we use the
as an example.
Va, Vb, Vc.
Ib and Ic, if any
then we use 1
ments are not

ce networks, we
_
Iu
I1
I2
_ =
1
3
_
1 1 1
1 o o
2
1 o
2
o
_ _
u
Ib
-Ib
_

Thus, we can develop a matrix

to indicate the status of the measure
use Ia, Ib and Ic as references, we ha











1 1 0
1 1 0
1 0 1


Combining the developed
power system sequence matrixes
Power Management System mode
calculation modules have the func
analyzing for power system faults
fault analysis more accurate and mu
adds an interesting flavor of int
integrated system. To simulate
intelligent functions and provide be
also incorporated into operation
operators with operation solution
contingency plans for grid operation




Figure 3. SPM Neural N

Smart Power Management Syst
variety of factors according to
management requirements and
scenario modules of Smart Power M
developed and modified based on
for its grid conditions and operatio
power system operations, field
B ph
Time
= _
u
1¡S(o - o
2
)Ib
1¡S(o
2
- o)Ib
_










cc cb ca
bc bb ba
ac ab aa

ement (absolute value). We
ave the following matrix:

d scenario matrixes with
is one example of Smart
eling philosophy. Build in
ctionality of detecting and
and making power system
uch faster. Neural Networks
telligent modeling to this
the scenarios to achieve
est solutions, this process is
training scenarios to help
ns as well as emergency
n and management.


Networks Logic
tem modeling is based on a
regulation policies, grid
operation rules. Various
Management System can be
the client’s specifications
onal needs so as to support
maintenance, engineering
hase to C phase fault type


design, asset management under normal condition and under
power system disturbance condition as well as to provide
emergency contingencies to make grid management smarter,
faster and more accurate.

The above logic diagram demonstrates the process of
establishing Neural Networks for Smart Power Management
System. Using Neural Networks is to establish a brand new
approach combined with advanced accurate information
collection systems and methods which provide the most
appropriate solution to important issues in power system
engineering, system design, grid operation, maintenance and
management. In addition, intelligent functions of Smart Power
Management System can also be modified via wireless
channels to cell phones or other mobile devices for
maintenance staff and real time signals of abnormal system
indications can be sent out to field maintenance and grid
operation as needed.

A. Reliability

Reliability is always a major concern for protecting power
systems. Smart Power Management System uses new
modeling techniques, to best mimic power system
configurations and charactaristics and properly restrain from
tripping when there is no need to trip wider zones. Its primary
and backup systems are designed to provide dual reliability.

Simultaneously monitoring and analyzing power system in
real time from generation, transmission and distribution, not
only helps power utility companies to better manage their
power grid, but also improves customer services for end users,
and better accommodates energy needs more efficiently and
minimizes or avoids blackouts. Smart grid is much less
vulnerable to deliberate manipulation and attacks with more
accurate and faster information collection, monitoring and
analyses.

Without interrupting current configurations of existing
systems, Smart Power Management System collects, modifies
and analyzes integrated data and produces resolutions. All
information is incorporated at a timely manner to provide most
accurate status on power system configurations and major
changes for power grid, thus increasing the accuracy of system
conditions and maintaining excellent reliability.

B. Dependability

Dependability is the ability for power system to quickly
isolate a fault condition or other unwanted disturbance event
occurred due to weather, equipment failure, environmental
impact, animal contact, human error and other factors. While
security is not improved by increased redundancy,
dependability is. Obviously, the impact on the power system
when a protection device is not functioning correctly when
required is much less severe when there is a redundant device
that takes over the job. If the two redundant devices are of
equal performance, there should be no detrimental effect at all
on power system operations, and a non-functioning device
would just need to be repaired or replaced to ensure correct
performance as required. Smart Power Management System
has dual sub-systems – the primary and the secondary to
ensure correct performance on dependability.

Because most utilities built major power system
infrastructures a long time ago and nowadays many
transformers, equipment and cables are close or exceeded their
normal life cycle time. Due to the cost of replacing them and
lack of manpower to complete the replacement work, many
utilities faced incredible challenges and started to keep those
old facilities in service as long as they can and thus
continuously monitoring and analyzing equipment conditions
becomes crucial.

With timely monitoring and analyzing, Smart Power
Management System makes it possible to indicate problem
areas and defective equipment at an early stage. The status of
asset management condition is also displayed on an LED
screen and real time signals for any abnormal conditions are
sent to field maintenance and operation control centre.

C. Communication

Communication consists of equipment communication,
telecommunication, HMI interface and integrated applications
of software and hardware.
Smart Power Management System incorporates needs
from all equipment communication, telecommunication and
HMI interface and combines the information from remote ends
and local alarm annunciation systems with integrated
functions through wireless communication so that LED screen
can display real time power system information on detected
problems and the information can be shared with SCADA
equipment, Digital Fault Record (DFR) and Sequence Event
Record (SER) systems remotely.
Most recent years, many power utility companies made
great changes on their revenue metering systems to better
serve their customers and avoid incorrect or inconvenient
meter readings. An advanced metering infrastructure (AMI)
will enable consumer-friendly efficiency concepts like “prices
to devices,” under which prices are relayed to “smart” home
controllers or end-consumer devices like thermostats,
washer/dryers, microwave, refrigerators, air conditioner and
other household consumers of power, which process the
information and start or stop devices based on customer
preference. Smart metering becomes more and more involved
in smart grid management.

Thus Smart Power Management System considers smart
metering as a second layer of the system and collects needed


information for its integrated functions while considering
protection and control as the first urgent layer of the system.

D. Redundancy

Protection and control is the “safe guard” of power grid.
For protective relaying system, the preferred method of
meeting reliability requirements has been using physically
separate, redundant protection devices. For example, a pilot
protection scheme consists of relays, communications
interface device and a communications channel. All of these
need to function properly for the protection scheme to operate
as intended. Not only this method is used for protection and
control, but also many protection schems need to be designed
to have overlaped protection zones. Thus protection
coordiantion becomes very sensitive and critical. Smart Power
Management System adjusts overall functions for this need of
Samrt Grid and creates scenarios for the best practice to
coordinate protection and control performance to achieve the
most desired outcomes, therefore, to optimizing overall
operation performance and avoiding power system failures.

E. Stability

Power grid in the United States and around the world have
being facing challenges to plan under deregulation due to
uncertainties on transmission planning, DG connection and
other major factors.

As power system stability is the ability of synchronous
machines to move from one steady-state operating point
following a disturbance to another steady-state operating pint,
without losing synchronism, most power utilities maintain
restoration plans based on company’s restoration objectives,
operating philosophies and good practices. While these plans
have been successfully tested in the past, they can be
improved significantly by simulating steady-state, transient
and dynamic behavior of power system based on Smart Power
Management System developed scenarios to accommodate the
grid needs, including restoration planning, frequency control,
voltage control, generation reactive capability, protection
system issues, estimating restoration duration and operator
training.
F. Effeciency

Smart grid enables more widespread use of distributed
generation: bringing generation closer to consumers. Solar-
powered homes, for example, could buy energy from the grid
at night and sell it back during the day, providing a strong
green incentive for consumers and contributing to a more
robust grid. Smart Power Management System combines real
time information from energy consumers, producers and
distributors with grid real-time information on the cost,
demands and supply of power across the grid, thus enables an
unprecedented level of control at every level of the system.

From the United States Department of the Energy report
named “The Smart Grid: An Estimation of the Energy and
CO2 Benefits”, over the next 20 years, smart grid technology
will become pervasive in the United States because of the cost
efficiencies it provides for the electric power system and that it
could be leveraged to provided additional benefits of reduced
energy consumption and carbon emissions.

Needleless to say, power system has entered a new era and
we need to develop better systems to help us with the demand
of Smart Grid. Smart Power Management System makes it
possible that all desired functions can be integrated nicely so
as to support complete automation control for un-manned
power system substations in the future, to monitor real time
system information, to update real time system data, to
identify grid weakness points, to effectively maintain a good
working condition for power system equipment, to conduct
power systems fault analysis and operator training, to support
field maintenance, system troubleshooting and repair and to
provide emergency contingencies to power system
maintenance, operations, control centers for smart grid
management and visualization.

IV. REFERENCES:

[1] J.Duncan Glover, Mulukutla S. Sarma and Thomas Overbye, Power
System Analysis and Design, Thomson, Pacific Grove, CA, 2008
[2] Q.J.Zhang and K.C.Gupta, Neural Networks for RF and Microwave
Design. Norwood, MA;Artech House, 2000.
[3] P.J.C. Rodrigues, Computer-aided Analysis of Nonlinear Microwave
Circuits, Boston: Artech House, 1998.
[4] S.S.Rao, Engineering Optimization, Theory and Practice, New York:
Wiley, 1996.
[5] Novosel, D. and King, R.L, Identification of power system emergency
actions using neural networks, Proceedings of the First International
Forum on Applications of Neural Networks to Power Systems, 1991.
[6] Cannas, B.; Celli, G.; Marcheshi, M.; Pilo, F., Neural networks for
power system condition monitoring and protection, Neurocomputing, v
23, n 1-3, Dec. 1998.

V. BIOGRAPHIES:

Grace Q. Tang is a registered professional engineer who has more than 18
years excellent working experience with major utilities in North America,
Asia and Fortune 500 companies in the world, including power system
research study & analysis, project design & implementation, engineering &
construction solutions, power system maintenance &operation and power
system professional training. She analyzed hundreds of cases for 13.8kV,
27.6kV, 44kV, 115kV, 230kV and 500kV Transmission & Distribution
system protection and control performance for 2003 North America black out
and provided technical support and recommendations for technical solutions.
She received various rewards for her contributions to the society and also
gives lectures on career development and professional training programs.

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