APPLICATION OF SCADA FORSYSTEM
AUTOMATION ON SMART GRID
EEE 818: POWER SYSTEM CONTROL TERM PAPER
APRIL2020
Ezechukwu Kalu Ukiwe
No: 191234011
Dept. of Elect/Elect Engineering
Nile University of Nigeria,Abuja
Olushola EmmanuelAkintola
No: 191234015
Dept. of Elect/Elect Engineering
Nile University of Nigeria,Abuja
Engr. Prof. M. S. Haruna (PhD)
(FAEng, FNSE, FIET, FNATE,
FSESN, CEng)
SUBMITTED BY LECTURER

ABSTRACT
The Application of Supervisory Control and Data Acquisition (SCADA) for system automation on Smart
Grid remains the focus of experts in the power sector and beyond.
Such deployments have been found to improve most system performance metrics, reliability, security,
economy and flexibility to meet ever changing characteristics of the power grid.
The additional techno-commercial requirements of functional smart grid means that a robust monitoring,
control and data acquisition tool like SCADA will always take center stage for any planning and
implementation of system automation over a smart grid.
This paper highlights key features / functionalities of SCADA system and its imperative for ensuring
wholesome automation and network integrity of Smart Grids.

The Supervisory Control and Data Acquisition unit remains one of the fundamental components of the modern power system. It
is critical part of any Energy management system and serves as the engine that drives all other components of the system.
Whether it is generation, transmission and distribution of electricity the role of SCADA cannot be wished away in the traditional
power network, let alone in a Smart Grid. As the glue that binds all the power value chain together, SCADA systems will
continue to redefine and raise the thresholds for efficiency in power system operation, protection and control. The role of
SCADA will continue to predominate as long as the challenge of electricity storage remains; constraints in power generation,
transmission and distribution poses risk in balancing electricity generated with power demand.
The imperative of SCADA is further reinforced by the continuous growth and complexity of the Smart Grid which imposes
additional requirements not only for the utility companies but also for the users of electricity.
For instance in a stand-alone power captive power plant, the generation and consumption of electricity is localized. Such that not
only that the power system parameters are closely monitored but the load can easily be predicted right to the smallest item.
Contrast this with a large interconnected grid with many active and reactive components spread over thousands kilometers in a
country, continent or even across different regions of the world – in this situation many generation units and loads cannot be
effectively predicted. Moreover the health of the power transmission and distribution lines cannot be guaranteed, hence the need
to continuously monitor the status of all elements in the network and configure them to respond to changing operational system
dynamics. For the passive large interconnected grids the challenge of monitoring and control will be huge; but monumental for
Smart grids with lots of distributed generation capacity and bidirectional power flow.
INTRODUCTION

The objectives of this paper are:
• Highlight the dynamics of the Automated Smart Grid
• Restate the key functions of SCADA deployed on a Smart Grid
• Propose a SCADA application for system Automation on a SMART Grid.
OBJECTIVES

• SCADA as the name implies is a system that provides real-time monitoring of power systems in order to
effect proper control, protection and sustainability of the system through the use of sophisticated
computing and communication mechanisms.
• These are accomplished by continuous measurement of power system parameters at any point on the
network. By tradition, the SCADA system is implemented from a central control station via computer
based software application which aids in the automation of the extensive monitoring of network
operations, load dispatching, load and frequency control, load shedding, optimum loading of various
plants and remote back-up protection.
• According to ABB, “smart grid is an evolved grid system that manages electricity demand in a
Sustainable, Reliable and Economic manner, built on advanced infrastructure and tuned to facilitate the
integration of all involved”.
• Whereas, Electric Power Research Institute (EPRI) envisioned the “Smart Grid as one that incorporates
information and communications technology into every aspect of electricity generation, delivery and
consumption in order to minimize environmental impact, enhance markets, improve reliability and
service, and reduce costs and improve efficiency”.
IMPORTANT DEFINITIONS

SMART GRID
Smart Grid Characteristics
1.Self-Healing: Capability to rapidly detect, analyze, respond, and restore from the fault and failures
2. Consumer friendly: Ability to involve a consumer into the decision process of electrical power grid
3. High reliability and power quality: Ability to provide continuous power to satisfy consumer needs resistance
to Cyber-attacks: Ability to be immune and to protect the system from any cyber and physical attacks
4. Accommodate all generation and storage options: Ability to adapt to a large number of diverse distributed
generation (e.g., renewable energy) and storage devices deployed to complement the large power generating
plants.
5. Optimization of Asset and Operation: Ability to monitor and optimize the capital assets by minimizing
operation and maintenance expenses
6. Enables markets: Offers new consumer choices such as green power product and new generation of electric
vehicle which leads to reduction in transmission congestion.

SMART GRID

POWER SYSTEM DATA ACQUISITION AND CONTROL
A SCADA system consists of a master station that communicates with remote terminal units
(RTUs) for the purpose of allowing operators to observe and control physical plants.
RTUs transmit device status and measurements to, and receive control commands and setpoint data from, the master station.
Communication is generally via dedicated circuits operating in the range of 600 to 4800 bits/s with the RTU responding to periodic
requests initiated from the master station (polling) every 2 to 10 s, depending on the criticality of the data.
SCADAFUNCTIONS
• The traditional functions of SCADA systems are summarized:
• Data acquisition: Provides telemetered measurements and status information to operator.
• Supervisory control: Allows operator to remotely control devices, e.g., open and close
circuit breakers. A “select before operate” procedure is used for greater safety.
• Tagging: Identifies a device as subject to specific operating restrictions and prevents unauthorized operation.
• Alarms: Inform operator of unplanned events and undesirable operating conditions. Alarms are sorted by criticality, area of
responsibility, and chronology. Acknowledgment may be required.
• Logging: Logs all operator entry, all alarms, and selected information.
• Load shed: Provides both automatic and operator-initiated tripping of load in response to system emergencies.
• Trending: Plots measurements on selected time scales.

BASIC SCADA FUNCTIONS:
a) Manage communication circuit configuration
b) Downline load RTU files
c) Maintain scan tables and perform polling
d) Check and correct message errors
e) Convert to engineering units
f) Detect status and measurement changes
g) Monitor abnormal and out-of-limit conditions
h) Log and time-tag sequence of events
i) Detect and annunciate alarms
j) Respond to operator requests to: Display information Enter data
k) Execute control action
l) Acknowledge alarms
m) Transmit control action to RTUs
n) Inhibit unauthorized actions o) Maintain historical files
o) Log events and prepare reports
p) Perform load shedding

SCADA OPERATIONS
Operation Supervision Data acquisition & presentation of quantities such as power, voltage current, temperature, water level as
well as fault signals and breaker position. Monitoring of limit values. Acquisition of metered energy
values. Following up of power balance with interconnected utilities and between own regions. Following
up of production and load within different regions. Calculation of spinning reserves. The monitoring of
limit values can be carried out as a function of time and ambient temperature network modeling. Filtering
of measured values. Calculation of non-measured values and transmission losses. Contingency analysis
of theconsequencesof disconnectionof a line of generating set.ShortCircuit calculations
Operational Control Start/Stop of generating sets.On/Off operation of breakers and disconnectors.Hand/Auto for local
automation equipment.Increase/Decreaseof set-point control for power generation voltages gate positions.
Planning(Timehorizon<1 week) Power balance planning with operation schedules. Load prediction, Economic production, distribution between
generating sets, planning of power exchange (Purchase-Sale-Analysis). Simulation operation schedules with
respect to load distribution, economicproduction distribution and security.
Following-up Daily, Weekly and monthly logs for generation, load power exchange and power flow. Even reports in power
systems and control center. Hydrological following up through calculation of head losses, heads, heads, water
flow and spillage statistics.Compilation (calculation) of transmission losses.

ACTIVITIES OF CONTROL CENTER AT DIFFERENT LEVELS
Level Planning Operation Following up
National Control
Center
Load prediction & generation
schedules, power balance planning co-
ordination of overhauls, planning of
reverses
Supervision of load generation, power
exchange reserves, transmission networks,
Tile-line loading and exchange
Reporting and accounting, static,
following up of efficiency, fault
analysis
ZonalControl Center Load prediction and generation
schedules, power balance planning co-
ordination of overhauls, planning
reserves
Supervision of load generation, power
exchange, reserves, transmissionnetworks
Reporting and accounting, static,
following up of efficiency, fault
analysis
District Control Center Short term according to directives Supervision of load, generation, and power
exchange supervision of different
components in power system, operation and
control of underlying power station and
sub-stations
Load generation and
water flow reports,
accountingdata statistics
PowerStation,
Substation Control
Room
Work Planning Control of power, level, etc., sequential
Start/Stop functions, auto system
restoration, protective functions, supervision
of process variables
Sequential events recording

Includes:
− Data collection equipment
− Data transmission telemetry equipment
− Data monitoring equipment
− Man/machine interface
• The Telemetry equipment indicates or records quantities at a location remote from the point.
• Tele-control also means remote control of equipment.
• The telemetering system consists of electronic equipment which converts the data received from
transducers into analogue or digital signals and transmits it to the control room for computing
systems.
SCADA EQUIPMENT FOR SMART GRID

The chosen method will depend among others on network condition and requirement. The following
communication infrastructure have been useful over the years for maintaining information flow needed for
monitoring power network:
a)
b)
c)
d)
Use of telephone lines
Use of separate cables
Power Line Carrier
Radio Wave (Microwave) channels
But the need for very high speed communication in a smart grid means that some of these methods cannot meet
the requirement of smart grid. On the component side, the choice of telecontrol equipment depends on:
1. Kind of information to be transmitted
2. Quantity of information therein
3. Available transmission channels
4. Degree of security demanded
5. Level of accuracy required or tolerance for loss of information
While SCADA have found large scale use in the power generation and transmission segment of the chain, its
limited deployment on most distribution networks across the world continue to pose serious challenge even to
the traditional passive power grid. Whereas, it is at this portion of the power value chain that SCADA will play
the greatest role in a smart grid. This is largely due to the myriad of operational requirements, complexity,
reliability, safety, etc. need for a truly smart network.
METHODS OF DATA TRANSMISSION OF SCADA IN SMARTGRID

PICTORIAL REPRESENTATION OFA SMART GRID (with embedded SCADA System)

Grid Analytics enabled SCADA systems will have the following impact when
deployed appropriately:
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(vii)
(viii)
Detect, remove hazards fast
Fix Transient and Power Quality issues
Monitor asset condition
Planned Maintenance
Track flow by feeder / lateral / span
Identify faults, fix cause – not symptoms
Current direction, DG harmonics
Identify opportunities, monitor impact
SCADA – with Grid Analytics Functionality

• Such SCADA systems not only monitor grid events, they can also monitor the condition of grid assets, such as wires,
switches, and transformers; which would inadvertently ensure better lifecycle management of the smart grid.
• Moreover, SCADA systems running Grid analytics will serve to lower Operations & Maintenance (O&M) costs by
swapping costly and inconvenient emergency maintenance with planned maintenance which can easily be
accomplished more cost effectively, with resulting higher customer satisfaction due in part to fewer power disruptions.
• In order to operate a bidirectional grid in the most acceptable safe manner, SCADA with analytical capability are
needed to set the direction of the current, check presence of harmonics, and address other power quality issues.
Because, a dearth of such analytical system, it is hard to trace how and where power is actually flowing.
• This scenario makes it increasingly difficult to know the best places to site additional distributed generation system.
Where power flow is not well tracked by feeder and by lateral, there will be no data to provide DG project developers
interested in building more generation in a given location, since utilities are not sure of what the real power flows are,
and whether or not additional generation actually creates additional value, as envisaged.
• If a feeder has no distributed generation whatsoever, and significant power is injected into that feeder, most of the time
the utility will be able to adequately compensate the DG provider.
• On the other hand, if a feeder that is already producing more power than the feeder itself needs, then it becomes more
of a challenge to the utility, because it now needs to put in new protective equipment to manage the additional power
that may have no additional value.
…SCADA – with Grid Analytics Functionality (contd.)

• The most efficient way to deploy a SCADA enabled
analytical system is through the decentralized
approach which maximizes the amount of
information gathered in the field while minimizing
the quantum of transmitted data as shown in fig. 4
below.
• When it comes to monitoring and control, the power industry has long
tended to accept a significant disparity between the two sides of the
electrical Grid. On one hand, high-voltage transmission is provided
primarily through highly available meshed networks, and is highly
automated and monitored through
• On the other side of the grid, distribution circuits are predominantly radial
and have very limited monitoring and control. Although Substation
Automation is prevalent in most distribution substations as well as
Distribution Automation at strategic points on distribution circuits, remote
monitoring and control is typically less than ~10% of all of the protective
and sectionalizing devices on main feeder lines
Impact of SCADA with Analytic Functionality

CONCLUSION
The critical challenge of SCADA for System Automation on the Smart Grid will center on knowing where
SCADA analytics will create the most value in a Smart Grid.
Without good data from the system, it is hard to determine what innovation will have the most impact.
For example, if a new type of DG is put on a network; good monitoring of power flows and good resolution
on that network is required, or else the DG’s effects cannot be ascertained.
Effective Grid analytics require that grid data be provided by intelligent sensors; effective access to the data
which is a function of data communications technology; and analytics technology, which comes in the form
of software applications.

REFERENCES
1) Dusit Niyato et al., “Smart grid sensor data collection, communication, and networking: a tutorial”, Wireless
2) Communications and Mobile Computing (2014); 14:1055–1087 Wiley Online Library
3) Sunil S. Rao, “Switchgear Protection and Power Systems, Theory Practice & Solved Problems”, (2016), Khanna
Publishers, New Delhi, india
4) Morteza Shabanzadeh and Mohsen Parsa Moghaddam, “What is the Smart Grid? Definitions, Perspectives, and
Ultimate Goals”, (2013) 28th Power System Conference, Tehran, Iran
5) Mohammed S. Haruna, “Electrical Power System Operation and Control Lecture Notes”, Nile University of
Nigeria, (2020), Abuja Nigeria
6) Michael Bauer, “New Technologies Enabling Grid Analytics -
Whitepaper”, (2016), Sentient Energy Inc., USA

THANK YOU