These slides present various communications and measurement technology applied for smart grid. Later of the class I will present the same at advance level.

1. Class-5: Smart Grid
Communications Measurement
Technology
Prof. (Dr.) Pravat Kumar Rout
Department of EEE
ITER
Siksha ‘O’ Anusandhan (Deemed to be University),
Bhubaneswar, Odisha, India
1

2. Introduction
• Communications is the enabling technology for Power System
• No single communication technology as being best suited for all power system needs.
• The smart grid is a new generation of standard power distribution grid. The communication
infrastructure is critical for the successful operation of the modern smart grids.
• The smart grid uses two-way communications, digital technologies, advanced sensing
and computing infra structure and software abilities in order to provide improved
monitoring, protection and optimization of all grids components including generation,
transmission, distribution and consumers
2

3. Continue…
• The use of communication technologies ensures the reduction of energy
consumption, optimal operation of the smart grid and coordination between all
smart grids’ components from generation to the end users.
• Existing communication technologies are such as ZigBee, WLAN, cellular
communication, WiMAX, Power Line Communication (PLC), their implementation
in smart grids, advantages and disadvantages.
3

4. 4
Role of Communications

5. Possible Two-way Communications
5

6. 6
Communication Architecture

7. 7
Smart Grid Communication Infrastructure
Three Types of Network: 1: Home Area Network (HAN); 2: Neighbourhood Area
Network (NAN); 3: Wide Area Network ( WAN)

8. Communication Needs of Power System
1. Reliability
2. Cost effectiveness
3. Capacity to handle data rates
4. Adequate to meet response requirements
5. Ability to reach identified areas of power
system
6. Ease of operation and maintenance
7. Security (of data and of control actions)
8

9. Communication Needs of Power
System: 1 Communication Reliability
Reliable communication with respect to:
• Exposure to severe environment
• Electromagnetic Interference (EMI)
• Transient EMI (lightning, faults)
• Outage of transmission lines
• Power outages
• Radio paths obstructed or attenuated (by buildings or foliage) 9

10. Communication Needs of Power
System: 2 Cost Effectiveness
•
• Communication system costs are significant
• High cost of communication system may become an impediment
• Evaluate both first cost and lifetime operation and maintenance
costs
• Look for best trade-off between total costs and overall
performance
10

11. Communication Needs of Power System: 3
Capacity to handle Data Rates
•
• Perform data rate audit of present & upcoming schemes
• Analyze each function
• Determine bit rate required to perform the function
• Consider worst case scenarios
• Each communications system has a bandwidth limit
• There should be at least enough bandwidth along each path to meet
data requirements
• A good margin allows for future growth and increased system
flexibility
11

12. Communication Needs of Power System: 4
Ability to meet response requirements
Response requirements (measured in sec.) are distinct from data rate
requirements (measured in kb/s or Mb/s), and must be met
independently.
Different functions have vastly different requirements for the delivery of
the information; for example:
Function Delivery requirements
Open or close feeder switches 1-2 seconds
Acquire substation status data 2-5 seconds
Acquire feeder measurements 5-10 seconds
Acquire meter data 15 min. – 24 hours and up
12

13. Communication Needs of Power System: 5
Ability to Reach Areas of Power System
• Difficult Terrain
• Communications that rely on the power line may have difficulty
• During outage of line
• Extreme weather conditions
• Terminal equipment in outage areas may require backup power for
long durations
13

14. Communication Needs of Power System: 6
Ease of Operation and Maintenance
• A communications system is a complex combination of transmitters,
receivers, and data links
• Manpower not trained and not familiar with communications equipment
• Personnel trained for new skills involved ?
• New tools acquired ?
• Use standardized components and communication protocols
14

15. Communication Needs of Power System: 7
Security of data and control actions
• Power System communication Data & Voice have critical
importance.
• Communication security is a necessity.
Your substations are an element of the country’s
critical infrastructure – are you sure that you are in
complete control?
Maintaining the security of communications between the control center and field
devices is one of the most urgent problems facing today’s control environment.
15

16. Five Major Characteristics of Smart Grid
Communication Technology
• High Band width
• IP-enabled digital Communication(IPv6 support is preferable)
• Encryption
• Cyber Security
• Support and Quality of Service and Voice over Internet Protocol(VoIP)
16

17. Communication Technologies
Wired Wireless
Power Line Carrier
Communication(PLCC)
Microwave
Dedicated Leased Line VSAT
Optic Fiber Mobile Networks
17

18. 18

19. Communication Technologies: 1 Power Line
Carrier Communication (PLCC)1/10
• Power Lines used for point to point communication. That is it allows data
exchange between devices through electrical power lines.
• Terminal equipments used to send/receive data/voice.
• Works on audio band width 20 to 20 KHz
• Carrier 30 KHz to 500 KHz
• It is a system for carrying data on a conductor.
• Proposed a protocol stack based on IPv6/TCP using low speed PLC
19

20. PLCC….2/10
• It uses the existing power lines to transmit data from one device to another.
• This makes power line communication one of the best means for networking.
• It operates by impressing a modulated carrier signal on the wiring system. Data rates over
a power line communication system vary widely.
• The advantage of the PLC is already established, wide-spread infrastructure that reduces
installation costs.
• The disadvantages are presence of higher harmonics in the power lines that interfere with
communication signals and limited frequency of communication.
20

21. Some control networks in power line
communication 3/10
• CEBUS
• LonWorks
• LnCP
• HNCP
21

22. CEBUS 4/10
• LAN network provides communication between of control information
and services among devices.

23. LonWorks 5/10
• LonWorks consist of all nodes that communicate with one another over
a variety of communications media using LonTalk protocol, a common
message-based communications protocol

24. LnCP 6/10
• A peer-to-peer communication model is used in this network.
• It is a multi-master system

25. HNCP 7/10
• This protocol provides standard message set of devices.
• Has to be compact to enable the use of low-bandwidth network media .
• The range of devices applying this protocol reaches all the electric
machines that are connected by PLC .

26. ◼ Easy availability
◼ Cost effective
◼ Ease of operation & maintenance
PLCC---Pros 8/10
26

27. PLCC--- Cons 9/10
• Limited bandwidth(4 KHz)
• Data speeds up to only 1200 Bauds possible
• Prone to Noise & Interference
• Effect of weather conditions-frost, high pollution etc
• Depends on physical connectivity of power lines
• Needs government approval for carrier freq selection
• Not suitable for today’s needs of automation like SAS, remote control etc.
• Lack of interoperability
• Inadequacy of the regulations for broadband PLC
27

28. 28
A summary of PLC-based SG applications 10/10

29. Communication Technologies: 2: Fiber Optic
Communication 1/5
• Fiber optic cable functions as a "light guide," guiding the light
introduced at one end of the cable through to the other end. The light
source can either be a light-emitting diode (LED) or a laser. Using a lens, the
light pulses are funneled into the fiber-optic medium where they travel down
the cable.
29

30. Continue.. 2/5
• The light (near infrared) is most often are used :
• 850nm for shorter distances
• 1300nm for longer distances on Multi-mode fiber
• 1310-1320nm for single-mode fiber
• 1,500nm is used for longer distances.
30

31. Continue…3/5
• Two types of fibre-
Multi mode > 50micron core– Upto 2 Kms
Single mode < 10 micron core—more than 20 Kms
• Selected on the basis of distance & bandwidth needs
• Wave Division Multiplexing Used
31

32. Fiber Optic Communication… Pros 4/5
• Fast becoming common in utilities for voice and data transmission
• Offer many advantages
• extremely high data transmission rates
• immunity from electromagnetic interference
• Free from licensing requirements
• Cost effective for very high data transmission rates in a point-to-point
configuration
32

33. Fiber Optic Communication… cons 5/5
• Not as cost effective for applications, with
• Point-to-multipoint configuration
• Modest data transmission speed requirements
• Prone to cable cut in underground configuration
• Repair & restoration specialized work
33

34. Communication Technologies: 3: VSAT Communication 1/4
Geo-synchronous satellite
Earth Station
36,000 km
User site 34
VSAT (Very Small Aperture
Terminal) is a satellite
communications system
that serves home and business
users.

35. Continue.. Operation 2/4
• A VSAT end user needs a box that interfaces between the user's
computer and an outside antenna with a transceiver. The transceiver
receives or sends a signal to a satellite transponder in the sky. The satellite
sends and receives signals from an earth station computer that acts as a
hub for the system. Each end user is interconnected with the hub station via
the satellite in a star topology.
• For one end user to communicate with another, each transmission has to
first go to the hub station which retransmits it via the satellite to the other
end user's VSAT.
• VSAT handles data, voice, and video signals.
35

36. VSAT (contd..) 3/4
• Various frequency bands:
• C-band (4/6 GHz), Ku-band (12/14 GHz),Ka-band(30/20 GHz)
• Advantages
• Near-universal coverage
• Good reliability
• Fast installation
• Disadvantages
• Cost
• Transmission delays
• Blackout periods due to eclipses
• Attenuation in heavy rain (Ku band)
36

37. GIS and Google Mapping Tools 4/4
Purpose and uses:
1. GIS is useful for
managing traditional
electric transmission and
distribution and telecom
networks.
2. It can also help to manage
information about utility
assets for data collection
and maintenance.
37
Needs:
1. Reducing outage time
2. Preventing power theft which causes significant unaccounted losses
3. Effective system for collection and billing system
4. Expanding services for customers
5. Effective asset management
6. Improving reliability such as SAIDI (System Average Interruption
Duration Index) and SAIFI (System Average Interruption
Frequency Index) for distribution networks
7. Improving analysis of customer complaint logs
8. Enhancing load flow power quality analysis and fault study for
current and anticipated problems
9. Scheduling of actions such as load shedding and vegetation
control

38. Communication Technologies: 4: Multi-agent
Systems(MAS) Technology 1/4
What is it? And how it works?
MAS are a computational system in
which several agents cooperate to
achieve a desired task.
The performance of MAS can be
decided by the interactions among
various agents.
Agents cooperate to achieve more
than if they act individually.
38

39. Multi-agent Systems for Smart Grid
Implementation 2/4
The multi-agent system is autonomous in that they
operate without human interventions.
The multi-agent system is sociable in that they
interact with other agents via some kind of agent
communication language.
MAS in smart grid has four agents namely:
1: Control agent: Responsibilities include
• Monitoring system voltage and frequency
• Sending signals to the main circuit breaker in case
of upstream outage
• Receiving electricity price ($/kWh) signal from
the main grid and publishing them to the
Intelligent Distributed Autonomous Power
System (IDAPS) entities
39
2: Distributed energy resource (DER) agent:
Responsibilities include
I. Controlling power levels of DER and storing their
data
II. Information about DER include
•Availability and on/off status
•Cost of participation
•Maintenance schedule etc.

40. Continue…..3/4
3: User agent: Responsibilities include
• Acts as a customer gateway between
IDAPS and users
• Providing users with real-time
information on entities residing in the
IDAPS system;
• Monitors electricity consumption by
each critical and noncritical load
• Allows users to control the status of
loads based on user’s predefined priority
40
4: Database agent:
Serves as a data access point for
other agents as well as users
responsibilities include
1. Storing system information
2. Recording messages
3. Data shared among agents.

41. Continue… 4/4
An agent of a MAS may be defined as an entity with
attributes considered useful in a particular domain.
Agent attributes include:
• Autonomy: goal - directedness, proactive and self
- starting behaviour
• Collaborative behaviour: the ability to work with
other agents to achieve a common goal
• Knowledge - level communication ability: the
ability to communicate with other agents with
language resembling human speech acts rather than
typical symbol-level program - to - program
protocols
• Reactivity: the ability to selectively sense and act
• Temporal continuity: persistence of identity and
state over long periods
41
MAS can be characterized by:
• Each agent has incomplete
capabilities to solve a problem
• No global system control
• Decentralized data
• Asynchronous computation

42. Communication Technologies: 5: Cellular
Networks
• They allow high data rate communications up to 100 Mbps. Therefore, the
cellular networks can be used for communication between different components
and devices in smart grid.
• There are several existing technologies for cellular communication such as GSM,
GPRS, 2G, 3G, 4G and WiMAX .
• The WiMAX technology is the most interesting for smart grid implementation. It
is working on 2.5 and 3.5 frequencies, with data exchange rate of 70 Mbs and
coverage up to 50 km.
• The WiMAX chips are integrated inside the smart meters that are deployed
through the smart grid.
42

43. 43

44. 44

45. Continue….
• The advantages of the cellular networks are already existing infrastructure
with wide area of deployment, high rates of data transfer, available security
algorithms that are already implemented in the cellular communication.
• The major disadvantage is that cellular networks are shared with other
users and are not fully dedicated to the smart grid communications. This can
be serious problem in case of emergency state of the grid.
45

46. Communication Technologies: 6: ZigBee 1/4
• ZigBee is based on an IEEE 802.15 standard. ZigBee is used in applications that require
a low data rate, long battery life, low cost and secure networking.
• Applications include wireless light switches, electrical meters with in-home-displays, traffic
management systems, and other consumer and industrial equipment that requires short
range wireless transfer of data at relatively low rates. ZigBee allows connection of up to
60,000 devices to its network.
• ZigBee has a defined rate between 20 to 250 kbs, best suited for periodic or
intermittent data or a single signal transmission from a sensor or input device. The
technology defined by the ZigBee specification is intended to be simpler and less
expensive than other wireless personal area networks (WPANs), such as Bluetooth or Wi-
Fi. ZigBee networks are secured by 128 bit symmetric encryption keys.
46

47. Continue…2/4
• There is a “ZigBee Smart Energy” application that allows integration of smart
meters into the ZigBee network together with other devices .
• By using this application, smart meters can collect information from the integrated
devices and control them. Moreover, the consumers can view their energy
consumption in real-time. It also allows better energy consumption and real-
time dynamic pricing.
• The advantages of ZigBee application in smart grid are low price, small size and it
uses relatively small bandwidth.
• The disadvantages of the ZigBee are small battery that limits its lifetime, small
memory, limited data rate and low processing capability. Moreover, its operation in
unlicensed frequency of 868 MHz and 2.4 GHz may have interference with other
Wi-Fi, Bluetooth and Microwave signals.
47

48. 48

49. 49

50. Types of Network Topologies of Smart Grid
Connections
• Local Area Network
• Home Access Network
• Neighborhood Area Network(NAN)
50

51. Local Area Network 1/5
• Each computer in the network access a common set of rules
(Ethernet/IEEE 802.3, Token Ring/IEEE 802.3 or 880.2 available
through IEEE PRESS)
• allows users to communicate to each other
• Each hardware device in LAN is a node
• The LAN can operate or integrate up to several hundreds of computer
• LAN combines high speed with geographical spread of 1-10 km
51

52. Local Area Network 2/5
• LAN may access other LANs or tap into wide area network
• LAN is a shared access technology, meaning that all the attached devices share a common
medium of communication
• A physical connection device, the network Interface Card(NIC), connects to the network
• The network software manages communication between stations on the system
• Most modern wireless local area networks (WLANs) are based on IEEE 802.11 standards,
marketed under the Wi-Fi brand name.
• WLAN could be easily integrated into smart grid due to its vast deployment around the
world. WLAN works in 2.4 GHZ - 3.5 GHz frequencies.
• The advantages of WLAN are low cost, vast deployment around the world, plug and play
devices.
• The major disadvantage of WLAN is high potential for interference with other devices
that communicate on the same frequencies.
52

53. Categories of Data Transmission in LAN 3/5
• Unicast Transmission: a single data packet is sent from a source node to a
destination (address) on the network
• Multicast Transmission: a single data packet is copied and sent to a specific
subset of nodes on the network; the source node addresses the packet by
using the multicast addresses
• Broadcast Transmission: a single data packet is copied and sent to all
nodes on the network; the source node addresses the packet by using the
broadcast address
53

54. LAN TOPOLOGY 4/5
• Bus Topology: linear LAN architecture in which
transmission from network station propagates the length of
the medium and is received by all other stations connected
to it
• Ring bus topology: a series of devices connected to one
another by unidirectional transmission links to form a single
closed loop
• Star Topology: the end points on a network are connected to
a common central hub or switch by dedicated links
• Tree Topology: identical to the bus topology except that
branches with multiple nodes are also possible
54

55. Special attributed and advantages of LAN 5/5
• Resource sharing:
• Area covered Cost and availability:
• High channel speed: ability to transfer data at rates between 1 to 10
million bits per second
• Flexibility: grow/expand with low probability of error; easy to maintain
and operate
55

56. Home Access Network
• LAN is confined to an individual home
• It enables remote control of automated digital devices and appliances
through out the house
• Smart meters, smart appliances and web-based monitoring can be integrated
into this level
56

57. Neighborhood Area Network (NAN)1/3
• Cover an area larger than a LAN
• It is a wireless community currently used for wireless local distribution applications
• Some architecture structures focus on the integration and interoperability of the
various domains within the smart grid
• Domains consists of devices and other subsystems which have similar
communication characteristics
• Gathers a huge volume of various types of data and distributes important control
signals from and to millions of devices installed at customer premises
• The most critical segment that connects utilities and customers in order to enable
primarily important SG applications
57

58. Characteristics of Nan 2/3
• To support a huge number of devices that distribute over large geographical
areas
• Must be scalable to network size and self-configurable
• Heterogeneous and location-aware
• Link condition and thus network connectivity are time-varying due to
multipath fading, surrounding environment, harsh weather, electricity power
outage, etc.
58

59. Characteristics of NAN 3/3
• Deployed outdoor, thus must be robust to node and link failures
• Carries different types of traffic that require a wide range of QoSs
• Needs QoS awareness and provisioning
• Mainly supports Multi-Point-to-Point (MP2P) and Point-to-Multiple-Point
(P2MP) traffic
• Very vulnerable to privacy and security
59

60. Various Domains
• Bulk Generation:
• Transmission
• Distribution
• Customer
• Service Providers
• Operations
• Market
60

61. Measurement Technology
• Smart grid environment requires the upgrade of tools for sensing, metering
and measurements at all levels of grid.
• These components will provide the data monitoring the grid and the power
market
• Sensing provides outage detection and response
• Provides energy theft protection
• Enables consumer choice
• Various grid monitoring functions
61

62. Types
• Wide Area Monitoring Systems
(WAMS)
• Phasor Measurement Units (PMU)
• Smart Meters
• Advanced Metering
Infrastructure(AMI)
• Remote Terminal Units (RTU)
62

63. Sensor’s Attributes to Smart Grid
• Outage detection and response
• Evaluates the health of equipments and the integrity of the grid
• Eliminates the meter estimations
• Provides the energy theft protection
• Enables consumer choice and DSM
63

64. 1: Wide area monitoring systems (WAMS)
• Wide area monitoring systems (WAMS) are essentially based on the new data
acquisition technology of phasor measurement and allow monitoring transmission system
conditions over large areas in view of detecting and further counteracting grid
instabilities.
• Current, voltage and frequency measurements are taken by Phasor Measurement Units
(PMUs) at selected locations in the power system and stored in a data concentrator every
100 milliseconds. The measured quantities include both magnitudes and phase angles, and
are time-synchronised via Global Positioning System (GPS) receivers with an accuracy of
one microsecond.
• A Wide Area Monitoring System (WAMS) based on Phasor Measurement Units
(PMUs) is being installed mainly to increase security of supply by capturing the dynamic
behavior of the system.
64

65. Continue…
• The phasors measured at the same instant provide snapshots of the status of
the monitored nodes. By comparing the snapshots with each other, not only
the steady state, but also the dynamic state of critical nodes in transmission
and sub-transmission networks can be observed. Thereby, a dynamic
monitoring of critical nodes in power systems is achieved.
• This early warning system contributes to increase system reliability by
avoiding the spreading of large area disturbances, and optimizing the use of
assets.
65

66. Continue…
• Demand Response (DR) technologies allow utilities to talk to devices
inside the customer premise. They include such things as load control
devices, smart thermostats and home energy consoles. They are essential to
allow customers to reduce or shift their power use during peak demand
periods.
• Demand response solutions play a key role in several areas: pricing,
emergency response, grid reliability, infrastructure planning and design,
operations, and deferral.
66

67. 67

68. 68

69. 69

70. 70

71. 71

72. 72

73. 73

74. 2: SCADA
• “Supervisory Control And Data Acquisition”
• Computer controlled system that monitors, controls and records industrial or utility
processes.
• Implications
• Supervisory Control → Big Picture
• set parameters for control
• monitor performance
• Program able Electronic Controllers
• Usually involves communication with remote site(s)
• Data is displayed and recorded on a PC
74

75. Internet
(ISP)
SCADA Station
Plant PLC and Remote I/O
Mobile Web Thin Clients
(Web-browser)
Monitor the Process
Manage Events and Alarms
75

76. 3: PMU….
• A device (mostly microprocessor based) which reports the magnitude and
phase angle of an analog and /or derived phasor with respect to the global
time reference, as per the synchro-phasor standards ( IEEE 1344, IEEE
C37.118).
76

77. PMU
77

78. 78

79. 79

80. 80

81. 4: Smart Meters
Smart meters have two functions:
1: providing data on energy usage to customers (end-users) to help control cost
and consumption: sending data to the utility for load factor control, peak-
load requirements.
2: The development of pricing strategies based on consumption information
and so on.
3: Automated data reading is an additional component of both smart meters
81

82. Smart Meter Attributes
Lets the customer to know:
1: How much energy they use
2: How much they pay.
3: When they use energy
Helps Utility in:
1: Better load pricing
2: Faster outage detection and restoration
3: Accurate billing
4: Enhanced grid monitoring
82

83. Advanced Metering Infrastructure (AMI)
• AMI is the convergence of the grid,
the communication infrastructure,
and the supporting information
infrastructure.
83

84. 84

85. 85

86. Functions of AMI
• Market applications:
1: Serve to reduce/eliminate labor, transportation, and
infrastructure costs associated with meter reading and
maintenance,
2: Increase accuracy of billing, and allow for time-based rates
while reducing bad debts; facilitates
3: Informed customer participation for energy management
• Customer applications:
1: serves to increase customer awareness about load reduction,
reduces bad debt, and improves cash flow, and enhances
customer convenience and satisfaction;
2: Provides demand response and load management to improve
system reliability and performance 86
• Distribution operations:
1: Curtails customer load for grid management,
2: Optimizes network based on data collected,
3: Allows for the location of outages and
restoration
of service,
4: Improves customer satisfaction, reduces energy
losses,
5: Improves performance in event of outage with
reduced outage duration and optimization of the
distribution system and distributed generation
management,
6: Provides emergency demand response

87. Phasor Data Concentrator
• A Software application runs on normal desktop PC- and collects data
from multiple PMUs
• Dedicated Server application designed to accept several PMU data and
analyze the data depending on application requirement
• Dedicated hardware/software to do real time monitoring and control studies
using PMU data
87

88. 88

89. Remote Terminal Units(RTU)
• A remote terminal unit (RTU) is a microprocessor-controlled electronic
device that interfaces objects in the physical world to a distributed control
system or SCADA (supervisory control and data acquisition) system by
transmitting telemetry data to a master system, and by using messages from
the master supervisory system to control connected objects. Another term
that may be used for RTU is remote telecontrol unit.
• An RTU is an electronic device that transmits real-time data to a
distributed control system.
89

90. Remote Terminal Units(RTU)
• RTUs in smart grids are used with SCADA for data collection.
• The RTUs are connected to field electrical equipment, such as
sensors, which send signals to the RTUs.
• The basic function of the RTU is to convert the sensor signals into digital
signals and then send the encoded digital data to the control center. At the
same time, they also communicate control commands to the field equipment.
90

91. Continue….
• In SCADA systems, an RTU is a device installed at a remote location
that collects data, codes the data into a format that is transmittable
and transmits the data back to a central station, or master.
• An RTU also collects information from the master device and
implements processes that are directed by the master. RTUs are
equipped with input channels for sensing or metering, output channels for
control, indication or alarms and a communications port.
91

92. Architecture of RTU
• An RTU monitors the field digital and analog parameters and transmits data to the Central
Monitoring Station. It contains setup software to connect data input streams to data output
streams, define communication protocols, and troubleshoot installation problems.
• An RTU may consist of one complex circuit card consisting of various sections needed to
do a custom fitted function or may consist of many circuit cards including CPU or
processing with communications interface(s), and one or more of the following: (AI)
analog input, (DI) digital input, (DO/CO) digital or control (relay) output, or (AO) analog
output card(s).
92

93. Applications of RTU
• Remote monitoring of functions and instrumentation for:
• Oil and gas (offshore platforms, onshore oil wells)
• Networks of pump stations (wastewater collection, or for water supply)
• Environmental Monitoring systems (pollution, air quality, emissions monitoring)
• Mine sites
• Air traffic equipment such as navigation aids (DVOR, DME, ILS and GP)
• Remote monitoring and control of functions and instrumentation for:
• Hydro-graphic (water supply, reservoirs, sewerage systems)
• Electrical power transmission networks and associated equipment
• Natural gas networks and associated equipment
• Outdoor warning sirens
93

94. 94

95. • A microprocessor based device that interfaces with instruments and
equipment at the facility and provides for control and communications.
• Often is connected to an OIT/HMI
• Communicates with master
• Programmable for local/distributed control
• Usually uses relay ladder logic
• And, or, not, Boolean Statements, math calculations, etc.
• If it can be put in words it can probably be put in RLL
• Interface with local facility inputs and outputs (I/O)
• Analog I/O & Discrete I/O
95
Programmable Logic Controller

96. 96

97. Popular communication technologies in Indian Power systems:
Technology %Usage
• Power Line Carrier 50
• Analog/digital Micro wave 15
• Fiber Optic 30
• GSM/GPRS <1
• V-sat 5
97

98. Challenges for Indian scenario
• Indian Power networks growing faster, larger & more complex.
• Data communication needs to be much faster catering to smart grid
initiatives being taken up.
• With faster, smarter & innovative technologies, data security to be
addressed adequately.
• All radio communication to be replaced with fibre optic network by
Dec.,2011 as per GOI decision.
98

99. 99

100. Future Trends and Challenges
• Interference: Developing algorithms that will eliminate/reduce the interference by using
active filters.
• Data Transmission Rate: Developing appropriate high data rate communication
technology or improving existing technologies such as WLAN or cellular networks. It
should be further increased by using new modulation techniques and improved
transmitters/receivers.
100

101. Continue…
• Standardization: Although there are many standards for smart grid communication, there
is no sufficient standard and model for integration of different communication technologies
in one system. Therefore, such standards should be developed.
• Cyber Security: The communication system becomes more vulnerable when it is not fully
dedicated to the smart grid communication and shared with other user, e.g. WLAN or
cellular network. In order to avoid this, the cyber protection has to be applied in both
physical and software level. At the physical level, the smart meters and LDCs have to be
physically secured to prevent unauthorized access. At the software level, new advanced
encryption algorithms has to be developed and applied.
101

102. Continue…
• Scalability: Accommodation of more and more devices like smart meters and bandwidth
adjustments according to additional users are need to be focussed.
• Self healing:
1. To avoid system breakdown
2. Must start self-healing actions within a small period of time after any contingency
3. Fast control signalling
• Interoperability: Need to improve the following
1. Ability of various systems or components to work with each other in a smooth
manner
2. Different domains of smart grid like generation, transmission, distribution,
customers, operations, markets and Independent System Operators are needed to be
interoperable and compatible from older to the newest versions 102

103. Continue…
• Complexity: Need to handle
1. Modelling, analysis and design of smart grid
2. Interdependence between different infrastructures
3. Distributed nature of monitoring and control functions
• Efficiency:
1. Optimization of network parameters
2. Accurate time measurements
3. Faster control messaging
4. Integrated communications devices
5. Enhanced computing
6. Appropriate network topologies
103

104. Conclusion
• The future smart grid is based on combination of legacy grid with advanced smart
metering, remote sensing, remote control of all key components and equipment.
• The success of the smart grid depends directly on reliable, robust and secure
communication system with high data rate capability.
• Future work should concentrate on development of improved security algorithms
that could be adapted for the smart grid communication and protocols and methods
for interference reduction and elimination.
104

105. References
• Ma, Ruofei, et al. "Smart grid communication: Its challenges and
opportunities." IEEE transactions on Smart Grid 4.1 (2013): 36-46.
• Kabalci, Yasin. "A survey on smart metering and smart grid
communication." Renewable and Sustainable Energy Reviews 57 (2016): 302-318.
• Yigit, Melike, et al. "Power line communication technologies for smart grid
applications: A review of advances and challenges." Computer Networks 70 (2014):
366-383.
• Gao, Jingcheng, et al. "A survey of communication/networking in smart
grids." Future generation computer systems 28.2 (2012): 391-404.
• Momoh, James A. Smart grid: fundamentals of design and analysis. Vol. 63. John Wiley &
Sons, 2012.
105

106. Questions?
1: Mention various communication technologies used at present in Smart Grid
systems?
2: Mention about various measurement techniques/devices integrated in modern
Smart Grid conditions?
3: Compare between various smart grid communication technologies?
4: Write short notes on:
• WAMS
• AMI
• ZigBee
• PLC
• PLCC
106