ISO/IEC 30144:2020

ISO/IEC 30144
Edition 1.0 2020-10
INTERNATIONAL
STANDARD
colour
inside
Internet of things (IOT) – Wireless sensor network system supporting electrical
power substation
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ISO/IEC 30144
Edition 1.0 2020-10
INTERNATIONAL
STANDARD
colour
inside
Internet of things (IOT) – Wireless sensor network system supporting electrical

power substation
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.10; 35.110 ISBN 978-2-8322-8941-9

– 2 – ISO/IEC 30144:2020  ISO/IEC 2020
CONTENTS
FOREWORD . 4
INTRODUCTION . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Symbols and abbreviated terms . 9
5 Intelligent wireless sensor network system supporting electrical power substation . 10
5.1 System View . 10
5.1.1 System overview . 10
5.1.2 Subsystems and their relationships. 13
5.2 Communications View . 15
5.2.1 Communications overview . 15
5.2.2 Sensor nodes . 16
5.2.3 Gateways . 17
5.2.4 Communication interfaces in the iWSN system . 18
6 Technical requirements for the iWSN system supporting electrical power
substations . 19
6.1 System functional requirements . 19
6.1.1 Information acquisition and collection . 19
6.1.2 Device management . 19
6.1.3 Data analysis . 19
6.1.4 Data display . 19
6.1.5 Warning and response . 20
6.1.6 Network communication . 20
6.1.7 System privilege management . 20
6.1.8 Collaborative information process (CIP) and decision support. 20
6.2 System performance requirements . 20
6.2.1 Performance requirements of sensor node. 20
6.2.2 Performance requirements of gateway . 23
6.2.3 Performance requirements of control subsystem for sensor network . 25
Annex A (informative) Sensor network reference architecture from ISO/IEC 29182-3 . 27
A.1 Overview of sensor network interfaces . 27
A.2 Sensor node physical reference architecture . 29
A.3 Functional model of the sensor network . 30
Annex B (informative) The sensor models in IEC 61850 . 31
Bibliography . 35

Figure 1 – System overview of the iWSN system supporting electrical power substation . 11
Figure 2 – Communications overview of the iWSN system supporting electrical power
substation . 16
Figure A.1 – Overview of sensor network interfaces in a sensor node, sensor node
to sensor node, and sensor node to the external environment . 27
Figure A.2 – Sensor networks system architecture – Layer focused . 28
Figure A.3 – Sensor node physical reference architecture . 29
Figure A.4 – Functional model of the sensor network . 30

Table 1 – Mapping between the entities in the System View and the domains
of the IoT RA . 12
Table 2 – Interface for functional subsystem of sensor networks . 18
Table B.1 – Sensor models in IEC 61850 . 31

– 4 – ISO/IEC 30144:2020  ISO/IEC 2020
INTERNET OF THINGS (IOT) –
WIRELESS SENSOR NETWORK SYSTEM
SUPPORTING ELECTRICAL POWER SUBSTATION

FOREWORD
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International Standard ISO/IEC 30144 has been prepared by subcommittee 41: Internet of
Things and related technologies, of ISO/IEC joint technical committee 1: Information technology.
The text of this International Standard is based on the following documents:
FDIS Report on voting
JTC1-SC41/163/FDIS JTC1-SC41/176/RVD

Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
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INTRODUCTION
The data collected from various types of electrical equipment is sparsely located, and on-line
transmission of the data helps to collaboratively aggregate and analyse them in real-time.
Transitioning to the smart electrical power substation using wireless communication among the
sensor nodes – i.e. wireless sensor network (WSN) – requires systems architecture provisioning
automated data collection from the electrical equipment, which allows collaborative data
processing, sends automatic alerts, provides preventive actions, and potentially takes
corrective actions for certain situations.
Electrical power substation communications should be designed to support scalability,
interoperability, autonomous fault correction, and other key attributes. The intelligent wireless
sensor network (iWSN) is inherently flexible and scalable in its capabilities and in operations
including in the size of its converge areas; however, depending on the geographical (e.g. urban,
suburban, remote location) and structural (both natural and man-made) situations, the
installation architecture should ensure the fidelity of all sensor nodes’ wireless connectivity.
Furthermore, the WSNs can support either distributed or decentralized network architecture.
The wired substation network typically uses high-availability seamless ring (HSR) and parallel
redundancy protocol (PRP) protocols (see IEC 62439-3, IEC 61850-8-1 and IEC 61850-9-2) to
provide seamless failover against failure of any network component. For the iWSN, it is also
important to have the key iWSN network components (e.g. sensor nodes) from data
communication failure. Therefore it is important to select wireless sensor network architecture
for a substation which overcomes the potential issue of a single point of failure in the wireless
sensor network, for example, by installation architecture, the use of PRP to improve packet loss
and timing behaviour in wireless network, or a combination of these.
This document introduces iWSN as a system which helps to make the power substation smarter,
which is compatible with IEC 61850. In the past, wireless communication was thought to be
unreliable and ineffective over long distances. With the advancements in communication
technologies in the last decade, the wireless communications have given rise not only to
wireless meshed systems, multi-hop and self-healing networks, but also to various low-power
protocols having high network/communication security standards. Additionally, different
network topologies with effective wireless signal routing algorithms have improved range and
reduced power consumption while minimizing frequency of communication channel error. These
improvements can be leveraged to form a highly reliable communication network for the
electrical power substation.
The existing applications of the WSNs in smart grid include, but are not limited to, automatic
meter reading, remote system monitoring and control, equipment fault diagnostics, distribution
automation, outage detection, line fault and electronic fault detection, underground cable
system monitoring, towers and poles monitoring, conductor temperature and dynamic thermal
rating. However, the realization of these existing and envisioned WSN-based smart grid
applications is hindered by not having uniform sensing data formats, data interfaces, etc.
Although some sensor communication systems are not compatible with the devices from
different equipment manufacturers, most intelligent electronic devices used in electrical power
substations are interoperable, through the use of standard protocols, for example, IEC 61850
GOOSE, TCP, UDP, etc., and standards related to the common information model (CIM) defined
by IEC 61970 and IEC 61968. For cases where new types of sensors (either existing or newly
developed) have not adopted IEC 61850, they may be used with an intelligent wireless sensor
1 2
network (iWSN) system   because the iWSN system interfaces can act as an adaptor for the
sensors and the rest of the systems.
_____________
Wireless technology in general is not suitable for the transmission of mission critical data such as sampled
measured values according to IEC 61850-9-2 or trip signals for circuit breakers due to the possible interference
of electromagnetic radiation caused by arc-flashes (e.g. in case of an internal fault or switching operations inside
a substation) with the radio signals of wireless sensors.
Any data commonly sent over layer 2 broadcast (e.g. GOOSE) are not suitable for transmission over wireless
networks due to the unavailability of corresponding broadcast features.

– 6 – ISO/IEC 30144:2020  ISO/IEC 2020
The main purpose of wireless sensor network applications for electrical power substations is to
improve the capability of acquiring, monitoring, processing, and maintaining the data and
information from the power equipment. A wireless sensor network (WSN) is characterized by
flexible deployment, device collaboration and low-cost implementation, and WSN realizes
efficient monitoring of the smart grid systems and subsystems. By enabling the monitoring and
controlling capabilities by installing wireless sensor nodes on critical power grid equipment,
reliable and real-time online management of this equipment can be accomplished.
Electrical power substation is one of the most important building blocks of the smart grid. The
monitoring and control systems in electrical power substations acquire current, voltage, status
and other parameters from their primary equipment, and also data from their environment. The
information from the measurement systems provides the basis for integrated applications,
enabling the transformation of a conventional electrical power substation to a smart electrical
power substation, especially when considering the use of the IEC 61850 series, iWSN and other
information technologies. In addition to the substation equipment’s (wired) connectivity, which
is likely based on the IEC 61850 series, the iWSN system will provide additional benefits to
collect, process, and transmit data/information about power substation equipment and its
environment. An effective and efficient sensing system can be achieved by an iWSN system
which takes the role of a data/information measurement and collection system. The concept of
the iWSN system provides functions, such as automatic data collection and aggregation,
collaborative information processing (e.g. data/information fusion), data analysis, and alarming,
and other functional applications that enable the intelligence or smartness of the system that
the iWSN system is monitoring.
The information collected in an electrical power substation about the equipment state and the
flow of electricity provides the electricity providers with a clearer view and better control over
the electrical power substation. Among the many add-values that the iWSN brings compared to
the wired installation, one of them is the migration to the no-wire installation as all the sensor
nodes are powered by batteries and the data is transmitted via the wireless communication
links of the iWSN. A wireless sensor network, that is able to communicate with the utility
provider’s control system by sharing the collected information with the existing networks
becomes an attractive technology to deploy in an electrical power substation in order to collect
required and critical information.
This document is built upon ISO/IEC 29182 (Sensor Network Reference Architecture) and
ISO/IEC 30101 (sensor network and its interfaces for smart grid systems), IEC 61850
(communication networks and systems for power utility automation), and ETSI’s and NIST’s
work in smart grid, and extends ISO/IEC 29182 and ISO/IEC 30101 to the application standard
of the sensor network that supports the electrical power substations.
The iWSN system uses wireless sensor networks for power substations including substation,
equipment, facility, environment, etc. The existing communication protocols specified in
IEC 61850-8-1 and IEC 61850-9-2 can be used within power substation, or IEC 61850-8-2 can
be used over public network. This document provides the iWSN system’s infrastructure from
System and Communications Views and also specifies the iWSN system’s technical
requirements to realize and support the smart electrical power substation. Electrical power
substations with sensor networks use advanced information and communication technologies
in order to improve the efficiency, reliability, and security of their components and services.

INTERNET OF THINGS (IOT) –
WIRELESS SENSOR NETWORK SYSTEM
SUPPORTING ELECTRICAL POWER SUBSTATION

1 Scope
This document specifies
– intelligent wireless sensor network (iWSN) from the perspectives of iWSN's system
infrastructure and communications internal and external to the infrastructure, and
– technical requirements for iWSN to realize smart electrical power substations.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61000-4-39, Electromagnetic compatibility (EMC) – Part 4-39: Testing and measurement
techniques – Radiated fields in close proximity – Immunity test
IEC 61326-1, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 1: General requirements
IEC 61850-3, Communication networks and systems for power utility automation – Part 3:
General requirements
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
control subsystem for sensor network
CSSN
platform together with all the sensor nodes communicated to it with networks, including the
rules for control, for communication and for management among application processes of
sensor network
[SOURCE: IEC 60050-732:2014, 732-10-02, modified – In the definition, "home network",
"devices" and "attached to it" have been replaced by "platform", "sensor nodes" and
"communicated to it with networks", respectively, and "of sensor network" has been added at
the end.]
– 8 – ISO/IEC 30144:2020  ISO/IEC 2020
3.2
control subsystem for power substation
CSPS
infrastructure together with all the equipment attached to it, including the rules for control, for
communication and for management among application processes of a power substation
[SOURCE: IEC 60050-732:2014, 732-10-02, modified – In the definition, "home network" and
"devices" have been replaced by "infrastructure" and "equipment", respectively, and "of a
power substation" has been added at the end.]
3.3
data acquisition functional subsystem
DAFS
subsystem for gathering required data from a group of sensors, and assembling them into
messages for delivery to another component
[SOURCE: IEC 60050-721:1991, 721-18-64, modified – In the definition, "a facility", "small
quantities of" and "a nominated group of addresses" have been replaced by "subsystem",
"required" and "a group of sensors", respectively, and "a single message" and "nominated
address" have been changed to "messages" and "component", respectively.]
3.4
intelligent wireless sensor network
iWSN
system of spatially distributed sensor nodes interacting with each other using wireless
communication technology and, depending on applications, possibly with other infrastructure in
order to acquire, process, transfer, and provide information extracted from its environment with
a primary function of information gathering, analysing, fusing, and possible control capability to
support the intelligent services based on the application scenarios and users
[SOURCE: ISO/IEC 29182-2:2013, 2.1.6, modified – In the definition, "using wireless
communication technology" and "analysing, fusing," have been added, and "to support the
intelligent services based on the application scenarios and users" has been added at the
end.]
3.5
sensor network for electrical power substation
system of spatially distributed sensor nodes interacting with each other and, depending on
electrical power substation applications, possibly with other infrastructure in order to acquire,
process, transfer, and provide information extracted from electrical power substation’s
equipment and environment with a primary function of information gathering and possible
control capability
[SOURCE: ISO/IEC 29182-2:2013, 2.1.6, modified – In the definition, "electrical power
substation" has been added in front of applications, and "its environment" has been replaced
by "electrical power substation’s equipment and environment".]
3.6
smart electrical power substation
part of an electrical system, confined to a given area, mainly including ends of transmission or
distribution lines, electrical switchgear and control gear, buildings and transformers, and
generally including safety or control devices (for example protection), with the infrastructures
and technologies of digital information, network communication and shared information to
collect data, measure, detect and protect the electrical system, possibly support online analysis,
decision-making, collaborative interaction, and real-time control

[SOURCE: IEC 60050-601:1985, 601-03-02, modified – "a" has been removed from the
beginning, and "A. substation generally includes" is replaced by "and generally including".
"network communication and shared information to collect data, measure, detect and protect
the electrical system, possibly support online analysis, decision-making, collaborative
interaction, and real-time control" is added in the end of the definition.]
3.7
reliability
ability to perform as required, without failure, for a given time interval, under given conditions
[SOURCE: IEC 60050-192:2015, 192-01-24]
3.8
availability
property of being accessible and usable on demand by an authorized entity
Note 1 to entry: IoT systems can include both human users and service components as "authorized entities".
[SOURCE: ISO/IEC 27000:2018, 3.7]
4 Symbols and abbreviated terms
ASD Application and Service Domain
CAN controller area network
CIP collaborative information process
CSPS control subsystem for power substation
CSSN control subsystem for sensor network
CT current transformer
DAFS data acquisition functional subsystem
DER distributed energy resource
EMF electromagnetic field
GIS gas isolated switchgear
GOOSE generic object oriented substation event
HMI human–machine interface
IED intelligent electronic device
iWSN intelligent wireless sensor network
LoRaWAN™ long range wide area network
OLTC on load tap changer
MMS manufacture message service
MTBF mean time between failures
MTTF mean operating time to failure
MTTFF mean operating time to first failure
NB-IoT narrow band Internet of Things
ONVIF open network video interface forum
OTA over the air
PD partial discharge
PED Physical Entity Domain
– 10 – ISO/IEC 30144:2020  ISO/IEC 2020
PSIA Physical Security Interoperability Alliance
RTU remote terminal unit
SCADA supervisory control and data acquisition
SCD Sensing and Controlling Domain
SF sulfur hexafluoride
SNRA Sensor Network Reference Architecture
SV sample value
UD User Domain
VT voltage transformer
XML extensible markup language
5 Intelligent wireless sensor network system supporting electrical power
substation
5.1 System View
5.1.1 System overview
The iWSN system for electrical power substation is composed of subsystems which include
sensor nodes, meters, cameras, and gateways, communication network, and control subsystem
for sensor network (CSSN). The iWSN system collects data (system operation status, etc.) from
electrical equipment and substation environment, and transmits the data wirelessly to be
processed, aggregated and/or analysed for effective and efficient monitoring of the electrical
power substation in real-time. The iWSN system contributes to the automation of the operation
and management of the substation especially by feeding it with appropriate data, but also
provides the electricity providers with a clearer operating picture of the substation and better
automated control through supervisory control and data acquisition (SCADA). In addition, with
consideration for sensor and actuator interoperable communication interfaces and common
sensor and actuator data for sharing and exchanges between networks and systems,
interoperability in electrical power substation operations should be achieved. Consequently, the
application of the iWSN system results in a smart electrical power substation through interactive
operations, self-healing, safer and securer environment, and so on. The system overview of the
iWSN system supporting electrical power substation is depicted in Figure 1. In Figure 1, SCADA,
control centre and control subsystem for power substation (CSPS) are only shown to provide
the relationship with iWSN, but SCADA, control centre and CSPS are neither in the scope nor
discussed in this document.
Figure 1 – System overview of the iWSN system
supporting electrical power substation
As shown in Figure 1, in principle, the iWSN system’s System View supporting electrical power
substation follows the Sensor Network Reference Architecture (SNRA) described in
ISO/IEC 29182. Figure 1 resulted from applying and tailoring the SNRA (see Figure A.1)
supporting electrical power substation monitoring. Figure 1 shows the entire sensor network
system that is used to improve the substation’s intelligence and automated system performance.
Sensor nodes (see Figure A.3) in Figure 1 are attached to power equipment or placed in the
substation to monitor the equipment and environmental status. The sensor nodes with different
type of sensors and communication modules are used for electrical power substations, and they
are listed in this document. The entire functional models of the iWSN system comply with those
of the SNRA (see Figure A.4). Interfaces of SNRA, layer focus model, sensor node physical
reference architecture and functional models of the sensor network are shown in Annex A.
The iWSN systems are used for monitoring the electrical equipment, environment, access
management, and other parameters in electrical power substations, and also provide numerous
other services depending on the needs of specific users. An iWSN system consists of sensor
nodes, gateways, and various types of the iWSN system’s subsystems. It also includes a
platform for managing the iWSN system that has a graphical user interface.
Since the iWSN system supporting electrical power substations is one of the application
scenarios of Internet of Things, it also follows the Internet of Things Reference Architecture
(IoT RA, ISO/IEC 30141). The mapping relationship between the entities in the iWSN system’s
System View (see Figure 1) and the domains of the IoT RA is shown in Table 1.

– 12 – ISO/IEC 30144:2020  ISO/IEC 2020
In Table 1, the four domains of the IoT Reference Architecture (see ISO/IEC 30141) are mapped
and included in the iWSN system supporting electrical power substation. They are Physical
Entity Domain (PED), Sensing and Controlling Domain (SCD), Application and Service Domain
(ASD), and User Domain (UD). The main conception and functions for the domains are as
follows.
Physical Entity Domain (PED): The PED mainly consists of sensed physical objects and
controlled physical objects, which are related to IoT applications and are of interest to users. A
sensed physical object is a physical entity from which information is acquired by sensors, while
a controlled physical object is a physical entity which is subject to actions of actuators. electrical
equipment, and the environment of the power substation are in the PED.
Sensing and Controlling Domain (SCD): In the SCD, the entities consist primarily of sensors,
actuators, and IoT gateways. Sensors sense properties of physical entities while actuators
change properties of physical entities. Sensors acquire information about a property of a
physical entity (e.g. physical, chemical, biological properties). Actuators change properties of
entities. Both sensors and actuators interact with physical entities independently or
collaboratively. IoT gateways are devices which connect SCD with other domains. IoT gateways
provide functions such as protocol conversion, address mapping, data processing, information
fusion, certification, and equipment management. IoT gateways should be either independent
equipment or integrated with other sensing and controlling devices. The IoT gateway should
also perform security functions for constrained IoT devices using the gateway for connectivity
to networks. The SCD might also contain local control systems which are used to run control
services, i.e. components for local management of IoT gateway capabilities in scenarios where
the IoT gateway is expected to work with or without upstream connectivity. DAFS is included in
the SCD.
Application and Service Domain (ASD): The purpose of the ASD subsystem is to host the core
functions, services and applications that deliver the IoT system functionality to the users
(human and/or digital). The ASD subsystem will provide mainly basic services, including
computing services such as data access, data processing, data fusion, data storage, identity
resolution, geographic information service and user management, and inventory management.
The ASD subsystem will also host business services and applications built on the generic
services, as the ability to host applications will be one of the services provided by the IoT
systems. CSSN is included in the ASD.
User Domain (UD): The UD contains both human users and digital users. Digital users are
devices of some type and they interact directly with other entities in the IoT system via network
interfaces or application programming interfaces. Human users interact using a user device
which contains some form of human–machine interface (HMI). A HMI subsystem contains the
devices and supporting software that allow human users to interact with the IoT system.
Depending on user role, different aspects of the system will be presented for observation and/or
control. Human users such as managers or operators of a power substation are included in the
UD.
Table 1 – Mapping between the entities in the System View
and the domains of the IoT RA
System View of the iWSN system supporting Internet of Things Reference Architecture
electrical power substation
DAFS Sensing and Controlling Domain (SCD)
CSSN Application and Service Domain (ASD)
Electrical equipment, and environment of the power
Physical Entity Domain (PED)
substation
Managers or operators of power substation User Domain (UD)

5.1.2 Subsystems and their relationships
In Figure 1, the substation control platform (SCP) contains two subsystems: (1) control
subsystem for sensor network (CSSN); and (2) control subsystem for power substation (CSPS).
These subsystems should be interconnected with the data acquisition functional subsystem
(DAFS) which contains the sensor nodes, controller(s) and gateways deployed for the electrical
power substations.
The existing substation system typically consists of the electrical equipment, intelligent
electronic devices (IEDs), and CSPS of the substation control platform. The electrical
equipment in the power substation mainly includes primary electrical equipment, current
transformer / voltage transformer (CT/VT) and control loops, and other sensors such as (but
not limited to) insulation, displacement, temperature, pressure, and humidity. IEDs include
relays, remote terminal units (RTUs), measuring and control devices, metering equipment, fault
recorders, engineer working stations and communication gateways, and these devices are
connected by cable networks or fibre-optic networks in substations. A typical IEC 61850 based
substation automation system architecture consists at least of a station bus and may use
process bus to communicate with intelligent process equipment. Communication services like
MMS (Manufacturing Message Specification), GOOSE (Generic Object Oriented Substation
Event) or SV (Sampled Values) are applied onto the station bus and/or process bus in
accordance with project requirements. The CSPS of the substation control platform is able to
control, protect and monitor electrical equipment inside the substation and the connected
electrical grid. Information security in substations is provided according project specific
implementation plans following security assessments e.g. by implementing firewalls, white-
listening, intrusion detection systems, etc.
The associated and connection relationship between the iWSN and the existing substation
system is shown in Figure 1. With regard to the local communication connectivity between DAFS
and the sensor information in the substation, as shown in Figure 1, the sensor information
should be shared at the local level within the SCD or through the CSSN within ASD. However,
the existing substation systems are neither within scope nor defined or discussed in this
document. The iWSN system should provide the measurement information of inherent and
additional measurements, but the strength of the iWSN system is in its flexibility in sensor node
deployment in a substation and in sensing diversity, enabling to measure various kinds of
parameters from equipment as well as from the substation’s environment, for example
temperature of the equipment or of one of its parts, SF leakage, partial discharge, humidity,
temperature, wind, water immersion, and fire. The measured parameters need to be associated
to analytics either on a physical element (e.g. sensor node or sensing device), on the DAFS
(e.g. gateway), on the CSSN, or on the CSPS (e.g. platform, cloud).
The iWSN system is composed of the DAFS and the CSSN, as shown in Figure 1. The DAFS
includes, but is not limited to, the following examples of management subsystems.
a) Equipment management subsystem: This subsystem collects the parameters of the
equipment such as transformer temperature, insulation gas (e.g. SF ), partial discharge,
solid insulation, temperature of the switch cabinet, other assisted parameter, etc.
For example:
1) Temperature profile of main transformer: Infrared thermal imager is used to monitor the
overall temperature distribution of the main transformer. The temperature profile of the
main transformer is analysed intelligently and alarmed if it is out of the normal ranges.
2) Insulation gas (e.g. SF ) online monitoring and control in gas isolated switchgear (GIS):
For example, a double infrared gas sensor is used to detect the insulation gas leakage.
If the leakage is detected, the alarm signal is sent to initiate the automatic exhaust
ventilation.
– 14 – ISO/IEC 30144:2020  ISO/IEC 2020
3) Equipment temperature monitoring: The wireless sensor node for measuring
temperature is used to monitor the operating temperature of some part of the high-
voltage electrical equipment such as the joint, sleeve and capacitor cell, and transmit
the data through wireless communication technologies to perform data report and
analysis. By fusing and comparing the temperature differences between different phases
of the same equipment, comparing the differences among the similar equipment, and
also comparing with the temperature of the environment, flexible equipment operation
temperature management is realized, and the accurate alarm for the equipment fault is
achieved.
4) Noise and vibration condition management: The wireless sensor nodes for noise and
vibration condition management and measurement are added to manage and measure
the condition of the devices for equipment management subsystem.
b) Environment management subsystem: This subsystem collects the data of temperature,
wind, lighting, water immersion, fire and other information in the environment. The potential
iWSN system application model examples are defined in condition monitoring (see
IEC 61850-7-4 and IEC TR 61850-90-3) and in environment monitoring
(see IEC TR 61850-90-6), etc.
NOTE Additional information on sensor models already in IEC 61850 is given in Annex B.
For example:
1) Fire monitoring and alarm: Data from video surveillance cameras, infrared thermal image
detector and smoke alarm is collected and aggregated to achieve the fire monitoring and
alarming with high reliability.
2) Water immersion alarm and drainage control: The wireless sensor node for water
immersion is deployed in the plant and on the cable to detect the water leakage and
water immersion, and transmit the data through wireless communication technologies to
perform data report and analysis, so as to realize on-line monitoring and automatic
drainage control for substation.
3) Other environment parameter monitoring: Wireless sensor nodes for temperature,
humidity and other environment parameters are used to monitor the environment of key
areas in the substation, such as the indoor and terminal box, and transmit the data
through wireless communication technologies to perform a comprehensive analysis,
judgment and alarm. Sensor nodes for ozone measurement should be added to detect
the ozone in the room for environment management subsystem. Furthermore, the
environmental information is aggregated with information of flooding and video
surveillance to achieve highly credible alarm for the status in the substation.
c) Access management subsystem: This subsystem detects the intrusion of the enclosure,
door and windows in the building, other abnormal entrance, etc. For example, Intrusion
monitoring: Infrared device, cameras, and other types of sensor nodes are used to collect
information of electronic fence, infrared radiation, wall vibration and video surveillance. All
of the information is aggregated and analysed to prevent outside intrusion and alarmed if
the intrusion is detected.
The management subsystems described above contain different sensors, sensor nodes,
communication protocols, and gateways based on the separate functions. The sensor and
sensor nodes are deployed on or in the electrical equipment, and closely associated with that
equipment depending on the acquisition information and characteristics. Sensor nodes and
gateways, which are the physical entities for the functional subsystems, are described in 5.2.
The CSSN is connected with the CSPS and integrated in the substation control platform (SCP).
The CSSN shall realize the following functions:
– collect the data from individual DAFS;

– perform data processing, analysis and f
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