BEM Systems Architecture 4

1
Intelligent Buildings Technology

• BEM Systems Architecture 4

Decentralized architecture
Centralized architecture
2
Intelligent Buildings Technology

• BEM Systems Architecture 5

3
BEM Systems Communication 1
Intelligent Buildings Technology

• Communication protocols are necessary as
  communication interfaces between the elements
  that consist the systems (sensors, actuators,
  controllers, etc.)
• Information should be transferred and delivered
  in a certain way that is defined by the
  communication protocol
• The compatibility of each element of the BEM
  system with the communication protocol is an
  essential parameter when structuring the system

4
BEM Systems Communication 2
Intelligent Buildings Technology

• Network topologies determine the way the Operator
  Workstation (OWS) is connected with the various
  equipment
• Point-to-Point The simplest approach where the
  OWS is directly connected with an outstation
• Star Like Point-to-Point but more than one units
  are connected to OWS
• Bus The various units communicate independently
  between them and the OWS. The extension of the
  network is simple
• Ring Information is transferred around the ring
  only in one direction. Each unit recognizes if
  the information is of its own concern, otherwise
  information bypasses the unit (token-passing
  protocol)
• Tree or Hierarchical Units communicate through a
  tree topology

5
BEM Systems Communication 3
Intelligent Buildings Technology
6
BEM Systems Communication 4
Intelligent Buildings Technology
7
BEM Systems Communication 5
Intelligent Buildings Technology
8
BEM Systems Communication 6
Intelligent Buildings Technology
9
BEM Systems Communication 7
Intelligent Buildings Technology
10
BEM Systems Sensors
Intelligent Buildings Technology

• Measurement of solar radiation
• Temperature sensors
• Humidity sensors
• Measurement of wind velocity and direction
• Flow metering sensors
• Air pollutants measurement sensors (CO, CO2)
• Presence/Occupancy sensors

11
BEM Systems Sensors
Intelligent Buildings Technology
12
BEM Systems Sensors
Intelligent Buildings Technology
13
BEM Systems Sensors
Intelligent Buildings Technology
14
BEM Systems Sensors
Intelligent Buildings Technology
15
BEM Systems Sensors
Intelligent Buildings Technology
16
BEM Systems Sensors
Intelligent Buildings Technology
17
BEM Systems Sensors
Intelligent Buildings Technology
18
BEM Systems Sensors
Intelligent Buildings Technology
19
BEM Systems Actuators
Intelligent Buildings Technology

• The selection of an actuator should be based on 2
  main criteria
• Control strategy
• The type of equipment that will be controlled
• Reliability the power of the actuator should
  respond to real operational conditions (e.g. wind
  pressure on shading devices)
• Time respond Should be small especially in
  security systems control or error handling
• In case of malfunction same control equipment
  should be return to a security position
• Other criteria accuracy, compatibility with the
  network, life time, maintenance, calibration, etc.

20
BEM Systems Actuators
Intelligent Buildings Technology
21
BEM Systems Actuators
Intelligent Buildings Technology
22
BEM Systems Actuators
Intelligent Buildings Technology
23
BEM Systems Actuators Shading devices
Intelligent Buildings Technology
24
BEM Systems Actuators Shading devices
Intelligent Buildings Technology
25
BEM Systems Actuators Ventilation
Intelligent Buildings Technology
26
BEM Systems Actuators Ventilation
Intelligent Buildings Technology
27
BEMS Control of the System
Intelligent Buildings Technology

• Open loop
• Closed loop

28
BEMS Control of the System
Intelligent Buildings Technology

• On/Off There are only 2 states of outputs (e.g.
  in a valve fully opened/fully closed)

29
BEMS Control of the System
Intelligent Buildings Technology

• Logic programming The implementation of the
  control strategy is based on the use of logical
  rules
• IF (Room temperature is over 26C) THEN (Close
  blinds) AND (Switch fans off)
• The connected appliances are controlled mainly by
  On/Off

30
BEMS Control of the System
Intelligent Buildings Technology

• Fuzzy Logic This kind of control require the
  synthesis of a large number of parameters and
  sometimes is quite difficult to predict the
  behavior of the controller
• The use of fuzzy logic can be efficient for
  controlling complicated parameters such as
  thermal comfort

31
BEMS Control of the System
Intelligent Buildings Technology

• Neural Networks The structure of these
  controllers tries in a certain way to emulate the
  function of the human brain
• They are using mainly in non-linear systems
• The can divided in various layers. The 1st layer
  is composed by the Inputs while the last by the
  Outputs
• A layer may includes nodes that connect this
  layer with nodes in the next layer through
  weighted links

32
BEMS Control of the System
Intelligent Buildings Technology
33
BEMS Control of the System
Intelligent Buildings Technology
34
Intelligent Buildings Technology

• Communication
• Protocols

35
Intelligent Buildings Technology

• Communication protocols
• Industrial progress in semiconductor development
  and growing demands by the end user, e.g. better
  control performance, have led towards advanced
  control systems, known as serial networked
  control network systems. Features of these
  control systems are
• Distributed intelligence, using microcontrollers.
  
• Real-time operations are possible.
• Peer-to-peer architecture.
• Memory and software programs are provided at node
  level.
• Software is implemented in layered protocol
  stacks.
• The limitations of serial networked control
  systems lie mainly in network expansion, a
  limited variety of topologies and transmission
  media. These limitations are overcome by the new
  generation of distributed control network systems
  with the following features
• Mixing of communications media (twisted pair,
  power line, radio, infrared, fibre optics,
  coaxial).
• A better, or more complete, implementation of the
  OSI model with higher reliability of the
  (growing) network.
• Free topology.
• User-friendly software and available development
  tools.
• Connectivity units, gateways, bridges, routers
  and repeaters.

36
Intelligent Buildings Technology

• Communication protocols
• With distributed control network systems a major
  step towards intelligent building automation
  systems has been made, resulting in
• Lower operating costs
• Demands for sharing information
• Improved human environment, especially work place
  conditions
• Improved building performance and economy
• Similar to a factory plant, a public building
  includes several types of network systems, such
  as
• Building automation systems responding to
  external conditions and controlling the internal
  environment or generating alarms.
• Building management systems monitoring, managing
  and storing control data.
• Local area network system handling information
  exchange within a company.
• Communication systems providing links for
  worldwide communication and data exchange.

37
Intelligent Buildings Technology

• Communication protocols
• Building automation systems are used for the
  following automation services and control tasks
• Heating Ventilation Air Conditioning (HVAC)
• Lighting and emergency lighting control
• Power management
• Security and protection
• Transport (lifts)
• These automation services are currently supported
  by communication protocols such as
• BACNET
• ARCNET
• BitBus
• CAN
• EIBUS
• LonWorks
• PROFIBUS
• And many other systems based on RS-232, RS-422,
  or RS-485 communication standards.

38
Intelligent Buildings Technology

• Communication protocols EIBUS
• Founded in 1990 by 15 firms, the European
  Installation Bus (EIB) Association is now an
  association of almost 100 electrical installation
  firms who have joined together for the purpose of
  bringing about a common standard for installation
  buses in the market place. Their objective for a
  uniform building management system throughout
  Europe is achieved by
• Laying down technical directives for systems and
  products.
• Devising quality rules.
• Drawing up test procedures.
• Making system know-how available to members,
  subsidiaries and licensees.
• Engaging test institutes to perform quality
  inspections.
• Granting third parties who pass tests the use of
  the "EIB" mark.
• Taking an active part in standardization.

39
Intelligent Buildings Technology

• Communication protocols EIBUS
• EIB concentrates unequivocally on home and/or
  building management. This focus permits it to
  deal with all tasks and challenges within this
  domain thoroughly and efficiently. The European
  Installation Bus (EIB) is an open, comprehensive
  system that covers all aspects of Building
  Automation.
• Though standardized Bus Access Unit (BAU)
  building blocks are available from several
  vendors. This means EIB is open EIB may be
  implemented by anyone, on any chip or processor
  platform chosen - both as proprietary
  implementation for individual products, as well
  as for OEM BAU's. Conformity tests are defined,
  and EIB Certification is open to all members of
  the Association.
• Why "in 0th approximation"? Because EIB embeds
  the protocol in an encompassing Home and Building
  Electronics System, with standardized system
  components (such as the BAUs), network management
  and interworking standards, with a vendor-neutral
  tools and programming interfaces for PC's,
  training for electrical contractors,
  certifications schemes etc.

40
Intelligent Buildings Technology

• Communication protocols EIBUS
• The European Installation Bus (hereafter referred
  to as "the Installation Bus" or in short as "the
  Bus") is designed as a management system in the
  field of electrical installation for load
  switching, environmental control and security,
  for different types of buildings. The
  Installation Bus can be installed in large
  buildings such as business premises, schools,
  hospitals, factories and administration premises
  as well as in domestic residences. Its purpose is
  to ensure the monitoring and control of functions
  and processes such as lighting, window blinds,
  heating, ventilation, air-conditioning, load
  management, signaling, monitoring and alarms.
• The EIB system allows the bus devices to draw
  their power supply from the communication medium,
  like Twisted Pair or Powerline (230 V mains).
  Other devices may, additionally, require power
  supply from the mains or other sources, as in the
  Radio Frequency and Infrared media. Fig. 3.4
  draws some usage examples.