Wireless M-Bus protocolfor Advanced Metering Infrastructure

SABER FERJANI

Who I am?• Education:

– 2010-2013: ENSI (Computer Science Engineering)– 2008-2010: IPEIEM (Scientific Preparatory)

• Experience:– 2013: Graduation project around Qemu translation cache policy– 2012: Hygrometer & Altimeter based on STM32, Line following

robot, Stepper motor control through Smartphone via Bluetooth.– 2011: PCB Multilayer Design Layout using Altium– 2010: Led Display spinning wheel– 2009: Thermometer based on PIC with serial interface

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http://about.me/ferjani

Framing• The European Conference for Renewable Energy in

Berlin in 2004 announced that by 2020, the EU would seek to obtain 20% of its total energy consumption requirements with renewable energy sources.

• Renewable energy with intermittent generation necessitates a change in grid operations every few minutes. With less centralized control, the need for communications and coordination has become crucial.

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Outline

1) Introduction1) Sub Ghz Radios2) Difference between AMR & AMI 3) Smart Metering

2) Standardization3) Implementation4) Conclusion

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2.4GHz vs. sub-GHz application trends

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Sub Ghz Radios

• Sub-GHz radios can offer relatively simple wireless solutions. Notable advantages over 2.4GHz radios include:– Range: transmission ranges of a kilometer or more.

– Low interference: Sub-GHz ISM bands are mostly

used for proprietary low-duty-cycle links.

– Low power: can operate uninterrupted on battery

power alone for up to 20 years.

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Difference between AMR & AMI • Automatic Meter Reading is an older

technology that only collects electrical energy consumption and transfers that data from the electric meter on the home to the utility.

• Advanced Metering Infrastructure, also known as Smart meters are updated, digital versions of the traditional electrical meter. They enables two-way communications with the meter. Consumers can use information provided by the system to change their normal consumption patterns to take advantage of lower prices.

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Smart Grid• The smart grid represents the full suite of current and

proposed responses to the challenges of electricity supply.– Reliability: fault detection, self-healing– Flexibility in network topology: bidirectional energy flows– Efficiency: Load adjustment– Sustainability: permits greater penetration of highly variable

renewable energy sources such as solar power and wind power– Market-enabling: Only the critical loads will need to pay the

peak energy prices

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Outline

1) Introduction2) Standardization

1) CENELEC2) Wireless Meter Bus3) Open Metering System

3) Implementation4) Conclusion

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CENELEC• Designated as a European Standards Organization by

the European Commission, CENELEC is a non-profit technical organization responsible for standardization in the electro-technical engineering field.

• The national standards organizations of the following countries are bound to implement European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

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Wireless Meter Bus• The Meter bus is specialized for transmitting

metering data from gas, heat, water or other meters to a data collector. It is described by European Norm:– EN 13757-1: Data exchange– EN 13757-2: Physical and link layer– EN 13757-3: Dedicated application layer– EN 13757-4: Wireless meter readout– EN 13757-5: Routing layer– EN 13757-6: Local bus

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Stack overview of M-BusManufacturer specific application

OMS DSMR

Application layer (EN-13757-3)

Routing layer (EN-13757-5) (optional)Wireless (EN-13757-4)

Data link layerPhysical layer

Wired (EN-13757-2)Data link layerPhysical layer

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Mode Direction Frequency Description

Stationary

S1 Uni-dir

868,3 MHz

The meter send data several times per day.

S1-m Uni-dirS2 Bi-dir Bi-dir version of S1

Frequent Tx

T1 Uni-dir 868,95 MHz

Send intervals of several seconds or minutes

T2 Bi-dir Bi-dir version of T1

Frequent Rx

R2

Bi-dir868.03 MHz +

n×60 kHz

Frequency multiplex allows several metering devices may be read simultaneously

Q The network topology is hierarchical

P Search procedure for discovering the path to nodes not directly reachable

Compact

C1 Uni-dir 868,95 MHz

Similar to mode T but allows higher data rate with identical energy budget and duty cyclemode T and C frames can be supported from a single receiver.C2 Bi-dir 869,525

MHzNarrow-

bandN1,N2 Uni/Bi-dir 169 MHz

Optimized for narrowband operation

Frequent Rx & Tx

F2, F2-m Bi-dir 433,82

MHzWake up message from a stationary or mobile transceiver to the meter device to open a communication channel

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Open Metering System• The application layer of Wireless M-bus can be

enhanced by extensions, being defined from vendor alliances, like the Open Metering System (OMS) Group, or from national bodies.

• The OMS group is the only system definition across Europe which integrates all media (electricity, gas, heat and water including sub-metering) into one system. It was developed by the industry in order to guarantee a future-proof communication standard and interoperability between all the meter products.

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Open Metering System

Electricity meter

Gas meter

Water meter

Heat meter Actuator Display

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MUC: Multi Utility Communication

AMM: Automated Meter Management

Primary Communication

Tertiary Communication

Collector

Back Office System

Wireless M-Bus

IPv4

Meter

Outline

1) Introduction2) Standardization3) Implementation

1) TI CC112X Transceivers2) Simplified State Diagram3) Command Strobes4) Packet Description

4) Conclusion

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TI CC112X Transceivers

• CC112X is a family of high performance low power RF transceivers designed for operation with a companion MCU.

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TI CC112X Transceivers• CC112X can be configured to achieve optimum

performance for many different applications using the SPI interface.

• The following key parameters can be programmed:– Power-down/power-up mode (SLEEP/IDLE)– Crystal oscillator power-up/power-down (IDLE/XOFF)– Receive/transmit mode (RX/TX)– Carrier frequency, Symbol rate, Modulation format, RF output

power, RX channel filter bandwidth– Data buffering with separate 128-byte RX/TX FIFOs– Enhanced Wake-On-Radio (eWOR)

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Simplified State Diagram

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TX mode

RX mode

IDLE

FIFO Error

Freq Calib

Freq Synth ON

Freq Startup

Cristal OFF

SleepSXOFF

SRX/STX/SFSTX

STX SRX

SPWD

SRX/ STX/ SFSTX/ WOR

SFTX SFRX

Command Strobes

Address Strobe Name Description

0x30 SRES Reset Chip

0x34 SRX Enable RX. Perform calibration if coming from IDLE

0x35 STX Enable RX. Perform calibration if coming from IDLE

0x36 SIDLE Exit RX/TX, turn off frequency synthesizer and exit eWOR mode if applicable

0x39 SPWD Enter SLEEP mode when CSn is de-asserted

0x3A SFRX Flush RX FIFO

0x3B SFTX Flush TX FIFO

0x3D SNOP No operation. Used to get access to the chip status.

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Packet Description

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Packet Description

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Outline

1) Introduction2) Standardization3) Implementation4) Conclusion

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Conclusion

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Thank you for your attention!

References• [1] http://www.renewgridmag.com/e107_plugins/content/content.php?content.8946

• [2] Portable and Flexible Communication Protocol Stacks for Smart Metering

Projects, JOURNAL OF ELECTRONIC SCIENCE AND TECHNOLOGY, VOL. 11, NO.

1, MARCH 2013 (Axel Sikora)

• [3] SWRU295D - Texas Instruments User’s Guide: CC112X/CC1175 Low-Power High

Performance Sub-1 GHz RF Transceivers/Transmitter

• [4] METERING INTERNATIONAL ISSUE 4 2009 - AMI & SMART METERING -

OPEN METERING SYSTEM By Peder Martin Evjen

• [5]

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