Gerd Bumiller PLC / BPL –An Ideal Communication Platform For A More Intelligent Electric Grid ?

2 Application Automatic meter reading Remote control of distribution network Loss and ground circuit detection Load balancing Automatic billing and prepayment Fraud detection  like in the USA Energy management for efficient integration of alternative energy generation

3 Energy Management I State of the Art: Power plants produce on demand of customer  high peak loads Alternative power generation grows and shall be doubled until 2010 Production of solar and wind power generators (Germany today: 18 GW) depends on availability of sun and wind  Prediction of production is very difficult Production of alternative power can vary over range of several GW (Germany) within one hour only Regulation between consumption and production is still done only by traditional power plants  Less production, high standby times, low efficiency Costs for electrical energy grow dramatically

4 Energy Management II Task for tomorrow: Storage possibilities of consumer have to be used for regulation (e.g. air conditioner, heating, refrigerator, hot water generator,...) Alternative energy production has to be integrated in regulation (e.g. combined heat and power stations, biogas plant,...)  Real-Time Energy Management (EDISON, CRIS,...)  Distribution quality depends on it Key: Reliable and secure communication PLC is natural communication link (efficient and always available) Very high requirements (existing systems do not fulfil)  REMPLI offers the communication infrastructure

5 Attenuation [dB]  Frequency [MHz]  Narrow Band vs. Broadband Requirement Coverage of large areas on existing infrastructure (MV- and LV-grid) Frequency range < 500 kHz Much lower attenuation  longer distances Reduced number of repeaters  lower costs  more redundancy Narrow Band  data rate between 100 kbps... 1Mbps Regulation: FCC 15 part B No interference with SW radio Independent and parallel use with BPLC (1.5-30MHz) on one Power-Line Length profile of the attenuation models for different cable lengths in LV access network Source:M. Zimmermann, Energieverteilnetze als Zugangsmedium für Telekommunikationsdienste, Shaker Verlag, Aachen, Germany 2000

6 Independent vs. Integrated Requirements Existing protocols (IEC x, M-Bus, IEC (former 1107),...) Request / response mechanism with small package size (typ Bytes) Variable reaction time of connected equipment Different real-time and QoS requirements (switching commands vs. metering data) Application dependent redundancy requirements Guaranteed reaction time on sensor events BPLC QoS mapped for Video and VoIP Link oriented traffic Package size adapted to IP-packets  Integration in BPLC is difficult and not efficient

7 Distribution Network Topological requirements Use of MV- and LV-network  bridges Large number of participants (up to 60,000 meter/primary station) No direct link to every client  repeaters Transfer quality changes over time  dynamic channel estimation Topology of LV-network is often unknown or changes dynamically  automatic routing (inside and between networks) Meshed MV-networks with variable switch configuration  bridge routing Guaranteed reaction time and other real-time requirements  No time for reorganisation Typical structure of a 10 KV sub-stations grid, Netherlands

8 Solutions Completely independent communication packages Full dynamic range Synchronisation Channel equalisation without estimation No adaptive bit loading possible  Specialised Physical Layer Add hoc networking Single Frequency Network technology Redundant networks Time slots for multiple masters and redundant use Time synchronisation (< 1ms)  Specialised MAC and Network Layer Transportation Layer for Dynamic Routing Bridge / Access Point routing, redundancy handling  Specialised Transportation Layer  Only a complete system design fulfils requirements

9 Security Security is key requirement for nearly all applications Required Security Services Authentication Integrity Availability Requirements from PLC characteristics High packet loss (up to 10%) Small bandwidth (shared kbit/s) Limited payload (20 to 50 bytes) Special Cryptography for PLC Symmetric block ciphers (3-DES) on PLC Security Token – Smart Card Security services are integral part of communication stack

10 Conclusion Fulfill requirements with technical innovation Infrastructure for a lot of applications Coexistence with BPL Cost sensitive design  Solution on Chip Cheaper realization compared with other tech. Make alternative power generation economical  REMPLI is a real innovation ! Field trial scheduled for Q4 / 2005

11 Contacts Gerd Bumiller iAd GmbH

12 Interference / SNR Interferences at the receiver: Coloured noise Narrow band noise Impulse noise Undisturbed transmission is not possible Powerful and efficient channel coding is required