1.1.PLC Field trial in ArnhemPLC Field trial in Arnhem The NetherlandsThe Netherlands

2. 2. Radiating characteristics of Radiating characteristics of LLowow VVoltage oltage DDistribution istribution NetworksNetworks

Experiments related to network issuesExperiments related to network issues

PLC Field trial in the city of Arnhem, NL

• Start 2002, end May 2003Start 2002, end May 2003

• 150 houses; 150 houses;

• 337 modems (included repeaters)337 modems (included repeaters)

• 2 Mbit/s backbone via 6 medium 2 Mbit/s backbone via 6 medium voltage transformer stations. voltage transformer stations. (35 users (35 users per transformer station)per transformer station)

• Modem power density -50 dBm/Hz; Modem power density -50 dBm/Hz;

• DDSSS TechnologySSS Technology

Operator results (Arnhem)

• Users very satisfied with service,Users very satisfied with service,• Technology works,Technology works,• Commercially not yet viable!Commercially not yet viable!• Practical 1,4 Mbit/s too slow for future,Practical 1,4 Mbit/s too slow for future,• Connecting 10 kV Transformers to Connecting 10 kV Transformers to

infrastructure a logistic/economical infrastructure a logistic/economical problem, (40.000 Transformer stations problem, (40.000 Transformer stations to be connected).to be connected).

Results measurements in Arnhem

• Large variations in generated fields (30 to 40 dB) Large variations in generated fields (30 to 40 dB) • Generated Fields:Generated Fields:

– Table ATable A (JWG Questionnaire Option 2) (JWG Questionnaire Option 2):: pass pass

– Table B Table B (JWG Questionnaire Option 3)(JWG Questionnaire Option 3) NB 30: NB 30: fail fail

• A few hundreds of meters from the PLC- area the A few hundreds of meters from the PLC- area the generated fields are below ‘ITU rural’ noise level. generated fields are below ‘ITU rural’ noise level.

• How many measurements are needed to assess the How many measurements are needed to assess the network compliance?network compliance?

2. Additional measurement 2. Additional measurement campaigncampaign

Radiating characteristics of LRadiating characteristics of Low ow VVoltage oltage DDistribution Networks istribution Networks LVDNLVDN’s’s

Radiating characteristics of LVDN’s

• Voltage injection on mains wires (sym. and asym) Voltage injection on mains wires (sym. and asym) • E and H–field measurements in and around E and H–field measurements in and around

40 different houses:40 different houses:– Indoor: At 1 m and 3 m from injection point Indoor: At 1 m and 3 m from injection point

– Outdoor: At 3 m, 10 m, 100 m and 1000 m from Outdoor: At 3 m, 10 m, 100 m and 1000 m from building building

• ‘‘Antenna gain’ measurements of Antenna gain’ measurements of LVDN’s.LVDN’s.

Results

• Large variations in generated fields (>40 dB)Large variations in generated fields (>40 dB)because of large variations in mains geometry because of large variations in mains geometry

• The injection of voltages equal to the CISPR-22 The injection of voltages equal to the CISPR-22 class B mains voltage limits class B mains voltage limits cancan result in result in magnetic field levels equal to the ‘table A’ field magnetic field levels equal to the ‘table A’ field limits at 3 m distance. limits at 3 m distance. However, in most cases the generated fields will However, in most cases the generated fields will be lower than the ‘table A’ limits.be lower than the ‘table A’ limits.

General conclusions

• Local effects arise at locations in and around the PLC area. Further outside the PLC area fields will be lower than the existing noisefloor.

BUT, the following phenomena is underestimated:

• If in a large part of the world PLC networks are deployed with a large penetration rate, cumulative effects cause a rise in the noise floor in a large area (not near PLC systems!) (Applies << 50 MHz)

Conclusions Local PLC- effects are well known and can

be controlled in some manner

Groundwave

Direct wave

Near LVDN wires

In and around

PLC-area

Above PLC-area

Near field ‘coupling’

Mondial PLC effects depend on deployment and penetration rate!

Skywave Skywave Rise of noise floor Rise of noise floor

Measured equivalent antenna gain (for sky wave) of LVDN’s in the frequency range 5 MHz- 20 MHz amounts on average -30 dBi.