Assessment of emission and signal propagation in electrical power systems in the

2 - 150 kilohertz range MO-AM3-2

Anders Larsson, Luleå University of Technology, Sweden

Outline of the presentation• Signal emitting equipment

• Measurement equipment

• Long term measurement

• High frequency components

• Emissions fluorescent lamps powered by HF-ballast

• Summary

Grid

EMC filter Rectifier Smoothing capacitor

Chopper Transformer Rectifier

Load

Active PFC

Some signal emitting equipment in the frequency range from 2 to 150 kHz

SMPS

Power line communication

Power Meter

Concentrator

Diversity of current drawn by equipment

Resulting harmonic spectra

20 40 60 80 100 120 1400

5x 10

-3 Adjustable speed drive

20 40 60 80 100 120 1400

5x 10

-3 CFL 11 W

20 40 60 80 100 120 1400

1

2x 10

-3 Laptop

Cur

rent

(R

MS

)

20 40 60 80 100 120 1400

0.005

0.01LCD-TV

20 40 60 80 100 120 1400

1

2

x 10-4 VCR

20 40 60 80 100 120 1400

5x 10

-3 CRT-TV

20 40 60 80 100 120 1400

0.5

1

1.5x 10

-3 Mobile charger

20 40 60 80 100 120 1400

1

2x 10

-3 Incandescent lamp 100 W

Frequency (kHz)

Resulting spectra 2 to 150 kHz

Hzb

Hzbffb CG

100

95

2

IEC 61000-4-7

Measurement at a house containing both electronic equipment together with PLC

20 40 60 80 100 120 1400

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Vol

tage

Frequency (kHz)

Induction cooker

PLC

Measuring and analyzing technology, 2 to 150 kHz

Instrumentation

Measuring receivers

PQ instruments

Oscilloscopes

Memory recordersCurrent and voltage

probes

0 20 40 60 80 100 120 140 160 180 200-200

-150

-100

-50

0

50

100

150

200

Ma

gn

itud

e

Time (ms)

Time-domain

Short Time Fourier Transform (STFT)

))102sin(405002cos(25

otherwise 0

1000 if )4002cos(50

)2002cos(100

3

2

1

tttf

mstttf

ttf

0 200 400 600 800 1000 12000

10

20

30

40

50

60

70

80

Frequency (Hz)

Resulting spectra

Short Time Fourier Transform (STFT)

Time (s)

Fre

quen

cy (

Hz)

Spectrogram

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.20

200

400

600

800

1000

1200

Measurement on fluorescent lamps

Long-term measurements where carried out in different locations:

0 20 40 60 80 100 120 140 160 180 200-1

-0.5

0

0.5

1C

urr

ent

(A)

Fluorescent lamp

0 5 10 15 20 25 30-1

-0.5

0

0.5

1

Cu

rren

t (A

)

Time (ms)

0 5 10 15 20 25 30 35 40

-0.2

-0.1

0

0.1

0.2

0.3

Cur

rent

(A

)

Fluorescent lamp

Time (ms)

20 40 60 80 100 120 1400

2

4

6x 10

-3

Cur

rent

(R

MS

)

Frequency (kHz)

0 10 20 30 40 50 60-1

0

1

Time (ms)

0 5

x 10-3

0

20

40

60

80

100

120

140

160

180

200

Time (ms)

Fre

quen

cy (

kHz)

0 10 20 30 40 50 600

20

40

60

80

100

120

140

160

180

200STFT

0 20 40 60-1

0

11

0 20 40 60-1

0

12

0 20 40 60-1

0

13

0 20 40 60-1

0

14

0 20 40 60-1

0

1

Cur

rent

(A

)

5

0 20 40 60-1

0

16

0 20 40 60-1

0

17

Time (ms)

0 20 40 60-1

0

18

1

0 10 20 30

50

100

1502

0 10 20 30

50

100

150F

requ

ency

(kH

z)

3

0 10 20 30

50

100

1504

0 10 20 30

50

100

150

5

0 10 20 30

50

100

1506

0 10 20 30

50

100

150

7

0 10 20 30

50

100

150

Time (ms)

8

0 10 20 30

50

100

150

0 to 48 lamps project

Spreading of components in the range of 2 to 150 kHz

1

2

3 ….12

Feeding cable

Itot and U is measured

Individual lamp current is also measured

Measurement setup

Voltage spectrum (n)

Frequency (kHz)

n (la

mps

)

20 40 60 80 100 120 1400

5

10

15

20

25

30

35

40

45

Primary emission

Secondary emission

Resulting voltage spectrums

Total current spectrum (n)

Frequency (kHz)

n (la

mps

)

20 40 60 80 100 120 140

5

10

15

20

25

30

35

40

45

Resulting total current spectrums

Current spectrum for one lamp (n)

Frequency (kHz)

n (la

mps

)

20 40 60 80 100 120 1400

5

10

15

20

25

30

35

40

45

Resulting lamp current spectrums

0 5 10 15 20 25 30 35 40 450

0.1

0.2

0.3

0.4

0.5

0.6

Cur

rent

(A

)

n (lamps)

Max value of current above 2 kHz from 9.5 to 11 ms into the window

What about the recurrent oscillations?

Peak amplitude of Itot

5 10 15 20 25 30 35 40 451

1.5

2

2.5

3

3.5

Fre

quen

cy (

kHz)

n (lamps)

Frequency according to ESPRIT

Summary• Most of the distortion in this frequency range can be classified into:

• Narrowband components

• Broadband components

• Recurrent oscillations

• Our experience is that PLC generates the highest levels of emission in this frequency range in the LV power systems

• The emission from different ballast varies

Cont->

• When this equipment is installed in large numbers the components aggregate in different ways. This impacts how emission standards should be carried out

• The use of time-domain sampling instruments should be used even for the frequency range 9 – 150 kHz

• Different analyzing tools are needed to detect and quantify different components. It is shown that not only one analyzing tool should be used to disclose and describe different components in the measured signal

• Work is needed to close the gap in emission, compatibility and immunity standards

Further reading

• Larsson, A & Bollen, M 2009, 'Emission and immunity of equipment in the frequency range 2 to 150 kHz', i L Toma & B Otomega (red), 2009 IEEE Bucharest PowerTech Proceedings, IEEE, Piscataway, N.J., s. 2325-2329.

• Rönnberg, S, Wahlberg, M, Bollen, M, Larsson, A & Lundmark, M 2009, 'Measurement of interaction between equipment in the frequency range 9 to 95 kHz', CIRED 20th International Conference on Electricity Distribution, I E T Conference Publication Series, The Institution of Engineering and Technology, s. 231-234.

• Bollen, M, Ribeiro, P, Larsson, A & Lundmark, M 2008, 'Limits for voltage distortion in the frequency range 2 to 9 kHz', I E E E Transactions on Power Delivery, vol 23, nr 3, s. 1481-1487.

• Larsson, A, Bollen, M, Wahlberg, M, Lundmark, M & Rönnberg, S 2010, 'Measurements of high-frequency (2-150 kHz) distortion in low-voltage networks', I E E E Transactions on Power Delivery, vol 25, nr 3, s. 1749 - 1757.

• Larsson, A & Bollen, M 2010, 'Measurement result from 1 to 48 fluorescent lamps in the frequency range 2 to 150 kHz', 14th International Conference on Harmonics and Quality of Power (ICHQP), IEEE, Piscataway, NJ .

• Larsson, A 2011, On high-frequency distortion in low-voltage power systems, Doctoral thesis / Luleå University of Technology, Luleå tekniska universitet, Luleå.

Biography – Dr. Anders Larsson

• 2011 – Lecture, Luleå University of Technology

• 2011 – Ph.D, Luleå University of Technology

• 2007 – Licentiate degree, Luleå University of Technology