BSI PD CISPR/TR 18-2:2010
$215.11
Radio interference characteristics of overhead power lines and high-voltage equipment – Methods of measurement and procedure for determining limits
| Published By | Publication Date | Number of Pages |
| BSI | 2010 | 76 |
This part of CISPR 18, which is a technical report, applies to radio noise from overhead power lines and high-voltage equipment which may cause interference to radio reception.
The frequency range covered is 0,15 MHz to 300 MHz.
A general procedure for establishing the limits of the radio noise field from the power lines and equipment is recommended, together with typical values as examples, and methods of measurement.
The clause on limits concentrates on the low frequency and medium frequency bands and it is only in these bands where ample evidence, based on established practice, is available. No examples of limits to protect radio reception in the frequency band 30 MHz to 300 MHz have been given, as measuring methods and certain other aspects of the problems in this band have not yet been fully resolved. Site measurements and service experience have shown that levels of noise from power lines at frequencies higher than 300 MHz are so low that interference is unlikely to be caused to television reception.
The values of limits given as examples are calculated to provide a reasonable degree of protection to the reception of broadcasting at the boundary of the recognized service areas of the appropriate transmitters in the radio frequency bands used for a.m. broadcasting, in the least favourable conditions likely to be generally encountered. These limits are intended to provide guidance at the planning stage of the line and national standards or other specifications against which the performance of the line may be checked after construction and during its useful life.
The measuring apparatus and methods used for checking compliance with limits should comply with the respective CISPR specifications, as e.g. the basic standards series CISPR 16, see [1]*.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 4 | CONTENTS |
| 8 | FOREWORD |
| 10 | INTRODUCTION |
| 12 | 1 Scope 2 Normative references |
| 13 | 3 Terms and definitions 4 Measurements 4.1 Measuring instruments |
| 14 | 4.2 On-site measurements on HV overhead power lines |
| 17 | 4.3 Statistical evaluation of the radio noise level of a line |
| 18 | 4.4 Additional information to be given in the report 4.5 Measurements on HV equipment in the laboratory Tables Table 1 – Number of n sets of measurement of the radio noise level and corresponding values for factor k |
| 26 | 5 Methods for derivation of limits for HV power systems 5.1 Overview 5.2 Significance of CISPR limits for power lines |
| 27 | 5.3 Technical considerations for derivation of limits for lines |
| 29 | Table 2 – Minimum usable broadcast signal field strengths in the v.h.f bands according to CCIR |
| 32 | 5.4 Methods of determining compliance of measured data with limits |
| 34 | 5.5 Examples for derivation of limits in the frequency range below 30 MHz |
| 36 | 5.6 Additional remarks 5.7 Technical considerations for derivation of limits for line equipment and HVAC substations |
| 39 | 6 Methods for derivation of limits for the radio noise produced by insulator sets 6.1 General considerations 6.2 Insulator types |
| 40 | 6.3 Influence of insulator surface conditions |
| 41 | 6.4 Criteria for setting up radio noise limits for insulators |
| 42 | 6.5 Recommendations |
| 44 | 7 Methods for derivation of limits for the radio noise due to HVDC converter stations and similar installations 7.1 General considerations Table 3 – Recommendations for the radio noise voltage limits and for the test methods for insulator sets installed in different areas |
| 45 | 7.2 Sources of interference |
| 46 | 7.3 Radiated fields from valve halls |
| 47 | 7.4 Conducted interference along the transmission lines |
| 48 | 7.5 General criteria for stating limits |
| 50 | 8 Figures Figures Figure 1 – Transformation of pulses through a CISPR measuring receiver |
| 51 | Figure 2 – Bursts of corona pulses generated by alternating voltage Figure 3 – Example of extrapolation to determine the radio noise field strength reference level of a power line, here at the direct reference distance of 20 m |
| 52 | Figure 4 – Basic test circuit Figure 5 – Standard test circuit |
| 53 | Figure 6 – Connection to the measuring receiver by a coaxial cable Figure 7 – Connection to the measuring receiver by a balanced cable Figure 8 – Special test circuit |
| 54 | Figure 9 – Arrangement for calibration of the standard test circuit |
| 55 | Figure 10 – Map showing boundaries of zones A, B, and C in regions 1 and 3 |
| 56 | Figure 11 – Illustration of the four basic parameters for a power transmission line |
| 57 | Figure 12 – Example of typical statistical yearly “all-weather” distributions of the radio-noise levels of a bipolar direct current line (—–) and for an alternating current line in a moderate climate (- – -) |
| 58 | Figure 13 – Example of radio noise voltage level V, as a function of the relative air humidity R.H., in clean conditions and slightly polluted conditions, of a standard insulator (—–) and a particular type of “low noise” insulator (- – -) Figure 14 – Example of frequency spectra of pulses with different rise times, simulating commutation phenomena in mercury valves and in thyristor valves |
| 59 | Figure 15 – Example of frequency spectra of the radio interference recorded outside the hall of a mercury arc valve converter station with and without toroidal filters Figure 16 – Example of frequency spectra of the radio interference recorded outside the hall of a thyristor valve converter station for different operating conditions |
| 60 | Figure 17 – Attenuation of the field strength as a function of the distance on a horizontal plane, for different frequencies |
| 61 | Figure 18 – Example of frequency spectrum of the radio interference in the vicinity of a d.c. line (30 m) at a short distance from the converter station |
| 62 | Figure 19 – Example of frequency spectrum of the radio interference in the vicinity of an a.c. line (20 m) at a short distance from the converter station Figure 20 – Frequency spectra of radio interference at 20 m from the electrode line at 1,5 km from the Gotland HVDC link in Sweden with mercury arc groups or thyristor groups in operation |
| 63 | Figure 21 – Frequency spectra of radio interference at 20 m from the electrode line at 1,5 km and 4,5 km from the Gotland HVDC link in Sweden with mercury arc groups in operation Figure 22 – Frequency spectra of the radio interference recorded along a 200 kV d.c. line, at 20 m from the conductor, at different distances from the converter station |
| 64 | Annex A (informative) Radio interference measuring apparatus differing from the CISPR basic standard instruments |
| 65 | Annex B (normative) List of additional information to be included in the report on the results of measurements on operational lines |
| 66 | Annex C (informative) Minimum broadcast signal levels to be protected – ITU recommendations Table C.1 – Minimum field strength Table C.2 – Nominal usable field strength |
| 67 | Annex D (informative) Minimum broadcast signals to be protected – North American standards Table D.1 – Signal levels at the edge of the service area in North America |
| 68 | Annex E (informative) Required signal-to-noise ratios for satisfactory reception Table E.1 – Summary of signal-to-noise ratios for corona from a.c. lines (Signal measured with average detector, noise measured with quasi-peak detector) |
| 69 | Table E.2 – Quality of radio reception or degree of annoyance due to RFI |
| 71 | Annex F (informative) Derivation of the formula for the protected distance |
| 72 | Bibliography |
