Effect Produced on Electromagnetic Leakage in PLC by Indoor Power line Arrangements

摘要

The effect of electric field strength leakage produced when short wave band PLC is impressed on indoor power lines is mainly dependent on the balance of indoor power lines. When the present balance sample values of indoor power lines, collected in Europe, America and Japan are observed, as far as average values are seen, the values are not bad compared with those of communication lines but there are cases where locally, the balance becomes extremely bad and the electric field strength which leaks from such parts becomes large. However with PLC that uses short wave bands from 1 MHz to 30 MHz, its resonance wavelength is longer than those of indoor power lines and therefore the electric field strength leakage differs from the energy sum of the local electromagnetic wave leakage. By making a model house by deeming the entire house a short wave antenna, it is believed that the electric field strength leakage produced by impressing a short wave band PLC signal on a detached house can be estimated but the wiring form of indoor power lines is extremely complicated and since the form, number of branches, wiring method differ by house, it is difficult to make a house a model. Therefore, in this paper, with the object of gathering basic data to estimate the leaked electric field strength when a short wave PLC is introduced to a general detached house, measurements were taken of the changes in electric field strength leakage by short wave band PLC signals with changes in balance resulting from various simple indoor power lines.