| 摘要 |
Epidemiological surveys show that the risk of suffering from childhood leukemia in places near high-voltage power transmission lines is high. Relevant data and material have been collected and analyzed, with the result that the major factor of the high risk of childhood leukemia is ultraviolet radiation (particularly UV-B, UV-C) generated by corona discharge from high-voltage transmission lines. An electric power system for stably supplying power while suppressing corona discharge generating ultraviolet radiation which may cause health problems of human beings is provided. The voltage at which corona discharge starts varies with weather. Data on weather forecast is inputted for each district every certain time so as to calculate the corona discharge start estimated voltage for each transmission line with a computer. If the calculation result predicts occurrence of corona discharge at normal transmission voltage, the transition voltage is lowered or the power transmission through the transmission line is stopped. Another method of solving the problem is to install corona discharge detecting means on transmission lines near the places where human beings reside. If the means detects corona discharge, the transmission voltage is lowered, or the transmission through the transmission line stopped. |
