| 摘要 |
PURPOSE: To monitor the temperature of an electric line to be monitored by detecting the temperature itself from the detected results of conduction current without measuring the temperature of the electric line by finding the temperature of the electric line by adding a temperature difference to the set surface temperature value of the electric line responding to the air temperature. CONSTITUTION: After initialization (i), a interval Δt is counted (ii) and the data about conduction current In and air temperature QA are fetched through sampling after the interval Δt has elapsed (iii). Then, the quantities of generated heat Qi, and Qs are found (iv) and estimated values Qin and Qsn of the internal temperature and surface temperature of an electric line to be monitored are found by calculation (v). Thereafter, the temperature Qn of the electric line is found by adding the difference Qin-Qsn between the estimated temperatures Qin and Qsn to the set surface temperature value of the electric line (vi). In addition, the abnormal overheating of the electric line is monitored by making the temperature Qn of the electric line ineffective until Δt.N has elapsed after the start is informed and making the temperature Qn effective after the Δt.N has elapsed (vii). Moreover, a monitoring control command, maintenance information, etc., are outputted based on the monitored results (viii). |
