Objective To examine the intensity changes in electric field and magnetic field in driver compartment after rail speed increase and the electrification reform of locomotives.
Methods The observation group was composed of three electric locomotive models running Lanzhou-Jiangyuguan Pass route, while the control group was composed of three diesel locomotive models running Jiangyuguan Pass-Liuyuan route. Totally 11 sampling sites in driver compartments were selected to monitor and record electric and magnetic field intensities. At least three trains were monitored per locomotive model and each train was measured at least three by combinations of location, speed, and operation condition. All measurement and evaluation were performed according to the Health standard for electric field in the work environment (GB 16203-1996) and Limits and test methods for exposure to electromagnetic field (draft).
Results The qualification rates of electromagnetic radiation at the key positions such as the head of drivers were all 100% in the selected compartments. The difference in electric field intensity between the electric locomotives and the diesel locomotives was significant statistically (H=0, P<0.01), and the intensity of magnetic field in the electric locomotives was also higher than that in the diesel locomotives (H=0, P<0.001). A strong positive correlation was found between the intensity of magnetic field and the traction power of locomotive (r=0.9401, P<0.005), and mainly concentrated around the steel structure of the compartments, but such correlation was relatively lower at the key positions such as the head of drivers (P<0.01).
Conclusion The intensity values of electromagnetic field at the key positions of drivers of electric locomotives are lower than the relevant national occupational limits or the limits derived from the draft. The intensity of electromagnetic field in driver compartments of electric locomotives are mainly affected by overhead lines, surface electrostatic field from running trains at high speed, and electromagnetic field from the electrical equipment of locomotives. That locomotives running at waved speeds and being "powered" frequently could increase the intensity of electromagnetic field in driver compartments.
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