Abstract:
Electromagnetic radiation environment were measured in winch distribution room of coal mine underground during starting, running and stopping of winches by use of R&S spectrum analyzer FSP7 and 9 kHz~7 GHz electric field antenna. Following conclusions were gotten after analyzing the measured data: (1) The EMI is produced in the entire frequency band when hydraulic winches start. The EMI is very strong in individual band which is 40 dB?μV/m more than the ones in normal running. The EMI is very small during normal running and stopping of hydraulic winches. (2) The EMI is very strong during running, starting and stopping of frequency-conversion winches of wire rope. The measured value of EMI is fundamental same at 1 m, 1.7 m height. The EMI in low-frequency is very large and the maximum EMI achieves 170 dB?μV/m, which is 80 dB?μV/m more than the corresponding background noise. (3) The EMI during running, starting and stopping of frequency-conversion winches of wire rope is more than the one of hydraulic winches in the same processes.