Research of Noise Characteristics for 10-kV Medium-Voltage Power Lines

This paper presents experimental research on the noise characteristics performed on 10-kV overhead power lines. The frequency range of interest is from 40 kHz to 2 MHz. The results show that: 1) The noise level of the 10-kV power networks depends on the power network structure, configuration, and loads. It is often higher than that of the low-voltage power networks. The noise power spectrum density usually follows the exponential distribution. However, if the power lines cross with the lines of higher voltage class power networks, the distribution is impacted by the noise from the higher voltage power network. 2) In the 10-kV power line, the noise at the power-supply side (head side) is a little higher than that at the receiving end (tail side) whereas the noise distributes uniformly. The system impedance at the busbar absorbs some noise power. 3) The noise level of phase-to-phase coupling is usually lower than or at least not greater than those of the related two single-phase-to-ground coupling, respectively