Open AccessGround Leakage Current Caused by Common-Mode Voltage of PWM inverter
Author(s) -
J. Szymański,
Marta Żurek-Mortka
Publication year - 2020
Publication title -
transengin
Language(s) - English
Resource type - Journals
eISSN - 2658-2120
pISSN - 2658-1698
DOI - 10.24136/tren.2019.002
Subject(s) - pulse width modulation , parasitic capacitance , voltage , harmonics , common mode signal , inverter , three phase , electrical engineering , capacitance , physics , engineering , materials science , electrode , quantum mechanics , digital signal processing , analog signal
In railway tractive vehicles, three-phase PWM (Pulse Width Modulation) inverters generate parasitic Differential-Mode Voltages (DMV) and Common-Mode Voltages (CMV). Parasitic voltages are a side effect of using the width modulation to shape the phase-to-phase inverter’s voltage. In this article, the authors present a mathematical description of the DM and CM voltages and carry out their spectral analysis. Based on the spectral harmonics analysis, the authors present a method for filtration of harmonics of DM and CM voltages aimed at limiting the capacitance parasitic currents: due to DM voltage – phase-to-phase parasitic current and CM voltage – ground parasitic currents. As the final result of the tests, almost complete elimination of leakage parasitic current form PE shock protection system was achieved.