Abstract
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.
Highlights
Ground currents of high frequency disturbances are caused by the common-mode voltage (CM) uCM of the inverter
In IT system of the industrial power supply system the ground leakage current flows through the parasitic capacitances between the ground and the ungrounded star connection of the transformer’s secondary windings
In an industrial power system with an IT transformer network type, the CM voltage of the inverter, which is deposited on the parasitic capacitances between the ground and the ungrounded star connection of the secondary windings of the transformer, causes high frequency disturbances of voltages in transformer
Summary
Ground currents of high frequency disturbances are caused by the common-mode voltage (CM) uCM of the inverter. Isolationground) system (or High Resistance Grounded network HGR) of the industrial power supply system the ground leakage current flows through the parasitic capacitances between the ground and the ungrounded star connection of the transformer’s secondary windings. In an industrial power system with an IT transformer network type, the CM voltage of the inverter, which is deposited on the parasitic capacitances between the ground and the ungrounded star connection of the secondary windings of the transformer, causes high frequency disturbances of voltages in transformer. In the final part of paper, a power supply system for the traction drive was proposed, in which high frequency disturbance currents created as a result of CM and DM voltage by PWM inverters were eliminated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
