High frequency transformer in electric traction with bidirectional DC-DC converter using customized embedded system

Abstract

In Today's scenario of Public Transportation, Railway is substantially famous and commonly adopted technology for comfortable conveyance. One of the significant concern in traditional network is exploitation of line frequency transformer as these are too bulky owing to the nature of low operating frequency. Searching for the solution, the researchers have found that the high frequency Transformer (HFT) is an apt solution for this and suitable for high power applications especially for electric traction. The line frequency is transformed into medium frequency via this HFT. The medium frequency transformer offers to two distinct roles: It provides galvanic isolation in between AC grid high-voltage and low-voltage associated to the load. The second role is it assists the IGBT switches in LCC resonant circuit to function in soft switching. In general, there are three conversion strategy followed in the HFT. In addition, a separate control strategy is applied for Rectification mode, isolation stage and inverter mode. In the traction inverter side, hybrid braking mechanism is followed to control the speed and torque of the asynchronous motor. MATLAB/SIMULINK is chosen as the software platform to substantiate the results of the recommended power electronics transformer topology. The proposed system is also evaluated through hardware on a laboratory scale prototype.