Modified Zeta Bidirectional Non-Isolated DC-DC Converter with Wide Voltage Gain for E-mobility

Abstract

Isolated and non-isolated bidirectional converters are widely used in grid and electric vehicle applications. This paper proposes a non-isolated bidirectional Zeta DC-DC converter with a high voltage gain for electric vehicles and grid applications. The modified topology is configured with a non-isolated, bidirectional step-up boost converter. The zeta-modified structure can operate in either Mode-I (discharging) or Mode-II (charging) mode. For verifying its performance, the model is constructed and simulated on the PLECS platform using battery energy storage systems (BESS) as input and loaded with resistive and BLDC loads. The steady-state analysis is used to figure out the transfer function for the proposed converter. The transfer function is then tuned to get the desired response under different loading conditions. The proposed topology of the modified Zeta bidirectional DC-DC converter is then implemented in a real-time environment utilizing Opal-RT hardware. Finally, a 120V converter output with a high step-up is validated with controller parameter tuning under lesser duty with less current ripple. The features above are designed, analyzed, and validated for high-power applications with experimental results.