Design and implementation of a multi-port bidirectional converter for electric vehicle applications

This article proposes a new multi-port bidirectional DC-DC converter for electric vehicle (EV) usages. The recommended converter has the ability for step-up and step-down operating. The bidirectional power flow makes the proposed converter suitable for EV applications, where a storage unit is charged and discharged. The proposed converter has three ports (V_High, V_Low, and V₂), and all of these ports have bidirectional features. In each operation mode (step-up or step-down), the output port is loaded by two independent input sources. Also, a high voltage conversion ratio is achieved with low power switches duty cycle and reduced peak voltage over semiconductors. Input current with reduced ripple, low components count, a simple circuit with low cost and volume, and high efficiency are the main advantages of the presented bidirectional topology. In order to demonstrate the performance and effectiveness of the recommended converter, operational and steady-state analysis in step-up and step-down modes, design consideration, efficiency calculation, and comparison with other DC-DC converters are provided Finally, a prototype with a step-up power of 120 W and a step-down power of 30 W is created, and experimental data are shown to validate the numerical investigations.