A Generalized Modulation Scheme for Soft Switched Dual Active Bridge Converter With Wide Voltage and Power Ranges

Bidirectional power conversion with wide voltage and power range is important for various applications such as renewable source and energy storage integration, automotive applications etc. Dual active bridge converter is a good candidate for its ease of control and reliability. Modulating the phase shifted PWM for dual active bridge is a very important part of deign and can be used to achieve better performances such as soft switching, control of rms current etc. Out of many proposed modulation scheme, triangular modulation stands out to be highly efficient scheme, however it suffers from low power flow range and limitations on output and input voltage ratio. In this paper, a new modulation scheme is proposed which allows higher power flow range without any limitation on the voltage gain, at the same time retaining majority of loss less switching properties similar to triangular modulation scheme. Thus, improving converter power density significantly. Simulation and experimental results confirms the performance of the modulation scheme.