A Simplified Large-Signal Model-Based Control for Dual Active Bridge Series Resonant Converter to Achieve Uniform Dynamic Response

The control of dual active bridge series resonant converter (DABSRC) has been widely researched in the literature for various applications, including pulsed-power-load (PPL). Numerous phase-shift and frequency modulation schemes help DABSRC achieve output voltage regulation along with reactive power control. In case of PPL applications, a fast and uniform transient response is desired for both the output voltage and the reactive power in the high-frequency link due to frequent loading. This requirement is broadly fulfilled through linearized and nonlinear control methods. A large-signal model-based control (LSMC) is proposed in this article, which achieves a uniform transient response throughout the operating range, unlike the small-signal model-based linearized multivariable control. The proposed LSMC method eliminates the operating point dependency through a lucid control methodology combining analog and digital blocks. The decoupling in multivariable control and system order reduction is achieved through the feedforward technique. This method also reduces the computational burden time of the controller as compared to the existing nonlinear control methods. The achieved settling time for both output voltage and reactive power is 5 ms with a computational burden of 5.6 mu s. The experimental validations are performed on a 2.4 kW DABSRC hardware prototype.