Stability Characterization of ADRC-Controlled DAB Converters Supplying Constant Power Loads

Analyzing the stability of dual-active bridge (DAB) converters is of great significance for ensuring the reliable system operation. The introduction of active disturbance rejection control (ADRC) presents new challenges in the stability analysis of DAB converters, while constant power loads (CPLs), with negative impedance characteristics, further complicate the design of system parameters. These challenges have not been thoroughly explored. To address these issues, this article proposes a model of a DAB converter controlled by ADRC and supplying a CPL. A small-signal analysis is conducted using Lyapunov’s first method, complemented by numerical simulation verification. The maximum permissible step change in load power is estimated using numerical simulation, with results validated by estimating the system’s asymptotically stable region. Parameter design strategies are also discussed to enhance both small-signal and large-signal stabilities. Finally, the experimental verification is performed, and valuable conclusions are given.