A Sensorless Input Voltage Sharing Control for ISOP DAB Converters

This paper presents a sensorless input voltage sharing control (SIVS) method based on dual phase-shift (DPS) to achieve power balance of input-series output-parallel dualactive-bridge converters (ISOP DAB). First, the power balance mechanism of the ISOP DAB converters is analyzed and the relevant SIVS strategy is proposed. The proposed method uses a perturbation algorithm to estimate the parameters mismatch between modules. Once the parameters mismatches of the DAB modules are known, the phase shifts which achieve input voltage sharing among DAB cells are calculated. Owing to the SIVS control, the system needs no input voltage sensors, which can greatly simplify the system circuit and highly reduce the cost. Finally, simulation and experimental results show that the proposed method can effectively achieve the power balance of each DAB module.