An Open-Circuit Fault Diagnosis And Location Method For Dual Active Bridge DC/DC Converter

Abstract

Dual active bridge (DAB) dc-dc converter has been obviously attracting more research interests in recent years. Considering the reliability of DAB is very significant, in this paper, we propose a fault diagnosis and location method for insulated gate bipolar transistor (IGBT) open-circuit fault. By analysing the operating modes and waveforms of DAB converter when IGBT occurs open-circuit fault, the inductance current and midpoint voltage of bridge arm are selected as the fault features to detect the faulty IGBT. The proposed method needs only one current sensor and two voltage sensors to reduce hardware costs compared with the existing method. The whole diagnosis process is also given in detail. Finally, the DAB converter model with the proposed fault diagnosis and location method is simulated in PLECS to verify its accuracy.