Abstract: Aiming at the problem that the detection accuracy decreases due to inaccurate measured data caused by sensor disturbances in the detection process of the open-circuit fault diagnosis method, this paper proposes an open-circuit fault detection method for converters based on sensor disturbance compensation. This method realizes the preliminary detection of open-circuit faults by establishing a DC voltage observer model and fault characteristic function. Based on the H∞ theory, a sensor measurement observer is designed, a disturbance characteristic function is constructed for disturbance detection and location. A disturbance compensation link is introduced into the original fault characteristic function to achieve accurate and robust detection. The method verification and comparative analysis are carried out on the MATLAB/Simulink simulation platform.