Application of set-membership estimation for open circuit fault diagnosis of PMSM inverters
ZHU Yan-fei
WANG Zhen-jie
LI Chuan-jiang
GU Ya
FANG Xuan-yu
Abstract：To improve the safety and reliability of the permanent magnet synchronous motor(PMSM)drive system,for the issue of inverter open-circuit faults,this paper proposes an inverter fault diagnosis method based on set-membership estimation.Firstly,the mathematical model of the motor drive system is established using the discrete switch signals and the continuous current state variables of the motor drive system.Subsequently,based on the current estimated by ellipsoid set-membership estimation and the actual current,the ellipsoid residual current is determined.The major semi-axis of the estimated ellipsoid is used as the upper and lower bounds of the threshold.The six types of single-tube faults can be diagnosed and located by determining whether the three-phase ellipsoid residual currents exceed these bounds.This approach ensures that the ellipsoid residual current remains within the threshold during normal system operation while reducing diagnosis time in the event of a fault.In addition,the method only requires unknown but bounded noise,and does not require partial prior knowledge of noise,thereby reducing the conservatism.Simulation comparison shows that manual threshold setting has a high dependence on setting,and the adaptive threshold diagnosis time is relatively long.The proposed method has weak threshold dependence,fast detection speed,short positioning time and high accuracy,and the diagnosis time accounts for about 8％of the current cycle.
Keywords：permanent magnet synchronous motorinverteropen-circuit fault diagnosismixed logic dynamicestima-tionellipsoid residual
Publication Date：2026-02-28
Online Publishing Date：2026-04-08(First online date of this platform, not the publication date of the document)
Pages：6( 445-450 )