The invention relates to a single
diode open-circuit fault diagnosis and positioning method for an
aviation multi-
pulse transformer rectifier, which can effectively solve the problem that the early-stage single
diode open-circuit fault detection methods of
rectifier bridges in different types of
aviation multi-
pulse transformer rectifiers are not unified. Acquiring a direct-current component in primary /
secondary side current of the phase-shifting
transformer by using a low-pass filter, defining a direct-current component residual error of the primary side current, and judging whether a single
diode open-circuit fault occurs in a
rectifier bridge in the
aviation multi-
pulse transformer rectifier or not; if a fault occurs, comparing absolute values of direct-current components of any two phases of primary side current, and simultaneously obtaining a maximum value of absolute values of direct-current components of
secondary side current so as to judge a rectifier bridge where the fault diode is located and a phase where the fault diode is located; furthermore, whether an upper bridge arm diode or a lower bridge arm diode is in an open circuit state is judged by calculating the difference between the absolute value of the maximum value and the absolute value of the minimum value of the
secondary side current in one period, and finally the functions of diagnosis and positioning of the open-circuit fault of the single diode of the rectifier bridge in the aviation multi-pulse
transformer rectifier can be achieved. The diagnosis and positioning method is high in universality, simple and easy to implement, the direct-current component of each current can be obtained only through the low-pass filter, early faults can be found, and
safe operation of the aviation secondary power supply
system can be maintained.