The invention discloses a transient fault ride-through control method of a high-
voltage frequency converter. The method comprises the following steps: an output current value of the frequency converter is sampled in real time; if the output current value is greater than a set protection value, the
operating frequency and an output
voltage of the frequency converter are set to the lowest value, so that the output
voltage of the frequency converter is rapidly reduced, and a motor
stator current is also rapidly reduced so to prevent the
stator current from rising to a shutdown protection value and causing a halt, thereby realizing fault ride-through; then, through automatic flexible
recovery, the output voltage and frequency of the motor rise, and the pressure of a
hydraulic pump of a well-wall corer gets recovered; and a
drill bit can continue drilling to realize the fault ride-through. The invention also provides the
system of realizing the above method. According to the invention, when the current of a sticking
stator surges, the current is reduced to be in a safety scope to avoid occurrence of protective shutdown, and flexible automatic
recovery can be realized so that a continuous power can be provided for timely
drill withdrawing and subsequent drilling when sticking of drilling of the well-wall corer occurs.