This paper studies the incipient fault after the completion of the home-produced Genan HVDC control and protection system.It is found that the mismatch between reactive power control and AC filter protection in Gezhouba converter station led to an out of service fault of the Genan HVDC
and one bug in active power control software is also discovered.Some corresponding methods are put forward for the better accomplishment of the home-produced HVDC control and protection system.