Different from fault characteristics of the traditional generator
photovoltaic (PV) generator will affect the action of conventional power directional components of a distribution system
making the components unable to judge the fault direction correctly. This paper studies the fault characteristics of the PV generator by deriving the relationship between positive fault current phase and normal voltage phase during forward direction and negative direction fault. A new directional component theory is proposed as a result
which guarantees the action reliability of the directional component during various types of fault at different places of the distribution system while avoiding the voltage dead zone of traditional power directional components. The theory is verified by simulation.