With the large-scale promotion of distributed photovoltaic

it is necessary to study the impact of distributed photovoltaic access to distribution network on voltage

current and relay protection. Firstly

according to the typical structure of distributed photovoltaic and distribution network

the simulation model of distributed photovoltaic access to distribution network is established based on RTDS. Secondly

the influence of distributed photovoltaic on distribution network voltage and current under different photovoltaic permeability

fault type and fault location is simulated and analyzed. Then

the influence of distributed photovoltaic on distribution network relay protection under power grid fault state is studied. The simulation results show that after the distributed photovoltaic is connected to the distribution network

the voltage increases and the current provided by the system decreases. When the distributed photovoltaic permeability is large

the overcurrent protection may refuse to operate and the reclosing may fail. Therefore

the protection setting needs to be reset.