Photovoltaic (PV) power generation has been rapidly adopted, but these systems can lead to AC or DC interference that may damage nearby pipelines. In this study, the factors affecting this electromagnetic interference were comprehensively explored through numerical simulations. In the instance of a 160 MW PV power plant, the interference risks to pipelines were assessed. The research results show that although leakage current from PV modules can cause DC interference, its effect on pipelines was found to be negligible. However, steady-state electromagnetic coupling interference due to the buried cables and overhead lines of the PV power generation system does pose a risk to pipeline integrity that is influenced by multiple factors. The primary factor is the phase current imbalance, current amplitude, parallel length, and parallel spacing. A risk to pipelines due to single-phase fault currents was also discovered, but this risk can be mitigated by increasing the scale of the PV grounding. This study established a regression formula between the withstand voltage of pipeline coatings, the continuous arc distance of grounding bodies, the risk of pipeline erosion, and the grounding resistance of photovoltaic fields through numerical simulation. The regression formula can guide the design of lightning protection performance of photovoltaic fields for pipelines. To ensure pipeline safety, the withstand voltage of pipeline coating should be lower than the safety limit, the safety spacing between pipeline and PV grounding should be greater than the continuous arc distance of lightning current, and the risk of pipeline erosion should meet the strength requirements of the pipeline. In a case study, a 160-MW PV power plant caused a deviation in pipeline DC potential of less than 5 mV, whereas the maximum AC interference current density of the pipeline reached 67 A/m2.