The long-sequence hourly photovoltaic power simulation sequence is an important reference information in the stage of power station planning, designing and dispatching operation. Based on the ERA5 reanalysis data, this paper adopts the tilted plane radiation model and the photoelectric conversion model to construct a photovoltaic power physical simulation model, and conducts hourly power simulation study for a total of 23 years from 2000 to 2022 for 30 existing photovoltaic power stations in China, and analyzes the simulation effect and the interannual volatility of power generation capacity in different temporal and spatial ranges. The results show that: on different time scales, the power simulation results are different, and the long time scale is better than the short time scale. The root mean square errors of the monthly average, daily average and hourly scales are 0.89–20.8, 0.43–9.61, and 0.3–3.42 respectively; in different spatial ranges, the power simulation results are also different, and the power stations with relatively low simulation effect are mainly distributed in the western region with smaller longitude; there are great differences in the interannual power generation capacity volatility of each power station, and the volatility between years of the power stations at low latitudes is relatively large. In general, the power simulation result of the ERA5 reanalysis data can better reflect the actual operation law of the power station, and carrying out long-sequence power simulation through the ERA5 reanalysis data can provide relatively reliable data support for the planning and operation of the power station.