Abstract: With the integration of large scale renewable energy, its volatility and uncertainty have brought great challenges to the power system. To fully reflect and deal with its characteristics, this paper proposed a multi-time scale power system production simulation method. It was composed of the mid-long term and short term production simulation. The former aimed to manage uneven seasonal distribution of clean energy. By considering the complementation among wind, solar and hydro energy, it could work out the maintenance schedule of conventional generation and hydro energy allocation scheme. Based on these results, the latter focused on the stochastic characteristics of renewable energy. It could obtain the absorption zone of renewable energy along with the operation schedule and quantitatively evaluate the renewable energy accommodation capacity of the power grid. The case studies based on a provincial power grid in northwest China have proved the correctness and effectiveness of the proposed framework and method. It can provide an overall reflection and method to manage the seasonal distribution and short term stochastic characteristics of renewable energy. The cooperation of multiple energy resources under different time scales can further optimize the power system operation.