The increasing proportion of renewable energy in the new power system brings new challenges to the security and stability of the power system. The random production simulation of the uncertainty of the renewable energy output has guiding significance for the planning and operation of the power system. Firstly, the uncertainty of new energy output and load prediction is modeled. The principal component cluster analysis method is used to process the temporal correlation of new energy output and load data, and the equivalent variable function method is combined to carry out random production simulation. Finally, the correctness of the theoretical method proposed in this paper is verified by an actual power system example in a province, which can provide new ideas and methods for stochastic production simulation of new power systems.