Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for obtaining a model of an electrical power system including multiple subcircuits. Assigning each of multiple subcircuits to a processing core from among multiple processing cores employed for simulation of the model; executing a simulation of electric grid behaviors of the model, where the simulation of each subcircuit can be executed by the respective processing core assigned to the subcircuit. Sending a message, from a first processing core assigned to a first subcircuit to a second processing core assigned to a second subcircuit, the message including one or more boundary conditions at an interface between the first subcircuit and the second subcircuit in the model.

Abstract: Methods, systems, and apparatus, including medium-encoded computer program products, for selecting, from a unified electrical power grid model, a first proper subset of elements of the model. A first electrical grid simulation model is selected. A second, differing proper subset of elements of the model are selected. A second electrical grid simulation model that differs from the first electrical grid simulation model is selected. A set of boundary conditions common to the first electrical grid simulation model and the second electrical grid simulation model are determined. Operation of the electrical power grid is simulated, and can include (i) simulating, using the first electrical grid simulation model, the first proper subset of elements of the unified model, and the set of boundary conditions; and (ii) simulating, using the second electrical grid simulation model and the second proper subset of elements of the unified model, and the set of boundary conditions.