Abstract:Power flow calculation is the basis of energy management in integrated energy system. The existing power flow calculation model of the integrated energy adopts the combination of the power network node model and the heat network loop model. In the process of real-time power flow calculation, the heat network loop should be searched to form multiple independent minimum heat loops after network topology analysis forms nodes. Based on the minimum loop model, the Newton method is used to calculate the power flow; In order to facilitate the combination with the node model of power flow and improve the algorithm efficiency and convergence performance of integrated energy flow calculation, we use the unit value model of heat network node model: take the water supply temperature, return water temperature, supply pressure and return water pressure of the heat network as the state quantity of the network, and take the net injection flow of the return water and supply node as the zero, and the injection energy of the return water and supply node as the basic model, In this paper, BFS(Broyden Fietcher Shanmo) algorithm is used to solve the nonlinear equations of heat power flow. The Jacobian matrix is only calculated once and inversed. The power flow calculation is realized by recursion, which overcomes the shortcomings of Newton''s method that needs multiple derivation and inversions, avoids searching the minimum loop of real-time network, is convenient to solve jointly with the node model of power network, and is more suitable for the power flow calculation in large-scale heat electric power combined system..