The traditional interval power flow studies have ignored some actual physical constraints

such as output limit constraints of balancing machine

steady-state adjustments of generation

which therefore bring about conservative results. Interval DC power flow models with the consideration of the balancing machine constraints and steady-state adjustments are set up respectively. Furthermore

these problems are solved by optimization method. Moreover

the proposed method could be extended to other interval DC power flow problems including different constraints. Finally

the simulations of 9-bus and IEEE 118-bus system verify the effectiveness of the proposed method and the conservativeness of the traditional interval DC power flow model is reduced.