Calculation Method of Interval Power Flow Based on Cartesian Coordinate Form of Linear Programming

Abstract

The invention discloses a rectangular coordinate form interval power flow calculation method based on linear programming. The method comprises the following steps of 1, establishing a rectangular coordinate form power flow equation, calculating an interval midpoint power flow solution, supposing an active power and a reactive power of a wind turbine generator set can be represented by intervals, establishing a power flow equation in a rectangular coordinate form, performing power flow calculation on the interval midpoint value, and obtaining a power flow solution; 2, estimating a fluctuation interval in which the power flow exists; 3, establishing a rectangular coordinate affine coordinate form of voltage; 4, calculating an affine coordinate form of the node power, introducing a voltage affine coordinate form into the rectangular coordinate trend equation, and obtaining an affine coordinate form of node power; and 5, compressing a power flow solution interval by means of linear programming. A linear program is constructed for respectively minimizing and maximizing a noise element, thereby obtaining a voltage real part and an imaginary part with shortest interval length.

Description

technical field [0001] The present invention relates to the technology for solving power system interval power flow calculations, in particular to a method for calculating interval power flow in rectangular coordinates based on linear programming. When solving interval power flow equations, the method expresses voltage phasors in the form of rectangular coordinates, and Affine arithmetic is used to transform the problem of interval power flow equation in Cartesian coordinates into the solution of linear programming problem, and the upper and lower boundaries of the interval power flow solution are obtained by solving linear programming. Background technique [0002] After the new energy units are integrated into the power grid, the uncertainty of their output makes the voltage fluctuate frequently, which poses a threat to the safe operation of the power grid. In order to analyze the influence of new energy output on the grid power flow (mainly grid voltage), the traditional ...

AI Technical Summary

Problems solved by technology

With the continuous development of modern power systems, the continuous expansion of the grid scale, and the access of more and more new energy sources, the traditional Monte Carlo method will greatly increase the number of samples, the scale of power flow calculations will also increase, and the calculation time Rapid growth, no longer suitable for analyzing the impact of new energy output on grid voltage

Therefore, new analysis methods need to be explored. Interval power flow analysis provides a new idea to solve this problem, but the estimated interval range is too conservative and the convergence is not guaranteed. The interval power flow method based on linear programming and affine arithmetic is very difficult. This problem can be solved well, but the power flow method in polar coordinates has interval calculations in non-affine forms such as trigonometric functions, which affects the estimation accuracy of intervals

Images