A storage method for power system power system Cartesian coordinates pq decomposition method based on sparse technology

Abstract

The invention provides an electric power system rectangular coordinate PQ decomposition method tidal data storage method based on sparse technology. According to the method of the invention, non-zero elements at upper and lower corners of three arrays of Y(n,2n), B'(n-1,n-1) and B''(n-1,n-1) in a traditional method are stored in an A(n,d) array, thereby greatly reducing number of storage units, improving data file reading and writing speed, and improving calculation speed of Ipi, Iqi or deltaPi and deltaQi in a PQ decomposition method trend. Furthermore the number of storage units is furthermore reduced by means a fact that the positions of non-zero elements in the arrays of the three arrays of Y(n,2n), B'(n-1,n-1) and B''(n-1,n-1). Compared with methods such as linked list method, the number of storage units is greatly reduced. Compared with the traditional method such as an IEEE-118 node system, the number of maximal storage units and the number of actual storage units of the electric power system rectangular coordinate PQ decomposition method tidal data storage method are respectively 10.00% and 4.48% of the number of maximal storage units and the number of actual storage units of the IEEE-118 node system, and data writing time and data reading time of the actual storage units of the electric power system rectangular coordinate PQ decomposition method tidal data storage method are respectively 11.45% and 6.20% of data writing time and data reading time of the IEEE-118 node system. Along with node number increase, the advantages of the electric power system rectangular coordinate PQ decomposition method tidal data storage method become more remarkable.

Description

technical field [0001] The invention belongs to the field of power system analysis and calculation. Background technique [0002] Newton-Raphson method (Newton method) is the most commonly used method in power system power flow calculation. According to the calculation process, it can be divided into rectangular coordinate Newton method and polar coordinate Newton method. According to the simplification of the two characteristics, the polar coordinate PQ can be derived respectively. Decomposition method and Cartesian coordinate PQ decomposition method. Generally speaking, the rectangular coordinate Newton method is better understood than the polar coordinate Newton method in terms of principle explanation and calculation programming, but from the perspective of the calculation process, the polar coordinate Newton method has fewer equations than the rectangular coordinate Newton method. The Jacobian matrix The types and quantities of elements are also small, and sometimes th...

AI Technical Summary

Problems solved by technology

However, if the B′ and B″ array elements completely use the imaginary part of the Y array element, or if only the B′ and B″ array elements are the same but different from the imaginary part of the Y array element, it may affect the iteration of the power flow of the PQ decomposition method times or convergence

[0007] (2) The storage method of Y, B', B" array elements is unreasonable

This storage method will cause a great waste of storage space and take too long to read and write data files and calculation time, and use Y(n, 2n) array to calculate I pi , I qi or ΔP i , ΔQ i extremely inefficient

If you use coordinate storage, sequential storage, linked list storage, etc., although you can save a lot of storage units, the data reading process is cumbersome because the diagonal elements and non-diagonal elements are stored separately, which is not conducive to its calculation. and processing, calculating I pi , I qi or ΔP i , ΔQ i time efficiency is not high

[0009] (3) Y, B', B" array data files have a large number of storage, and the reading and writing time is long

The more data files are stored, the longer it takes to write data files, which also leads to more data files to be opened and longer time to read data files in the PQ decomposition method power flow calculation program, which is not conducive to PQ decomposition real-time computing

[0011] (4) The relationship between the non-zero element positions of Y, B', B" arrays is not fully utilized

In the traditional method, these two characteristics are not used, which leads to the waste of storage units and some unnecessary calculations in the process of factor table formation.

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