节点导纳矩阵元素存贮的新方法

A new method for storing the data of bus admittance matrices

针对电力系统节点导纳矩阵传统存贮方法占用内存空间较多、存取速度较慢等问题,提出了一种存贮电力系统节点导纳矩阵Y元素的新方法。该方法利用了电力系统网络结构以及Y阵元素的特点,存贮Y阵对角元素的行下标及所连接的支路数、上三角中非零的非对角元素的列下标及其相应的参数。因此能大大节省存贮单元,且使得存贮方式极为简单、直观、便于检索和计算,从而大大提高Y阵数据文件的读写速度。以IEEE-118系统为例,新方法与不考虑稀疏性的传统方法及考虑稀疏性的链表法相比,前者所需的最大存贮单元分别为后者的9.32%和55%,而实际存贮单元还可进一步减少。新方法写入或读取数据文件的时间分别为不考虑稀疏性传统方法的15.34%和12.49%,且节点数越多,优势越明显。

According to the problems that the conventional algorithm occupied too much storage and accessed so slow,a new method for storing the elements of a bus admittance matrix Y in power systems was presented in the paper.The new method has taken the advantage of the structure of power system network and the characteristic of the elements in matrix Y to store the row suffixes for the diagonal elements and the branch numbers connected to other buses,as well as the column suffixes of nonzero off-diagonal elements in the upper triangle and the corresponding parameter values.Which made the storage units of the new method being largely saved,and the data storage mode being simpler,more visualized,and the searching and calculating of the data become easier.Also made the data access speed of matrix Y has been greatly increased.Taking IEEE-118 bus system as calculating example,with the conventional storage method without considering the sparsity in matrix Y and the chain method considering the sparsity in matrix Y,the storage units of date files in the new method were only 9.32% to the former and 55% to the latter.But the actual storage units in the new method can be decreased further.In addition,the time for reading and wring the date file in the new method were just 15.34% and 12.49% to the conventional algorithm without considering the sparsity.And the more the nodes in the system there were,the more obvious the advantages are.