Power distribution network flow computing method based on equivalent node injecting current transformation

Abstract

The invention discloses a power distribution network flow computing method based on equivalent node injecting current transformation. The method comprises the steps that firstly based on a traditional fundamental principle of a Newton-Raphson method, the equivalent node injecting current transformation is adopted, a non-linear flow equation which corresponds to PG nodes in a power distribution network is transformed into a linear equation, accordingly a Jacobian matrix in a flow iteration calculation formula can be simplified, most elements of the matrix are enabled to be constants, repeated calculation is not needed, and calculated amount is reduced; then the Jacobian matrix is calculated through a sparse technology, memory space is greatly saved, and calculation speed and efficiency of an algorithm are improved; finally, accuracy and effectiveness of the algorithm can be verified through test cases. In addition, through compassion of calculation performance of different algorithms, the computing method has the advantages of being high in calculation speed, high in calculation efficiency, good in convergence property and strong in looped network processing capacity.

Description

technical field [0001] The invention belongs to the field of power system analysis and calculation, and in particular relates to a distribution network power flow calculation method based on equivalent node injection current conversion. Background technique [0002] Distribution network power flow calculation is an important content of distribution system analysis, and it is an important basis for quantitative analysis of the rationality, reliability and economy of distribution network planning, design and operation mode. The distribution network is significantly different from the transmission network in terms of network structure and operating characteristics. The distribution network has the characteristics of high R / X ratio, many branches, and a radial network structure. The distribution network is an open loop when it is in normal operation. Power is running. Therefore, it is very important to study the power flow algorithm suitable for distribution network characteri...

AI Technical Summary

Problems solved by technology

[0003] In recent years, scholars at home and abroad have proposed a variety of power flow algorithms according to the characteristics of distribution networks, such as fast decoupling method, forward-backward generation method, loop impedance method, improved Newton method and implicit Zbus Gaussian method, etc.; among them, fast decoupling method The convergence of the method in the distribution network is poor; the calculation efficiency of the forward push-back method in the radial distribution network is high, but the ability to deal with multiple loops is poor; the ability of the loop impedance method to deal with the ring network has been enhanced , but the ability to deal with PV nodes is weak; the non-zero elements of the Jacobian matrix in the traditional Newton-Raphson method and the improved Newton method are variable, and each iteration needs to be recalculated, which requires a large amount of calculation and takes a long time. Long and low efficiency; the implicit Zbus Gauss method and Ybus method need to give the initial value of the equivalent injection current of the node, and use the linear power flow equation to iterate repeatedly until convergence. The algorithm has a first-order convergence speed and can solve multi-loop power distribution network, but the ability to handle multiple power sources is weak

Images