Reactive power optimization method and device for transmission and distribution network

Abstract

The invention discloses a reactive power optimization method and device for a transmission and distribution network. The method comprises the following steps: constructing a transmission and distribution network two-stage robust reactive power optimization model considering uncertainty, and aiming at the structural characteristics of the constructed model, providing a step and a process for decomposing the model into a main problem and a sub-problem by adopting a benders decomposition method and solving the main problem and the sub-problem. According to the invention, uncertainty of new energypower generation and load prediction is effectively considered, the anti-disturbance capability of the reactive power optimization decision result is enhanced, various reactive power compensation andreactive power support elements of the power transmission and distribution network are systematically and comprehensively considered in the method, and meanwhile, the model and the solving method provided by the invention not only can ensure that the obtained result is an optimal solution, but also have relatively high calculation efficiency.

Description

technical field [0001] The present application relates to the technical field of power transmission and distribution control in power grids, and in particular to a reactive power optimization method and device for power transmission and distribution networks. Background technique [0002] Under the traditional power grid structure, power generation, power transmission, power distribution, and power consumption have a clear and clear hierarchical structure. With a large number of distributed power sources connected to the distribution network, the operating conditions of the distribution network are becoming more and more complex. To a certain extent, it is possible to change its own operation. However, it is prone to new problems such as voltage over-limit and large output power fluctuations. At the same time, the reactive power and voltage adjustment methods of the distribution network are more abundant, and the reactive power and voltage of each level of the transmission a...

AI Technical Summary

Problems solved by technology

And because the proportion of new energy power generation in the current power grid continues to increase, and new energy power generation is easily affected by the external environment, making its output more uncertain, so it is necessary to take into account the output of new energy power generation in the reactive power optimization problem. Uncertainty, such as wind power, etc.

In addition, since it is difficult to accurately predict reactive load, it is also necessary to consider the uncertainty of load, so as to enhance the reactive power and voltage operation scheme to cope with the uncertainty of new energy power generation output and load forecast

[0003] At present, there are the following shortcomings in the existing technical solutions: the existing method of only optimizing the reactive power voltage of the transmission network or distribution network cannot make full use of the respective adjustment capabilities of the transmission and distribution network, so only the overall planning of the transmission and distribution network Analysis and decision-making, to improve the ability to optimize the allocation of reactive power resources at a deep level, can realize the maximum utilization of control means

In addition, the current layered automatic voltage control optimizes the reactive power of the transmission and distribution network by setting the gateway power or voltage amplitude, which has not fully realized the two-way interaction between different voltage levels of the distribution network. no longer applicable

[0004] On the other hand, most of the current reactive power optimization methods considering uncertainty are only applicable to the distribution network and cannot be applied to the transmission network. The reactive power optimization problem of the distribution network is mainly due to the fact that the linear power flow equation of the transmission network cannot take reactive power and voltage into account

And in terms of the construction and solution of the active and reactive power joint optimization model of the transmission and distribution network, since the traditional active power optimization and reactive power optimization are usually carried out separately, there are relatively few studies on the active and reactive power joint optimization.

Moreover, since the joint optimization model of active and reactive power is usually a mixed integer nonlinear programming problem that includes both discrete variables and continuous variables, that is, it is an NP-hard problem, and it is very difficult to solve such problems on a large scale. Specialized in order to efficiently solve for it

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