A distribution network power flow calculation method and system considering distributed photovoltaic

Abstract

The invention discloses a distribution network power flow calculation method and system considering distributed photovoltaics, including: calculating the maximum output of photovoltaic power generation according to the inverter control mode; setting the initial value required for node S power flow calculation, and performing The power flow calculation of the AC part of the distribution network obtains the node S data; the obtained node S data is transmitted to the DC part of the inverter, and the power flow calculation of the DC part of the inverter is carried out forward and backward, and the DC system is obtained and passed to the node The active power and reactive power of S; determine whether the active power and reactive power are converged; optimize the grid-connected position of distributed photovoltaics according to the final power flow calculation results, and perform power flow distribution on the distribution network. The invention not only perfects the distribution network power flow model for distributed photovoltaic grid-connected, improves the calculation accuracy, but also greatly shortens the power flow calculation time, realizes the rapidity of calculation, and improves the ability to change the variable distributed photovoltaic output. Coping ability.

Description

technical field [0001] The invention relates to the technical field of electric power automation, in particular to a distribution network power flow calculation method and system considering distributed photovoltaics. Background technique [0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art. [0003] Distributed photovoltaics are an important form of renewable energy utilization. With the massive access of distributed photovoltaics in distribution networks, power flow calculations have undergone new changes. Although the power flow calculations of pure AC power grids and AC-DC hybrid power grids are relatively mature, the power flow calculations of distribution networks considering distributed photovoltaics have not reached the same level. How to effectively simulate photovoltaic grid-connection for power flow calculation of distribution network is still a problem worthy of...

AI Technical Summary

Problems solved by technology

[0006] (1) According to the different control methods of the inverter, the DC part of the inverter is equivalent to several types of AC power flow nodes, so that the DC part is equivalent to the AC part. Although this type of power flow calculation method improves the calculation speed, it weakens the It is difficult to iterate the power flow, but it is obviously not accurate enough, and it cannot clearly reflect the changes on the photovoltaic DC side

[0007] (2) Establish the power flow calculation model of the cow-pull method for the AC part and the DC part of the distribution network, including the basic equation of the converter, the DC network equation, the two control equations corresponding to the converter, and the AC network equation. The augmented Jacobian matrix is ​​formed partly, and the AC part and the DC part are solved iteratively in a unified way. It can be seen that the mathematical model of power flow calculation is relatively complicated and inevitably lacks efficiency.

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