Secondary regulation control method of DC microgrid based on line loss optimization

Abstract

The invention belongs to the interdisciplinary field of a power distribution network technology and an electric power and electronics technology, and especially relates to a DC micro network secondary adjusting control method based on line loss optimization. First of all, a DC micro network system is constructed, an upper-layer control center, according to sampling information of each converter, calculates the line loss power of the DC micro network system; then a controllable voltage source sagging control intercept common mode and a differential mode adjusting amount are calculated; and output voltage of each controllable power supply in a DC micro network is adjusted through sagging control parameters such that the output of each power supply is controlled, the trend on each distribution branch is adjusted accordingly, and the line loss is reduced. According to the invention, the line loss of the DC micro network is optimized under the condition that line impedance and enormous operation information are measured without reliance on high-sensitivity sensors. Experiment results indicate that compared to a conventional DC micro network control method, the control method provided by the invention can effectively reduce the line loss, and the specific reduction amplitude is determined according to the distribution condition of the line impedance and loads.

Description

technical field [0001] The invention belongs to the intersecting field of distribution network technology and power electronics technology, and in particular relates to a DC micro-grid secondary regulation control method based on line loss optimization. Background technique [0002] Different from the single power source and tree structure of the traditional distribution network system, there are multiple DC voltage sources in the DC microgrid. This makes it possible to optimize line losses by controlling power flow in distribution networks. The DC microgrid system has only gradually emerged in recent years, and there are still few methods to optimize the control of its line loss. In the AC microgrid, some studies have achieved line loss optimization by measuring the line impedance and transmission power step by step, but this method is too dependent on the accuracy of the sensor, which is difficult to achieve in practice, and even counterproductive. [0003] For the opera...

AI Technical Summary

Problems solved by technology

However, the method in formula (2) forces the output of the two power supplies to be the same, which will inevitably increase the line loss

[0009] In the control of some AC power grids, there are some methods to optimize the line loss by controlling the power flow, but these methods need to measure the line impedance through the sensor or make a difference between the adjacent two line losses through the iterative method of line loss. These methods rely too much on The accuracy of the sensor cannot achieve the theoretical effect in practice

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