Power distribution network overvoltage suppression method and system based on active power limit value algorithm

Abstract

The invention relates to a power distribution network overvoltage suppression method and system based on an active power limit value algorithm. The method comprises the steps as follows: when the voltage value of a key busbar of a photovoltaic system of a power distribution network exceeds a power distribution network overvoltage alarm value, active power limit values of the key busbar and commonbusbars are determined according to the overvoltage alarm moment of the power distribution network as well as active output values and voltage values of the key busbar and the common busbars of the photovoltaic power generation system of the power distribution network at the current moment, the power extraction capacity of each busbar in the photovoltaic power generation system is determined according to the active power limit value of the key busbar and the active power limit values of common busbars, and suppression of overvoltage of the power distribution network is realized according to the power extraction capacity of each busbar. According to the technical scheme, active output of the photovoltaic system is limited and regulated, the occurrence rate that the voltage is out of limit is effectively suppressed, the problem of high costs of the prior art is solved, and overvoltage suppression of the power distribution network is realized precisely on the premise of simple configuration.

Description

technical field [0001] The invention relates to the field of photovoltaic power generation control, in particular to a distribution network overvoltage suppression method and system based on an active power limit algorithm. Background technique [0002] In recent years, the installed capacity of global photovoltaic power generation systems has increased year by year. The International Energy Organization predicts that by 2050, the electricity provided by photovoltaics will account for 11% of the world's electricity. The penetration rate of photovoltaics and other distributed power sources is gradually increasing. A great technical challenge has come, and the voltage limit problem is one of them; the overvoltage of the distribution network is not only a simple power quality problem, the stable level of the voltage directly determines the stability of the power system and the availability of the photovoltaic system. degree. [0003] At present, there have been a large number ...

AI Technical Summary

Problems solved by technology

[0003] At present, there have been a large number of research results at home and abroad on the voltage limit problem caused by the high penetration rate of photovoltaics. The most direct solution includes adjusting the position of the transformer tap or replacing the transformer to transform the distribution network, but adjusting the tap The effect is limited due to the influence of operation and maintenance factors, and the cost of replacing the transformer is too high; because the resistance inductance in the distribution network is relatively large, and the voltage level is greatly affected by the active power flow, the more widely studied methods can be summarized into four types: configuration The energy storage system suitable for photovoltaics adopts the active power droop control strategy, the reasonable power flow calculation based on sensitivity calculation and the active power control method based on the equivalent circuit; among them, the configuration of energy storage is the most effective but the cost of the energy storage unit is often large, and the active power The droop control strategy is the simplest but it is difficult to guarantee the fairness of the active power reduction of all users in the system. The calculation method based on sensitivity needs to know the global parameters of the system as the premise, and the operation is complicated. The active power control method based on the equivalent circuit is affected by the accuracy of the equivalent circuit. the limitations of

Images