Reactive power coordinated control algorithm for distributed photovoltaics of distribution network based on eleven-lattice graph

Abstract

The invention relates to a reactive power coordinated control algorithm for distributed photovoltaics of a distribution network based on an eleven-lattice graph. The algorithm comprises the following steps: (1) selecting a reactive power control adjusting method by adopting a selection control strategy of the eleven-lattice graph and using grid-connected point voltage and power factor as synthetic criteria; (2) enabling each adjustable photovoltaic power generation unit to have the same reactive power adjusting margin by adopting an equal proportion method, and distributing each photovoltaic power generation unit within the upper and lower limit range of reactive power according to the principle of identical offset; and (3) enabling each adjustable photovoltaic power generation unit to have the same power factor by adopting an equal power factor method, excluding nonadjustable photovoltaic power generation units and then calculating the total reactive power of a full station target according to a target instruction. The reactive power coordinated control algorithm for the distributed photovoltaics of the distribution network based on the eleven-lattice graph realizes coordinated control of the distributed photovoltaics, and ensures that the distribution network runs under normal and reasonable voltage.

Description

technical field [0001] The invention belongs to a method in the field of reactive power control of electric power systems, and specifically relates to a distributed photovoltaic reactive power coordination control algorithm of a power distribution network based on an eleven-square diagram. Background technique [0002] With the continuous increase in the demand for grid-connected photovoltaic systems in my country, the incentives for various national energy structure adjustments have continued to increase, and the grid-connected photovoltaic capacity in my country has grown rapidly. As of the end of 2014, the cumulative installed capacity of photovoltaic power generation was 28GW, and the newly installed capacity in 2014 was 10.6 million kilowatts, accounting for about 20% of the world's newly installed capacity. The "Twelfth Five-Year Plan for Solar Power Generation Development" pointed out that by the end of 2015, my country's installed solar power generation capacity will...

AI Technical Summary

Problems solved by technology

[0003] However, with the large-scale development of photovoltaic power generation, there will be problems with grid voltage stability

The randomness of photovoltaic power generation may cause the voltage in the grid to fluctuate from time to time, and even cause the line voltage to exceed the limit

In addition, since the inverters at the same grid-connected point have the same influence on the illumination change, the voltage will fluctuate intensified, which may cause frequent actions of the voltage / reactive power adjustment device. When the proportion of photovoltaic power generation in the grid power supply continues to increase, its impact on grid voltage regulation will become more significant, increasing the difficulty of voltage adjustment during normal operation of the grid.

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