Current harmonic index quantification assessment method of grid-connected photovoltaic power generation system

Abstract

The invention relates to the field of grid-connected photovoltaic power generation performance testing, in particular to a current harmonic index quantification assessment method of a grid-connected photovoltaic power generation system. The current harmonic index quantification assessment method is characterized by including the following steps: (1) performing interval statistics on irradiation intensity; (2) performing statistic analyzing on the timed sampling daytime actually measured irradiation intensity according to the intervals; (3) performing sampling and recording on voltage and amperage of the photovoltaic power generation system on the grid-connection points of the photovoltaic power generation system; (4) determining the measured current harmonic weight coefficients corresponding to the different irradiation intensity; (5) obtaining the harmonic current average value under different irradiation conditions; and (6) calculating the weighting current harmonic value according to the current harmonic weight coefficients of the irradiation intensity intervals. By means of the current harmonics index quantification assessment method, under the condition that the current harmonics of the grid-connected photovoltaic power generation system accord with the standard limiting value requirements, the comprehensive current harmonics of the grid-connected photovoltaic power generation system are obtained in weighting mode when the irradiation intensity changes, and accordingly assessment on performance of the photovoltaic power generation system can be achieved.

Description

technical field [0001] The invention relates to the field of photovoltaic power generation grid-connected performance testing, in particular to a method for quantifying and evaluating the current harmonic index of a photovoltaic grid-connected power generation system. Background technique [0002] In recent years, new energy represented by wind energy and solar energy has developed rapidly around the world. By the end of 2011, the cumulative installed capacity of solar power generation in the world reached 67.4 million kilowatts. Among them, the growth rate of photovoltaic module output is astonishing. In 2010, the shipment of solar cell modules reached 20GW, and in 2011, the shipment of photovoltaic modules reached 27.7GW. It is estimated that by 2020, the annual output of photovoltaic modules will reach 40GW. When a large number of photovoltaic power generation systems are integrated into the grid, power quality problems are inevitable. Photovoltaic grid connection under...

AI Technical Summary

Problems solved by technology

However, due to the influence of special factors such as radiation changes when photovoltaic power generation is connected to the grid, traditional detection and analysis methods can only judge whether the grid-connected photovoltaic system meets the standard limit, and it is difficult to judge whether the grid-connected photovoltaic system meets the standard requirements. Judgment and improvement of photovoltaic performance

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