GRID-CONNECTED PV-SYSTEMS AND HARMONICS

摘要

Analysing the harmonics in a LV- and MV-grid consisting not linear loads and grid-connected PV-systems is difficult due to the interaction between the different components. Furthermore the characteristics of the most components depend from frequency. In practice many loads and multiple PV-inverters are connected to the grid. A simple though accurate method is developed to estimate the pollution of the electricity network with harmonics in case a large number of inverters is connected to the grid. The method is called the 'Complex Conductance Measurement Method'. Although this method is written for inverters of small grid connected micro generators, it can also be applied for all kinds of loads. To make an estimation of a possible harmonic problem, the modelling and characteristics of the grid, loads and inverters, with respect to harmonics, are described in this paper.