New current control method for grid-connected inverter of domestic power plant

Abstract

Several non-linear loads are connected to the low voltage public grid, for example: compact fluorescent lamps (CFL) or electronic devices contain switched mode power supplies (SMPS) and diode rectifiers. These distort the grid with current harmonics therefore the grid voltage waveform become distorted. We worked out a new current control strategy for grid-connected inverters of domestic power plants. The root mean square (RMS) value and the fundamental of the generated AC current can be increased and the harmonic content of the network can be reduced with the new method, that we call reversed strategy. We compared it with the commonly used sinusoidal current control method. An analytical comprehension of the two strategies is discussed in this paper. By comparing their consumed RMS and fundamental currents we defined coefficients (k RMS_rev_sin and k fund_rev_sin ), which depend only on the total harmonic distortion of the network voltage (THD U )