Research on Grid-Connected Harmonic Current Suppression Method for Distributed Photovoltaic Power Grid
Distributed photovoltaic grid-connected control for power grids is poor,which seriously affects the operational safety of photovoltaic power grid.For this reason,a distributed photovoltaic power grid grid-connected harmonic current suppression method is proposed.A mathematical model of distributed photovoltaic power grid grid-connected inverter is constructed,and the model is used to obtain the voltage and current data when harmonics exist in the distribution grid and establish a data set.The dataset is divided into test set and training set and then input into the radial basis function(RBF)neural network within the data-driven algorithm.The harmonic source model based on the data-driven algorithm is constructed by iterating the RBF neural network.The model is utilized to obtain the photovoltaic power grid grid-connected harmonic sources.Using the photovoltaic power grid grid-connected harmonic source as input,a harmonic disturbance compensator and a vector proportional integral tracking controller are used to realize distributed photovoltaic power grid grid-connected harmonic current suppression.The experimental results show that the method can quickly and accurately track the harmonics of power grid appearing during grid-connection.The method can effectively suppress the harmonic current distortion.