A new SOGI-PLL method based on fuzzy logic for grid connected PV inverter

Abstract

<p>Phase angle detection of the grid voltage is an imperative part of control in most applications, especially for the synchronization of the current injected by the grid-connected photovoltaic inverters. Consequently, fast and accurate detection of the phase angle, frequency and amplitude of the grid voltage are indispensable data to ensure a correct generation of reference signals and operation of the grid connected inverters. We present in this work a new phase-locked loop (PLL) method for single-phase systems. The novelty is to generate an orthogonal voltage system using a second-order generalized integrator (SOGI), followed by a Park transformation, whose quadrature component is forced to zero by the fuzzy logic, in order to obtain rapid detection and a more accurate picture of the phase angle. Furthermore, simulation results with PSIM software will be submitted to verify the performance and effectiveness of the proposed method strategy. Finally, the experimental test will be used to extract the result and discuss the validity of the proposed algorithm.</p><p> </p>

Recent advances in phase-locked loop based synchronization methods for inverter-based renewable energy sources

“…They can be classified into two categories, the open-loop and closed-loop approaches as depicted in Figure 1. The zero-crossing detection method [6][7][8], adaptive notch filtering [9,10], artificial intelligence [11,12], nonlinear least square [13], discrete Fourier transform [14], delayed signal cancellation [15,16], and Kalman filter [17] are the common examples of the open-loop category. On the other hand, the PLL method, SRF-PLL [18,19], EPLL [20], and SOGI-PLL [21]…”

A fuzzy rule based approach for islanding detection in grid connected inverter systems

“…Moreover, when several inverters are connected in parallel to the same node, it is easy to install, inexpensive and always efficient [16]. On the other hand, if the system is connected to a weak grid where the distributed generation source is of some importance, this method will result in a slight decrease in the quality of the waveform of the inverter output current and may cause undesirable instability with respect to the main grid energy [1]. Therefore, this method remains a good compromise between waveform quality, efficiency of islanding detection and the effect on the transient response of the system.…”

“…This is called islanding and can be voluntary or involuntary. Indeed, during grid maintenance, grid outages can lead to generator islands [1], [2]. Since the loss of the network is voluntary, the island is well known and can be closed by the staff member concerned [3], [4].…”

SOGI-PLL Aprimorado por Algoritmo de Fourier de um Ciclo

“…Uma pesquisa sobre diferentes métodos de PLLs mostrou que para uma ampla gama de condições de perturbação da rede, o SOGI-PLL apresentou desempenho satisfatório para alcançar uma compensação entre precisão de estado estacionário e resposta dinâmica [24]. Em [25] é mostrado um novo método de PLL para sistemas monofásicos, que gera um sistema de tensão ortogonal usando um integrador generalizado de segunda ordem (SOGI), seguido por uma transformada de Park, cujo componente em quadratura é forçado a zero pela lógica fuzzy, a fim de obter uma detecção e uma imagem mais precisa do ângulo de fase. Um dispositivo de supressão de arco flexível monofásico (SFASD) baseado em controle de retrocesso e integrador generalizado de segunda ordem (BSC-SOGI-PLL) é apresentado em [26].…”