A three-phase four-leg inverter-based shunt active power filter (APF) is proposed to compensate three-phase unbalanced currents under unbalanced load conditions in grid-connected operation in this study. Since a DC-link capacitor is required on the DC side of the APF to release or absorb the instantaneous apparent power, the regulation control of the DC-link voltage of the APF is important espe...

Nonlinear and unbalanced loads introduce distortions to the power network in form of harmonics asymmetric load conditions. Through rising penetration residential renewable plants, energy is fed back into grid. By shaping output those converters can be mitigated. The technique shunt active filtering allows instantaneous compensation a dedicated nonlinear load, by measuring its distorted consumpt...

In this paper an inverter is taken as a member of Variable Structure System (VSS). A new Park vector based variable structure control (VSC) method is proposed. A modified definition of the Park vector is introduced to handle the effect of zero phasesequence component caused by an asymmetrical load. The design of a sliding mode controller consists of two main steps. Firstly, the design of the sl...

Inverter voltage control is an important task in the operation of a DC/AC microgrid system. To improve the inverter voltage control dynamics, traditional approaches attempt to measure and feedforward the load current, which, however, needs remote measurement with communications in a microgrid system with distributed loads. In this paper, a load current observer (LCO) based control strategy, whi...

Due to the wide spread of power electronics equipment in modern electrical systems, the increase of the harmonics disturbance in the ac mains currents has became a major concern due to the adverse effects on all equipment. Power electronic converters are commonly used for interfacing distributed generation (DG) systems to the electrical power network. However, the unbalanced voltage compensatio...

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in...

This paper presents a new control method for a three-phase four-wire Unified Power Quality Conditioner (UPQC) to deal with the problems of power quality under distortional and unbalanced load conditions. The proposed control approach is the combination of instantaneous power theory and Synchronous Reference Frame (SRF) theory which is optimized by using a self-tuning filter (STF) and without us...

This paper describes the mathematical modelling of selfexcited induction generators (SEIGs) with are improved electronic load controller (IELC) for microhydel applications supplying variety of loads. In small hydro plants, governor unit of turbine can be eliminated using IELC, which is simple and cost effective. The improved electronic load controller is a combination of a three-phase insulated...

estimate of sediment load is required in a wide spectrum of water resources engineering problems. the nonlinear nature of suspended sediment load series necessitates the utilization of nonlinear methods to simulate the suspended sediment load. in this study artificial neural networks (anns) are employed to estimate daily suspended sediment load. two different ann algorithms, multi layer percept...