The way engineers use fuzzy control in real world applications is often not coherent with an understanding of the control rules as logical statements or implications. In most cases fuzzy control can be seen as an interpolation of a partially speciied control function in a vague environment, which reeects the indistinguishability of measurements or control values. In this paper we show that equa...

The transformerless PV inverters are the major functional units of modern grid-connected PV energy production systems. In this paper, a new optimization technique is presented for the calculation of the optimal types and values of the components comprising a transformerless PV inverter, such that the PV inverter Levelized Cost Of the generated Electricity (LCOE) is minimized. The proposed metho...

This paper proposes a single-phase five-level photovoltaic (PV) inverter topology for grid-connected PV systems with a novel pulse width-modulated (PWM) control scheme. Two reference signals identical to each other with an offset equivalent to the amplitude of the triangular carrier signal were used to generate PWM signals for the switches. A digital proportional–integral current control algori...

This paper presents a single phase five level photovoltaic (PV) inverter topology for grid connected PV systems with a novel Pulse Width Modulated (PWM) control scheme. Two reference signals identical to each other with an offset equivalent to the amplitude of the triangular carrier signal were used to generate PWM signals for the switches. A digital Proportional-Integral derivative (PID) curre...

In this paper, modeling, simulation and experimental study of a 10 kW three-phase grid connected inverter are presented. The mathematical model of the system is derived, and characteristic curves of the system are obtained in MATLAB with m-file for various switching frequencies, dc-link voltages and filter inductance values. The curves are used for parameter selection of three-phase grid connec...

The distributed generation (DG) systems based on the renewable energy sources have rapidly developed in recent years. These DG systems are powered by micro sources such as fuel cells, photovoltaic (PV) systems, and batteries. The micro grid concept consists of two stages, in the first stage the low level voltage from the pv cell is converted to high level voltage by using DC-DC converter. In th...

In this paper, we propose tunable optical interleaver filters based on the combined Michelson interferometer (MI) and the Gires-Tournois interferometer (GTI) with polarization diversity. The tuning capability is achieved by integrating liquid crystals into the interleaver. In addition to the tunability, it is also shown that the response for this proposed interleaver has a flat-top. Various GTI...

We are investigating the radar as a non-destructive technique to detect early-stage flaws and reinforcement in concrete structures. In this paper, we simulate the groundpenetrating radar (GPR) assessment of concrete structures using three-dimensional (3D) finite-difference time-domain (FDTD). The discussion focuses on the evaluation of the performance of GPR in assessing dispersive and heteroge...

In Korea, an accelerator-driven system (ADS) called HYPER (Hybrid Power Extraction Reactor) is being studied for the transmutation of the radioactive wastes. HYPER is a 1 000 MWth leadbismuth eutectic (LBE)-cooled ADS. In this paper, the neutronic design characteristics of HYPER are described and its transmutation performances are assessed for an equilibrium cycle. The core is loaded with a duc...

Bow-tie diagrams are emerging as a very useful tool to depict and maintain an up-to-date, real-time, working risk management system embedded in daily operations. They are a proven concept in the worldwide offshore industry. These diagrams provide a pictorial representation of the risk assessment process. This article introduces the bow-tie concept to the downstream and chemical process industri...