There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

This paper reviews the current status and implementation of battery chargers, charging power levels, and infrastructure for plug-in electric vehicles and hybrids. Charger systems are categorized into off-board and on-board types with unidirectional or bidirectional power flow. Unidirectional charging limits hardware requirements and simplifies interconnection issues. Bidirectional charging supports battery energy injection back to the grid. Typical on-board chargers restrict power because of weight, space, and cost constraints. They can be integrated with the electric drive to avoid these problems. The availability of charging infrastructure reduces on-board energy storage requirements and costs. On-board charger systems can be conductive or inductive. An off-board charger can be designed for high charging rates and is less constrained by size and weight. Level 1 (convenience), Level 2 (primary), and Level 3 (fast) power levels are discussed. Future aspects such as roadbed charging are presented. Various power level chargers and infrastructure configurations are presented, compared, and evaluated based on amount of power, charging time and location, cost, equipment, and other factors.

/pdf/review-of-battery-charger-topologies-charging-power-levels-85yy2igx2w.pdf

Review of Battery Charger Topologies, Charging Power Levels, and Infrastructure for Plug-In Electric and Hybrid Vehicles

http://ieeexplore.ieee.org/iel5/5610941/5624686/05624745.pdf

Power electronics

Energy storage systems (ESSs) are enabling technologies for well-established and new applications such as power peak shaving, electric vehicles, integration of renewable energies, etc. This paper presents a review of ESSs for transport and grid applications, covering several aspects as the storage technology, the main applications, and the power converters used to operate some of the energy storage technologies. Special attention is given to the different applications, providing a deep description of the system and addressing the most suitable storage technology. The main objective of this paper is to introduce the subject and to give an updated reference to nonspecialist, academic, and engineers in the field of power electronics.

Energy Storage Systems for Transport and Grid Applications

The issue of renewable energy is becoming significant due to increasing power demand, instability of the rising oil prices and environmental problems. Among the various renewable energy sources, fuel cell is gaining more popularity due to their higher efficiency, cleanliness and cost-effective supply of power demanded by the consumers. This paper presents a comprehensive review of different fuel cell technologies with their working principle, advantages, disadvantages and suitability of applications for residential/grid-connected system, transportation, industries and commercial applications. Development of mathematical model of fuel cell required for simulation study is discussed. This paper also focuses on the necessity of a suitable power-conditioning unit required to interface the fuel cell system with standalone/grid applications.

A review on fuel cell technologies and power electronic interface

In this paper, a new active clamping current-fed half-bridge converter is proposed, which is suitable for fuel cell power generation systems. The proposed converter is superior to conventional dc-dc converters in terms of efficiency and component utilization. The overall efficiency is estimated to be 94% at full load.

Fuel Cell Generation System With a New Active Clamping Current-Fed Half-Bridge Converter

This paper presents a novel design method to reduce cogging torque of interior type permanent magnet (IPM) motor. In the design method, the optimal notches are put on the rotor pole face, which have an effect on variation of permanent magnet (PM) shape or residual flux density of PM. Through the space harmonics field analysis, the positions of notches are found and the optimal shapes of notches are determined by using finite element method (FEM). The validity of the proposed method is confirmed by experiments.

A Novel Cogging Torque Reduction Method for Interior Type Permanent Magnet Motor

This paper deals with the analysis for the irreversible demagnetization characteristics of a ferrite-type permanent magnet in the line-start motor using the two-dimensional finite-element method (2-D FEM). The demagnetizing currents are calculated from the transient analysis in the combination voltage equation with mechanical dynamic equation, and peak currents are applied to the irreversible demagnetization analysis computed by 2-D FEM. The nonlinear characteristic of the magnetic core is considered as well as that of a permanent magnet on the B-H curve in the analysis of irreversible demagnetization.

Analysis of irreversible magnet demagnetization in line-start motors based on the finite-element method

This paper presents a method to calculate motor parameters considering magnetic nonlinearity in interior permanent magnet synchronous motors (IPMSM). To analyze motor characteristics by using equivalent circuits, inductance and iron loss resistance, which are affected critically magnetic saturation, are obtained by using static finite-element analysis. For a fabricated IPMSM, input current and motor characteristics such as torque and efficiency are calculated, and the proposed method is verified by the comparison of calculated and experimental results

Determination of parameters considering magnetic nonlinearity in an interior permanent magnet synchronous motor

This paper propose a fault detection algorithm for stator inter-turn faults (SITFs), dynamic eccentricity faults (DEFs), and hybrid faults (a combination of SITF and DEF) in a permanent magnet (PM) brushless dc motor. We analyzed specific frequency patterns of the stator input current to diagnosis and distinguish the fault types. First, we developed a two-dimensional (2-D) finite element method (FEM) program using a system matrix, and then we confirmed additional specific frequency patterns of the input current by a fast Fourier transform. Finally, specific frequency patterns for each fault type were verified by experimental results.

Jin Hur

Papers

Fuel Cell Generation System With a New Active Clamping Current-Fed Half-Bridge Converter

A Novel Cogging Torque Reduction Method for Interior Type Permanent Magnet Motor

Analysis of irreversible magnet demagnetization in line-start motors based on the finite-element method

Determination of parameters considering magnetic nonlinearity in an interior permanent magnet synchronous motor

Detection of Inter-Turn and Dynamic Eccentricity Faults Using Stator Current Frequency Pattern in IPM-Type BLDC Motors