High Efficiency Induction Research Articles

A Loss-Minimization Port-Controlled Hamilton Scheme of Induction Motor for Electric Vehicles

This paper is devoted to the loss model-based controller for an induction motor that propels an electric vehicle (EV). A novel loss calculation method is obtained via the energy balance equation of the induction motor's port-controlled Hamilton model. Since all parameters of the motor are taken into account, the proposed strategy is much more accurate than the conventional loss calculation method. Based on the conceived loss model, a novel loss minimization algorithm is designed. Furthermore, the proposed algorithm is implemented based on the method of interconnection and damping assignment, which offers a high-efficiency induction motor driving solution for EVs. Simulation tests are finally conducted to verify the consistency and the performance of the adopted control scheme.

A high-efficiency induction of dopaminergic cells from human umbilical mesenchymal stem cells for the treatment of hemiparkinsonian rats.

The success rate in previous attempts at transforming human umbilical mesenchymal stem cells (HUMSCs) isolated from Wharton's jelly of the umbilical cord into dopaminergic cells was a mere 12.7%. The present study was therefore initiated to establish a more effective procedure for better yield of dopaminergic cells in such transformation for more effective HUMSC-based therapy for parkinsonism. To examine, in vitro, the effects of enhanced Nurr1 expression in HUMSCs on their differentiation, cells were processed through the three-stage differentiation protocol. The capacity of such cells to synthesize and release dopamine was measured by HPLC. The therapeutic effects of Nurr1-overexppressed HUMSCs were examined in 6-hydroxydopamine-lesioned rats by quantification of rotations in response to amphetamine. Enhanced Nurr1 expression in HUMSCs promoted the transformation into dopaminergic cells in vitro through stepwise culturing in sonic hedgehog, fibroblast growth factor-8, and neuron-conditioned medium. The success rate was about 71%, as determined by immunostaining for tyrosine hydroxylase and around 94 nM dopamine synthesis (intracellular and released into the culture medium), as measured by HPLC. Additionally, transplantation of such cells into the striatum of hemiparkinsonian rats resulted in improvement of their behavioral deficits, as indicated by amphetamine-evoked rotation scores. Viability of the transplanted cells lasted for at least 3 months as verified by positive staining for tyrosine hydroxylase. Nurr1, FGF8, Shh, and NCM can synergistically enhance the differentiation of HUMSCs into dopaminergic cells and may pave the way for HUMSC-based treatments for Parkinson's disease.

Improved efficiency of definitive endoderm induction from human induced pluripotent stem cells in feeder and serum-free culture system.

Improvement of methods to produce endoderm-derived cells from pluripotent stem cells is important to realize high-efficient induction of endodermal tissues such as pancreas and hepatocyte. Difficulties hampering such efforts include the low efficiency of definitive endoderm cell induction and establishing appropriate defined culture conditions to ensure a safe cell source for human transplantation. Based on previous studies, we revised the experimental condition of definitive endoderm induction in feeder- and serum-free culture. Our results suggested that CHIR99021 is more effective than Wnt3A ligand in feeder- and serum-free conditions. In addition, keeping cell density low during endoderm induction is important for the efficiency. On the other hand, we showed that overtreatment with CHIR99021 converted the cells into BRACHYURY-expressing posterior mesoderm cells rather than endoderm, indicating strict CHIR99021 treatment requirements for endoderm differentiation. Nevertheless, these results should enable better control in the production of definitive endoderm-derived cells.

Electrical Machine Topologies: Hottest Topics in the Electrical Machine Research Community

Electrical machines are generating and using most of the electrical energy converted worldwide from fossil fuels or renewable sources. An optimized electrical machine means not only less input energy used but also higher electromechanical energy available as output. This is translated into getting more with less and having an impact on the total amount of greenhouse gases released into the atmosphere, thus mitigating global warming. Benefiting from the latest developments in the electrical machine field are various industries such as electric propulsion [new electric vehicles (EVs) and plug-in hybrid EVs (HEVs)], renewable energy harvesting, consumer applications, and military and aerospace products. This article brings together the contributions from several authors working in academia and industrial research and development centers and comprises a collection of short analyses dedicated to the hottest topics in the electrical machine research community. The article focuses on special and difficult problems to be solved in the design process of the most important electrical machine topologies. The topics discussed cover new machine topologies such as fractional slot winding motors and synchronous reluctance motors; electromagnetic, mechanical, and thermal problems in permanent magnet (PM) machines design; operation of high-speed machines and high-power turbo generators; noise and vibration reduction in switched reluctance motors (SRMs) for automotive applications; high-efficiency induction machines (IMs) configurations compatible with the new international standard and a comprehensive analysis of universal motors (UMs).

Development of a High Efficiency Induction Motor and the Estimation of Energy Conservation Effect

Induction motors are widely used as traction motors on trains. Because energy loss from traction motors accounts for a large portion of energy consumption in commuter trains, highly efficient traction motors are very effective in saving energy. A high efficiency induction motor was therefore developed. Its efficiency was verified through analysis and tests with a prototype machine. This paper presents the calculation results of running simulations for estimating the energy conservation effect of the high efficiency induction motor. The results indicate that the energy consumption is reduced by 6% to 11%.

Design and Efficiency Evaluation of a High-Efficiency Induction Motor for Railway Traction

In commuter trains, a large portion of the energy consumption is caused by losses from traction motors. Therefore, highly efficient traction motors are very effective at saving energy. We developed an induction motor with a high efficiency of 95.5%. This paper presents the design and efficiency evaluation of the prototype machine.

High Efficiency Electric Motors: Economic and Energy Advantages

The energy crisis that is currently being faced by humanity has demanded the revision of the regulations applied to different energy consumers, including electrical machines. The minimum efficiency standards for electrical machines provided by the regulations have been increased. Different categories have been defined to identify the engine based on the level of losses. Regardless of the benefits of ecological nature imposed by recent regulations, the use of the new generations of high efficiency induction engines is attractive from an economic standpoint. The lower power consumption engines and its increasing life span can allow quickly recovering the additional cost of new units and achieving further gains. In this paper the current regulations in different countries of the world are reviewed. According to the energy cost in Argentina, a computation of the times of economic payback is also presented.

Study on Die Construction and Conceptual Design for High-efficiency Induction Motor Prototype

In this paper, concepts for high-efficiency induction motor with sharing core 37kw and below are established and a prototype is constructed. The need for developing high-efficiency induction motor die can be analyzed in terms of electromagnetic design and analyzing technique, mechanical design technology, material technology, and production technique. In order to produce prototypes, motor design, property analysis, and comparison of material cost and efficiency are needed. Methods for such include basic motor design, experiment design, equivalent circuit method, and finite element method. Among these, experiment design can be assessed according to optimal design, main factors, optimal regions, and others. For producing die for constructing prototype, inspection of die development process during die design, understanding of details stage by stage, and optimization of strip layout are essential. When constructing dies, improvement on causes of wear of punch, improvement of equipment and surrounding devices, adjustment of post structure for improvement of die durability, and shear load distribution analysis are necessary. Based on these factors, highefficiency induction motor prototypes for 5.5kw, 7.5kw, 11kw, 4 polar, and 6 polar sharing cores are constructed.

Development of a High Speed Induction Motor for Spindle Systems

This paper deals with the analysis techniques of a high speed and high efficiency 10 kW, 30 000 rpm rated induction motor. The induction motor has been analyzed by the time-varying magnetic finite element method and the test results show that there is a possibility that the motor could be used in a high speed spindle system application. All performances of the prototype are successfully verified. All analysis techniques are introduced to develop a high speed and high efficiency induction motor made by copper die casting. The analysis techniques are composed of magnetic analysis, structural analysis, critical speed analysis, unbalance response analysis and computational fluid dynamics (CFD). CFD simulation results are compared with the experiment, and are within a 5% deviation.

An Analytical Approach for a High Speed and High Efficiency Induction Motor Considering Magnetic and Mechanical Problems

This paper deals with the analysis techniques of a high speed and high efficiency 10 kW, 30,000 rpm rated induction motor. The induction motor has been analyzed by time-varying magnetic finite element method and the test results show that there is a possibility that the motor could be used in a high speed spindle system application. All analysis techniques are introduced to develop a high speed and high efficiency induction motor made by copper die casting. The analysis techniques are composed of magnetic analysis considering losses and input current (PWM and sinusoidal), structural analysis of rotor and stator, 3-D rotordynamic analysis and 3-D CFD. All performances of the prototype are successfully verified.

Characteristic Requirements of a Small Scale Squirrel Cage Induction Generator for Effective Electricity Generation from Wind Energy

This paper proposes characteristic requirements of a small scale squirrel cage induction generator for effective electricity generation from wind energy. These characteristics are obtained from modeling and testing results. Investigation into comparative performances between Standard and high efficiency induction generators is given in order to find out the characteristic requirements of a suitable induction generator. Performances of various features of the machine structure are given. The suitable design of the induction generator based on empirical rules is also included. The investigation of power loss of the induction machine both in theory using FEM (Finite Element Method) and tests has been made. In addition, static var (Volt-Ampere reactive power) compensator using power electronic control to keep terminal voltage of a self-excited induction generator constant is explained. These results can be guidelines for machine development and control method for effective electricity generation.

RNase non-sensitive and endocytosis independent siRNA delivery system: delivery of siRNA into tumor cells and high efficiency induction of apoptosis

To date, RNase degradation and endosome/lysosome trapping are still serious problems for siRNA-based molecular therapy, although different kinds of delivery formulations have been tried. In this report, a cell penetrating peptide (CPP, including a positively charged segment, a linear segment, and a hydrophobic segment) and a single wall carbon nanotube (SWCNT) are applied together by a simple method to act as a siRNA delivery system. The siRNAs first form a complex with the positively charged segment of CPP via electrostatic forces, and the siRNA-CPP further coats the surface of the SWCNT via hydrophobic interactions. This siRNA delivery system is non-sensitive to RNase and can avoid endosome/lysosome trapping in vitro. When this siRNA delivery system is studied in Hela cells, siRNA uptake was observed in 98% Hela cells, and over 70% mRNA of mammalian target of rapamycin (mTOR) is knocked down, triggering cell apoptosis on a significant scale. Our siRNA delivery system is easy to handle and benign to cultured cells, providing a very efficient approach for the delivery of siRNA into the cell cytosol and cleaving the target mRNA therein.

Analysis of high speed induction motor for spindle made by copper die casting process

This paper deals with the analysis techniques of a high speed and high efficiency 10 kW, 30,000 rpm rated induction motor. The induction motor has been analyzed by time-varying magnetic finite element method and the test results show that there is a possibility that the motor could be used in a high speed spindle system application. All performances of the prototype are successfully verified. All analysis techniques are introduced to develop a high speed and high efficiency induction motor of copper die casting. The analysis techniques are composed of an electrical technique (magnetic analysis), and a mechanical technique (casting analysis, structural analysis, critical speed analysis and unbalance response analysis). Simulation results are compared with the experiment, and are within a 3% deviation.

Optimizing Design Variables for High Efficiency Induction Motor Considering Cost Effect by Using Genetic Algorithm

The characteristics of an induction motor vary with the number of parameters and the performance relationship between the parameters also is implicit. In case of the induction motor design, we generally should estimate many objective physical quantities in the optimization procedure. In this article, the multi objective design optimization based on genetic algorithm is applied for the three phase induction motor. The efficiency, starting torque, and material cost are selected for the objectives. The validity of the design results is also clarified by comparison between calculated results and measured ones.

Multi optimization of high efficiency induction motor considering cost effect

The characteristics of an induction motor vary depending upon the number of parameters and the performance relationship between the parameters is also implicit. In the case of the induction motor design, we should generally estimate the many objective physical quantities in the optimization procedure. In this article, the multi objective design optimization based on a genetic algorithm is applied for a three phase induction motor. The efficiency, starting torque, and material cost are selected as the objectives. The validity of the design results is also clarified by comparison between the calculated results and the measured ones.

산업체 전력다소비 설비의 수요관리 기여도 및 효율향상 보급에 대한 경제성 평가분석

Though electricity consumption amount in industry has been increased gradually, corresponding power supply show symptoms of marginal point. Importance of demand-side management from large-industries has also been raised. This paper deals with induction motor, which is one of representative examples of heavy electricity consumption utilities, to analyze potential technical capability, economic feasibility from consumers’ viewpoint and demand-side management feasibility from nation-wide perspective. Nation-wide economic feasibility analysis was done through California test, which has been used as demand-side management evaluation model. This paper also describes limitation of existing high efficiency induction motor in terms of contribution to demand-side management and utilizes premium motor to calculate demand-side management contribution level and economic feasibility evaluation. Likewise, this paper emphasizes the efficiency improvement of induction motor and analyzes how much premium motor related technologies can contribute to demand-side management.

Mesenchymal cell populations: development of the induction systems for Schwann cells and neuronal cells and finding the unique stem cell population

Mesenchymal cell populations, referred to as mesenchymal stem cells or multipotent stromal cells (MSCs), which include bone marrow stromal cells (BMSCs), umbilical cord stromal cells and adipose stromal cells (ASCs), participate in tissue repair when transplanted into damaged or degenerating tissues. The trophic support and immunomodulation provided by MSCs can protect against tissue damage, and the differentiation potential of these cells may help to replace lost cells. MSCs are easily accessible and can be expanded on a large scale. In addition, BMSCs and ASCs can be harvested from the patient himself. Thus, MSCs are considered promising candidates for cell therapy. In this review, I will discuss recently discovered high-efficiency induction systems for deriving Schwann cells and neurons from MSCs. Other features of MSCs that are important for tissue repair include the self-renewing property of stem cells and their potential for differentiation. Thus, I will also discuss the stemness of MSCs and describe the discovery of a certain stem cell type among adult MSCs that can self-renew and differentiate into cells of all three germ layers. Furthermore, I will explore the prospects of using this cell population for cell therapy.

高効率加熱を目的としたIH 負荷の磁気特性解析とモデリング

An IH cooking heater should have high efficiency heating and accept all metal pans. In order to develop the high efficiency induction heater for all metals, it is necessary to analyze magnetic characteristics of the working coil of IH cooking heater. However such an analysis has not been discussed until now. This paper presents a magnetic analysis for high efficiency induction heating, which can heat not only iron pans but also aluminum pans. The heating performance of IH cooking heater which heats both iron and aluminum pans is discussed with the analysis result of magnetic flux and eddy current distribution.

High-Efficiency Induction of Neural Conversion in Human ESCs and Human Induced Pluripotent Stem Cells with a Single Chemical Inhibitor of Transforming Growth Factor Beta Superfamily Receptors

Chemical compounds have emerged as powerful tools for modulating ESC functions and deriving induced pluripotent stem cells (iPSCs), but documentation of compound-induced efficient directed differentiation in human ESCs (hESCs) and human iPSC (hiPSCs) is limited. By screening a collection of chemical compounds, we identified compound C (also denoted as dorsomorphin), a protein kinase inhibitor, as a potent regulator of hESC and hiPSC fate decisions. Compound C suppresses mesoderm, endoderm, and trophoectoderm differentiation and induces rapid and high-efficiency neural conversion in both hESCs and hiPSCs, 88.7% and 70.4%, respectively. Interestingly, compound C is ineffective in inducing neural conversion in mouse ESCs (mESCs). Large-scale kinase assay revealed that compound C targets at least seven transforming growth factor beta (TGF-β) superfamily receptors, including both type I and type II receptors, and thereby blocks both the Activin and bone morphogenesis protein (BMP) signaling pathways in hESCs. Dual inhibition of Activin and BMP signaling accounts for the effects of compound C on hESC differentiation and neural conversion. We also identified muscle segment homeobox gene 2 (MSX2) as a downstream target gene of compound C and a key signaling intermediate of the BMP pathway in hESCs. Our findings provide a single-step cost-effective method for efficient derivation of neural progenitor cells in adherent culture from human pluripotent stem cells. Therefore, it will be uniquely suitable for the production of neural progenitor cells in large scale and should facilitate the use of stem cells in drug screening and regenerative medicine and study of early human neural development.

고효율 유도전동기 소형 모터코어 금형개발에 관한 연구

고효율 유도전동기는 일반 유도전동기의 발생 손실을 절감시킨 것으로 적은 소비전력으로 에너지를 절약하고, 운전비용이 낮아서 단기간에 초기 설비투자 비용회수가 가능하고, 온도상승이 크지 않아 전동기 수명을 연장시킬 수 있다. 이에 포스코아에서는 이제까지의 경험을 바탕으로 전기 연구원과 협력하여 고효율 유도전동기 개발에 나섰다. 본 논문에서는 고효율 유도전동기 소형모터금형개발에 관하여 연구하였다. The high-efficiency induction motor reduces the generation loss of conventional induction motors and saves energy with less electricity consumed, enabling the return of initial facilities investments on a shorter-term basis due to its low operation cost and allowing the extension of the life of the motor. Poscore has entered the phase of development of high-efficiency induction motor based on its experiences to date in cooperation with electricity researchers. This paper examines the development of the small motor die for the high-efficiency induction motor.