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00233 Fuzzy detection of high impedance faults in radial distribution feeders
06
Electrical power supply and utilization (scientific, technical)
practical Indian power systems and modified IEEE 30 bus system. The performance of the fuzzy system is compared with conventional optimization technique and results ohtained are encouraging. Results obtained for a 82 node Indian power network and modified IEEE 30 bus system are presented for illustration purposes.
Fabrication and characteristics of a composite 00/00228 cathode of sulfonated polyaniline and Ramsdellite-MnOz for a new rechargeable lithium polymer battery
Hwang, K. S. et al. .I. Power Sowces. 1999, 79, (2), 225-230. The ionic conductivity of a polyacrylonitrile (PAN)-based solid polymer electrolyte is 1.4 x 10-l S cm-‘, which is sufficient for the electrolyte to be used in a rechargeable lithium polymer battery. The anodic stability of the solid polymer electrolyte is over 4.6 V (versus Li/Li+). A reduced, highly sulfonated form of polyaniline (SPAn) and Ramsdellite-MnO: (R-Mn02) are synthesized and used as a cathodic material for a rechargeable lithium polymer battery. Three kinds of cathodes are prepared from SPAn, RMnO, and a mixture of SPAn and R-MnO?. The electrochemical properties and diffusion coefficient of lithium ions in each cathode. and the interface between the solid polymer electrolyte and each cathode are investigated by cyclic voltammetry and impedance spectroscopy. The redox processes of the SPAn cathode are two-step reactions, The cathodic and anodic peak currents increase as the cycle number increases. In the redox processes of the R-MnOZ cathode. the cathodic peak current on the second cycle is 62% of that on the first cycle. The LiiR-MnOl battery has a very high initial discharge capacity but very poor cycleability. For the composite cathode, the cathodic peak current on the second cycle is 72% of that on the first cycle, i.e., higher than that for the R-MnO, cathode. The diffusion coefficient of the composite cathode during the discharge process is close to the sum of each variation in the SPAn and R-MnOZ cathodes. The instability of the R-MnO? cathode at x = 0.3 and x = 0.2 during the charge process is not ohserved with the composite cathode. The discharge-charge performance of three types of battery are investigated. The initial discharge capacity of the Liicomposite cathode battery is 97.0 m Ah gg’. This battery has higher discharge capacity than the LiSPAn battery (oh.8 m Ah gg’), and better cycleability than the LiiR-MnO? battery.
Fault analysis of Ar-Cs segmented-loading disk magnetohydrodynamics generator connected to electric power system
00100229
Kang. L. et al. Etter-p Cottvetx Manage.. 2000, 41. (1). 25-36. The authors study numerically an interconnecting system hetween the segmented-loading argon-caesium closed cycle disk magnetohydrodvnamics (MHD) generator and an infinite hus through the line-commutated mverter system and double-circuit power transmission line when faults occur at the inverter system and the power transmission line. Simulation results at the inverter fault condition show that misfiring of the inverter at not only the downstream but also the upstream results in a large disturbance at the downstream in various quantities of the generator. The firing angle control is very important to recover the operating condition of the MHD generator. Simulation results at the power line fault condition show that the inverters become out of operation, and ionization instability of the plasma is induced in the MHD generator when the fault occurs. When the fault is removed, the MHD generator can be recovered by means of the firing angle control of the inverters.
00100230
A fault location
method for parallel transmission
lines Sheng, L. B. and Elangovan, S. Ekctrical Power & Etwgy Systems. 1999, 21.14). 253-260. This paper presents a fault location method for one of two individually transposed parallel transmission lines. This method only utilizes voltage and current data acquired at one common end of the two lines to estimate the equivalent source impedance at the remote end. Therefore, the current through a fault resistance in the fault-path can be computed and the effects of the fault resistance and source impedance of the remote system on the accuracy of fault location can be eliminated. However, this method requires that: (1) a fault occurs only on one of the two parallel lines; and (2) the unfaulted line remains in operation until the fault is cleared.
From Bi4VzO11 to Li28Bi4V2011 by electrochemical lithium insertion: versatile applications in lithium batteries $N;;J y de Dompablo, M. E. et al. Int. J. Inorganic Materials, 1999, 1, (I), OOlOO231
Fuel cells: the clean energy of the future 00100232 Gresles. 0. Gaz dbujnurd’hui, 1999. 123, (7-9), 13-16. (In French) It is under this heading that ATG Ouest and the Ecole des Mines de Nantea organized a conference bringing together around one hundred participants. At this meeting. the first on this topic held hy a regional ATG branch. experts presented the range of fuel cell applications, including fixed installations for decentralized power generation or cogeneration and onboard systems for use in transport. This article summarizes the topics presented during the meeting. which was chaired by Gerard Fallot, chairman of ATG Ouest.
00100233
distribution
24
Fuel and Energy Abstracts
January 2000
of high impedance
faults in radial
Rev.. 1999. 49. (3) IhO-174. Jota, P. R. S. and Jota. F. G. Elec. Poww.~y.rt. The paper presents a methodology for the detection of high impedance faults in radial distribution feeders. The technique consists of making comparative analysis of the responses of the feeder to pulses injected at the feeder inlet for different configurations. The responses to normal configurations constitute the set, hereafter called ‘standard responses’ of the feeder under test. An artificial neuron set, composed of ‘neo-fuzzy’ neurons, is trained to recognize the standard responses. After the training period, the neuron-set becomes the decision core of the supervisory system. Subsequently, the supervisory system is used to monitor the feeder in real time. The feeder responses are periodically analvsed by the neuron-set. which classifies them according to the ‘pre-defined’ standard responses. In this way, non-standard configurations arc not classified. Simulation and experimental studies have shown that the proposed system is capable of recognizing passive high impedance faults even when thev occur clo\c to a switch (used to change configuration). In order to ~corrohorate the efficiency of the proposed methodology. experimental tcrts have hecn accomplished in a real feeder. They have shown satisfactory result\.
00100234
harmonic
Fuzzy linear regression for measurement components in a power system
of
Soliman, S. A. et rrl. Elec. Power Sw. RcT.. 1999. SO. (2). 99-105. A new approach for the measurement of power system harmonic components is described: it is hased on fuzzy linear regression. In this approach, the non-sinusoidal voltage or current waveform is written as a linear function. The coefficients of this function are assumed to be fuzzy numbers having a certain middle and spread value. The prohlem is formulated as a linear optimization problem. where the objective i\ to minimize the spread of voltage or current samples. Effects of critical parameters on the proposed algorithm are studied in the text. The proposed approach is tested using several numerical tests, which form the hasis to the conclusions at the end of the paper.
OOiOO235
cadmium
On the growth of Li2C03 dendrites industrial batteries
in nickel-
Palmqvist, U. and Sjiivall. R. J. Power Sources, 1999, 79. (2). 212-214. A large amount of LizCOJ dendrites has heen detected on positive electrodes in Ni-Cd industrial pocket plate batteries. intended to work in stationary applications, after 3years in float charge. The lattice parameters were refined to a = 8.353(I) A. h = 4.974( I) A. c = h.194( 1) A and j = 114.6(l) A [monoclinic]. which is in complete agreement with structural data reported in the literature. Oxidation of graphite present in the positive active material is enhanced at elevated temperatures and at high anodic potentials. This results in an extremely high carbonate concentration in the active material, as well as in the electrolyte. The high carbonate content, in combination with the relatively high lithium concentration present in hoth electrolyte and positive electrode. is very likely to be the reason for the formation of the L&CO3 dendrites. As this process continues, agglomerates of the dendrites in combination with attached &Cd(OH): and graphite may generate short circuits between the positive and the negative electrodes.
OOiOO236
estimation
Handling process
small unobservable
pockets
in state
Mesut, M. et ol. Elec. Poaw Sy.st. Res., 1999. 50. (I ), 17-X. Most power systems have pockets where not all flows and injects are measured and therefore, a part of the svstem is not observable. The manner in which these pockets are handled duhng the state estimation process mav make a significant difference in the outcome of the state estimation. This paper addresses the problems arising from such small pockets in a power system and provides a method for handling small pockets.
00100237 The compound Bi4V~OII has been tested as a positive electrode in room temperature electrochemical lithium cells. When the cells are discharged down to 0.5 V the reaction of Bi4V20,, with 28 lithium ions develops a theoretical specific capacity of 700 A h kgg’. Hence, this compound could be used as cathode in primary lithium batteries. Besides, the fact that in the low voltage region (1.3-0.5 V) Li2”Bi,VzOlI develops about 360 A h kg-’ at 0.7 V, and, therefore, this material is proposed as a negative electrode in lithium ion hatteries. The mechanism of the reaction of BiAV20,, with 28 lithium ions is not yet fully understood. although some guidelines can be given.
Fuzzy detection feeders
seoarator
How compressible mat?
is recombinant
battery
Pendry, C. J. Power Sowces, 1999. 78. (l-l), 54-64. In the past few years, the recombinant hattery separator mat (RBSM) for valve-regulated lead/acid (VRLA) batteries has become the focus of much attention. Compression, and the ability of microglass separators to maintain a level of ‘springiness’ have helped reduce premature capacity loss. As higher compressions are reached, it needs to determine what, if any. damage can be caused during the assemhly process. This paper reviews the findings when RBSM materials, with different surface area\. are compressed under forces up to 500 kPa in the dry state.
Electrical power supply and utilization (scientific, technical)
practical Indian power systems and modified IEEE 30 bus system. The performance of the fuzzy system is compared with conventional optimization technique and results ohtained are encouraging. Results obtained for a 82 node Indian power network and modified IEEE 30 bus system are presented for illustration purposes.
Fabrication and characteristics of a composite 00/00228 cathode of sulfonated polyaniline and Ramsdellite-MnOz for a new rechargeable lithium polymer battery
Hwang, K. S. et al. .I. Power Sowces. 1999, 79, (2), 225-230. The ionic conductivity of a polyacrylonitrile (PAN)-based solid polymer electrolyte is 1.4 x 10-l S cm-‘, which is sufficient for the electrolyte to be used in a rechargeable lithium polymer battery. The anodic stability of the solid polymer electrolyte is over 4.6 V (versus Li/Li+). A reduced, highly sulfonated form of polyaniline (SPAn) and Ramsdellite-MnO: (R-Mn02) are synthesized and used as a cathodic material for a rechargeable lithium polymer battery. Three kinds of cathodes are prepared from SPAn, RMnO, and a mixture of SPAn and R-MnO?. The electrochemical properties and diffusion coefficient of lithium ions in each cathode. and the interface between the solid polymer electrolyte and each cathode are investigated by cyclic voltammetry and impedance spectroscopy. The redox processes of the SPAn cathode are two-step reactions, The cathodic and anodic peak currents increase as the cycle number increases. In the redox processes of the R-MnOZ cathode. the cathodic peak current on the second cycle is 62% of that on the first cycle. The LiiR-MnOl battery has a very high initial discharge capacity but very poor cycleability. For the composite cathode, the cathodic peak current on the second cycle is 72% of that on the first cycle, i.e., higher than that for the R-MnO, cathode. The diffusion coefficient of the composite cathode during the discharge process is close to the sum of each variation in the SPAn and R-MnOZ cathodes. The instability of the R-MnO? cathode at x = 0.3 and x = 0.2 during the charge process is not ohserved with the composite cathode. The discharge-charge performance of three types of battery are investigated. The initial discharge capacity of the Liicomposite cathode battery is 97.0 m Ah gg’. This battery has higher discharge capacity than the LiSPAn battery (oh.8 m Ah gg’), and better cycleability than the LiiR-MnO? battery.
Fault analysis of Ar-Cs segmented-loading disk magnetohydrodynamics generator connected to electric power system
00100229
Kang. L. et al. Etter-p Cottvetx Manage.. 2000, 41. (1). 25-36. The authors study numerically an interconnecting system hetween the segmented-loading argon-caesium closed cycle disk magnetohydrodvnamics (MHD) generator and an infinite hus through the line-commutated mverter system and double-circuit power transmission line when faults occur at the inverter system and the power transmission line. Simulation results at the inverter fault condition show that misfiring of the inverter at not only the downstream but also the upstream results in a large disturbance at the downstream in various quantities of the generator. The firing angle control is very important to recover the operating condition of the MHD generator. Simulation results at the power line fault condition show that the inverters become out of operation, and ionization instability of the plasma is induced in the MHD generator when the fault occurs. When the fault is removed, the MHD generator can be recovered by means of the firing angle control of the inverters.
00100230
A fault location
method for parallel transmission
lines Sheng, L. B. and Elangovan, S. Ekctrical Power & Etwgy Systems. 1999, 21.14). 253-260. This paper presents a fault location method for one of two individually transposed parallel transmission lines. This method only utilizes voltage and current data acquired at one common end of the two lines to estimate the equivalent source impedance at the remote end. Therefore, the current through a fault resistance in the fault-path can be computed and the effects of the fault resistance and source impedance of the remote system on the accuracy of fault location can be eliminated. However, this method requires that: (1) a fault occurs only on one of the two parallel lines; and (2) the unfaulted line remains in operation until the fault is cleared.
From Bi4VzO11 to Li28Bi4V2011 by electrochemical lithium insertion: versatile applications in lithium batteries $N;;J y de Dompablo, M. E. et al. Int. J. Inorganic Materials, 1999, 1, (I), OOlOO231
Fuel cells: the clean energy of the future 00100232 Gresles. 0. Gaz dbujnurd’hui, 1999. 123, (7-9), 13-16. (In French) It is under this heading that ATG Ouest and the Ecole des Mines de Nantea organized a conference bringing together around one hundred participants. At this meeting. the first on this topic held hy a regional ATG branch. experts presented the range of fuel cell applications, including fixed installations for decentralized power generation or cogeneration and onboard systems for use in transport. This article summarizes the topics presented during the meeting. which was chaired by Gerard Fallot, chairman of ATG Ouest.
00100233
distribution
24
Fuel and Energy Abstracts
January 2000
of high impedance
faults in radial
Rev.. 1999. 49. (3) IhO-174. Jota, P. R. S. and Jota. F. G. Elec. Poww.~y.rt. The paper presents a methodology for the detection of high impedance faults in radial distribution feeders. The technique consists of making comparative analysis of the responses of the feeder to pulses injected at the feeder inlet for different configurations. The responses to normal configurations constitute the set, hereafter called ‘standard responses’ of the feeder under test. An artificial neuron set, composed of ‘neo-fuzzy’ neurons, is trained to recognize the standard responses. After the training period, the neuron-set becomes the decision core of the supervisory system. Subsequently, the supervisory system is used to monitor the feeder in real time. The feeder responses are periodically analvsed by the neuron-set. which classifies them according to the ‘pre-defined’ standard responses. In this way, non-standard configurations arc not classified. Simulation and experimental studies have shown that the proposed system is capable of recognizing passive high impedance faults even when thev occur clo\c to a switch (used to change configuration). In order to ~corrohorate the efficiency of the proposed methodology. experimental tcrts have hecn accomplished in a real feeder. They have shown satisfactory result\.
00100234
harmonic
Fuzzy linear regression for measurement components in a power system
of
Soliman, S. A. et rrl. Elec. Power Sw. RcT.. 1999. SO. (2). 99-105. A new approach for the measurement of power system harmonic components is described: it is hased on fuzzy linear regression. In this approach, the non-sinusoidal voltage or current waveform is written as a linear function. The coefficients of this function are assumed to be fuzzy numbers having a certain middle and spread value. The prohlem is formulated as a linear optimization problem. where the objective i\ to minimize the spread of voltage or current samples. Effects of critical parameters on the proposed algorithm are studied in the text. The proposed approach is tested using several numerical tests, which form the hasis to the conclusions at the end of the paper.
OOiOO235
cadmium
On the growth of Li2C03 dendrites industrial batteries
in nickel-
Palmqvist, U. and Sjiivall. R. J. Power Sources, 1999, 79. (2). 212-214. A large amount of LizCOJ dendrites has heen detected on positive electrodes in Ni-Cd industrial pocket plate batteries. intended to work in stationary applications, after 3years in float charge. The lattice parameters were refined to a = 8.353(I) A. h = 4.974( I) A. c = h.194( 1) A and j = 114.6(l) A [monoclinic]. which is in complete agreement with structural data reported in the literature. Oxidation of graphite present in the positive active material is enhanced at elevated temperatures and at high anodic potentials. This results in an extremely high carbonate concentration in the active material, as well as in the electrolyte. The high carbonate content, in combination with the relatively high lithium concentration present in hoth electrolyte and positive electrode. is very likely to be the reason for the formation of the L&CO3 dendrites. As this process continues, agglomerates of the dendrites in combination with attached &Cd(OH): and graphite may generate short circuits between the positive and the negative electrodes.
OOiOO236
estimation
Handling process
small unobservable
pockets
in state
Mesut, M. et ol. Elec. Poaw Sy.st. Res., 1999. 50. (I ), 17-X. Most power systems have pockets where not all flows and injects are measured and therefore, a part of the svstem is not observable. The manner in which these pockets are handled duhng the state estimation process mav make a significant difference in the outcome of the state estimation. This paper addresses the problems arising from such small pockets in a power system and provides a method for handling small pockets.
00100237 The compound Bi4V~OII has been tested as a positive electrode in room temperature electrochemical lithium cells. When the cells are discharged down to 0.5 V the reaction of Bi4V20,, with 28 lithium ions develops a theoretical specific capacity of 700 A h kgg’. Hence, this compound could be used as cathode in primary lithium batteries. Besides, the fact that in the low voltage region (1.3-0.5 V) Li2”Bi,VzOlI develops about 360 A h kg-’ at 0.7 V, and, therefore, this material is proposed as a negative electrode in lithium ion hatteries. The mechanism of the reaction of BiAV20,, with 28 lithium ions is not yet fully understood. although some guidelines can be given.
Fuzzy detection feeders
seoarator
How compressible mat?
is recombinant
battery
Pendry, C. J. Power Sowces, 1999. 78. (l-l), 54-64. In the past few years, the recombinant hattery separator mat (RBSM) for valve-regulated lead/acid (VRLA) batteries has become the focus of much attention. Compression, and the ability of microglass separators to maintain a level of ‘springiness’ have helped reduce premature capacity loss. As higher compressions are reached, it needs to determine what, if any. damage can be caused during the assemhly process. This paper reviews the findings when RBSM materials, with different surface area\. are compressed under forces up to 500 kPa in the dry state.