Results 251 to 260 of about 678,635 (303)
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2012
Prior to commissioning the first electrical power stations, electrical energy was mostly obtained from batteries, chemical sources of electrical current. The batteries provide DC voltages and currents at their output terminals. It is for this reason that the first experiments and applications of electrical machines have been made with DC current ...
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Prior to commissioning the first electrical power stations, electrical energy was mostly obtained from batteries, chemical sources of electrical current. The batteries provide DC voltages and currents at their output terminals. It is for this reason that the first experiments and applications of electrical machines have been made with DC current ...
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A Virtual DC Machine Control Strategy for Dual Active Bridge DC-DC Converter
2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia), 2019Dual active bridge (DAB) DC-DC converter has been widely used in the DC grid. A virtual DC machine control strategy (VDCM) for DAB DC-DC converter in DC distribution network is proposed in this paper, aiming at the DC voltage dip caused by sudden power change of micro-source, load switching and power disturbance of AC grid.
Yu Guo, Jianhui Meng, Yi Wang, Chen Wang
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1974
A rotating electrical machine may be manufactured in a few minutes using some copper wire, a battery and a few odds and ends. However, when the power required from a machine is increased, more sophisticated methods are necessary and ultimately the available technology is pushed to its limits.
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A rotating electrical machine may be manufactured in a few minutes using some copper wire, a battery and a few odds and ends. However, when the power required from a machine is increased, more sophisticated methods are necessary and ultimately the available technology is pushed to its limits.
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An analysis of DC‐machine commutation
Electrical Engineering in Japan, 1974The commutation equation is expressed in terms of state variables. An iterative method is proposed for solving it on the basis of periodic change of the commutation circuit. In the proposed method, the contact characteristics of the brush are fully taken into account. The validity of the method is confirmed experimentally using a 3-kw test machine.
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2009
This chapter contains sections titled: Introduction Solid-State Converters for dc Drive Systems Steady-State and Dynamic Characteristics of ac/dc Converter Drives One-Quadrant dc/dc Converter Drive Two-Quadrant dc/dc Converter Drive Four-Quadrant dc/dc Converter Drive Machine Control with Voltage-Controlled dc ...
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This chapter contains sections titled: Introduction Solid-State Converters for dc Drive Systems Steady-State and Dynamic Characteristics of ac/dc Converter Drives One-Quadrant dc/dc Converter Drive Two-Quadrant dc/dc Converter Drive Four-Quadrant dc/dc Converter Drive Machine Control with Voltage-Controlled dc ...
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GTO thyristor commutation of DC machine
Conference Record of the IEEE Industry Applications Society Annual Meeting, 2003The authors review the fundamental mechanism by which rotating electrical machines develop torque and draw conclusions as to which configuration offers inherent advantages in this regard. Development of a DC machine with a continuous armature winding where gate turn-off (GTO) thyristors replace the traditional copper-segment-carbon-brush commutator is ...
C.B. Gray, A. Ghaffary, A.M.H. Karim
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Characteristics of DC Machines
2012Working with DC machines requires the knowledge on their electrical and mechanical properties, parameters, and limitations. This chapter introduces and explains the concept of rated quantities and discusses the maximum permissible currents in continuous, steady-state service of DC machines. It also defines the safe operating area of DC machines in T em
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2015
In this chapter, the authors provide an overview of the issues related to losses and efficiency of D.C. machines. Speed control is then discussed. Solid state speed control is discussed afterwards. Speed Control using thyirstors. After finishing the discussion on speed control, the authors discuss braking DC motor, regenerative braking, dynamic braking,
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In this chapter, the authors provide an overview of the issues related to losses and efficiency of D.C. machines. Speed control is then discussed. Solid state speed control is discussed afterwards. Speed Control using thyirstors. After finishing the discussion on speed control, the authors discuss braking DC motor, regenerative braking, dynamic braking,
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Measurement of Inductance of DC Machines
IEEE Transactions on Power Apparatus and Systems, 1979Information is presented showing the general suitability of present measurement techniques outlined in IEEE Std 113-Standard Test Code for Direct Current Machines. The significance of machine parameters so determined is shown to be compatible with the most common usage of the application data. Revisions of the present test procedures are proposed.
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A Mathematical Model of a DC Machine
2005This research aims to determine how a mathematical model may predict the effects of a shorted and/or opened armature coil on a d-c machine. A mathematical model and a simulating computer were developed for a particular 0.375 kW d-c machine under both healthy and faulty conditions.\ \ The model was based on the coupled-coil theory, with a set of first ...
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