Results 291 to 300 of about 11,364,674 (354)

PSO-Based Optimization of DC-Link Current Harmonics in Traction VSI for an Electric Vehicle

IEEE transactions on industrial electronics (1982. Print), 2020
A large number of modern electric traction vehicles are equipped with drive systems based on induction motors fed by voltage source inverters (VSIs). This solution is known to be a significant source of interfering disturbances for a railway signaling ...
M. Steczek, P. Chudzik, M. Lewandowski, A. Szeląg   +3 more
semanticscholar   +1 more source

Current harmonics in nonlinear resistance circuits

Electrical Engineering, 1935
A semigraphical method of solving for harmonics in the input current to a network containing any number of linear and nonlinear resistances in any combination, when a sinusoidal voltage is applied across the network, is presented herewith. The treatment is restricted to nonlinear resistances in which the d-c volt-ampere characteristic is the same ...
openaire   +1 more source

Effects of Current Harmonics on Maximum Loading Capability for Solar Power Plant Transformers

2020 International SAUPEC/RobMech/PRASA Conference, 2020
Distribution transformers are commonly designed and manufactured to operate at fundamental frequency and to facilitate sinusoidal loads. The operation of loads that draw distorted currents culminate in higher losses, hotspot temperatures, degradation of ...
Dr Bonginkosi Thango, J. Jordaan, A. Nnachi   +2 more
semanticscholar   +1 more source

A study on randomly varying harmonic currents and total harmonic distortion of currents in power systems

2005 International Conference on Future Power Systems, 2005
Harmonic analysis is an important application to power systems and an efficient approach to evaluate the injected total harmonic distortion (THD) of currents flowing into a power system due to the summation of randomly varying harmonic currents produced by AC-to-DC power converters is presented in this paper.
null Li Wang, null Kuo-Hua Liu
openaire   +1 more source

Harmonic measurements: current and voltage transducers

199 IEEE Power Engineering Society Summer Meeting. Conference Proceedings (Cat. No.99CH36364), 2003
An overview of the development of special current and voltage transducers at the National Research Council of Canada for accurate measurements of harmonics in power systems will be presented. The transducers include two-stage and electronically-aided instrument transformers, openable-core AC and AC/DC current transformers, multi-stage clamp-on current ...
openaire   +1 more source

Voltage and current harmonics caused by corona

Journal of the American Institute of Electrical Engineers, 1921
THE FOLLOWING investigation was made to study the effects of corona in producing voltage and current harmonics in transmission systems. In the early work on corona in 1910 a very complete oscillographic study was made of voltage and current. It was found that the current wave of corona loss very much resembled the excitation current wave of a ...
openaire   +1 more source

Divisors and Harmonic Currents

2001
In the first two sections of the present chapter we introduce a conjecture (Conjecture 7.1) which specifies the idea that the characterization of the divisor of the Selberg zeta function of the a-twisted geodesic flow proved in Chapter 3 Section 3.3 is related to its characterizations in terms of a-twisted harmonic currents on SX.
openaire   +1 more source

Transformer inrush - Harmonics in the current

2018 19th International Scientific Conference on Electric Power Engineering (EPE), 2018
When transformer is energized, a transient current up to 10 to 15 times larger than the rated transformer current can flow for several cycles. The differential protections are mainly sensitive during this time, as the inrush current flows just on one site of the transformer and so it creates false differential current.
Bermann Jiri, Prochazka Martin
openaire   +1 more source

Even harmonics in alternating-current circuits

Proceedings of the American Institute of Electrical Engineers, 1909
In the usual presentation and consideration of wave-forms in alternating-current circuits we are so used to the mathematical expressions which omit the second, fourth, sixth, etc. harmonics and so generally assume that these even harmonics can be neglected at the outset, that a short consideration of usual and special conditions, giving rise to even ...
openaire   +1 more source

Modeling, analysis and suppression of current harmonics of Langevin-type ultrasonic motors under high voltage

, 2020
For achieving high speed and large thrust, Langevin-type ultrasonic motors (LTUM) are generally operated under high voltage. However, high voltage causes the current harmonics of piezoelectric material nonlinear phenomena, which will decrease the ...
Xiaoniu Li, Z. Yao, Mi Yuan, Xiaogang Lin, Chenguang Liang, Dawei Wu   +5 more
semanticscholar   +1 more source