Artículos de revistas: "High Frequency Current Injection"

1

Harke, M. C., J. M. Guerrero, M. W. Degner, F. Briz y R. D. Lorenz. "Current Measurement Gain Tuning Using High-Frequency Signal Injection". IEEE Transactions on Industry Applications 44, n.º 5 (septiembre de 2008): 1578–86. http://dx.doi.org/10.1109/tia.2008.2002170.

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2

Liu, Zhao, Wang, Huang y Shi. "Compatibility Issues with Irregular Current Injection Islanding Detection Methods and a Solution". Energies 12, n.º 8 (17 de abril de 2019): 1467. http://dx.doi.org/10.3390/en12081467.

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Islanding detection methods, based on injecting high-/low-frequency currents or negative sequence fundamental frequency currents and observing the resultant responses, are collectively referred to as irregular current injection methods in this paper. In multi-distributed generation (DG) operation, if there is no restriction to the phase of injected irregular currents, the currents at the same frequency may cancel each other out, and then their convergent current may be too small to cause a detectable response, for which reason islanding detection will be severely affected. Accordingly, this paper raises a compatibility issue, which requires the phase difference between any two injected irregular currents to be within a certain interval. In response to this issue, a solution is proposed. According to this solution, the terminal voltage of DG units is referenced to conduct irregular currents injection, and only certain high-frequency currents are used as injected currents. If this solution is adopted by as many manufacturers as possible, the effect and reliability of such methods will be greatly improved.

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3

Kim, Dongouk, Yong-Cheol Kwon, Seung-Ki Sul, Jang-Hwan Kim y Rae-Sung Yu. "Suppression of Injection Voltage Disturbance for High-Frequency Square-Wave Injection Sensorless Drive With Regulation of Induced High-Frequency Current Ripple". IEEE Transactions on Industry Applications 52, n.º 1 (enero de 2016): 302–12. http://dx.doi.org/10.1109/tia.2015.2478887.

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4

Okano, Toshiki, Takuya Mitani, Akihiro Suwa, Yoshihiko Matsui, Masayuki Sakaki, Akiko Kumada y Kunihiko Hidaka. "DC Interruption Characteristics of VCB by Injection of High Frequency Current". IEEJ Transactions on Power and Energy 138, n.º 6 (1 de junio de 2018): 535–36. http://dx.doi.org/10.1541/ieejpes.138.535.

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5

Bhadra, D. K. y C. Chu. "RF current drive with magnetic helicity injection". Journal of Plasma Physics 33, n.º 2 (abril de 1985): 257–64. http://dx.doi.org/10.1017/s002237780000249x.

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External injection of magnetic helicity into a plasma may be possible through the introduction of appropriately polarized electromagnetic waves. A concept of steady-state current-drive is presented, based on the validity of conservation of helicity (appropriately defined for finite frequency processes). It is shown that such external injection of helicity can maintain a steady-state current by compensating the volt-seconds consumed through plasma resistivity. Such a mechanism, if experimentally successful, is particularly interesting at high densities because the efficiency of the process does not depend on plasma density, as opposed to other radio-frequency current-drive techniques.

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6

Li, Ke, Tianfu Sun, Fucheng Jiang, Wei Feng y Huiyun Li. "MTPA Control for IPMSM Drives Based on Pseudorandom Frequency-Switching Sinusoidal Signal Injection". Machines 10, n.º 4 (25 de marzo de 2022): 231. http://dx.doi.org/10.3390/machines10040231.

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Among various maximum torque per ampere (MTPA) control schemes for interior permanent magnet synchronous motor (IPMSM) drives, the signal-injection-based methods exhibit relatively high overall performance due to their high control accuracy and satisfactory dynamic performance. However, the high current spectrum peaks induced by the fixed-frequency signal injection may cause electromagnetic interference and even audible noise problems in applications, such as electric vehicles, vessels, and aircraft. To address this problem, an MTPA control method using pseudorandom frequency-switching sinusoidal signal injection is proposed in this paper. The sinusoidal signals with two different frequencies are randomly injected into the d- and q-axis currents and the MTPA points can be tracked according to the resultant system response. In this way, a high-performance MTPA control can be achieved regardless of motor parameter variations. Since the injection frequency of the proposed method varies randomly, the induced harmonic components in phase currents no longer concentrate at certain frequencies, and the current spectrum peaks caused by signal injection can be reduced accordingly. The experimental results demonstrate the validity of the presented method.

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7

Wang, Jian Min. "Performance of Pulsating High-Frequency Current Injection Based Sensorless Control of PMSM". Applied Mechanics and Materials 347-350 (agosto de 2013): 610–16. http://dx.doi.org/10.4028/www.scientific.net/amm.347-350.610.

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In the paper the principle and performances of the pulsating current injection based sensorless control of permanent magnet synchronous motor (PMSM) are analyzed theoretically and investigated by simulations. In the analyses, the effects of the speed EMF terms and the deviation between the actual d-axis high-frequency current and the command, which results from the limited gain and bandwidth of the current control loop, are all taken into account. It is shown that the pulsating current injection method can achieve stable position estimation in a wide speed range. But appreciable position errors will result at high speeds due to the cross-coupling effects of the speed EMFs and the tracking error between the actual and command carrier current. In order to improve the performance, a modified scheme is proposed. Its validity is confirmed by simulations.

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8

Seog-Joo Kang, Jang-Mok Kim y Seung-Ki Sul. "Position sensorless control of synchronous reluctance motor using high frequency current injection". IEEE Transactions on Energy Conversion 14, n.º 4 (1999): 1271–75. http://dx.doi.org/10.1109/60.815058.

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9

Reigosa, David Diaz, Daniel Fernandez, Hideo Yoshida, Takashi Kato y Fernando Briz. "Permanent-Magnet Temperature Estimation in PMSMs Using Pulsating High-Frequency Current Injection". IEEE Transactions on Industry Applications 51, n.º 4 (julio de 2015): 3159–68. http://dx.doi.org/10.1109/tia.2015.2404922.

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10

Cross, A. M. y A. J. Forsyth. "A high-power-factor, three-phase isolated AC-DC converter using high-frequency current injection". IEEE Transactions on Power Electronics 18, n.º 4 (julio de 2003): 1012–19. http://dx.doi.org/10.1109/tpel.2003.813781.

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11

Li, Yu Dong, Bo Zhou, Ying Liu y Cheng Liang Zhao. "Analysis and Simulation of Low Speed Sensorless Vector Control with Two Current Signal Injection Schemes". Advanced Materials Research 722 (julio de 2013): 361–68. http://dx.doi.org/10.4028/www.scientific.net/amr.722.361.

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Two current signal injection methods, the fluctuating high frequency (HF) current signal injection and low frequency (LF) current signal injection, were discussed. The basic principles of rotor position self-sensing using these current signal injection and the key techniques in implementation were presented and the simulation models for sensorless vector control systems of a permanent magnet synchronous motor (PMSM) were established using two proposed rotor position estimation methods. Comparative simulation study of the fluctuating HF current signal injection and LF current signal injection was investigated, and draw the conclusions that the saliency-tracking scheme using fluctuating HF current signal injection possesses simpler configuration and better speed-adjustable performance both in static and dynamic.

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12

Klein, M., D. J. W. Mous y A. Gottdang. "Fast and Accurate Sequential Injection AMS with Gated Faraday Cup Current Measurement". Radiocarbon 46, n.º 1 (2004): 77–82. http://dx.doi.org/10.1017/s0033822200039370.

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Sequential injection or bouncing has a number of properties which can lead to a reduction of the analysis accuracy if no appropriate measures are taken. A special injection system has been developed in order to eliminate these shortcomings. The influence of source glitches or instabilities on the measured isotopic ratio is substantially reduced by a high cycling frequency. A fast beam-blanking unit guarantees the needed accuracy of the injection periods. Background currents are avoided by synchronizing the current measurement for the stable isotopes with their injection periods. To achieve the required speed and precision of the gated measurement, new instrumentation was developed. The elimination of background contributions allows an efficiency for radiocarbon counting as high as 95% at a cycling frequency of 100 Hz.

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13

Teng, Yufei, Zhenyuan Zhang y Xiaopeng Li. "Improved Approach to High-Frequency Current Injection-Based Protection for Grounding Electrode Line in High-Voltage Direct Current System". IEEE Transactions on Industry Applications 56, n.º 3 (mayo de 2020): 2409–17. http://dx.doi.org/10.1109/tia.2020.2979960.

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14

Wu, Han, Yanzhou Sun, Xiaoqian Liu, Xiaoyan Song y Yanfang Wei. "The Signal Injection Method with High-Frequency for Distribution Network Capacitive Current Measurement". Journal of Electrical Engineering & Technology 16, n.º 2 (15 de febrero de 2021): 867–72. http://dx.doi.org/10.1007/s42835-020-00645-w.

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15

Zhong, Li Ping. "Research on rotating high-frequency current injection method based on LC resonance network". International Journal of Computer Applications in Technology 64, n.º 2 (2020): 143. http://dx.doi.org/10.1504/ijcat.2020.10033914.

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16

Zhong, Li Ping. "Research on rotating high-frequency current injection method based on LC resonance network". International Journal of Computer Applications in Technology 64, n.º 2 (2020): 143. http://dx.doi.org/10.1504/ijcat.2020.111607.

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17

Huang, Yuhao, Kai Yang y Cheng Luo. "Analysis on Position Estimation Error of Sensorless Control Based on Square-Wave Injection for SynRM Caused by Dead-Time Harmonic Current". Energies 15, n.º 24 (15 de diciembre de 2022): 9539. http://dx.doi.org/10.3390/en15249539.

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Sensorless control based on high-frequency square-wave voltage injection (HFSVI) is one of the most common sensorless control methods for synchronous reluctance motors (SynRMs). However, the injection frequency for SynRMs cannot be too high due to various factors. As the injection frequency decreases, the dead-time harmonic current will greatly affect the separation of high frequency signals. This paper analyzes the effect of dead-time harmonic current on the HFSVI-based sensorless control performance of SynRMs and proposes a source of position estimation error. Then, a dead-time compensation method suitable for filter-free HFSVI is proposed. It can estimate current vector spatial orientation without any low-pass filters (LPFs) and effectively compensate the impact of dead-time setting. The correctness of the theoretical analysis and the feasibility of the proposed methods in this paper are verified by experiments.

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18

Gan, Chun, Jianhua Wu, Shiyou Yang y Yihua Hu. "Phase Current Reconstruction of Switched Reluctance Motors From DC-Link Current Under Double High-Frequency Pulses Injection". IEEE Transactions on Industrial Electronics 62, n.º 5 (mayo de 2015): 3265–76. http://dx.doi.org/10.1109/tie.2014.2364153.

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19

Wang, Zhiqiang, Qi Guo, Jifeng Xiao, Te Liang, Zhichen Lin y Wei Chen. "High-Frequency Square Wave Injection Sensorless Control Method of IPMSM Based on Oversampling Scheme". World Electric Vehicle Journal 13, n.º 11 (18 de noviembre de 2022): 217. http://dx.doi.org/10.3390/wevj13110217.

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In view of the disadvantages of the traditional high-frequency square wave signal injection method in the low-speed operation of high-power interior permanent magnet synchronous motor (IPMSM), such as the large error of rotor position calculation and delay of position update, a method based on high-frequency square wave signal injection is proposed to obtain an effective vector action current through oversampling. When the vector is zero, the current changes to not zero, but when the vector is effective, the current changes greatly. In the traditional sampling and calculation methods, the change of the zero-vector is ignored, resulting in errors, especially in the case of small power, and the errors are more obvious. Through the method of oversampling the current of the effective vector, the high-frequency response current of the effective vector is obtained. Through the reasonable demodulation method, the high-frequency response current of the effective vector is extracted, and then the rotor position information is obtained through the phase-locked loop. On this basis, the influence of the inherent nonlinear characteristics of the motor system and the sampling delay on the calculation of the rotor position is analyzed, and the error is compensated to obtain a more accurate rotor position.

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20

Szalay, István, Dénes Fodor, Krisztián Enisz y Hunor Medve. "Permanent Magnet Synchronous Motor Model Extension for High-Frequency Signal Injection-Based Sensorless Magnet Polarity Detection". Energies 15, n.º 3 (3 de febrero de 2022): 1131. http://dx.doi.org/10.3390/en15031131.

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In this paper, a novel extended permanent magnet synchronous motor model is presented that incorporates a quadratic flux-current function to represent the polarity-dependent saliency. The proposed model enables the design of sensorless polarity detection algorithms required by the initial position detection of permanent magnet synchronous motors. The novelty of the model is that it integrates the polarity-dependent saliency into the traditional machine model and introduces a new machine parameter, the polarity-dependent saliency coefficient, to specify the Hessian matrix of the flux-current function. A measurement method is presented for determination of the elements of the Hessian and the polarity-dependent saliency coefficient. The solution of the model is given for high-frequency sinusoidal pulsating voltage injection. Experimental results show that the proposed extended model accurately predicts the amplitudes and phases of the second harmonics of the motor currents, which are the carriers of the polarity-dependent information. This information enables a current measurement-based polarity detection algorithm using the phase difference between the fundamental and second harmonic of the apparent d-axis current. Both the presented measurement data and the proposed model show that injection in the d-direction is optimal for polarity detection.

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21

Feng, Zhao y Peng Jiaqi. "Islanding Detection Based on High Frequency Injection for Multi Inverter Microgrid". Open Electrical & Electronic Engineering Journal 9, n.º 1 (4 de noviembre de 2015): 560–65. http://dx.doi.org/10.2174/1874129001509010560.

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Islanding detection is one of the indispensable protection detections for grid-connected inverters. The detection of islanding is the key factor that should be considered in the analysis of grid-connection security. The non-detection zone is the performance index of anti-islanding plan. According to the phase feature, quantitative analyses of the non-detection zone of several frequency disturbance schemes are conducted under several different coordinate systems by increasing disturbance, namely injecting third harmonic to the modulating wave that produces inverter drive signal and detects the voltage value and the total harmonic distortion of the power grid. The active current all-disturbance islanding detection scheme has been chosen as the initiative scheme of anti-islanding detection to complete the parameter design and simulation. According to the experimental result, this method is feasible to detect the island of microgrid. In this paper, the simulation model of islanding detection of microgrid is established through MATLAB/SIMULINK, and the simulation analysis of islanding phenomenon after the injection of third harmonic wave is conducted. The simulation result verifies the validity and availability of the islanding detection method.

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22

Sun, Yanzhou, Weilin Wu, Yining Sun, Xiaoyan Song y Han Wu. "Research on signal injection method with high frequency for distribution network capacitive current measurement". Electric Power Systems Research 195 (junio de 2021): 107135. http://dx.doi.org/10.1016/j.epsr.2021.107135.

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23

Odhano, Shafiq Ahmed, Paolo Giangrande, Radu Iustin Bojoi y Chris Gerada. "Self-Commissioning of Interior Permanent- Magnet Synchronous Motor Drives With High-Frequency Current Injection". IEEE Transactions on Industry Applications 50, n.º 5 (septiembre de 2014): 3295–303. http://dx.doi.org/10.1109/tia.2014.2309722.

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24

Martinez, Maria, David Reigosa, Daniel Fernandez, Juan M. Guerrero y Fernando Briz. "Enhancement of Permanent-Magnet Synchronous Machines Torque Estimation Using Pulsating High-Frequency Current Injection". IEEE Transactions on Industry Applications 56, n.º 1 (enero de 2020): 358–66. http://dx.doi.org/10.1109/tia.2019.2954297.

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25

Wakefield, Hilary E., Ralph F. Fregosi y Andrew J. Fuglevand. "Current injection and receptor-mediated excitation produce similar maximal firing rates in hypoglossal motoneurons". Journal of Neurophysiology 115, n.º 3 (1 de marzo de 2016): 1307–13. http://dx.doi.org/10.1152/jn.00848.2015.

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The maximum firing rates of motoneurons (MNs), activated in response to synaptic drive, appear to be much lower than that elicited by current injection. It could be that the decrease in input resistance associated with increased synaptic activity (but not current injection) might blunt overall changes in membrane depolarization and thereby limit spike-frequency output. To test this idea, we recorded, in the same cells, maximal firing responses to current injection and to synaptic activation. We prepared 300 μm medullary slices in neonatal rats that contained hypoglossal MNs and used whole-cell patch-clamp electrophysiology to record their maximum firing rates in response to triangular-ramp current injections and to glutamate receptor-mediated excitation. Brief pressure pulses of high-concentration glutamate led to significant depolarization, high firing rates, and temporary cessation of spiking due to spike inactivation. In the same cells, we applied current clamp protocols that approximated the time course of membrane potential change associated with glutamate application and with peak current levels large enough to cause spike inactivation. Means (SD) of maximum firing rates obtained in response to glutamate application were nearly identical to those obtained in response to ramp current injection [glutamate 47.1 ± 12.0 impulses (imp)/s, current injection 47.5 ± 11.2 imp/s], even though input resistance was 40% less during glutamate application compared with current injection. Therefore, these data suggest that the reduction in input resistance associated with receptor-mediated excitation does not, by itself, limit the maximal firing rate responses in MNs.

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26

Li, Dengke y Yukun Liu. "Research on Position Sensorless Vector Control of Synchronous Reluctance Motor Based on High Frequency Injection Method". Journal of Physics: Conference Series 2173, n.º 1 (1 de enero de 2022): 012055. http://dx.doi.org/10.1088/1742-6596/2173/1/012055.

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Abstract In order to achieve the high-performance control position sensorless vector control of synchronous reluctance motor (SynRM), this paper investigated its running-up performance and capability at zero or low speed range. The contribution of this paper mainly includes two parts. Firstly, it takes cross-saturation effect into consideration, Secondly, the paper improves the control stiffness and reliability under low-speed sensorless operation condition by adopting the pulsating sinusoidal high frequency voltage injection snesorless method. By injecting high-frequency voltage excitation signal, the rotor position is estimated from the high-frequency response current. The simulation results verified the feasibility of the control algorithm, and fulfilled the running-up of the SynRM at zero speed, the capability of stability is evaluated via simulation results.

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27

Tauchi, Yuki y Hisao Kubota. "Audible Noise Reduction Method in IPMSM Position Sensorless Control Based on High-Frequency Current Injection". IEEJ Journal of Industry Applications 4, n.º 3 (2015): 180–86. http://dx.doi.org/10.1541/ieejjia.4.180.

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28

Kapur, G. "Design of a High Frequency Stable Oscillator with Tunable Frequency using Field Programmable CMOS Current Conveyor". International Journal of Advance Research and Innovation 4, n.º 4 (2016): 33–38. http://dx.doi.org/10.51976/ijari.441606.

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Design of a programmable frequency oscillator design using field programmable, analog, CMOS current conveyor has been presented; further, a design methodology to introduce on-chip /field programmability into the second generation current controlled current conveyor circuit (CCCII) is explained. To make the CCCII CMOS design programmable, a floating-gate transistor synapse is introduced to replace the MOSFETs in the design. The charge at the floating-gate can be programmed after fabrication, based on Hot-e-injection and Fowler-Nordheim tunneling techniques. This programming charge at floating-gate results in threshold voltage variation in such floating-gate (FG) MOSFETs, which in turn can modifies circuit specifications after fabrication. The high frequency small signal analysis of the design has been discussed and specifications of the design are derived in terms of threshold voltages of the respective FG-MOSFETs. To achieve CCCII circuit’s AC and DC characteristics and to obtain programmable oscillations, the programmable CCCII and oscillator circuit using programmable CCCII, are simulated using BSIM3 level49 MOSFET models in T-Spice 0.35μm CMOS process. The simulated results show 13bit programming precision in current gain, 3dB bandwidth, input impedance, output impedance and dc offsets with respect to threshold voltage of respective FG-MOSFETs. Moreover on employing CCCII design with programmable current gain (about 0.91258- 1.2138) in an oscillator design with minimum passive components, variable amplitude oscillations can be generated.

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29

Wu, Jingbo, Yongwei Wang y Zhijun Guo. "Hybrid Pulse High-Frequency Voltage Injection Control Algorithm of Sensorless IPMSM for Vehicles". Computational Intelligence and Neuroscience 2022 (9 de septiembre de 2022): 1–9. http://dx.doi.org/10.1155/2022/4248643.

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A hybrid pulse vibration high-frequency voltage signal injection method is proposed to solve the problems that the conventional sensorless control algorithm of vehicle IPMSM may generate a large estimated rotor position error and opposite directions in identifying the polarity of magnetic poles under zero-speed and high-torque starting and low-speed operation. The magnetic pole polarity is identified by the saturation effect of the flux chain by injecting a high-frequency sinusoidal voltage signal and opposite pulse voltage signal into the axis d ^ of the assumed coordinate system simultaneously. Subsequently, the position relationship between the assumed d ^ axis and the actual d axis is studied in accordance with the amplitude of response current to acquire the rotor position and speed information. The simulation and experimental results suggest that the algorithm is capable of accurately identifying the magnetic pole polarity and estimating the rotor position at zero speed and low speeds, starting the motor smoothly at zero speed, and then operating the motor stably at low speeds.

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30

Piccardo, Marco, Michele Tamagnone, Benedikt Schwarz, Paul Chevalier, Noah A. Rubin, Yongrui Wang, Christine A. Wang et al. "Radio frequency transmitter based on a laser frequency comb". Proceedings of the National Academy of Sciences 116, n.º 19 (24 de abril de 2019): 9181–85. http://dx.doi.org/10.1073/pnas.1903534116.

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Since the days of Hertz, radio transmitters have evolved from rudimentary circuits emitting around 50 MHz to modern ubiquitous Wi-Fi devices operating at gigahertz radio bands. As wireless data traffic continues to increase, there is a need for new communication technologies capable of high-frequency operation for high-speed data transfer. Here, we give a proof of concept of a compact radio frequency transmitter based on a semiconductor laser frequency comb. In this laser, the beating among the coherent modes oscillating inside the cavity generates a radio frequency current, which couples to the electrodes of the device. We show that redesigning the top contact of the laser allows one to exploit the internal oscillatory current to drive a dipole antenna, which radiates into free space. In addition, direct modulation of the laser current permits encoding a signal in the radiated radio frequency carrier. Working in the opposite direction, the antenna can receive an external radio frequency signal, couple it to the active region, and injection lock the laser. These results pave the way for applications and functionality in optical frequency combs, such as wireless radio communication and wireless synchronization to a reference source.

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31

Abukari, S. S., S. Y. Mensah, R. Musah, M. Amekpewu, N. G. Mensah y K. W. Adu. "Enhanced nonlinear conductivity due to hot-electron injection in carbon nanotubes". Low Temperature Physics 48, n.º 7 (julio de 2022): 552–55. http://dx.doi.org/10.1063/10.0011603.

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We have theoretically obtained an expression for the current density in a terahertz field due to hot-electron injection in carbon nanotubes. The injection modifies the stationary distribution function and leads to a qualitative change in the behavior of the current-voltage characteristics and causes absolute negative conductivity. We compared the current-voltage characteristic behavior at different injection rates and observed a drastic change in the current density and absolute negative conductivity values. We propose that carbon nanotubes with hot-electron injection may be useful for high-frequency applications.

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32

Sal y Rosas, Damian, Daniel Chavez, David Frey y Jean-Paul Ferrieux. "Single-Stage Isolated and Bidirectional Three-Phase Series-Resonant AC–DC Converter: Modulation for Active and Reactive Power Control". Energies 15, n.º 21 (30 de octubre de 2022): 8070. http://dx.doi.org/10.3390/en15218070.

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Single-stage isolated and bidirectional (SSIB) AC–DC converters have a high potential for future solid-state transformers and smart battery chargers due to their reduced volume and high efficiency. However, there is a research gap for SSIB reactive power injection. This article introduces an SSIB three-phase AC–DC converter composed of three low frequency rectifiers linked by tiny film capacitors with a quad-active-bridge series-resonant (QABSR) DC–DC. A novel QAB modulation is proposed to solve three issues: (1) Three DC inputs with high ripple compensation, (2) active–reactive power injection, and (3) minimization of high-frequency (HF) transformers currents. The rectified grid voltages were modulated by time-variant duty ratio (DR) angles. In contrast, the DC source was modulated by a fixed DR (FDR) angle along with a phase-shift angle which changes according to the grid current amplitude. A constant HF current amplitude with minimum value was obtained. It is shown that the HF current amplitude is increased for reactive power injection. Hence, the FDR angle was used to compensate for this increase. Active and reactive power control were validated in a 2 kW prototype. Compared with other structures, tiny DC-link capacitors and smaller L filters were used. Moreover, higher efficiency (96%) and smaller grid currents THDi (3%) were obtained.

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33

Baharom, Rahimi y Mohammad Nawawi Seroji. "Dynamic analysis of the high-power factor three-phase AC to DC converter using current injection hybrid resonant Technique". International Journal of Power Electronics and Drive Systems (IJPEDS) 10, n.º 1 (1 de marzo de 2019): 538. http://dx.doi.org/10.11591/ijpeds.v10.i1.pp538-547.

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<span lang="EN-US">This paper presents the dynamic analysis of the high-power factor three-phase ac to dc converter using current injection hybrid resonant technique in order to investigate the characteristics of the output voltage, line current, DC-link voltage and the resonant current of the proposed converter. The dynamic analysis have been developed based on a separate analysis of the rectifier line-frequency operation and at the resonant circuit high-frequency. Converter circuit analysis have been performed based on the operation at the fundamental frequency. The power balance relation method has been included in order to match the line frequency equation with the high frequency resonant stage equation. This analysis can be envisaged to be the heart of the small-signal model to design the output voltage regulation and maintain a high-power factor input line current of the proposed converter.</span>

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34

Imai, Koji, Shinji Doki, Kosuke Kondo y Yasuaki Aoki. "Current Control System with High-Frequency Signal Injection for Dual Three-Phase Permanent Magnet Synchronous Motor". IEEJ Journal of Industry Applications 11, n.º 1 (1 de enero de 2022): 27–40. http://dx.doi.org/10.1541/ieejjia.20012955.

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35

HATANAKA, Hidekazu y T. NIVEN Gregory. "High Luminance, Current-Injection, Frequency-Doubled, Visible, Vertical External Cavity Surface Emitting Lasers and Illumination Applications". Review of Laser Engineering 42, n.º 7 (2014): 534. http://dx.doi.org/10.2184/lsj.42.7_534.

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36

Yamada, M. y T. Higashi. "Mechanism of the noise reduction method by superposition of high-frequency current for semiconductor injection lasers". IEEE Journal of Quantum Electronics 27, n.º 3 (marzo de 1991): 380–88. http://dx.doi.org/10.1109/3.81335.

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37

Choi, Chan-Hee y Jul-Ki Seok. "Compensation of Zero-Current Clamping Effects in High-Frequency-Signal-Injection-Based Sensorless PM Motor Drives". IEEE Transactions on Industry Applications 43, n.º 5 (2007): 1258–65. http://dx.doi.org/10.1109/tia.2007.904409.

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38

SKOWRON, Maciej y Ireneusz PIELECHA. "Optical tests as the basis for formulating mathematical models of the opening delay of CIDI injectors". Combustion Engines 171, n.º 4 (1 de noviembre de 2017): 185–92. http://dx.doi.org/10.19206/ce-2017-431.

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The main objective of this research was an attempt to evaluate the delay times of the actual needle opening of the diesel injectors in relation to the time of triggering the current control signals opening the solenoid and piezoelectric high-pressure injectors of diesel engines. The conducted tests take into account the variability of fuel injection pressure and backpressure prevailing in the operational chamber of the engine. To determine accurately the time of actual injection start, the optical tests analysing the image of the injector tip were used. Such high resolution images were obtained by high-speed recording with a frequency of 250 kHz (Dt = 0.004 ms). Based on a comparison of the results obtained, it was found that the maximum delay time of fuel injection for a piezoelectric diesel injector is about 12% shorter than for a solenoid injector. Experimentally obtained results of the injection time delay were used as a basis to formulate mathematical models describing the delay of the real fuel injection in relation to the signal controlling the opening of the diesel injectors. These models take into account the dependence of the injector reaction from the injection pressure and the backpressure in the operational chamber of the engine. The correctness of the obtained models is confirmed by acceptable values of the determination coefficient (for solenoid injector – 0.6, for piezoelectric injector – above 0.8 – for correlation of injection delay and backpressure).

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Pielecha, Ireneusz, Maciej Skowron y Krzysztof Wisłocki. "Mathematical models of delaying opening of SIDI injectors formulated on basis of optical tests". Combustion Engines 167, n.º 4 (1 de octubre de 2016): 8–21. http://dx.doi.org/10.19206/ce-2016-402.

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An appropriate moment of the fuel injection start is one of the parameters determining the characteristics of fuel flow from the injector and preparation of fuel-air mixture for combustion. However, knowledge of the characteristics of signals controlling the beginning of the injector opening does not provide enough information about the time of the actual fuel injection, which often leads to incorrect conclusions and decisions in relation to the required changes in the map of injection control. What was undertaken in this research was an attempt to evaluate the delay times of the actual opening of the high-pressure injectors of gasoline in relation to the time of triggering the current control signals opening the solenoid and piezoelectric injectors. The conducted tests take into account the variability of fuel injection pressure and backpressure prevailing in the operational chamber of the engine. To accurately determine the time of actual start of injection, the optical tests analysing the optical image of the tip of the dispenser were used. Such high resolution images were obtained thanks to high-speed filming with a frequency of 250 kHz (Dt = 0.004 ms). Correlation of the results of these analyses with the records of parameters of the fast-varying processes (voltage and current in the injector) allowed determining the times of the electric and hydraulic delay of the injection for piezoelectric and solenoid fuel injectors. Based on a comparison of the results obtained, it was found that the delay time of fuel injection for a piezoelectric injector of gasoline is about 3.5 times shorter than for a solenoid injector. It was also found that for the injection pressure above 10 MPa the delay is constant and does not depend on the pressure of fuel and the medium. Experimentally obtained results of the injection time delay were a basis to formulate mathematical models describing the delay of the actual fuel injection in relation to the signal controlling the opening of the injectors. These models take into account the dependence of the injector reaction on the injection pressure and the backpressure in the operational chamber of the engine. The correctness of the obtained models is confirmed by high values of the coefficient of determination (above 0.84).

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Chagnon, Jeffrey M. y Peter R. Bannon. "Adjustment to Injections of Mass, Momentum, and Heat in a Compressible Atmosphere". Journal of the Atmospheric Sciences 62, n.º 8 (1 de agosto de 2005): 2749–69. http://dx.doi.org/10.1175/jas3503.1.

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Abstract This study compares the response to injections of mass, heat, and momentum during hydrostatic and geostrophic adjustment in a compressible atmosphere. The sensitivity of the adjustment to these different injection types is examined at varying spatial and temporal scales through analysis of the transient evolution of the fields as well as the partitioning of total energy between acoustic waves, buoyancy waves, Lamb waves, and the steady state. The effect of a cumulus cloud on its larger-scale environment may be represented as a vertical mass source/sink and a localized warming. To examine how the response to such injections may differ, injections of mass and heat that generate identical potential vorticity (PV) distributions and, hence, identical steady states, are compared. When the duration of the injection is very short (e.g., a minute or less), the injection of mass generates a very large acoustic wave response relative to the PV-equivalent injection of heat. However, the buoyancy wave response to these two injection types is quite similar. The responses to injections of divergent momentum in the vertical and horizontal directions are also compared. It is shown that neither divergent momentum injection generates any PV and, thus, there is no steady-state response to these injections. The waves excited by these injections generally propagate their energy in the direction of the injection. Consequently, an injection of vertical momentum is an efficient generator of vertically propagating, horizontally trapped, high-frequency buoyancy waves. Such waves have a short time scale and are therefore very sensitive to the injection duration. Analogously, an injection of divergent horizontal momentum is an efficient generator of horizontally propagating, vertically trapped low-frequency buoyancy waves that are relatively insensitive to the injection duration. Because of this difference in the response to horizontal and vertical injections of momentum, the response to the injection of an isolated updraft differs depending on whether a compensating horizontal inflow/outflow is also specified. This additional specification of inflow/outflow helps filter acoustic waves and encourages a stronger updraft that is not removed as rapidly by the buoyancy waves. This finding is relevant to the initialization of updrafts in compressible numerical weather prediction models. Injection of nondivergent momentum generates waves in the regions of convergence/divergence produced by the deflection of the current by Coriolis forces. The energy partitioning for such an injection is sensitive to the width and depth of the current relative to the Rossby radius of deformation, but the response is insensitive to the duration of injection for time scales shorter than several hours.

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41

Nathan, A., E. Charbon, W. Kung y A. Salim. "Low-frequency noise correlations in lateral pnp bipolar transistors". Canadian Journal of Physics 70, n.º 10-11 (1 de octubre de 1992): 1112–17. http://dx.doi.org/10.1139/p92-180.

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Measurement results of low-frequency noise behaviour, and in particular, the noise correlations in lateral pnp bipolar transistors are presented for various bias conditions in both forward active and saturation regimes. The correlation in output collector noise is very high with a value close to unity only when the device is in medium injection. At extremely high injection, the degree of coherence degrades, depicting a behaviour similar to the forward current gain of the device. This degradation can be attributed to emitter-crowding effects. The correlation in output noise can be exploited to drastically suppress the intrinsic noise, particularly at low frequencies, making such devices useful for the input stage of amplifiers; the first step towards realisation of ultra low-noise amplifiers in standard integrated circuit technology.

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42

Jodkowski, J. S., F. Viana, T. E. Dick y A. J. Berger. "Repetitive firing properties of phrenic motoneurons in the cat". Journal of Neurophysiology 60, n.º 2 (1 de agosto de 1988): 687–702. http://dx.doi.org/10.1152/jn.1988.60.2.687.

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1. Using both rectangular- and ramp-shaped intracellularly injected currents, the repetitive firing properties of 23 antidromically identified phrenic motoneurons were determined in anesthetized, paralyzed, and artificially ventilated cats during hypocapnic apnea. In response to rectangular depolarizing current injections, regular repetitive firing was observed in all cells. 2. At the beginning of a rectangular current pulse, the firing pattern was characterized by high frequency of firing that rapidly adapted to a much lower steady-state value. The relationship between the reciprocal of the first interspike interval (F1-2) and injected current was described by an initial linear portion of shallow slope, followed by a much steeper segment that smoothly reached a plateau value. The plateau value of F1-2 did not change with further increase in injected current. 3. The steady-state firing frequency versus injected current relationship was represented by a line of shallow slope over the entire range of injected currents. The slope of this line ranged between 1.1 and 4.5 Hz/nA. 4. A weaker correlation between minimal firing frequency for continuous activity and the reciprocal of the after hyperpolarization duration (1/AHPdur) was found for phrenic motoneurons than exists for lumbosacral motoneurons (26). Comparison of AHP shape at different levels of repetitive firing revealed that the slopes of the ascending portions of the AHP were similar except at the higher injected currents. Further, in the same cells during natural inspiratory activity the ascending part of the AHP was similar to that observed during current injection. 5. Depolarizing current ramps (approximately 1-s duration) were injected into 11 phrenic motoneurons. Instantaneous firing frequency was directly proportional to the intensity of the instantaneous injected current and independent of the rate of change of current for the range of ramp slopes tested (5-80 nA/s). Ramp-and-hold current injections were done in three motoneurons, and the peak instantaneous firing frequency showed little adaptation during the hold maneuver. 6. During hypocapnic apnea, we mimicked the expiratory-phase inhibition and inspiratory-phase excitation of phrenic motoneurons by injecting a 1-s depolarizing current ramp that was immediately preceded by a 1-s hyperpolarizing current ramp of the same absolute peak current intensity. Compared with the effects of positive current ramps alone the spike onsets during the negative-positive current ramp paradigm were either facilitated or retarded. Various ionic mechanisms are suggested for these effects as well as their function in determining the onset of firing during natur

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43

Isakova, A. A., K. N. Savinov, N. N. Golovin, K. M. Sabakar, A. K. Dmitriev y A. A. Rundau. "Combined Microwave and High-Frequency Modulation of the Injection Current of a Diode Laser for Mutiple-Frequency Excitation of CPT-Resonances". Russian Physics Journal 63, n.º 1 (mayo de 2020): 171–75. http://dx.doi.org/10.1007/s11182-020-02016-4.

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44

Zhao, He, Liwei Zhang, Jie Liu, Chao Zhang, Jiao Cai y Lu Shen. "Design of a Low-Order FIR Filter for a High-Frequency Square-Wave Voltage Injection Method of the PMLSM Used in Maglev Train". Electronics 9, n.º 5 (28 de abril de 2020): 729. http://dx.doi.org/10.3390/electronics9050729.

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In position sensorless control based on a high-frequency pulsating voltage injection method, filters are used to complete the extraction of high-frequency response signals for position observation. A finite impulse response (FIR) filter has the advantages of good stability and linear phase. However, the FIR filter designed by using traditional methods has a high order which will cause a large time delay. This paper proposes a low-order FIR filter design method for a high-frequency signal injection method in the permanent magnet linear synchronous motor. Based on the frequency characteristics of the current signal, the requirement that the FIR filter needs to meet were analyzed. According to the amplitude–frequency characteristic of the FIR filter, these requirements were converted into constraint equations. By solving these equations, the coefficient of the FIR filter could be obtained. The simulation and experiment results showed the effectiveness of this low-order FIR filter.

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45

Chen, Junlei, Ying Fan, Wei Wang, Christopher H. T. Lee y Yueqi Wang. "Sensorless Control for SynRM Drives Using a Pseudo-Random High-Frequency Triangular-Wave Current Signal Injection Scheme". IEEE Transactions on Power Electronics 37, n.º 6 (junio de 2022): 7122–31. http://dx.doi.org/10.1109/tpel.2022.3140829.

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46

Reigosa, David, Daniel Fernandez, Tsutomu Tanimoto, Takashi Kato y Fernando Briz. "Comparative Analysis of BEMF and Pulsating High-Frequency Current Injection Methods for PM Temperature Estimation in PMSMs". IEEE Transactions on Power Electronics 32, n.º 5 (mayo de 2017): 3691–99. http://dx.doi.org/10.1109/tpel.2016.2592478.

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47

Zhou, Xiao Min, Xiang Hua Ma y Xin Qi. "Study on Wavelet De-Noising of High Frequency Current Signal for Rotor Position Self-Sensing of PMSM". Applied Mechanics and Materials 548-549 (abril de 2014): 1139–42. http://dx.doi.org/10.4028/www.scientific.net/amm.548-549.1139.

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Self-sensing control of permanent magnet synchronous motor has been a hot research topic of motor control technology, which has the advantages of low cost and high reliability. The use of a high-frequency carrier signal superimposed on the fundamental excitation of PMSM has established itself in recent years as a viable means of eliminating position sensors in ac drives for applications. In the carrier signal injection methods, the rotor position can be estimated by using the carrier signal current resulting from the interaction between the carrier signal voltage and the spatial saliency. The existing sampling error and random noise of high frequency current signal were uncertain to the rotor position self-sensing, that may affect the rotor position self-sensing precision. This paper describes a new wavelet de-noising method of the high-frequency current signal, improving the de-noising results significantly.

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48

He, Peng, Yiping Liang, Wei Qi, Libing Bai, Quan Zhou y Jie Zhang. "A high voltage capacitance measurement method based on alternating coupled signal injection". Review of Scientific Instruments 93, n.º 4 (1 de abril de 2022): 044704. http://dx.doi.org/10.1063/5.0085871.

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As high voltage pulse power capacitors, ceramic capacitors are widely used in high voltage pulse generators, trigger circuits, laser generators, and other fields. The capacitance of ceramic capacitors is closely related to the direct current (DC) bias voltage. However, the current capacitance measurement methods can only achieve a DC bias of 1 kV, which cannot meet the measurement requirements in high voltage environments. This paper proposes a capacitance measurement method that can accurately measure the capacitance under a DC bias of 3 kV. This method decouples the high DC bias voltage and high frequency alternating small signals and realizes low voltage calibration and high voltage isolation. The experimental results show that the proposed method measures the capacitance under a DC bias of 3 kV with a relative error within ±1%, which makes it possible to accurately quantify the capacitance hysteresis deviation in the process of increasing and decreasing back the voltage.

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49

Ren, Huiping, Li Fan, Na Liu, Zhengmao Wu y Guangqiong Xia. "Generation of Broadband Optical Frequency Comb Based on a Gain-Switching 1550 nm Vertical-Cavity Surface-Emitting Laser under Optical Injection". Photonics 7, n.º 4 (23 de octubre de 2020): 95. http://dx.doi.org/10.3390/photonics7040095.

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In this work, broadband optical frequency comb (OFC) generation by a gain-switching vertical-cavity surface-emitting laser (VCSEL) subject to optical injection is investigated experimentally. During implementing the experiment, a 1550 nm VCSEL under a large signal current modulation is driven into the gain-switching state with a broad noisy spectrum. By further introducing an optical injection, a high performance OFC can be produced. The experimental results demonstrate that the power and wavelength of the injection light seriously affect the performance of the produced OFC. Under proper optical injection parameters, two sub-combs originating from two orthogonal polarization components of the VCSEL can splice into a broadband total-OFC. By selecting optimized operation parameters, a high quality total-OFC can be acquired, with stable comb lines, high coherence, wide bandwidth of 70.0 GHz (56.0 GHz) within 10 dB (3 dB) amplitude variation and low single sideband phase noise at the fundamental frequency below −120.6 dBc/Hz @ 10 kHz.

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50

Vahedi, Hani, Abdolreza Sheikholeslami, Mohammad Tavakoli Bina y Mahmood Vahedi. "Review and Simulation of Fixed and Adaptive Hysteresis Current Control Considering Switching Losses and High-Frequency Harmonics". Advances in Power Electronics 2011 (28 de junio de 2011): 1–6. http://dx.doi.org/10.1155/2011/397872.

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Hysteresis Current Control (HCC) is widely used due to its simplicity in implementation, fast and accurate response. However, the main issue is its variable switching frequency which leads to extraswitching losses and injecting high-frequency harmonics into the system current. To solve this problem, adaptive hysteresis current control (AHCC) has been introduced which produces hysteresis bandwidth which instantaneously results in smoother and constant switching frequency. In this paper the instantaneous power theory is used to extract the harmonic components of system current. Then fixed-band hysteresis current control is explained. Because of fixed-band variable frequency disadvantages, the adaptive hysteresis current control is explained that leads to fixing the switching frequency and reducing the high-frequency components in source current waveform. Due to these advantages of AHCC, the switching frequency and switching losses will be diminished appropriately. Some simulations are done in MATLAB/Simulink. The Fourier Transform and THD results of source and load currents and the instantaneous switching frequency diagram are discussed to prove the efficiency of this method. The Fourier Transform and THD results of source and load currents are discussed to prove the validity of this method.

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