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The performances of a frequency doubler based on a distributed amplifier are evaluated experimentally. The gate and drain artificial transmission lines have band-pass filter frequency behavior, centered on the fundamental and second harmonic, respectively. The circuit topology of this frequency doubler makes possible a significant reduction of the power level for the output fundamental and third harmonics...
This paper analyzes a new architecture of the AC/DC type power supply for data centers. The source cumulates the following functions: three-phase current rectification, transformation of voltage parameters and DC voltage stabilization. The source ensures the reactive power compensation and does not distort the currents in the power three-phase network. The transfer of power from the alternating current...
With ever increasing requirements on the linearity of SAW signal processing devices in mobile communication, nonlinear effects like harmonic generation and intermodulations have gained renewed interest and have become an active field of research with the aim of identifying their origin, analyzing and counteracting them. In this contribution we focus on second-harmonic generation in SAW resonators...
Nonlinear generation of harmonics is measured on the wafer level on temperature compensated surface-acoustic-wave resonators on lithium niobate. The second-harmonic response features strong peaks looking like multiple resonant modes. The product of the frequency difference between the successive peaks to the substrate thickness is found to remain almost constant. The results also show that the level...
ISOV (Input Series Output Parallel) modular DAB (Dual Active Bridge) converter based topologies have been mostly considered for solid-state transformer (SST) based power substation design, involving multilevel converters at the medium-voltage side. As DAB converter is one of the core components of this topology, an important question to address is thus the freewheeling currents of DAB which increases...
High harmonic generation (HHG) is a promising tabletop source of coherent short wavelength radiation, with applications spanning science and engineering [1]. However, the low conversion efficiency and low average power of conventional few-kHz near-infrared (NIR) driving lasers limits the photon flux of such sources. Scaling this technique to MHz driving lasers requires strong focusing due to the limited...
Table-top extreme ultraviolet (XUV) light sources with laser like properties are of interest in a vast variety of applications. To achieve such light pulses with femtosecond pulse durations, high harmonic generation (HHG) is an established technique. It delivers ultrashort pulses and a wide range of photon energies, suitable for the study of core level transitions, highly excited states, or transitions...
Multi-photon processes are extremely important in optics. Optical harmonics generation, multi-photon absorption, ionization, polymerization or spectroscopy are widely used in practical applications. The efficiency of these processes depends on many factors, one of them being the statistics of the incident light. Indeed, the rate of an n-photon effect scales as the nth-order autocorrelation function...
Relationships between the desired load characteristics and parameters of the elements of the power unit of the frequency converter on the basis of the resonant inverter with nonlinear control were studied. Analytical dependences of these parameters on the specified load characteristics were received. Static and dynamic characteristics of the frequency converter with the parameters, computed in accordance...
In the new energy power generation, software phase locked loop is an important part of the grid connected converter. In the unbalanced and harmonic power system, the accuracy and speed of traditional phase locked loop is unable to meet the needs of high performance converter at the same time. The frequency conversion PLL based on frequency conversion filter and amplitude phase compensation precisely...
Due to the intermittent nature of wind, the power quality of the grid with wind power plants is affected. Hence, in order to assure the power quality of Adama-One wind farm, the continuous performance assessment is recommended using various performance indices. Two aspects of the wind farm performance evaluations are assessed. The first aspect is the evaluation of power and energy production performance...
This paper presents a low-complexity calibration-free digital PLL architecture. The PLL adopts a fractional frequency divider with a harmonic rejection current steering phase interpolator which is free from pre- and background-calibration. The harmonic rejection technology could improve linearity of interpolator. A simplified glitch-free control logic for fractional operation is proposed to lower...
The sending and receiving circuit is designed in this paper for ground-based coherent high-frequency radar. The system has some functions such as antenna aperture standing wave detection, final-stage power amplifier temperature detection and detection of various power source voltages and currents; it is capable of outputting large standing-wave ratio protection and sending and receiving time sequence...
This letter proposes a dual-resonance CMOS LC-tank injection locked frequency doubler (ILFD) fabricated in the 0.18 μm CMOS process and describes the circuit design, operation principle and measurement results of the ILFD. The ILFD circuit is composed of a RLC dual-resonance first-harmonic injection-locked oscillator (ILO), a wide-band frequency doubler with differential-injection ports. The ILFD...
This paper proposes a systematic procedure in order to make an optimal comparison/selection of modulation techniques and output LCR filter components for adjustable speed drives. Useful indicators are identified, which may help the designer to a global solution, optimizing the modulation-filter selection. The procedure is applied into the design of a real 6.6 kV equipment.
A generalized frequency converter has been realized which makes use of a cyclo-converter in newer form AC-AC converter. An attempt has been made to operate this converter both in a conventional low frequency AC-AC converter and a new high frequency AC-AC converter. The ability to directly affect the frequency conversion of power without any intermediate stage involving DC power is a huge advantage...
Broadband wireless transmission with tunable 5–40GHz carrier is demonstrated using photonic frequency conversion. The agile tuner allows ∼4 GHz of instantaneous bandwidth for both up- and down-conversion paths, without banding or channelization.
In order to extract the fault features of rolling bearing effectively, a new improved enhanced kurtogram method is proposed. Improved enhanced kurtogram is calculated based on harmonic wavelet packet composition and the node whose kurtosis value is maximum is selected after calculating the improved enhanced kurtogram of the original fault signal, then reconstruct the signal through the harmonic wavelet...
We propose a new paradigm of transparent, flexible, and self-powered radio-frequency (RF) harmonic sensor based on all-graphene antenna and frequency multiplier/sensor. The multilayered-graphene antenna receives fundamental tone at C band and retransmits the sensed signal (harmonic tone) at X band, thus allowing high-performance sensing in a severe interference/clutter background. The frequency multiplier...
In the past decade, the use of wind turbines connected to distribution networks, in order to improve voltage profile, reduce losses and increase reliability and network security have been increasing. Meanwhile, the role of static converters and power electronic devices in connecting and controlling the wind turbine power is important. In order to generate the maximum power, decrease the mechanical...
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