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The answer to global problems challenging energy sector was to use more efficiently local alternative (non-conventional fossil fuel or renewable) energy resources. In power systems, the use of renewable energy (RE) based distributed generation (DG) has increased considerably all over the world; the presence of DG units at distribution voltage level determines the transition from traditional passive...
Developing Energy Internet (EI) proves helpful for building resource-saving and environment-friendly society. However, the widely-used power electronic technology and high percentage of distributed generations (DGs) in EI cause the harmonic problem developed from a local to network issue. Therefore, it is compulsorily necessary to compute the harmonic power flow of the whole EI network. At the same...
Wideband high power generation is an essential and challenging part of many Terahehrtz systems. In this paper we review some of our recent demonstrations of Si/SiGe THz frequency multipliers that generate a wideband high power signal. The proposed design techniques blend the nonlinear modeling of the active device with new circuit topologies and high efficiency microwave structures. In the first prototype,...
Because of the governmental incentives, the distributed photovoltaic systems are populating rapidly in Turkish Electric System. This work aims to evaluate the effects of those plants to the electrical system in terms of voltage quality by focusing on the specific example of the solar plant being built under the National Solar Power Plant Development Project (Milli Günes Enerjisi Santrali Gelistirilmesi...
A high-order-mode harmonic multiplying gyrotron traveling-wave amplifiers (gyro-TWA) with large circuit dimensions and low ohmic loss can achieve a high average power. Wall losses can suppress some competing modes; however, such wall losses do not suppress all competing modes in the gyro-TWA. An improved mode-selective circuit can provide the rejection points within the frequency range to suppress...
This paper presents an adaptive biasing method for step recovery diode based comb generators which are controlled by a software routine. The aim is to provide the maximum possible harmonic output power for a given configuration and different input frequencies during input power variation. This increases the usefulness of comb generators as harmonic phase reference sources for non-linear VNA measurements...
A certain 5th and 7th harmonic voltage in the grid is allowed, which will result in 6 times output power ripple of the grid-connected inverter based on the traditional vector control. In order to enhance adaptive ability for grid-connected inverter, a direct power ripple rejection strategy based on resonant controller is proposed in this paper to achieve smooth output active power and reactive power...
The output power regulation and transfer efficiency are key issues in inductively coupled power transfer system (ICPT) systems. The harmonic based phase shift control (HPSC) is an effective method to improve system efficiency. However, due to the high frequency and harmonic components of the inverter output current within this method, general closed-loop control is not suitable. Meanwhile, in inductively...
In this paper, class F power amplifier covering a wide dynamic range with a steady gain for non-constant envelope signal used in CDMA systems is designed and studied. The design principle is attempted to operate at high values of peak to average power ratio likely to be up to PAPR = 10dB in such systems. The design also takes care of improving the adjacent channels interference ratio (ACPR) of such...
In this paper we report a novel slow wave structure which is evolved from traditional folded wave guide for THz back-ward wave oscillators (BWOs). The back-ward wave impedance of the novel slow wave structure is much higher than traditional folded wave guide, and the PIC simulation results show that the output power can reach 100mW, which is a good candidate of THz for sources for fusion plasma diagnostics.
This paper presents a V-band frequency quadrupler in 0.1-µm SiGe BiCMOS technology with 3-dB bandwidth from 44.8 to 57.2 GHz. The circuit employs cascode stacks comprising in-phase class-C common-emitter and anti-phase class-AB cascode devices to obtain current pulses at ×4 frequency. Four such cascodes driven with differential and tunable quadrature increase the 4th harmonic output power while suppressing...
This paper presents a 38 GHz 2-stage harmonic-tuned power amplifier consisted of a class-F−1 output power amplifier proceeded by a class-AB driving stage in 0.13 µm SiGe BiCMOS technology. In order to shape highly efficient class-F−1 current and voltage waveforms, the PA adopts multi-resonance series and parallel load networks that modulate load impedance to generate an optimum 50-Ω for signal band,...
In this paper, the design of slow wave structures for an X-band broadband TWT with suppression of backward-wave using the helix pitch step method is present. An optimized design of a high-power X-band broadband TWT with improved BWO suppression and forward-wave saturated output power is presented.
This paper presents a fully integrated 6-12 GHz GaN MMIC push-pull amplifier for low harmonic drive applications. A folded Marchand balun is used to perform the unbalanced-balanced and balanced-unbalanced transformations. The three-stage push-pull amplifier provides in excess of 28 dB of small signal gain at a quiescent bias point of 25V, 200mA. The minimum saturated output power across the 6-12 GHz...
In this paper a comparison between a 5 and 6 phases alternator is achieved. The target is to show how the 5-phase structure may influence the alternator performance comparing with a classical 6-phase configuration. Current and voltage harmonics of both 5 and 6 phases alternator provided with a bridge rectifier are analyzed. The impact of the phase current third harmonic on the output power in 5-phase...
The paper presents the stationary frame control strategy for voltage source inverter (VSI) under unbalanced and distorted grid voltage, which aims at the two alternative control targets, namely 1) balanced and sinusoidal three-phase current; 2) the smooth active and reactive power injected into the power grid. Unlike the conventional method, the proposed strategy requires no complicated and time-consuming...
Backward wave oscillation modes in a TE01 Gyro-TWT are researched by a nonlinear theory with consideration of electrons misalign. The results show the output power of most oscillation modes decreases with the increment of misaligns distance.
This paper presents a designe of drive stage power amplifier for the RF transmitting system, which works in the frequency range of 930–960 MHz. The simulation results meet all scheduled design index, power gain is about 15.6 dB, the output power of 1dB compression point is about 26.6 dBm, the return loss of both the input and output ports are excellent, and the output power of driver stage amplifier...
In this paper, models of central-station PV plants, are represented. The detailed and equivalent PV models and area of their applications and limitations for different studies (load flow, short circuit calculation, RMS modeling and harmonic analysis) are proposed. Levels of detailing from one node to in-depth model of PV plant are overviewed.
Increasing concern on pollution and global warming has prompted Photovoltaic (PV) system as one of the potential renewable and clean energy in power system generation. Power quality issue such as Total Harmonic Distortion (THD) has become an increasingly serious concern as more PV is integrated into the grid system. This encourages an extensive study to identify the challenge in power system network...
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