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To address the decline in system inertia and the risk of frequency instability resulting from high penetration of renewable energy, and to overcome the limitations of centralized control—such as high computational burden and slow response—as well as the lack of global coordination in decentralized control, this study proposes a cooperative decision-making strategy, based on system partitioning, for high-frequency generator tripping control. The method first combines spectral clustering with nodal frequency response correlation analysis to achieve dynamic system partitioning and the selection of characteristic monitoring nodes. A two-layer cooperative architecture consisting of zone controllers and a central controller is then established, in which the zone controllers are responsible for aggregating local information, while the central controller dynamically generates a zonal generator tripping priority sequence based on four indicators: regional power surplus ratio, equivalent inertia, frequency deviation, and Rate of Change of Frequency. A simulation study conducted on an actual provincial power grid in the northwest region with a renewable energy penetration rate of 31.1% showed that compared with the existing decentralized control strategy of the power grid, this method not only achieved better frequency recovery, but also reduced the generator tripping capacity by 6.29%. Compared with advanced centralized strategies, it reduces recovery time by 10% while achieving good frequency recovery. By aggregating regional information to reduce central computing load and implementing coordinated control between regions through a global optimization mechanism, this strategy provides an effective method for high-frequency safety control in power grids with high penetration rates of renewable energy.

A mid-infrared difference frequency generator (DFG) based on a periodically poled thin-film lithium niobate rib waveguide on a sapphire substrate is theoretically studied. A mode analysis is carried out at the mid-infrared region, and the analysis focuses on the effects of waveguide geometry on effective refractive indices of a few lower-order modes. A complete theory suitable for modeling a DFG based on a waveguide structure is described. Its validity is confirmed by comparing the theoretical results with previously reported experimental data. Explicit expressions are presented for nonlinear conversion efficiency, thermal tunability and quasi-phase matching (QPM) bandwidth. The effects of waveguide geometry and mode hybridization on the effective mode field area and mode overlap factor, which are either inversely or linearly proportional to nonlinear conversion efficiency, are studied in detail. In this article, an optimized mid-infrared DFG with improved geometry that exhibits excellent performance, including a higher nonlinear conversion efficiency of 230–273% W−1cm−2 in the temperature range of 20–120 °C; a larger temperature tunability of 2.2 nm/°C; a larger QPM bandwidth of ~130 nm; and a higher idler wave output power, as much as −2 dBm when Pp = 20 dBm and Ps = 11.5 dBm, is suggested.

Abstract Under consideration is the mathematical model of a clock frequency generator in which some high-frequency oscillations of a movable electrode are excited by a sequence of concentrated electrostatic pulses; wherein the times of pulse action are coordinated with the oscillations of the movable electrode by analogy with the well-known theory of a trigger clock. The results of studying the mathematical model provide a fairly complete understanding of the properties of the oscillations that are excited in the generator.

Nonlinear transmission lines (NLTLs) are nonlinear electronic circuits used for parametric amplification and pulse generation, and it is known that left-handed NLTLs support enhanced harmonic generation while suppressing shock wave formation. We show experimentally that in a left-handed NLTL analogue of the Su-Schrieffer-Heeger (SSH) lattice, harmonic generation is greatly increased by the presence of a topological edge state. Previous studies of nonlinear SSH circuits focused on solitonic behaviours at the fundamental harmonic. Here, we show that a topological edge mode at the first harmonic can produce strong propagating higher-harmonic signals, acting as a nonlocal cross-phase nonlinearity. We find maximum third-harmonic signal intensities five times that of a comparable conventional left-handed NLTL, and a 250-fold intensity contrast between topologically nontrivial and trivial configurations. This work advances the fundamental understanding of nonlinear topological states, and may have applications for compact electronic frequency generators. Higher harmonic generation can be enhanced in left-handed nonlinear transmission lines. Here Wang et al. show that the presence of a topological edge state in a circuit analogue of the Su-Schrieffer-Heeger model can increase this enhancement even further.

To address the issues of declining system inertia and insufficient frequency regulation capability caused by high penetration of renewable energy integration into power grids, this paper proposes a distributed multi-type resource coordinated control strategy based on a consensus algorithm. By integrating controllable resources such as distributed photovoltaics (PVs), energy storage, and flexible loads, a frequency response model incorporating multi-type loads is constructed to quantify their dynamic regulation effects on grid frequency. A grouped iterative consensus algorithm is designed to optimize resources by type under communication topology constraints, achieving distributed collaborative updates of state variables to minimize frequency regulation costs while ensuring power balance and output limits. Simulation results based on the IEEE 3-machine 9-node system and a 30-node distribution network demonstrate that the proposed strategy reduces frequency fluctuation peaks and lowers regulation costs compared to traditional fixed-coefficient methods, effectively avoiding risks of high-frequency generator tripping or low-frequency load shedding. The research provides an economical and efficient solution for distributed resource coordination in frequency regulation for power grids with high renewable energy penetration.

Abstract Under consideration is some mathematical model of a clock frequency generator, a device of the MEMS class (microelectromechanical systems). We numerically study the solution of the corresponding second-order ordinary differential equation with nonlinear right-hand side and show that there is a region of the model parameters in which the bounded solutions tend to a stable limit cycle in the phase plane and, therefore, the periodic oscillations are stable with respect to the external perturbations. To determine the boundary of the region, we use the parameter continuation method of the solution of the boundary value problem defining the limit cycle. The model leads to the numerical identification of the region of generator operability.

The plasma produced at 2 MHz radio frequency has substantial energy release stability and can be used to modify a material’s surface. The objective of this research is to create a plasma generator operating at a radio frequency of 2 MHz and examine how voltage affects the plasma spectrum that is generated. An AD9833 frequency generator, a class E amplifier, and impedance matching are used in the design of a 2 MHz radio frequency plasma generator as power amplifiers to create plasma. Variations in voltage, gas, and gas flow have been used. The input voltage variations used were 10V and 15V from the power supply. Two different media, free air (atmospheric gas) and argon gas flow, are used for plasma generation. In free air, the plasma formed is Nitrogen plasma with a wavelength of 300 to 380 nm. Argon gas flow is given a variation of Argon gas rate of 2 LPM, and 3 LPM. The plasma formed is Argon plasma with a wavelength of 700 to 850 nm.

After the fault isolation of the outgoing power grid with a high proportion of new energy, the high-frequency shutdown of the third line of defense is an important control measure to restrain the rise of the frequency of the sending-end power grid. With the increase in the proportion of intermittent power sources such as wind power and photo-voltaic power, the frequency characteristics of the power grid have become more complex. Considering the response characteristics and emergency control capabilities of wind power and photo-voltaic power, this paper proposes a high-frequency ride-through control strategy based on new energy stations. Through coordinated control with high-frequency shutdown measures, the new energy stations can rapidly reduce their power to replace some costly conventional unit operations to achieve more economical frequency safety control, after the high-frequency machine switching round action is executed to avoid over-switching triggering low cycle load shedding when the frequency is reduced to the threshold value, it will trigger the rapid recovery of new energy power generation to meet the requirements of refined frequency stability control of modern power grids. Based on the actual planning of the high-voltage transmission end grid scale, a simulation system was built, and a new energy high-frequency ride-through model was built, which verified the feasibility of the proposed coordinated control scheme for high-frequency switching off with a high-frequency ride-through, and verified the adaptability of the proposed scheme under different operation modes.

By Studying the Principle of Single Side-Band Mixing, a New Method Based on Quadrature Phase Shift for Generating High-Precision Offset Frequency was Proposed. Different Solutions of Precision Quadrature Phase Shift were Designed for Different Frequencies, Including Combining Analog Quadrature Splitter and Wire Delay for 10MHz, Combining Digital Phase Shift Module Using CPLD, Digital Delay Line Chip and Wire Delay for 10kHz. According to the Design Goal, the Design Parameters and Requirements of Narrow-Band Low-Loss Filter were Analyzed. Finally, an Offset Frequency Generator Whose Output Frequency is 9.99999MHz was Developed and an Experiment System is Constructed to Test the Performance of the High-Precision Offset Frequency Generator. According to the Experiment Results, the Following Conclusion can be Drawn that the Allan Deviation of the 9.99999MHz Offset Frequency Generator is 4.03e-13 which is close to the Frequency Stability of 10MHz Signal of Hydrogen Maser MHM-2010 of Sigma Tau Corporation. the High-Precision Offset Frequency Generator can be Used as a Common Source in Dual Mixer Time Difference and as a Reference Signal in Beat Frequency Method.

The ECR2 and ECR3 ion sources at the Argonne Tandem Linac Accelerator System (ATLAS) operate with two microwave frequencies, improving their performance over single frequency operation. A typical method for transmitting both microwave frequencies is by having two separate frequency generators with their own corresponding amplifiers. These amplifiers transmit their microwaves into the ion source using separate waveguides. Another method that is investigated is to combine the low power microwave frequencies with a splitter/combiner and input the combined signals into the high-power amplifier, where the combined signal is amplified and transmitted down a single waveguide into the ion source. These different methods for delivering microwave power with multiple frequencies are compared, focusing on the average charge state and the intensities of each of the charge states for an oxygen plasma produced by the ECR2 ion source. This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357. This research used resources of ANL’s ATLAS facility, which is a DOE Office of Science User Facility.