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Since the discovery of high-temperature superconducting materials in the 1990s, high-temperature superconducting motors have gradually developed. Since the 21st century, high-temperature superconducting motor technology has developed rapidly, and a series of results have been achieved. This article describes in detail the development history of high-temperature superconducting motors in recent years, and introduces the principles of high-temperature superconducting. The structure diagram is shown. Finally, the advantages of the high-temperature superconducting motor are summarized, and its application prospects are analyzed.

This paper introduces the specific application of adjustable reactor, expounds its development history and research trend, and classifies the existing adjustable reactors according to their regulation modes. For various types of adjustable reactors, the working principle is introduced in detail, the structure diagram is given, and some application examples are introduced. Some special types of adjustable reactor are also introduced, such as virtual air gap adjustable reactor, magnetic circuit transfer type adjustable reactor, etc. Then, the performances of various adjustable reactors are compared and analyzed, and their advantages and disadvantages are summarized, and their application prospects are preliminarily evaluated.

Synchronous condenser is a good reactive power compensation equipment in power grid. In recent years, with the development of UHVDC transmission, the characteristics of "Strong HVDC and Weak AC" in the power grid have become more and more obvious, so the demand for reactive power compensation is also increasing. Compared with SVC and SVG, synchronous condenser has a larger reactive power compensation capacity, and its reactive power compensation status is getting higher and higher. The reactive power compensation characteristics of synchronous condenser are determined by the characteristics of its excitation power supply. In this paper, a high and low voltage switching type high-precision excitation power supply is designed, its principle is introduced, and the simulation analysis is carried out in PSIM simulation software. Finally, a 1kW low power device is developed and designed to carry out experimental verification.

Immunoassay in biomedical field has attracted more and more attention, and surface plasmon technology is an effective detection method. Electroluminescent devices are suitable for excitation light source of surface plasma technology because of its low energy consumption and small size. In this paper, a light-emitting chip based on MIS structure is designed, and its electroluminescence principle and its internal electron tunneling principle are studied. Simultaneously, the structure and production process of the chip are proposed. The plasma oscillation frequency of doped silicon and the asymptotic frequency corresponding to the SPP dispersion curve of each interface in each MIS junction are calculated and analyzed, and the relationship between the asymptotic frequency and the wavelength of the light emission spectrum of the device is deduced. Finally, the luminescence spectrum wavelength corresponding to the asymptotic frequency of each interface is obtained, which lays a theoretical foundation for future experiments to verify whether the asymptotic frequency of each interface of the MIS junction is consistent with the peak value of the device luminescence spectrum.

This paper proposed a novel grid-connected inverter filtering method using series APF based on magnetic flux compensation. The fundamental and harmonic currents across the primary side of transformer are detected, respectively, which are controlled separately. The fundamental is reversely injected into the secondary side, while the harmonics are injected in phase. Thus, the primary side shows the characteristic of almost zero impedance to fundamental and a very large impedance to harmonics which is larger than the excitation impedance of the transformer. Therefore, this method can isolate harmonics when the fundamental passes through without loss, and function as a harmonic isolator. Finally, the experiment model was established, which proved the application advantages and better performance in grid connected inverter compared with that of LCL filter.

This paper proposed a series hybrid active power filter (SHAPF) with the function of adjustable impedance. The principle of SHAPF based on magnetic flux compensation is addressed. A linear transformer with air gap and multiple secondary windings is chosen, which are injecting specific currents into multiple secondary windings respectively. The fundamental current of primary winding is detected and function as the initial reference signal. And the initial reference signal would be phase shifted to constitute the second type of current reference signals. The multiple secondary windings are also divided into two types, corresponding to be controlled by the two reference currents, so that the primary winding can almost present short circuit for harmonic currents and continuously variable impedance for fundamental current. Besides, the stability condition is derived and analyzed in detail. The simulation results have verified the effectiveness of the proposed SHAPF with adjustable fundamental impedance.

In this paper, by analyzing the characteristics of nonlinear load intermediate frequency induction furnace in steelworks, a harmonic suppression scheme of high-voltage and large-capacity series hybrid APF(SHAPF) was proposed. Based on the principle of magnetic flux compensation, the SHAPF can make the primary side of transformer present short circuit to the fundamental approximately and show high impedance to the harmonic by detecting the fundamental circuit and the selected harmonic currents, which play a role of harmonic isolator. Selected harmonics injection makes the frequency band of control system better handled, which reduces capacity effectively. Additionally, the SHAPF can isolate the background voltage harmonics. Finally, the experiment proves that the SHAPF can be applied to the intermediate frequency induction furnace, and reduce the capacity of the device and isolate the background harmonics.

We demonstrate the power of Gibbs point process models from the spatial statistics literature when applied to studies of resolved galaxies. We conduct a rigorous analysis of the spatial distributions of objects in the star formation complexes of M33, including giant molecular clouds (GMCs) and young stellar cluster candidates (YSCCs). We choose a hierarchical model structure from GMCs to YSCCs based on the natural formation hierarchy between them. This approach circumvents the limitations of the empirical two-point correlation function analysis by naturally accounting for the inhomogeneity present in the distribution of YSCCs. We also investigate the effects of GMCs' properties on their spatial distributions. We confirm that the distribution of GMCs and YSCCs are highly correlated. We found that the spatial distributions of YSCCs reaches a peak of clustering pattern at ~250 pc scale compared to a Poisson process. This clustering mainly occurs in regions where the galactocentric distance >~4.5 kpc. Furthermore, the galactocentric distance of GMCs and their mass have strong positive effects on the correlation strength between GMCs and YSCCs. We outline some possible implications of these findings for our understanding of the cluster formation process., MNRAS in press; 22 pages

In this paper, a kind of light-emitting tunnel junction composed of three layers of metal–insulator-semiconductor (MIS, Au-Al2O3-Si) is introduced and this structure mainly relies on electron tunneling to excite SPPs. The finite element method is used to calculate the electric field distribution and extinction spectrum of the silver nanorod (AgNR) placed on the metal–insulator-semiconductor tunnel junction (MIS-AgNR). In the simulation, the influence of tunneling current on the strength of SPPs propagating along the metal surface is quantitatively studied by changing the thickness of the insulator layer of the MIS tunnel junction and the bias voltage across it. The AgNR is placed on the tunnel junction, and the gap distance between the gold surface of the MIS structure and the AgNR is changed to qualitatively study the relationship between the extinction characteristics of the AgNR and the gap distance. The study found that the amount of the tunneling current is proportional to the intensity of the SPPs on the metal surface. In the range of 4 nm–20 nm gap distance, the adjustment of the resonance peak position in the 500 nm–700 nm range of the extinction spectrum is realized. As the gap distance increases, the position of the resonant peak in the AgNR extinction spectrum will undergo blue-shift, and at the same time the intensity of the extinction peak will decrease. It is worth noting that the change of the blue-shift displacement is exponentially related to the change of the gap distance.

The filtering performance of series hybrid active power filter (SHAPF) based on fundamental magnetic flux compensation positively correlates with the magnetising impedance of the transformer. However, excessive magnetising impedance will decrease reliability while increasing capacity and costs of the whole system. In order to reduce the magnetising impedance while ensuring the same filtering performance of SHAPF, an improved series active power filter (ISAPF) with fundamental and harmonics magnetic flux hybrid control is presented here. The equivalent impedances to fundamental and harmonics in ISAPF are firstly analysed to explain the principle of ‘harmonic isolation’. Then the range of compensation coefficients is investigated in detail based on the complete control block diagram and the open-loop function of ISAPF. Moreover, stability conditions of an overall system with non-linear loads are deduced. Finally, a set of single-phase prototype with two kinds of special transformer has been constructed; the related experiments results showed that ISAPF can ensure the filtering performance while applying a transformer with smaller capacity, thus resulting in the reduction in capacity and the costs while increasing the reliability.

Power system is gradually developed into a power electronic based power system and exists various power quality problems, which promotes the development of active power filter (APF). APF has developed into a comprehensive power quality conditioner. From the perspective of circuit topology, this paper has a more comprehensive classification of existing APFs, which are divided into parallel type, series type, hybrid type and others. Then, based on the fundamental four types, each APF is reviewed from the perspectives of topology, operating principle, application scenarios, and advantages and disadvantages, which provides a reference for researchers. Finally, the problems of the current industrialized APF have been analyzed by simulation, and other existing problems also have been summarized simply, such as supra-harmonics, background harmonics, multi-function power quality Controller. Moreover, this paper also briefly summarizes the further development trend of APF.

A novel variable reactor is presented in this paper. The principle of the novel variable reactor is simply addressed. The equivalent impedance of primary winding of the transformer will vary with the ratio between the primary and the secondary voltages. For the proposed variable reactor, a novel series power quality controller (SPQC) is developed and its principle is analyzed in detail. The SPQC greatly improves the power utility impedance to harmonics instead of the fundamental and plays the role of isolating the harmonics. Because the novel SPQC is with very high impedance to harmonics, the passive power filter can be reduced. Accordingly, three kinds of reduced single-phase passive power filters are presented. The comparison criterion of reducing passive power filter is described. The SPQC is characterized by perfectly isolating the harmonics, simplified passive power filter design, small rating, and being suitable for two kinds of harmonic sources. The validity of the novel SPQC and excellent filtering characteristic are verified by the experimental results.

SummaryTargeting glycolysis has been considered therapeutically intractable owing to its essential housekeeping role. However, the context-dependent requirement for individual glycolytic steps has not been fully explored. We show that CRISPR-mediated targeting of glycolysis in T cells in mice results in global loss of Th17 cells, whereas deficiency of the glycolytic enzyme glucose phosphate isomerase (Gpi1) selectively eliminates inflammatory encephalitogenic and colitogenic Th17 cells, without substantially affecting homeostatic microbiota-specific Th17 cells. In homeostatic Th17 cells, partial blockade of glycolysis upon Gpi1 inactivation was compensated by pentose phosphate pathway flux and increased mitochondrial respiration. In contrast, inflammatory Th17 cells experience a hypoxic microenvironment known to limit mitochondrial respiration, which is incompatible with loss of Gpi1. Our study suggests that inhibiting glycolysis by targeting Gpi1 could be an effective therapeutic strategy with minimum toxicity for Th17-mediated autoimmune diseases, and, more generally, that metabolic redundancies can be exploited for selective targeting of disease processes.

The intestinal mucosa serves as both a conduit for uptake of food-derived nutrients and microbiome-derived metabolites and as a barrier that prevents tissue invasion by microbes and tempers inflammatory responses to the myriad contents of the lumen. How the intestine coordinates physiological and immune responses to food consumption to optimize nutrient uptake while maintaining barrier functions remains unclear. Here, we describe how a gut neuronal signal triggered by food intake is integrated with intestinal antimicrobial and metabolic responses controlled by type 3 innate lymphoid cells (ILC3)1-3. Food consumption rapidly activates a population of enteric neurons that express vasoactive intestinal peptide (VIP)4. Projections of VIP-producing neurons (VIPergic neurons) in the lamina propria are in close proximity to clusters of ILC3 that selectively express VIP receptor type 2 (VIPR2 or VPAC2). ILC3 production of IL-22, which is up-regulated by commensal microbes such as segmented filamentous bacteria (SFB)5-7, is inhibited upon engagement of VIPR2. As a consequence, there is a reduction in epithelial cell-derived antimicrobial peptide, but enhanced expression of lipid-binding proteins and transporters8. During food consumption, activation of VIPergic neurons thus enhances growth of epithelial-associated SFB and increases lipid absorption. Our results reveal a feeding- and circadian-regulated dynamic intestinal neuro-immune circuit that promotes a trade-off between IL-22-mediated innate immune protection and efficiency of nutrient absorption. Modulation of this pathway may hence be effective for enhancing resistance to enteropathogen2,3,9 and for treatment of metabolic diseases.

The intestinal mucosa serves both as a conduit for the uptake of food-derived nutrients and microbiome-derived metabolites, and as a barrier that prevents tissue invasion by microorganisms and tempers inflammatory responses to the myriad contents of the lumen. How the intestine coordinates physiological and immune responses to food consumption to optimize nutrient uptake while maintaining barrier functions remains unclear. Here we show in mice how a gut neuronal signal triggered by food intake is integrated with intestinal antimicrobial and metabolic responses that are controlled by type-3 innate lymphoid cells (ILC3)1–3. Food consumption rapidly activates a population of enteric neurons that express vasoactive intestinal peptide (VIP)4. Projections of VIP-producing neurons (VIPergic neurons) in the lamina propria are in close proximity to clusters of ILC3 that selectively express VIP receptor type 2 (VIPR2; also known as VPAC2). Production of interleukin (IL)-22 by ILC3, which is upregulated by the presence of commensal microorganisms such as segmented filamentous bacteria5–7, is inhibited upon engagement of VIPR2. As a consequence, levels of antimicrobial peptide derived from epithelial cells are reduced but the expression of lipid-binding proteins and transporters is increased8. During food consumption, the activation of VIPergic neurons thus enhances the growth of segmented filamentous bacteria associated with the epithelium, and increases lipid absorption. Our results reveal a feeding- and circadian-regulated dynamic neuroimmune circuit in the intestine that promotes a trade-off between innate immune protection mediated by IL-22 and the efficiency of nutrient absorption. Modulation of this pathway may therefore be effective for enhancing resistance to enteropathogens2,3,9 and for the treatment of metabolic diseases. Feeding controls a neuroimmune circuit comprising VIP-producing neurons and type-3 innate lymphoid cells that helps to regulate the efficiency of nutrient uptake and IL-22-mediated immune protection in the intestine.

SummaryLymphoid cells that produce IL-17 cytokines protect barrier tissues from pathogenic microbes, but are also prominent effectors of inflammation and autoimmune disease. T-helper (TH17) cells, defined by RORγt-dependent production of IL-17A and IL-17F, exert homeostatic functions in the gut upon microbiota-directed differentiation from naïve CD4+ T cells. In the non-pathogenic setting, their cytokine production is regulated by serum amyloid A proteins (SAA1 and SAA2) secreted by adjacent intestinal epithelial cells. However, TH17 cell behaviors vary markedly according to their environment. Here we show that SAAs additionally direct a pathogenic pro-inflammatory TH17 cell differentiation program, acting directly on T cells in collaboration with STAT3-activating cytokines. Using loss- and gain-of-function mouse models, we show that SAA1, SAA2, and SAA3 have distinct systemic and local functions in promoting TH17-mediated inflammatory diseases. These studies suggest that T cell signaling pathways modulated by the SAAs may be attractive targets for anti-inflammatory therapies.

Lymphoid cells that produce IL-17 cytokines protect barrier tissues from pathogenic microbes, but are also prominent effectors of inflammation and autoimmune disease. T-helper (TH17) cells, defined by RORγt-dependent production of IL-17A and IL-17F, exert homeostatic functions in the gut upon microbiota-directed differentiation from naive CD4+ T cells. In the non-pathogenic setting, their cytokine production is regulated by serum amyloid A proteins (SAA1 and SAA2) secreted by adjacent intestinal epithelial cells. However, TH17 cell behaviors vary markedly according to their environment. Here we show that SAAs additionally direct a pathogenic pro-inflammatory TH17 cell differentiation program, acting directly on T cells in collaboration with STAT3-activating cytokines. Using loss- and gain-of-function mouse models, we show that SAA1, SAA2, and SAA3 have distinct systemic and local functions in promoting TH17-mediated inflammatory diseases. These studies suggest that T cell signaling pathways modulated by the SAAs may be attractive targets for anti-inflammatory therapies.

A novel variable reactor based on transformer is proposed in the paper. In the variable reactor, a transformer with air gap is chosen, and the primary voltage is detected and used as the reference signal. A voltage-sourced inverter is applied to track the reference signal in order to yield a controllable voltage, which is applied across the secondary winding of the transformer. When the secondary-controlled voltage and the primary voltage satisfy a proportional condition, the equivalent impedance of primary winding of the transformer will vary continuously. According to the novel variable reactor, a novel shunt power quality controller is proposed and its principle is analyzed in detail. The shunt power quality controller is characterized by parallel topology and single frequency control. The approaches of decreasing the transformer leakage inductance are addressed. The experimental results verify the validity of the shunt power quality controller.

Summary Targeting glycolysis has been considered therapeutically intractable owing to its essential housekeeping role. However, the context-dependent requirement for individual glycolytic steps has not been fully explored. We show that CRISPR-mediated targeting of glycolysis in T cells in mice results in global loss of Th17 cells, whereas deficiency of the glycolytic enzyme glucose phosphate isomerase (Gpi1) selectively eliminates inflammatory encephalitogenic and colitogenic Th17 cells, without substantially affecting homeostatic microbiota-specific Th17 cells. In homeostatic Th17 cells, partial blockade of glycolysis upon Gpi1 inactivation was compensated by pentose phosphate pathway flux and increased mitochondrial respiration. In contrast, inflammatory Th17 cells experience a hypoxic microenvironment known to limit mitochondrial respiration, which is incompatible with loss of Gpi1. Our study suggests that inhibiting glycolysis by targeting Gpi1 could be an effective therapeutic strategy with minimum toxicity for Th17-mediated autoimmune diseases, and, more generally, that metabolic redundancies can be exploited for selective targeting of disease processes.

The development of distributed new energy and electric car and the characteristic of open-loop design closed-loop operation both increase power imbalance between feeders in distribution networks. SNOP(Soft Normally Open Points) do great job in solving power imbalance problems. The parameters of main circuit have huge influence on performance and stability of SNOP. This paper researches selection principles of important elements in main circuit, and combines with typical scenarios to optimally design circuit parameters. Considering optimization goals and restrictions, we use optimization calculation to get optimal parameters.

The magnetic field, electromagnetic force and electromagnetic torque of a 300 MV A large capacity synchronous condenser were researched in cases of the rotor air-gap eccentricity fault, the rotor dynamic eccentricity fault respectively. Analytical method was selected to analyze the airgap permeance in both static and dynamic eccentricity conditions. The distortion of the air-gap flux density is deduced next. Static and dynamic eccentricity models were established with finite element analysis software and the simulations were conducted later. Fast Fourier Transform was used to extract the harmonics of the magnetic flux density and the electromagnetic force. This result can enrich the diagnostic criteria of air gap eccentric fault on the existing basis, and provide a theoretical basis for synchronous condenser fault monitoring.

This paper reveals a novel saturated iron-core fault current limiter (SICFCL). The novel SICFCL use tightly coupled structure of AC and DC windings to overcome the shortcomings of the traditional loosely coupled structure and to increase the flux transfer efficiency and improve the ratio of current limiting impedance to steady state impedance; Use the cross-parallel structure of four AC windings to eliminate the AC magnetic flux in the DC winding and prevents the AC induction voltage on the DC winding from damaging the DC components. This paper analyzes the working principle and impedance characteristic curve of novel SICFCL and establishes a simulation model of the novel SICFCL based on ANSYS finite element simulation software. The influence of novel SICFCL connected to power grid is analyzed in a typical 10kV application scenario, including the current changes in all kinds of short-circuit fault and the requirement of grid reclosing. The simulation results verify the correctness of the novel SICFCL and provide guidance for the development of the device and connected to actual power grid.

In this paper, a principle of microgrid variable reactor with filtering function using transformer and inverter is proposed to solve the problems of control deviation caused by harmonic pollution in microgrid and the variable reactor's discontinuous adjustment. Firstly, it introduces the principle of variable reactor. A transformer with air gap is chosen and the voltage of the transformer's primary winding is detected and functioned as the reference signal after filtering, phase shift and superposition. A voltage source PWM inverter is applied to produce a voltage source, which follows the reference signal and energizes the secondary winding of the transformer so that the equivalent impedance of primary winding can present a four-quadrant continuously variable impedance to fundamental and infinite impedance to harmonic. The stability condition is also analyzed. The simulation results show the effectiveness and excellent filtering characteristic of the proposed microgrid variable reactor with filtering function.

This paper reveals a kind of adjustable reactor. Firstly, it introduces the basic principle of the reactor. The reactor is based on a transformer with air gap. The current signal of primary side is detected and then directly injected into the secondary side. In this paper, the phase difference(caused by time delay) between the detected current signal of primary winding and the injected current signal of secondary winding is taken into consideration. The effect of phase shift on the equivalent impedance of the reactor is analyzed. And its effect on system stability is also analyzed. The validity of the theory is proved by the simulation results.

According to the requirement of the power factor and the dynamic performance of the asynchronous machine tool field, an asynchronous motor inverter with active power factor correction is proposed. The proposed inverter is a 3kW asynchronous motor drive control platform. At first, the proposed single phase converter with APFC is realized by using the MATLAB/SIMULINK. Then, the boost APFC is designed based on the UC3854. Finally, in rated load conditions, experimental results about the power factor and the dynamic performance highlight the effectiveness of the APFC module.