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With the increasing capacity of wind energy conversion system (WECS), the rotational inertia of wind turbine is becoming larger. And the efficiency of energy conversion is significantly reduced by the large inertia. This paper proposes a novel maximum power point tracking (MPPT) method to enhance the efficiency of energy conversion for large-scale wind turbine. Since improving the efficiency may increase the fluctuations of output power, power smoothing is considered as the second control objective. A T-S fuzzy inference system (FIS) is adapted to reduce the fluctuations according to the volatility of wind speed and accelerated rotor speed by regulating the compensation gain. To verify the effectiveness, stability and good dynamic performance of the new method, mechanism analyses, small signal analyses, and simulation studies are carried out based on doubly-fed induction generator (DFIG) wind turbine, respectively. Study results show that both the response speed and the efficiency of proposed method are increased. In addition, the extra fluctuations of output power caused by the high efficiency are reduced effectively by the proposed method with FIS. [ABSTRACT FROM AUTHOR]

Highlights • Two-level virtual MGC structure is presented to simplify internal power interactions. • The cooperative energy management scheme is proposed based on distributed MPC. • The distributed problem is optimized based on cooperative logarithmic-barrier method. Abstract With the fast development of microgrids (MGs), the microgrid community (MGC) integrating adjacent MGs has raised more and more attentions. In an MGC, each MG shares available power reciprocally to minimize the operation costs and maintain power balance. As the amount of MGs grows, the MGC becomes complicated and difficult to control. Different from centralized strategy, this paper proposes a cooperative energy management scheme based on distributed model predictive control (DMPC) for grid-connected MGC. The normal MGC is virtualized as two-level structure to simplify the internal interactions among subsystems. All the subsystems iterate in parallel adopting the proposed cooperative logarithmic-barrier method, which follows a communication protocol to derive control signals. The real-time hardware-in-the-loop (HIL) study verifies that, the optimization results of proposed DMPC approximate to Pareto solutions of centralized MPC (CMPC), whereas the computing speed is much faster than CMPC. [ABSTRACT FROM AUTHOR]

In this work, a novel bright yellow fluorescent carbon dots (CDs) was synthesized from N-methyl-1,2-phenylenediamine hydrochloride in ethanol solvent through the solvothermal method. The obtained carbon dots had no fluorescence in water, but could specifically light up in the cell which makes the staining process without washing. Interestingly, the imaging process can be performed by simply shaking the culture with the cells for only 1 min, indicating ultrafast and easy to operate fluorescence imaging. Moreover, the carbon dots with abundant amino functional groups had good lysosome targeting properties (the Pearson's correlation coefficient is 0.92) and could achieve the ultrafast lysosome imaging in cell and zebrafish and monitoring cell apoptosis status. This is the first lysosome targeting carbon dots that allows the combination of a short incubation at the second-level with wash-free process providing great potential for continuous observation lysosome in vivo. The obtained carbon dots can not only accumulate in lysosome rapidly by the clathrin-mediated endocytosis and were used for wash-free in lysosome and zebrafish imaging, but also monitor the dynamic change of lysosomal apoptosis. Image 1 • The method has intrinsic lysosome targeting without further modification. • The carbon dots can accumulate in lysosomes within 1 min by the clathrin-mediated endocytosis. • The obtained carbon dots were used for wash-free lysosome imaging in living and fixed cells. • The carbon dots can monitor the dynamic change of lysosomal apoptosis. • The obtained carbon dots were also used for ultrafast and wash-free imaging in zebrafish. [ABSTRACT FROM AUTHOR]

For the existing pitch and torque control of the wind turbine generator system (WTGS), further development on coordinated control is necessary to improve effectiveness for practical applications. In this paper, the WTGS is modeled as a coupling combination of two subsystems: the generator torque control subsystem and blade pitch control subsystem. Then, the pole positions in each control subsystem are adjusted coordinately to evaluate the controller participation and used as the objective of optimization. A two-level parameters-controllers coordinated optimization scheme is proposed and applied to optimize the controller coordination based on the Pareto optimization theory. Three solutions are obtained through optimization, which includes the optimal torque solution, optimal power solution, and satisfactory solution. Detailed comparisons evaluate the performance of the three selected solutions and provide the optimized controller coordination suggestions according to different requirements. [ABSTRACT FROM AUTHOR]

In this paper, a s plit-aptamer m ediated r egenerable t emperature-sensitive (SMRT) electrochemical biosensor was constructed for the detection of exosomes. The split-aptamer used in this SMRT biosensor was composed of two fragments, one of which was immobilized on the surface of an electrode via sulfhydryl groups and named split-a and the other was labelled with methylene blue and named split-b. The two fragments could form sandwich structures at the electrode surface via target-induced self-assembly in the presence of target exosomes at 4 °C in PBS, and then realizing the detection of exosomes via voltammetry. In addition, due to the temperature sensitivity of the split-aptamer, the electrode could be regenerated through temperature-induced disassembly of the sandwich structures. Consequently, the SMRT biosensor realized sensitive and specific analysis of target exosomes with a limit of detection of 1.5 × 106 particles/mL and could be quickly and easily regenerated by washing with PBS at 37 °C for 30 s without any additives. This is the first study on the construction of a reproducible electrochemical biosensor using a split-aptamer for the specific detection of tumour exosomes, and may provide an innovative strategy for the economical and efficient design of regenerable electrochemical biosensors. [Display omitted] • A split-aptamer mediated regenerable temperature-sensitive (SMRT) biosensor was built for the first time. • The sensitive and specific detection of SMMC-7721 exosomes was successful implementation. • The SMRT biosensor could be regenerated simply and quickly by adjusting the temperature to 37 °C in 30 s. [ABSTRACT FROM AUTHOR]