An Environmental-Economic Dispatch Method for Smart Microgrids Using VSS_QGA

The increasing penetration of distributed generation resources demands better economic performance of microgrids under the smart-grid era. In this paper, a comprehensive environmental-economic dispatch method for smart microgrids is proposed, with the objective for minimizing the summation of generation and emission costs in the system. As the proposed model belongs to a large-scale nonlinear and nonconvex programming problem, a hybrid heuristic algorithm, named variable step-size chaotic fuzzy quantum genetic algorithm (VSS_QGA), is developed. The algorithm utilizes complementarity among multiple techniques including the variable step size optimization, the rotation mutational angle fuzzy control, and the quantum genetic algorithm and combines them so as to solve problems with superior accuracy and efficiency. The effectiveness of the proposed model is demonstrated through a case study on an actual microgrid system and the advantages in the performance of VSS_QGA is also verified through the comparison with genetic algorithm (GA), the evolutionary programming approach (EP), the quantum genetic algorithm (QGA), and the chaotic quantum genetic algorithm (CQGA)

Research on Thermosensitive Coatings for Thermal Runaway Warning in Energy Storage Power Station

[Introduction] Lithium iron phosphate battery storage power plants are an important basis for new power systems to consume large-scale new energy, however, the thermal runaway of battery cells seriously threatens the operational safety of storage power plants. It is important to conduct real-time monitoring and scientific warning of local overheating in storage power plants. [Method] In this work, a thermal microcapsule with the ability to sense overheating temperature and produce colour changes was prepared and added in appropriate amounts to an epoxy resin matrix to form a composite insulating material with the characteristics of sensing external overheating temperature fields. [Result] Test results show that the colour of the prepared thermosensitive microcapsule/epoxy insulating temperature indication coating can change sensitively with external temperature changes, with a sudden colour change occurring at around 60 °C. When the doping mass fraction of the thermosensitive microcapsules is 0.25%, the insulation strength and dielectric properties of the composite coating are comparable to those of the pure epoxy resin material, maintaining good intrinsic electrical properties. [Conclusion] The thermosensitive colour-changing composite insulation coating proposed in the study can visibly change the temperature of the external local overheating state, providing a new technical route for the application of thermal runaway warning in energy storage power plants, which has certain engineering application value

Case Report: Chronic hepatitis E virus Infection in an individual without evidence for immune deficiency

Chronic hepatitis E virus (HEV) infection occurs mainly in immunosuppressed populations. We describe an investigation of chronic HEV infection of genotype 3a in an individual without evidence for immune deficiency who presented hepatitis with significant HEV viremia and viral shedding. We monitored HEV RNA in plasma and stools, and assessed anti-HEV specific immune responses. The patient was without apparent immunodeficiency based on quantified results of white blood cell, lymphocyte, neutrophilic granulocyte, CD3+ T cell, CD4+ T cell, and CD8+ T cell counts and CD4/CD8 ratio, as well as total serum IgG, IgM, and IgA, which were in the normal range. Despite HEV specific cellular response and strong humoral immunity being observed, viral shedding persisted up to 109 IU/mL. After treatment with ribavirin combined with interferon, the indicators of liver function in the patient returned to normal, accompanied by complete suppression and clearance of HEV. These results indicate that HEV chronicity can also occur in individuals without evidence of immunodeficiency

Assessment Method for Substation Capacity Credit of Generalized Power Source Considering Grid Structure

This paper presents the concept of the generalized power source in an active distribution network. After the energy storage system (ESS), distributed generators (DG), and demand-side controllable load are connected to the active distribution network, part of the system load can be undertaken by these ESS, DG, and controllable load instead of relying on the capacity of the substation, which greatly improves the reliability of the system. The above-mentioned distributed energy resources in the active distribution network are collectively referred to as the generalized power source (GPS). Substation credible capacity refers to the capacity of the GPS to supply the distribution network that is equivalent at the high voltage distribution network level when considering the faults of the main transformer, 110 kV lines, and circuit breakers. Considering the uncertainties and control strategies of GPS, this paper takes a specific distribution area as the background to study its substituted substation capacity. Based on a sequential Monte Carlo evaluation framework and the principle of constant reliability, an evaluation method of the GPS credible capacity is proposed. In order to verify the effectiveness of the method proposed in this paper, the credible capacity of various typical connection modes of a high voltage distribution network is quantitatively analyzed in the case study, which can provide a reference for the capacity planning of an active distribution network substation and grid structure selection

A New Method to Plan the Capacity and Location of Battery Swapping Station for Electric Vehicle Considering Demand Side Management

Compared to electric vehicle (EV) charging mode, battery swapping mode can realize concentrated and orderly charging. Therefore battery swapping stations (BSS) can participate in the demand side management (DSM) as an integrated form. In this context, a new method to plan the capacity and location of BSS for EV, considering DSM, is proposed in this paper. Firstly, based on the original charging power of BSS with the rule of “First-In First-Out”, a bi-level optimal configuration model of BSS, in which net profit of BSS is maximized in the upper model and operating cost of Distribution Company is minimized in the lower model, is developed to decide the rated power, number of batteries, contract pricing and dispatched power of BSS for DSM. Then, the optimal locating model of BSS with the objective of minimizing network loss is built. A mesh adaptive direct search algorithm with YALMIP toolbox is applied to optimize the bi-level model. Simulation calculation was carried on IEEE-33 nodes distribution system and the results show that participating in DSM can improve the economic benefits of both BSS and distribution network and promote the consumption of distributed generation, verifying the feasibility and effectiveness of the proposed method

Optimal Distributed Generator Allocation Method Considering Voltage Control Cost

Up till now, the high penetration of intermittent distributed generation (DG) has posed great challenges to the planning and operation of the grid. To achieve the best balance between economic cost and acceptable capacity of DG, this paper proposes a new integrated planning method of the active distribution network while considering voltage control cost. Firstly, characteristics of decentralized and centralized voltage control methods were analyzed. The technical frameworks, voltage control strategies and economical models of different voltage control systems were put forward. Then, an integrated planning model with objectives to minimize the comprehensive cost and maximize clean energy utilization under the constraint of maintaining acceptable voltage was implemented. Simulations were conducted using the Multi-objective Differential Evolution Algorithm (MODE). IEEE 33-bus test systems were employed to verify the effectiveness of the proposed method. The results demonstrate that the proposed approach is able to connect larger distributed generators and decrease the economic cost of Distribution Network Operators while maintaining voltage within the statutory limits

Expression of an Antiviral Gene GmRUN1 from Soybean Is Regulated via Intron-Mediated Enhancement (IME)

Most of R (resistance) genes encode the protein containing NBS-LRR (nucleotide binding site and leucine-rich repeat) domains. Here, N. benthamiana plants were used for transient expression assays at 3–4 weeks of age. We identified a TNL (TIR-NBS-LRR) encoding gene GmRUN1 that was resistant to both soybean mosaic virus (SMV) and tobacco mosaic virus (TMV). Truncation analysis indicated the importance of all three canonical domains for GmRUN1-mediated antiviral activity. Promoter-GUS analysis showed that GmRUN1 expression is inducible by both salicylic acid (SA) and a transcription factor GmDREB3 via the cis-elements as-1 and ERE (ethylene response element), which are present in its promoter region. Interestingly, GmRUN1 gDNA (genomic DNA) shows higher viral resistance than its cDNA (complementary DNA), indicating the existence of intron-mediated enhancement (IME) for GmRUN1 regulation. We provided evidence that intron2 of GmRUN1 increased the mRNA level of native gene GmRUN1, a soybean antiviral gene SRC7 and also a reporter gene Luciferase, indicating the general transcriptional enhancement of intron2 in different genes. In summary, we identified an antiviral TNL type soybean gene GmRUN1, expression of which was regulated at different layers. The investigation of GmRUN1 gene regulatory network would help to explore the mechanism underlying soybean-SMV interactions

Coordinated Voltage Control of Active Distribution Network

This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG). The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC) controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB

Coordinated Voltage Control of Active Distribution Network

This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG). The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC) controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB

Coordinate Optimization of the Distribution Network Electricity Price, Energy Storage Operation Strategy, and Capacity under a Shared Mechanism

The large scale deployment of renewable generation is generally seen as the most promising option for displacing fossil fuel generators. A challenge in integrating renewable energy resources (RERs) for distribution networks is to find approaches that ensure the long term sustainability and economic profit of the Distribution Company (DisCo). In this paper, considering the air condition load demand side response, a coordinate optimization of the energy storage capacity and operation strategy is presented to maximize the economic profit of the DisCo. The operation strategy in the optimization is divided into two parts. Under the normal state, a price-based air condition quick response strategy is proposed, with both the comfort and economic efficiency of the users taken into account. Under the fault state, a sharing strategy of Generalized Demand Side Resources (GDSRs) is proposed to improve the utilization level of equipment based on the reliability insurance. Finally, the optimization is carried out on an improved IEEE-33 bus test system. The simulation results verify the effectiveness of the proposed method and discuss the effect of the load demand response participation rate on energy storage configuration. At the same time, the effect of GDSRs on the safe load rate of the line is also presented. The research provides a reference for the optimization and utilization of GDSRs