Electricity-Carbon Interactive Optimal Dispatch of Multi-Virtual Power Plant Considering Integrated Demand Response

As new power systems and dual carbon policies develop,virtual power plant cluster(VPPC)provides another reliable way to promote the efficient utilization of energy and solve environmental pollution problems.To solve the coordinated optimal operation and low-carbon economic operation problem in multi-virtual power plant,a multi-virtual power plant(VPP)electricity-carbon interaction optimal scheduling model considering integrated demand response(IDR)is proposed.Firstly,a multi-VPP electricity-carbon interaction framework is established.The interaction of electric energy and carbon quotas can realize energy complementarity,reduce energy waste and promote low-carbon operation.Secondly,in order to coordinate the multiple types of energy and load in VPPC to further achieve low-carbon operation,the IDR mechanism based on the user comprehensive satisfaction(UCS)of electricity,heat as well as hydrogen is designed,which can effectively maintain the UCS in the cluster within a relatively high range.Finally,the unit output scheme is formulated to minimize the total cost of VPPC and the model is solved using theCPLEX solver.The simulation results showthat the proposed method effectively promotes the coordinated operation among multi-VPP,increases the consumption rate of renewable energy sources and the economics of VPPC and reduces carbon emissions.

Response characteristics of plunge pool slabs of Xiaxiluodu Hydropower deformation conditions

The key problem of the energy dissipation scheme of the arch dam body flood discharge and plunge pool below the dam is the stability problem of the plunge pool slab.As the protection structure of the underwater bed,the plunge pool slab bears the continuous impact of high-speed water flow.The hourly average dynamic water pressure on the slab is one of the main loads directly affecting the stability of the slab and is the main factor causing its erosion destruction.After the impoundment of the Xiluodu Hydropower Station,the measuring line of valley width in the plunge pool area has been continuously shrinking.By 2020,the cumulative shrinking value is about 80 mm.In light of the general background condition of valley shrinkage,daily inspection,annual detailed inspection,underwater inspection and drainage inspection of the plunge pool found that the plunge pool has experienced different degrees of damage,which greatly influences the long-term safety stability of the plunge pool.In this paper,the prototype observation data of flood discharge is used as the input load of pulsatingpressure,and the stress and displacement distribution of the plunge pool structure under the vibration load of flood discharge is analyzed under the condition that the stress and strain state of the plunge pool is changed under the influence of valley displacement.The results show that the stress,strain,and displacement distribution of the plunge pool are mainly caused by valley deformation,the vibration caused by flood discharge is little in influence,and the impact effect of deep hole flood discharge tongue on the plunge pool slab is weak.

Long Distance GIL PD Fault Localization Method Based on Amplitude Difference and Time Difference Calculation of UHF Coupling Signal

In the long distance GIL under certain conditions, this paper researches and realizes detection of PD characters and accurate fault localization through UHF coupling sensors at different positions of the GIL pipeline. The main methods for the detection are UHF signal amplitude difference （DOA） and time difference （TOF）. We analyze the localization error by using TE and TEM component and high order TE mode component in electromagnetic coaxial wave guide theory. Research and field test prove the DOA detection error can meet the requirements of real-time online diagnosis and for history tracking analysis. The error of TOF detection method can be controlled within 3% and can be applied to the site.

Cross-Subsidy in Electricity Tariffs in China

With the incessant development of power market reform,the existing cross-subsidy in electricity tariffs has become a critical problem in China's power industry development.On the basis of the theories of cross-subsidy and electricity universal service,the authors take foreign countries' experience as reference to design several solutions to cross-subsidies in electricity tariffs in different phases of China's power industry development.Furthermore,the application and implementation of these solutions are analyzed in this paper.

A Defense Planning Model for a Power System Against Coordinated Cyber-physical Attack

This paper proposes a tri-level defense planning model to defend a power system against a coor-dinated cyber-physical attack(CCPA).The defense plan considers not only the standalone physical attack or the cyber attack,but also coordinated attacks.The defense strategy adopts coordinated generation and transmission expansion planning to defend against the attacks.In the process of modeling,the upper-level plan represents the perspective of the planner,aiming to minimize the critical load shedding of the planning system after the attack.The load resources available to planners are extended to flex-ible loads and critical loads.The middle-level plan is from the viewpoint of the attacker,and aims at generating an optimal CCPA scheme in the light of the planning strategy determined by the upper-level plan to maximize the load shedding caused by the attack.The optimal operational behavior of the operator is described by the lower-level plan,which minimizes the load shedding by defending against the CCPA.The tri-level model is analyzed by the column and constraint generation algorithm,which decomposes the defense model into a master problem and subproblem.Case studies on a modified IEEE RTS-79 system are performed to demonstrate the economic effi-ciency of the proposed model.

Research on remote hydro-generator sets diagnosis system

A type of remote monitoring and diagnosis system is brought forward which based on Matlab Web Server.Firstly,wavelet packet decomposition is introduced to acquire energy features of which reflect hydrogenerator sets performance to be Feature Parameter.Then these Feature Parameters can be adopted as BP Neural Network input variable to realize fault diagnosis.Most of all,it is the first time to adopt Matlab Web Server to hydro-generator sets faults diagnosis field to implement distributed remote monitoring and diagnosis system.Therefore,remote diagnosis application is independent from the OS used on server side.There is no need for software maintenance by clients.And clients can finish remote diagnosis by Web Browser and without installation of Matlab-software.Client users can monitor and diagnose hydro-generator sets by Browser.Finally,further research work is pointed out such as hydro-generator sets fault modeling,accelerating BP Neural Network learning speed and convergence property,improving data transfer speed of Matlab Web Server to meet the needs of real-time diagnosis for hydropower generator sets.

白鹤滩水电站地下厂房通风空调设计探讨

介绍白鹤滩水电站的工程概述,选择白鹤滩气象站数据作为通风空调设计参数。通过对电站的气象条件,地下厂房发热量,壁面传热量及散湿量计算和分析,确定地下厂房各区域通风空调方式,并简要说明地下厂房通风系统,空调系统,防潮除湿措施和冬季、过渡季通风空调措施。

Influence of asymmetric tidal mixing on sediment dynamics in a partially mixed estuary

To investigate the influence of asymmetric tidal mixing(ATM) on sediment dynamics in tidal estuaries, we developed a vertically one-dimensional idealized analytical model, in which the M_2 tidal flow, residual flow and suspended sediment concentration(SSC) are described. Model solutions are obtained in terms of tidallyaveraged, and tidally-varying components(M_2 and M_4) of both hydrodynamics and sediment dynamics. The effect of ATM was considered with a time-varying eddy viscosity and time-varying eddy diffusivity of SSC. For the first time, an analytical solution for SSC variation driven by varying diffusivity could be derived. The model was applied to York River Estuary, where higher(or lower) eddy diffusivity was observed during flood(or ebb) in a previous study. The model results agreed well with the observation in both hydrodynamics and sediment dynamics. The vertical sediment distribution under the influence of ATM was analyzed in terms of the phase lag of the M_2 component of SSC relative to tidal flow. The phase lag increases significantly in estuaries with typical ATM(higher diffusivity during flood and lower diffusivity during ebb) for the case of seaward-directed net bottom shear stress(e.g., strong river discharge). In contrary, the phase lag is reduced by ATM, if the tidally-averaged bottom shear stress is landward(e.g., strong horizontal density gradient). The dynamics of sediment transport was analyzed as a function of ATM phase lag to identify the time of highest sediment diffusivity, as well as a function of the residual flow, to evaluate the relative importance of seaward and landward residual flows. In estuaries with relative strong fresh water discharge or weak tidal forcing(in case of flood season or neap tide), the near bottom SSC could be higher during ebb than during flood, since the bottom shear stress is higher during ebb due to seaward residual flow. However, landward net sediment transport can be expected in these estuaries in case of a typical ATM, because higher diffusivity causes higher SSC and landward transport during the flood period, while both SSC and seaward transport could be lower during ebb. On the contrary, seaward sediment transport can be expected in estuaries with landward tidally mean bottom shear stress in case of a reverse ATM,where sediment diffusivity is higher during the ebb.

High-precision parallel computing model of solute transport based on GPU acceleration

The scenario simulation analysis of water environmental emergencies is very important for risk prevention and control,and emergency response.To quickly and accurately simulate the transport and diffusion process of high-intensity pollutants during sudden environmental water pollution events,in this study,a high-precision pollution transport and diffusion model for unstructured grids based on Compute Unified Device Architecture(CUDA)is proposed.The finite volume method of a total variation diminishing limiter with the Kong proposed r-factor is used to reduce numerical diffusion and oscillation errors in the simulation of pollutants under sharp concentration conditions,and graphics processing unit acceleration technology is used to improve computational efficiency.The advection diffusion process of the model is verified numerically using two benchmark cases,and the efficiency of the model is evaluated using an engineering example.The results demonstrate that the model perform well in the simulation of material transport in the presence of sharp concentration.Additionally,it has high computational efficiency.The acceleration ratio is 46 times the single-thread acceleration effect of the original model.The efficiency of the accelerated model meet the requirements of an engineering application,and the rapid early warning and assessment of water pollution accidents is achieved.

Prediction of bedload transport inside vegetation canopies with natural morphology

Due to vegetation drag and vegetation-generated turbulence,bedload transport in vegetated channels is more complicated than that in nonvegetated channels.It is challenging to obtain accurate predictions of bedload transport in vegetated channels.Previous studies generally used rigid circular cylinders to simulate vegetation,and the impact of plant morphology on bedload transport was typically ignored;these methods deviate from natural scenarios,resulting in prediction errors in transport rates of more than an order of magnitude.This study measured bedload transport rates inside P.australis,A.calamus and T.latifolia canopies and in arrays of rigid cylinders for comparison.The impact of plant morphology on bedload transport in vegetated channels was examined.Inside the canopies of natural morphology,the primary factor driving bedload transport is the near-bed turbulent kinetic energy(TKE),which consists of both bed-generated and vegetation-generated turbulence.A method was proposed to predict the near-bed TKE inside canopies with natural morphology.For the same solid volume fraction of plants,the transport rate inside canopies with a natural morphology is greater than or equal to that within an array of rigid cylinders,depending on the plant shape.This finding indicates that plant morphology has a significant impact on transport rates in vegetated regions and cannot be ignored,which is typical in practice.Four classic bedload transport equations(the Meyer-Peter-Müller,Einstein,Engelund and Dou equations),which are suitable for bare channels(no vegetation),were modified in terms of the near-bed TKE.The predicted near-bed TKE was inserted into these four equations to predict the transport rate in canopies with natural morphology.A comparison of the predictions indicated that the Meyer-Peter-Müller equation had the highest accuracy in predicting the transport rate in vegetated landscapes.

A Low-carbon Operation Optimization Method of ETG-RIES Based on Adaptive Optimization Spiking Neural P Systems

To enhance multi-energy complementarity and foster a low carbon economy of energy resources,this paper proposes an innovative low-carbon operation opti-mization method for electric-thermal-gas regional inte-grated energy systems.To bolster the low-carbon operation capabilities of such systems,a coordinated operation framework is presented that integrates carbon capture devices,power to gas equipment,combined heat and power units,and a multi-energy storage system.To address the challenge of high-dimensional constraint imbalance in the optimization process,a novel low-carbon operation opti-mization method is then proposed.The new method is based on an adaptive single-objective continuous optimiza-tion spiking neural P system,specifically designed for this purpose.Furthermore,simulation models of four typical schemes are established and employed to test and analyze the economy and carbon environmental pollution degree of the proposed system model,as well as the performance of the operation optimization method.Finally,simulation results show that the proposed method not only considers the economic viability of the target integrated energy sys-tem,but also significantly improves the wind power utilization and carbon reduction capabilities.