GRU-integrated constrained soft actor-critic learning enabled fully distributed scheduling strategy for residential virtual power plant

In this study,a novel residential virtual power plant(RVPP)scheduling method that leverages a gate recurrent unit(GRU)-integrated deep reinforcement learning(DRL)algorithm is proposed.In the proposed scheme,the GRU-integrated DRL algorithm guides the RVPP to participate effectively in both the day-ahead and real-time markets,lowering the electricity purchase costs and consumption risks for end-users.The Lagrangian relaxation technique is introduced to transform the constrained Markov decision process(CMDP)into an unconstrained optimization problem,which guarantees that the constraints are strictly satisfied without determining the penalty coefficients.Furthermore,to enhance the scalability of the constrained soft actor-critic(CSAC)-based RVPP scheduling approach,a fully distributed scheduling architecture was designed to enable plug-and-play in the residential distributed energy resources(RDER).Case studies performed on the constructed RVPP scenario validated the performance of the proposed methodology in enhancing the responsiveness of the RDER to power tariffs,balancing the supply and demand of the power grid,and ensuring customer comfort.

Peak Shaving Strategy of Concentrating Solar Power Generation Based on Multi-Time-Scale and Considering Demand Response

According to the multi-time-scale characteristics of power generation and demand-side response(DR)resources,as well as the improvement of prediction accuracy along with the approaching operating point,a rolling peak shaving optimization model consisting of three different time scales has been proposed.The proposed peak shaving optimization model considers not only the generation resources of two different response speeds but also the two different DR resources and determines each unit combination,generation power,and demand response strategy on different time scales so as to participate in the peaking of the power system by taking full advantage of the fast response characteristics of the concentrating solar power(CSP).At the same time,in order to improve the accuracy of the scheduling results,the combination of the day-ahead peak shaving phase with scenario-based stochastic programming can further reduce the influence of wind power prediction errors on scheduling results.The testing results have shown that by optimizing the allocation of scheduling resources in each phase,it can effectively reduce the number of starts and stops of thermal power units and improve the economic efficiency of system operation.The spinning reserve capacity is reduced,and the effectiveness of the peak shaving strategy is verified.

Enhancing Autonomy Capability in Regional Power Grids:A Strategic Planning Approach with Multiple Autonomous Evaluation Indexes

After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network.

Research on the Control Strategy of Micro Wind-Hydrogen Coupled System Based on Wind Power Prediction and Hydrogen Storage System Charging/Discharging Regulation

This paper addresses the micro wind-hydrogen coupled system,aiming to improve the power tracking capability of micro wind farms,the regulation capability of hydrogen storage systems,and to mitigate the volatility of wind power generation.A predictive control strategy for the micro wind-hydrogen coupled system is proposed based on the ultra-short-term wind power prediction,the hydrogen storage state division interval,and the daily scheduled output of wind power generation.The control strategy maximizes the power tracking capability,the regulation capability of the hydrogen storage system,and the fluctuation of the joint output of the wind-hydrogen coupled system as the objective functions,and adaptively optimizes the control coefficients of the hydrogen storage interval and the output parameters of the system by the combined sigmoid function and particle swarm algorithm(sigmoid-PSO).Compared with the real-time control strategy,the proposed predictive control strategy can significantly improve the output tracking capability of the wind-hydrogen coupling system,minimize the gap between the actual output and the predicted output,significantly enhance the regulation capability of the hydrogen storage system,and mitigate the power output fluctuation of the wind-hydrogen integrated system,which has a broad practical application prospect.

Hybrid Satellite-UAV-Terrestrial Maritime Networks:Network Selection for Users on A Vessel Optimized with Transmit Power and UAV Position

The hybrid satellite-UAV-terrestrial maritime networks have shown great promise for broadband coverage at sea.The existing works focused on vessels collaboratively served by UAV-enabled aerial base station(ABSs)and terrestrial base stations(TBSs)deployed along the coast,and proved that data rate could be improved by optimizing transmit power and ABS’s position.In practice,users on a vessel can be collaboratively served by an ABS and a vesselenabled base station(VBS)in different networks.In this case,how to select the network for users on a vessel is still an open issue.In this paper,a TBS and a satellite respectively provide wireless backhaul for the ABS and the VBS.The network selection is jointly optimized with transmit power of ABS and VBS,and ABS’s position for improving data rate of all users.We solve it by finding candidates for network selection and iteratively solving transmit power and ABS’s position for each candidate.Simulation results demonstrate that data rate can be improved by collaborative coverage for users on a vessel.

Model Predictive Control Strategy of Multi-Port Interline DC Power Flow Controller

There are issues with flexible DC transmission system such as a lack of control freedom over power flow.In order to tackle these issues,a DC power flow controller(DCPFC)is incorporated into a multi-terminal,flexible DC power grid.In recent years,a multi-port DC power flow controller based on a modular multi-level converter has become a focal point of research due to its simple structure and robust scalability.This work proposes a model predictive control(MPC)strategy for multi-port interline DC power flow controllers in order to improve their steady-state dynamic performance.Initially,the mathematical model of a multi-terminal DC power grid with a multi-port interline DC power flow controller is developed,and the relationship between each regulated variable and control variable is determined;The power flow controller is then discretized,and the cost function and weight factor are built with numerous control objectives.Sub module sorting method and nearest level approximation modulation regulate the power flow controller;Lastly,theMATLAB/Simulink simulation platformis used to verify the correctness of the establishedmathematicalmodel and the control performance of the suggestedMPC strategy.Finally,it is demonstrated that the control strategy possesses the benefits of robust dynamic performance,multiobjective control,and a simple structure.

Reinforcement Learning-Based Energy Management for Hybrid Power Systems:State-of-the-Art Survey,Review,and Perspectives

The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power systems.Additionally,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational technology.First of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a timeline.Then,the comprehensive survey and review are conducted by collecting papers from mainstream academic databases.Enumerating most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research status.Finally,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control.

Power Relations in Older Adults’ Cognitive Interaction in Clinical Setting: A Multimodal Pragmatic Perspective

This study explored the construction of power relations in the cognitive assessment of older adults within the Chinese clinical context.Data is derived from audio and video recordings that nine older adults produced in the cognitive assessment of the Chinese version of the Montreal Cognitive Assessment-Basic(MoCA-B),which were then annotated and analyzed from a multimodal pragmatic perspective.The study reveals that examiners and older adults employed various speech acts to achieve distinct communicative goals,with power relations between them being reflected through these speech acts.Examiners tend to claim high power,utilizing discourse strategies such as request,interruption,evaluation,rhetorical questions,and directive speech acts.In contrast,older adults assert high power through directive speech acts,rhetorical questions,and interruptions.Both parties also exhibit low power by using confirming questions and explanations.Additionally,gestures,smiles,prosody features,and other non-verbal communicative resources are synergistically employed to exercise power.The interactive mechanism of constructing power relations reveals that age affects older adults’power relations construction even in a professional setting of the Chinese context.The negotiation between the advanced age of older adults and the expertise of examiners jointly shapes power relations in their interactions.

Historical Enlightenment of the Development of Traditional Maritime Powers in the World

In the rise process of the western powers,the ocean undoubtedly plays a very important role. It has become a universal " iron law" in the development history of the world powers to rise to the sea and fall behind it. It is a pioneering undertaking for China to build a characteristic maritime power,which could not " simply replicate" and " forcibly graft" the customary pattern of the western traditional maritime powers formed in hundreds of years.A number of experiences accumulated by the world's traditional maritime powers in the historical process of " going to the sea" are worth summarizing and learning,and it will give us a lot of historical enlightenment.

基于Simulink的E-Power自卸车发动机控制方法

E-Power作为一种新兴混动技术,能够将发动机运行与车辆驱动解耦,实现能量的高效利用。文章介绍一种E-Power自卸车发动机控制方法,该方案充分考虑发电机的工作效率和电池充放电功率限值的条件,通过Simulink模型搭建发动机控制策略。实车CHTC-D循环试验结果表明,按照该控制方法进行发动机驱动,可以平稳控制发动机起停,起到节油效果。

Financial Strategy during Power System Restructuring

Aiming at the problems of power structure irrationality, lagging of power network behind power source development and high proportion of overdone and small sized units existing currently in power system in China, financial and running strategies are set forth corresponding to power system restructuring.

A review:Modification strategies of nickel-rich layer structure cathode(Ni≥0.8)materials for lithium ion power batteries

Lithium ion power batteries have undoubtedly become one of the most promising rechargeable batteries at present;nonetheless,they still suffer from the challenges such as requirement of even higher energy density and capacity retention.Nickel-rich layer oxides(Ni≥0.8)become ideal cathode materials to achieve the high specific capacity.Integration of optimization of synthesis process and modification of crystal structure to suppress the capacity fading can obviously improve the performance of the lithium ion batteries.This review presents the recent modification strategies of the nickel-rich layered oxide materials.Unlike in previous reviews and related papers,the specific mechanism about each type of the modification strategies is specially discussed in detail,which is mainly about inhibiting the anisotropic lattice strain and adjusting the cation mixing degree to maintain crystal structure.Based on the recent progress,the prospects and challenges of the modified nickel-rich layer cathodes to upgrade the property of lithium ion batteries are also comprehensively analyzed,and the potential applications in the field of plug-in hybrid vehicles and electric vehicles are further discussed.

Analysis and management strategies for the low voltage problems of rural power grid based on the distribution network flow calculation method

For a long time, because of the lack of investment capital and enough attentions, the overall constructions of rural power grid were far behind than the urban power grid in Chongqing Jiangbei Power Company. The low voltage problems were highlighted in the rural power grid due to the characteristics of rural power grid. Using the distribution network flow calculation method, we evaluated the low voltage problems of the rural power grid which belongs to Chongqing Jiangbei Power Company. In addition, we collected the data of distribution transformers in electricity consumption peak period. Some practical management strategies were proposed by the analysis and evaluation of potential and appeared low voltage problems.

Data network traffic analysis and optimization strategy of real-time power grid dynamic monitoring system for wide-frequency measurements

The application and development of a wide-area measurement system(WAMS)has enabled many applications and led to several requirements based on dynamic measurement data.Such data are transmitted as big data information flow.To ensure effective transmission of wide-frequency electrical information by the communication protocol of a WAMS,this study performs real-time traffic monitoring and analysis of the data network of a power information system,and establishes corresponding network optimization strategies to solve existing transmission problems.This study utilizes the traffic analysis results obtained using the current real-time dynamic monitoring system to design an optimization strategy,covering the optimization in three progressive levels:the underlying communication protocol,source data,and transmission process.Optimization of the system structure and scheduling optimization of data information are validated to be feasible and practical via tests.

Views from Maritime Education and Training on the Full Implementation of 2010 STCW Amendments

The full review of The International Convention on Standards of Training, Certification and Watch keeping for Seafarers （the STCW Convention） has been accomplished by International Maritime Organization （IMO） and the new amendment, which is also named as Manila amendment, has been effective since 2012, with a transitional period of 2012-2017. Based on the system engineering context consisting of ＂Human, Machine and Environment＂, human factors at sea, i.e., those factors relevant to the seafarers, are consistently underlined. STCW convention is the unique but systematic international maritime legislation looking after the ＂professional competency standards＂ of seafarers. The amendment thereto is of great significance for the Maritime Education and Training （MET） systems, which should be fully understood so as to respond to it effectively. The paper analyzes major impacts brought by the amendment, with purposes to raise recommendations for MET systems to implement the amendment effectively.

China's Global Energy Strategy: from Energy Strength to Energy Power

Since the founding of the People's Republic of China in 1949, China's global energy strategy has experienced three stages: "infancy", "growth" and "maturity". Chinese foreign energy cooperation has also gone through three periods chronologically, which include(1) the period when China got rid of its high dependence on oil imports from the Soviet Union, achieved self-reliance and even became a net exporter;(2) the period when China first focused on "bringing in" and then turned itself into a net importer of crude oil and refined oil; and(3) the period when China "went global" to engage in energy cooperation in diverse areas, gradually shifting into a leading role before launching the Belt and Road Initiative, which marked the full establishment of the Chinese global energy strategy. The objective of the Chinese global energy strategy has gradually changed from merely pursuing "energy strength" to transforming "energy strength" into "energy power"; the mission is mainly to "promote energy cooperation and energy revolution"; to implement this mission, China will provide international public goods to global and regional energy governance through energy diplomacy and services; and the areas covered by the strategy are countries and regions along the "Silk Road Economic Belt".

Exploitation of Renewable Energy—A Strategic Choice for Sustainable Development of Power Industry

Since China is being faced with the pressure of energy shortage and environmental conservation, the power industry in China has to actively develop the renewable energy for electricity generation while raising the utilization efficiency of conventional energy. In view of such facts, China Guodian Corporation decided on a development strategy of giving priority to green power, such as wind power. Based on the national planning of wind power development, the corporation set out its own target of installing wind power capacity of 1500 MW by the end of 2010, and is adopting appropriate measures including promoting the localization of wind turbines and developing hydropower, thermal power and wind power simultaneously. Moreover, it put some relevant suggestions.

Analysis on the Mode and Competitive Strategy of Electricity Sales in the Background of Electric Power System Reform

A new round of reform of the power system conforms to the national development of the energy revolution and the reform of the electricity market system. As an important promoter of the energy revolution and power reform, a new round of power system reform has brought profound changes to the energy industry and the power industry and the electricity market system has changed dramatically. With the release of the electricity market, market competition intensified. This paper analyzes the competition strategy of electricity sales market, analyzes the characteristics of market participants such as power generation enterprises, power grid enterprises, electricity sales companies and users, and puts forward the corresponding coping strategies to help the market participants to deal with the opportunities and challenges brought by power system reform, provide guidance and reference for the market participants.

Brand Strategy and Japan's Soft Power

The 21st century is the time of brand strategy showing its position and importance in operation of enterprises.Rapid rise of the brand strategy in operation and management of enterprises has profound social and operation background.The development process of brand strategy also reflects evolution of market economy.A country's cultural influence power depends on its brand equity.An essential task of brand promotion for a county is to narrow the gap between original image and target image,change the past or one-sided image of the public to products of the country,and implement effective communication and propaganda with the aid of related resource system in the country's soft power,and accept new excellent image.Fundamentally,lifting national soft power is to set up distinct and charming national brand or national image.The influence power with culture and communication as core is the direct manifestation of a country's core competitiveness.Brand is an outstanding feature of a country's strength.Brand stretching can promote liftoff of national economy.In expanding international market,famous brands will play a more and more important role.

China’s Maritime Public Diplomacy from the Perspective of the Maritime Community with a Shared Future

Maritime public diplomacy is needed to assist in implementing China’s maritime power strategy and joint construction of the 21st Century Maritime Silk Road.As a part of major country diplomacy with Chinese characteristics in the new era,China’s maritime public diplomacy follows the concept of building the maritime community with a shared future,and aims to explain China’s maritime strategy,strengthen maritime cooperation,expand the blue circle of friends,spread China’s traditional marine culture,and enhance blue soft power.Since Chinese government departments,coastal cities,central enterprises,mainstream media,and think tanks are politically reliable and can easily coordinate with each other,a"five in one"layout of maritime public diplomacy could allow them work together in the maritime field.