Zechun Hu

Zechun Hu

Tsinghua University

H-index: 61

Asia-China

About Zechun Hu

Zechun Hu, With an exceptional h-index of 61 and a recent h-index of 49 (since 2020), a distinguished researcher at Tsinghua University, specializes in the field of smart grid, power system, electric vehicle, energy storage.

His recent articles reflect a diverse array of research interests and contributions to the field:

A Novel Electric Vehicle Aggregator Bidding Method in Electricity Markets Considering the Coupling of Cross-day Charging Flexibility

Optimal pricing strategies for distribution system operator in coupled power-transportation system

Flexibility Pricing in Distribution Systems: A Direct Method Aligned with Flexibility Models

Sustainable plug-in electric vehicle integration into power systems

Multiple Joint Chance Constraints Approximation for Uncertainty Modeling in Dispatch Problems

DC-based security constraints formulation: A perspective of primal-dual interior point method

UAV Charging Station Planning and Route Optimization Considering Stochastic Delivery Demand

A decentralized bi-level decomposition method for optimal operation of electric vehicles in coupled urban transportation and power distribution systems

Zechun Hu Information

University

Tsinghua University

Position

___

Citations(all)

11615

Citations(since 2020)

7495

Cited By

7334

hIndex(all)

61

hIndex(since 2020)

49

i10Index(all)

157

i10Index(since 2020)

126

Email

University Profile Page

Tsinghua University

Zechun Hu Skills & Research Interests

smart grid

power system

electric vehicle

energy storage

Top articles of Zechun Hu

A Novel Electric Vehicle Aggregator Bidding Method in Electricity Markets Considering the Coupling of Cross-day Charging Flexibility

Authors

Zhiyuan Bao,Zechun Hu,Asad Mujeeb

Journal

IEEE Transactions on Transportation Electrification

Published Date

2024/1/26

This paper presents a novel method for Electric Vehicle Aggregators (EVAs) to engage in day-ahead and real-time electricity markets, overcoming the issue of cross-day energy gaps of EVAs. Traditional day-ahead bidding processes are usually treated as independent, one-time actions, and fail to consider the continuity of the cross-day energy status of the EV fleet. To tackle this problem, the Endpoint Energy and Power Boundary (EEPB) model is introduced, which is achieved by decomposing each EV charging event into multiple events based on the split points. Then, a two-layer method to determine the optimal split points, i.e., split times and split energy levels, which minimizes the flexibility loss of the EVA, is proposed. Additionally, a novel cross-day bidding method for EVAs, which aligns with the day-by-day bidding process, is proposed. This method utilizes EEPB based on historical EV charging records …

Optimal pricing strategies for distribution system operator in coupled power-transportation system

Authors

Zehan Lu,Ninghui Yang,Yan Cui,Peng Du,Xincheng Tian,Zechun Hu

Journal

Frontiers in Energy Research

Published Date

2024/1/12

The power grid and transportation network are coupled by the charging behavior of electric vehicles. Based on the coupled power-transportation network model, this paper first analyzes the effect of the distribution system operator's (DSO) electricity selling price on guiding the charging behavior of electric vehicles in the transportation network and then builds the DSO's optimal pricing formulation. Considering the competition between multiple charging network operators (CNOs), this paper establishes a game model between CNOs and solves it iteratively through the best response dynamic method. An approximation method using the elasticity matrix is proposed to speed up the solution by reducing the multi-layer optimization to a single layer one in each iteration, with its effectiveness validated through numerical tests. Furthermore, the paper discusses the issue of the prisoner's dilemma that arises among CNOs and explores the potential impact of their cooperative strategies on the overall system.

Flexibility Pricing in Distribution Systems: A Direct Method Aligned with Flexibility Models

Authors

Yilin Wen,Yi Guo,Zechun Hu,Gabriela Hug

Journal

arXiv preprint arXiv:2404.14386

Published Date

2024/4/22

Effective quantification of costs and values of distributed energy resources (DERs) can enhance the power system's utilization of their flexibility. This paper studies the flexibility pricing of DERs in distribution systems. We first propose a flexibility cost formulation based on adjustment ranges in both power and accumulated energy consumption. Compared with traditional power range-based approaches, the proposed method can quantify the potential inconvenience caused to DER users by flexibility activation and directly capture the time-dependent characteristics of DER's flexibility regions. We then propose a flexibility cost formulation aligned with the aggregated flexibility model and design a DSO flexibility market model to activate the aggregated flexibility in the distribution system to participate in the transmission system operation for energy arbitrage and ancillary services provision. Furthermore, we propose the concept of marginal flexibility price for the settlement of the DSO flexibility market, ensuring incentive compatibility, revenue adequacy, and a non-profit distribution system operator. Numerical tests on the IEEE 33-node distribution system verify the proposed methods.

Sustainable plug-in electric vehicle integration into power systems

Authors

Hongcai Zhang,Xiaosong Hu,Zechun Hu,Scott J Moura

Published Date

2024/1

Integrating plug-in electric vehicles (PEVs) into the power and transport sectors can help to reduce global CO2 emissions. This synergy can be achieved with advances in battery technology, charging infrastructures, power grids and their interaction with the environment. In this Review, we survey the latest research trends and technologies for sustainable PEV–power system integration. We first provide the rationale behind addressing the requirements for such integration, followed by an overview of strategies for planning PEV charging infrastructures. Next, we introduce smart PEV charging and discharging technologies for cost-efficient and safe power system operations. We then discuss how PEVs can help to promote clean energy adoption and decarbonize the interconnected power and transport systems. Finally, we outline remaining challenges and provide a forward-looking road map for the sustainable …

Multiple Joint Chance Constraints Approximation for Uncertainty Modeling in Dispatch Problems

Authors

Yilin Wen,Yi Guo,Zechun Hu,Gabriela Hug

Journal

arXiv preprint arXiv:2404.01167

Published Date

2024/4/1

Uncertainty modeling has become increasingly important in power system decision-making. The widely-used tractable uncertainty modeling method-chance constraints with Conditional Value at Risk (CVaR) approximation, can be overconservative and even turn an originally feasible problem into an infeasible one. This paper proposes a new approximation method for multiple joint chance constraints (JCCs) to model the uncertainty in dispatch problems, which solves the conservativeness and potential infeasibility concerns of CVaR. The proposed method is also convenient for controlling the risk levels of different JCCs, which is necessary for power system applications since different resources may be affected by varying degrees of uncertainty or have different importance to the system. We then formulate a data-driven distributionally robust chance-constrained programming model for the power system multiperiod dispatch problem and leverage the proposed approximation method to solve it. In the numerical simulations, two small general examples clearly demonstrate the superiority of the proposed method, and the results of the multiperiod dispatch problem on IEEE test cases verify its practicality.

DC-based security constraints formulation: A perspective of primal-dual interior point method

Authors

Zhiyuan Bao,Yujian Wan,Zechun Hu,Asad Mujeeb

Journal

Electric Power Systems Research

Published Date

2024/3/1

The DC network security constraints have been extensively studied in numerous power system problems, such as optimal power flow (OPF), security-constrained economic dispatch (SCED), and security-constrained unit commitment (SCUC). Power transfer distribution factors (PTDFs) are widely applied in DC network constraints. However, the PTDF matrix is extremely dense, making it difficult to solve security-constraint optimization problems. This paper investigates the computational inefficiency of PTDF-based security constraints from the perspective of matrix sparsity of primal–dual interior point method (IPM), and proposes a matrix transformation to restore sparsity during IPM iterations. It turns out that the transformation method is equivalent to solving the original optimization problem expressed in pure voltage angle. The regular B-θ formulation is also a variant of the proposed transformation. Numerical studies …

UAV Charging Station Planning and Route Optimization Considering Stochastic Delivery Demand

Authors

Zhuoxu Chen,Zechun Hu,Zhiyuan Bao,Wanli Xu

Journal

IEEE Transactions on Transportation Electrification

Published Date

2024/2/2

Unmanned Aerial Vehicle (UAV) cluster is increasingly used in the field of logistics. However, the efficiency of drone delivery is greatly affected by the limited cruising range. Optimal planning charging infrastructure is necessary to expand the service range of drone delivery. In this paper, a comprehensive formulation for optimal siting and sizing of UAV charging stations is built, which is a scenario-based optimization model to minimize the investment cost and task time considering the randomness of delivery demands. The scheme of routing, task allocation, and recharging scheduling is optimized to improve the operational efficiency of the UAV swarm. The spatial topology of drone delivery is constructed, which renders the proposed formulation suitable for complex scenarios with multiple tasks and charging stations. An algorithm combining variable neighborhood search (VNS) with mixed integer linear programming …

A decentralized bi-level decomposition method for optimal operation of electric vehicles in coupled urban transportation and power distribution systems

Authors

Chengcheng Shao,Ke Li,Xuliang Li,Zechun Hu,Mohammad Shahidehpour,Xifan Wang

Journal

IEEE Transactions on Transportation Electrification

Published Date

2023/6/9

The growing prevalence of electric vehicles (EVs) enhances the coupling of urban transportation networks (UTNs) and power distribution networks (PDNs). First, based on the inverse optimization (IO), this paper proposes a holistic pricing framework to manage the power-traffic flows at network equilibrium (NE) towards the least-cost social optimum (SO) state with minimum extra user charges. Second, a coordinated operation model is proposed which assigns the traffic flows and schedules the power generation within grid operation and EV routing and charging constraints. It removes some unrealistic assumptions in existing works. Third, a novel decentralized bi-level decomposition algorithm is designed. It efficiently tackles the computation intractability and preserve the network data privacy by decoupling the UTN and PDN problems in the outer-layer and adaptively generating operation results-aware optimal …

Centralized Distributionally Robust Chance-Constrained Dispatch of Integrated Transmission-Distribution Systems

Authors

Yilin Wen,Zechun Hu,Xiaolu Chen,Zhiyuan Bao,Chunhui Liu

Journal

IEEE Transactions on Power Systems

Published Date

2023/9/22

Coordinated dispatch of integrated transmission-distribution systems (ITDs) continues to be a hotspot due to the growing demand-side flexibility. Decentralized optimization, which has been widely studied, does not conform to the current hierarchical framework of power system operation. This paper proposes a centralized distributionally robust chance-constrained dispatch model for ITDs. The transmission system operator considers the flexible ranges of large-scale distributed energy resources (DERs) in distribution systems via flexibility aggregation. A price-guided flexibility model is proposed to describe the temporally coupled aggregate flexibility of distribution systems. It is constructed by filtering those constraints with a high probability of activeness in the ITD dispatch problem, reducing the number of constraints from quadratic to linear with the number of divided time slots while maintaining high accuracy …

Coordinated Charging and Discharging of Electric Vehicles With Multiple Trips

Authors

Mohsen Ghafouri,Ekram Kabir,Bassam Moussa,Chadi Assi

Journal

ACM Transactions on Cyber-Physical Systems (TCPS)

Published Date

2022/9/7

In this work, we investigate that the abundance of Electric Vehicles (EVs) can be exploited to target the stability of the power grid. Through a cyber attack that compromises a lot of available EVs and their charging infrastructure, we present a realistic coordinated switching attack that initiates inter-area oscillations between different areas of the power grid. The threat model as well as linearized state-space representation of the grid are formulated to illustrate possible consequences of the attack. Two variations of switching attack are considered, namely, switching of EV charging and discharging power into the grid. Moreover, two possible attack strategies are also considered (i) using an insider to reveal the accurate system parameters and (ii) using reconnaissance activities in the absence of the grid parameters. In the former strategy, the system equations are used to compute the required knowledge to launch the …

EV Fast Charging Station Planning Considering Competition Based on Stochastic Dynamic Equilibrium

Authors

Jianzhou Feng,Zechun Hu,Xiaoyu Duan

Journal

IEEE Transactions on Industry Applications

Published Date

2023/1/9

The rapid growth of electric vehicles (EVs) and the deployment of fast charging infrastructures bring considerable impacts on the planning and operation of power systems. Integrating photovoltaic (PV) and energy storage system (ESS) with fast charging station (FCS) can alleviate the negative impacts and bring benefits to both power system operation and charging service provider. In this paper, an integrated procedure is proposed for the charging service provider to optimally plan fast charging stations integrated with PV and ESS in urban area, while taking the influence of its competitors, EV users' decision-making psychology, the uncertainties of charging demand and PV power output into consideration. Firstly, a charging demand estimation method based on average travel speed is presented. Secondly, a stochastic dynamic user choice equilibrium (SDUCE) model and its solution algorithm based on method of …

A Multi-Period Charging Service Pricing Game for Public Charging Network Operators Considering the Dynamics of Coupled Traffic-Power Systems

Authors

Yan Cui,Zechun Hu,Xiaoyu Duan

Journal

IEEE Transactions on Intelligent Transportation Systems

Published Date

2023/5/9

The proliferation of electric vehicles (EVs) couples the operations of traffic systems and power systems, necessitating the interdependent traffic-power modeling to optimize the on-road EV charging decisions. In this paper, the multi-period charging service pricing interactions between multiple charging network operators (CNOs) are discussed considering the dynamics of traffic-power systems. A multi-period user equilibrium model considering mixed vehicle types is formulated to describe the possible vehicle trip transitions between different periods in urban transportation network. For the power distribution network, a convexified multi-period AC optimal power flow model is adopted for local electricity market clearing. With the dynamics of traffic-power systems, the pricing interaction between multiple CNOs is a non-cooperative game. We analyze the existence of Nash Equilibrium with fixed-point theory, and propose an …

Optimal Dispatch Strategy for Power System with Pumped Hydro Power Storage and Battery Storage Considering Peak and Frequency Regulation

Authors

Minjian Cao,Tingting Cai,Zechun Hu

Published Date

2023/8/11

Large-scale new energy access to the power grid provides clean power for the power system, but the uncertainty of new energy output leads to security and stability problems and new energy abandonment in the power system. Pumped storage and battery storage technologies are important means to transfer power and provide power regulation for the system. In this paper, a multi-timescale optimal scheduling model for pumped storage hydropower plants and battery storage systems is developed for large-scale new energy consumption enhancement. The model takes reducing the peak-to-valley difference of the net load curve of the grid and reducing the peaking cost of conventional units as the optimization objectives, and considers the cumulative frequency regulation demand constraints for multiple time periods during the day. By converting the established model into a mixed-integer linear programming (MILP …

Optimal scheduling of pumped storage hydropower plants with multi-type of units in day-ahead electricity market considering water head effects

Authors

Minjian Cao,Zechun Hu,Jilin Cai

Journal

Frontiers in Energy Research

Published Date

2023/11/22

Pumped-storage hydropower plant (PSHP) is a type of valuable energy storage system and a flexible resource to the modern power system with increasing renewable energy integration. As independent market participants, a PSHP can participate in both the energy market and frequency regulation market to maximize its revenue and contribution to the secure and economic operation of the power system. In some PSHPs, both fixed-speed and variable-speed units are installed to improve the flexibility, especially when operating in the pumping mode. However, it’s difficult to deal with the nonlinear relationships among power, flow, and water head in pumping and generating modes. This paper proposes iterative solution methods for scheduling the PSHP by considering the relationship between power and flow at different water heads for different types of units. The scheduling problem is established as a scenario-based optimization formulation by considering PSHP’s participation in both the energy market and frequency regulation market. In each iteration, the optimal dispatch model is formulated as a Mixed Integer Linear Programming (MILP) problem. Case studies are performed and simulation results validate the effectiveness of the model and the iterative solution methods.

The future air quality impact of electric vehicle promotion and coordinated charging in the Beijing-Tianjin-Hebei region

Authors

Yiliang Jiang,Xinyu Liang,Shaojun Zhang,Zechun Hu,Anders Hove,Ye Wu

Journal

Environmental Pollution

Published Date

2023/6/2

The synergetic benefit of air quality improvements together with greenhouse gas (GHG) mitigations from fleet electrification can be maximized if the power used for electric vehicles (EVs) is from renewables. The worth-noting mismatch between renewable power generation and EV fleet charging demand requires appropriate coordination strategy. Here, we analyze the environmental benefits from increased EVs penetration in Beijing-Tianjin-Hebei (BTH) regions by integrating various scenarios of fleet electrification with coordinated charging strategies to examine the air quality improvement and GHG abatement. The study found that fleet electrification could bring substantial reduction on urban PM2.5 in BTH, especially in December by 0.8 ± 0.5 μg/m3. The coordinated charging strategy could further improve the air quality in BTH, albeit smaller than that of fleet electrification itself. PM2.5 reduction benefit from EV …

A Reinforcement learning based coordinated but differentiated load frequency control method with heterogeneous frequency regulation resources

Authors

Yuxin Ma,Zechun Hu,Yonghua Song

Journal

IEEE Transactions on Power Systems

Published Date

2023/3/28

As the diversification of frequency regulation resources, it is increasingly important to find a load frequency control (LFC) scheme that can effectively coordinate different resources. This paper proposes a coordinated but differentiated LFC control method that utilizes heterogeneous frequency regulation resources with their characteristics fully considered. The optimal LFC models for the single area and multi-area power systems are formulated as partially observable Markov decision process model (POMDP) and partially observable Markov game (POMG) considering the accessibility of system information. A deep reinforcement learning method called recurrent proximal policy optimization is leveraged to solve the POMDP and POMG models. Simulations based on historical data demonstrate that the proposed control scheme can better coordinate different resources and achieve superior control performance.

Robust Coordinated Dispatch Strategy for the Power System with Large Offshore Wind Power Integration Under a Typhoon

Authors

Jinhua He,Zechun Hu,Yang Liu,Zhiyuan Bao,Yu Zhu

Published Date

2023/7/7

The installed capacity of offshore wind farms is growing rapidly, especially in recent years with the accelerated development of offshore wind power in China. The regions with more offshore wind power installations are also areas where typhoons are frequent, and the impact of typhoons on the safe and economic operation of offshore wind farms cannot be ignored. This paper proposes a robustly coordinated operation method of the power system with large offshore wind power integration during a typhoon. The method aims to cope with the uncertainty and disruption caused by a typhoon. The method consists of two parts: a model for orderly cut-off and recovery of offshore wind farms that considers typhoon uncertainties, and a two-stage robust optimization model for coordinated dispatch strategy that is solved by column-and-constraint generation (C&CG) algorithm and strong duality theory. The proposed method is …

Cooperation Mode and Operation Strategy for the Union of Thermal Generating Unit and Battery Storage to Improve AGC Performance

Authors

Rui Diao,Zechun Hu,Yonghua Song,Asad Mujeeb,Likai Liu

Journal

IEEE Transactions on Power Systems

Published Date

2023/11

Cooperation Mode and Operation Strategy for the Union of Thermal Generating Unit and Battery Storage to Improve AGC Performance - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Cooperation Mode and Operation Strategy for the Union of Thermal Generating Unit and Battery Storage to Improve AGC Performance Diao, Rui ; Hu, Zechun ; Song, Yonghua ; Mujeeb, Asad ; Liu, Likai Abstract Publication: IEEE Transactions on Power Systems Pub Date: November 2023 DOI: 10.1109/TPWRS.2022.3231044 Bibcode: 2023ITPSy..38.5290D full text sources Publisher | © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project …

Modeling of frequency security constraints and quantification of frequency control reserve capacities for unit commitment

Authors

Likai Liu,Zechun Hu,Yilin Wen,Yuxin Ma

Journal

IEEE Transactions on Power Systems

Published Date

2023/3/6

The high penetration of converter-based renewable energy sources has brought challenges to the power system frequency control. It is essential to consider the frequency security constraints and frequency control reserve requirements in unit commitment (UC). First, a novel extreme learning machine-based method is proposed to approximate the highly nonlinear frequency nadir constraint (FNC) by a set of linear constraints. Second, considering the variation of the frequency insecurity risk under the changing operational condition, we propose to optimize the primary frequency control (PFC) droop gains and reserve capacities in the UC model to provide diverse control efforts in different risk levels adaptively. Third, a secondary frequency control (SFC) reserve capacity quantification method is proposed by combining the Copula theory and distributionally robust optimization technique. The UC simulation is …

Joint Planning of Multi-Type Energy Storages and Flexible Resources for High-Penetration Renewable Energy Integration

Authors

Shaorong Cai,Jianzhou Feng,Peng Zhang,Zechun Hu,Xiaoyu Duan

Published Date

2023/7/7

With the large-scale integration of renewable energy, how to balance the power supply and demand economically and effectively has become an important issue for power systems. Under this circumstance, it is necessary to consider the utilization of flexible resources (FRs) in power system planning. In this paper, a joint planning method of multi-type energy storage systems (ESSs) and flexible resources is proposed, considering the seasonal energy balance of power systems, different balance periods of ESSs as well as the differences of flexibility of FRs among multiple days. Firstly, several typical demand-side flexible resources are modeled, and an aggregate boundary model is adopted to unify the various flexible resources into aggregate feasible region. Then, a planning model for multi-type ESSs and FRs is proposed, which embeds an annual operation simulation of the power system. Energy of ESSs is …

See List of Professors in Zechun Hu University(Tsinghua University)

Zechun Hu FAQs

What is Zechun Hu's h-index at Tsinghua University?

The h-index of Zechun Hu has been 49 since 2020 and 61 in total.

What are Zechun Hu's top articles?

The articles with the titles of

A Novel Electric Vehicle Aggregator Bidding Method in Electricity Markets Considering the Coupling of Cross-day Charging Flexibility

Optimal pricing strategies for distribution system operator in coupled power-transportation system

Flexibility Pricing in Distribution Systems: A Direct Method Aligned with Flexibility Models

Sustainable plug-in electric vehicle integration into power systems

Multiple Joint Chance Constraints Approximation for Uncertainty Modeling in Dispatch Problems

DC-based security constraints formulation: A perspective of primal-dual interior point method

UAV Charging Station Planning and Route Optimization Considering Stochastic Delivery Demand

A decentralized bi-level decomposition method for optimal operation of electric vehicles in coupled urban transportation and power distribution systems

...

are the top articles of Zechun Hu at Tsinghua University.

What are Zechun Hu's research interests?

The research interests of Zechun Hu are: smart grid, power system, electric vehicle, energy storage

What is Zechun Hu's total number of citations?

Zechun Hu has 11,615 citations in total.

What are the co-authors of Zechun Hu?

The co-authors of Zechun Hu are Jianhui Wang, Professor, IEEE Fellow, Pierre Pinson, Scott Moura, Gareth Taylor, Zhiwei Xu, Haocheng Luo.

    Co-Authors

    H-index: 113
    Jianhui Wang, Professor, IEEE Fellow

    Jianhui Wang, Professor, IEEE Fellow

    Southern Methodist University

    H-index: 76
    Pierre Pinson

    Pierre Pinson

    Danmarks Tekniske Universitet

    H-index: 48
    Scott Moura

    Scott Moura

    University of California, Berkeley

    H-index: 37
    Gareth Taylor

    Gareth Taylor

    Brunel University London

    H-index: 25
    Zhiwei Xu

    Zhiwei Xu

    Tsinghua University

    H-index: 11
    Haocheng Luo

    Haocheng Luo

    Tsinghua University

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