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CSEE Journal of power and Energy Systems 2024年第2期10卷 660-671页

作者： Jingyang Yun Zheng Yan Yun Zhou Peichao Zhang Weidong Hu Key laboratory of control of power transmission and Conversion of Ministry of Education Department of Electrical EngineeringShanghai Jiao Tong University

This paper proposes a multi-time collaborative restoration model for integrated electricity-gas distribution sys-tems(IEGDSs)considering multiple resources after extreme weather events.Based on the linearized power flow constraints of the unbalanced electrical distribution system(EDS)and gas distribution system(GDS),this problem can be formulated as a mixed-integer linear programming(MILP)model.To improve the efficiency and veracity of the solution,a rolling optimiza-tion based two-stage method is developed with the first stage solved by a linear approximation model,and the second stage solved by real-time updated rolling optimization.By solving the MILP problem using rolling optimization,the proposed model and solution method achieve efficient and reliable collaborative restoration of IEGDS considering multiple resources and unbal-anced operation characteristics of EDS.The effectiveness of the proposed model and method is validated by using an IEGDS made of a 37-bus unbalanced EDS and 11-node GDS.Index Terms-Electricity-gas system,mix-integer linear programming,power system restoration.

关键词： Electricity-gas system mix-integer linear programming power system restoration

Force Compensation control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian Ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key laboratory of Heavy Machinery fluid power transmission and control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

Resilience-oriented transmission Expansion Planning with Optimal transmission Switching Under Typhoon Weather

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CSEE Journal of power and Energy Systems 2024年第1期10卷 129-138页

作者： Yang Yuan Heng Zhang Haozhong Cheng Zheng Wang Key laboratory of control of power transmission and Conversion Ministry of EducationElectrical Engineering DepartmentShanghai Jiao Tong UniversityShanghaiChina State Grid East China Branch ShanghaiChina

This paper presents resilience-oriented transmission expansion planning(RTEP)with optimal transmission switching(OTS)model under typhoon weather.The proposed model carefully considers the uncertainty of component vulnerability by constructing a typhoon-related box uncertainty set where component failure rate varies within a range closely related with typhoon intensity.Accordingly,a min-max-min model is developed to enhance transmission network resilience,where the upper level minimizes transmission lines investment,the middle level searches for the probability distribution of failure status leading to max worst-case expected load-shedding(WCEL)under typhoon,and the lower level optimizes WCEL by economic dispatch(ED)and OTS.A nested decomposition algorithm based on benders decomposition is developed to solve the model.Case studies of modified IEEE 30-bus and 261-bus system of a Chinese region illustrate that:a)the proposed RTEP method can enhance resilience of transmission network with less investment than widely used RTEP method based on attacker and defender(DAD)model,b)the influence of OTS on RTEP is closely related with contingency severity and system scale and c)the RTEP model can be efficiently solved even in a large-scale system.

关键词： Decomposition algorithm optimal transmission switching resilience transmission expansion planning uncertainty vulnerability

Security-constrained transmission Maintenance Optimization Considering Generation and Operational Risk Costs

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Journal of Modern power Systems and Clean Energy 2024年第3期12卷 767-781页

作者： Dan Xu Zhi Cai Qian Cheng Guodong Huang Jingyang Zhou Junjie Tang Beijing Key laboratory of Research and System Evaluation of power Dispatching Automation Technology China Electric Power Research Institute State Key laboratory of power transmission Equipment & System Security and New Technology Chongqing University

With the large-scale integration of renewable energy, the traditional maintenance arrangement during the load valley period cannot satisfy the transmission demand of renewable energy generation. Simultaneously, in a market-oriented operation mode, the power dispatching control center aims to reduce the overall power purchase cost while ensuring the security of the power system. Therefore, a security-constrained transmission maintenance optimization model considering generation and operational risk costs is proposed herein. This model is built on double-layer optimization framework, where the upper-layer model is used for maintenance and generation planning, and the lowerlayer model is primarily used to address the operational security risk arising from the random prediction error and N-1 transmission failure. Correspondingly, a generation-maintenance iterative algorithm based on a defined cost feedback is included to increase solution efficiency. Generation cost is determined using long-term security-constrained unit commitment, and the operational risk cost is obtained using a double-layer N-1 risk assessment model. An electrical correlation coupling coefficient is proposed for the solution process to avoid maintenance of associated equipment simultaneously, thereby improving model convergence efficiency. The IEEE 118-bus system is used as a test case for illustration, and test results suggest that the proposed model and algorithm can reduce the total cost of transmission maintenance and system operation while effectively improving the solution efficiency of the joint optimization model.

关键词： Maintenance engineering Costs Optimization power systems Renewable energy sources power grids Load modeling

Dynamic Constraint-Driven Event-Triggered control of Strict-Feedback Systems Without Max/Min Values on Irregular Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 569-580页

作者： Zhuwu Shao Yujuan Wang Zeqiang Li Yongduan Song the State Key laboratory of power transmission Equipment&System Security and New Technology and the School of AutomationChongqing UniversityChongqing 400044China IEEE

This work proposes an event-triggered adaptive control approach for a class of uncertain nonlinear systems under irregular constraints.Unlike the constraints considered in most existing papers,here the external irregular constraints are considered and a constraints switching mechanism(CSM)is introduced to circumvent the difficulties arising from irregular output constraints.Based on the CSM,a new class of generalized barrier functions are constructed,which allows the control results to be independent of the maximum and minimum values(MMVs)of constraints and thus extends the existing results.Finally,we proposed a novel dynamic constraint-driven event-triggered strategy(DCDETS),under which the stress on signal transmission is reduced greatly and no constraints are violated by making a dynamic trade-off among system state,external constraints,and inter-execution intervals.It is proved that the system output is driven to close to the reference trajectory and the semi-global stability is guaranteed under the proposed control scheme,regardless of the external irregular output constraints.Simulation also verifies the effectiveness and benefits of the proposed method.

关键词： Adaptive control dynamic constraint-driven event-triggered control irregular output constraints nonlinear strict-feed-back systems

From tunnel boring machine to tunnel boring robot: perspectives on intelligent shield machine and its smart operation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： Yakun ZHANG Guofang GONG Huayong YANG Jianbin LI Liujie JING State Key laboratory of fluid power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha fluid power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual operations.This study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart operation.Firstly,the definition,meaning,contents,and development modes of intelligent shield machines are proposed.The development status of the intelligent shield machine and its smart operation are then presented.After analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is proposed.Challenges and recommendations are given for achieving autonomous operation.This study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

A laser-engraved wearable gait recognition sensor system for exoskeleton robots

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Microsystems & Nanoengineering 2024年第2期10卷 269-277页

作者： Maowen Sun Songya Cui Zezheng Wang Huayu Luo Huayong Yang Xiaoping Ouyang Kaichen Xu State Key laboratory of fluid power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China School of Information and Electrical Engineering Hangzhou City UniversityHangzhou310015China

As a reinforcement technology that improves load-bearing ability and prevents injuries,assisted exoskeleton robots have extensive applications in freight transport and health care.The perception of gait information by such robots is vital for their control.This information is the basis for motion planning in assistive and collaborative functions.Here,a wearable gait recognition sensor system for exoskeleton robots is presented.Pressure sensor arrays based on laser-induced graphene are developed with flexibility and reliability.Multiple sensor units are integrated into an insole to detect real-time pressure at key plantar positions.In addition,the circuit hardware and the algorithm are designed to reinforce the sensor system with the capability of gait recognition.The experimental results show that the accuracy of gait recognition by the proposed system is 99.85%,and the effectiveness of the system is further verified through testing on an exoskeleton robot.

关键词： hardware robot skeleton

Observer-Based Adaptive Robust Precision Motion control of a Multi-Joint Hydraulic Manipulator

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1213-1226页

作者： Zheng Chen Shizhao Zhou Chong Shen Litong Lyu Junhui Zhang Bin Yao State Key laboratory of fluid power and Mechatronic Systems Zhejiang UniversityHangzhou 310027 Ocean College Zhejiang UniversityZhoushan 316021China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050000 State Key laboratory of fluid power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907 USA

Hydraulic manipulators are usually applied in heavy-load and harsh operation tasks.However,when faced with a complex operation,the traditional proportional-integral-derivative(PID)control may not meet requirements for high control performance.Model-based full-state-feedback control is an effective alternative,but the states of a hydraulic manipulator are not always available and reliable in practical applications,particularly the joint angular velocity measurement.Considering that it is not suitable to obtain the velocity signal directly from differentiating of position measurement,the low-pass filtering is commonly used,but it will definitely restrict the closed-loop bandwidth of the whole system.To avoid this problem and realize better control performance,this paper proposes a novel observerbased adaptive robust controller(obARC)for a multi-joint hydraulic manipulator subjected to both parametric uncertainties and the lack of accurate velocity measurement.Specifically,a nonlinear adaptive observer is first designed to handle the lack of velocity measurement with the consideration of parametric uncertainties.Then,the adaptive robust control is developed to compensate for the dynamic uncertainties,and the close-loop system robust stability is theoretically proved under the observation and control errors.Finally,comparative experiments are carried out to show that the designed controller can achieve a performance improvement over the traditional methods,specifically yielding better control accuracy owing to the closed-loop bandwidth breakthrough,which is limited by low-pass filtering in fullstate-feedback control.

关键词： handle Observer filtering

Numerical modeling and experimental investigation of a two-phase sink vortex and its fluid-solid vibration characteristics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 47-62页

作者： Zichao YIN Yesha NI Lin LI Tong WANG Jiafeng WU Zhe LI Dapeng TAN College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310014China State Key laboratory of fluid power and Mechatronic Systems Zhejiang UniversityHangzhou310058China

A sink vortex is a common physical phenomenon in continuous casting,chemical extraction,water conservancy,and other industrial processes,and often causes damage and loss in production.Therefore,the real-time monitoring of the sink vortex state is important for improving industrial production efficiency.However,its suction-extraction phenomenon and shock vibration characteristics in the course of its formation are complex mechanical dynamic factors for flow field state monitoring.To address this issue,we set up a multi-physics model using the level set method(LSM)for a free sink vortex to study the two-phase interaction mechanism.Then,a fluid–solid coupling dynamic model was deduced to investigate the shock vibration characteristics and reveal the transition mechanism of the critical flow state.The numerical results show that the coupling energy shock induces a pressure oscillation phenomenon,which appears to be a transient enhancement of vibration at the vortex penetration state.The central part of the transient enhancement signal is a high-frequency signal.Based on the dynamic coupling model,an experimental observation platform was established to verify the accuracy of the numerical results.The water-model experiment results were accordant with the numerical results.The above results provide a reference for fluid state recognition and active vortex control for industrial monitoring systems,such as those in aerospace pipe transport,hydropower generation,and microfluidic devices.

关键词： Free sink vortex fluid-solid coupling Level set method(LSM) Multi-physics model Vibration characteristics

Study on Sealing Characteristics of Sliding Seal Assembly of Aircraft Hydraulic Actuator

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Instrumentation 2024年第1期11卷 18-29页

作者： Weinan Li Saixin Shi Hongxia Tang Liang Chen Jiawei Zhang Hao Tang Jianhua Zhao Shijiazhuang Haishan Industrial Development Corporation Shijiazhuang 050200 China Heavy Machinery fluid power transmission and control laboratory Yanshan UniversityQinhuangdao 066004China

The hydraulic actuator,known as the"muscle"of military aircraft,is responsible for flight attitude adjustment,trajectory control,braking turn,landing gear retracting and other actions,which directly affect its flight efficiency and safety.However,the sealing assembly often has the situation of over-aberrant aperture fit clearance or critical over-aberrant clearance,which increases the failure probability and degree of movable seal failure,and directly affects the flight efficiency and safety of military aircraft.In this paper,the simulation model of hydraulic actuator seal combination is established by ANSYS software,and the sealing principle is described.The change curve of contact width and contact pressure of combination seal under the action of high-pressure fluid is drawn.The effects of different oil pressure,fit clearance and other parameters on the sealing performance are analyzed.Finally,the accelerated life test of sliding seal components is carried out on the hydraulic actuator accelerated life test rig,and the surface morphology is compared and analyzed.The research shows that the O-ring is the main sealing element and the role of the check ring is to protect and support the O-ring to prevent damage caused by squeezing into the fit clearance,so the check ring bears a large load and is prone to shear failure.Excessive fit clearance is the main factor affecting the damage of the check ring,and the damage parts are mainly concentrated at the edge of the sealing surface.This paper provides a theoretical basis for the design of hydraulic actuator and the improvement of sealing performance.

关键词： hydraulic actuator contact stress sealing characteristics maximum shear stress