Design of Control Strategy and Effect Evaluation for Primary Frequency Regulation of Wind Storage System

Because of wind sources’ volatility and intermittent news, wind power has made a more and more heavy burden on the power system. This paper analyzes in detail the traditional control method, parallel control strategy and serial control strategy of the wind storage system, and combines the advantages of the two to propose an optimal control strategy. A comprehensive performance evaluation method for the primary frequency regulation of the ESS participating in the power grid is proposed based on the power system operation requirements. In the example, the frequency modulation performance of the optimal control strategy is verified by the evaluation method described in this paper in the Chinese frequency adjustment market.

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Lithium battery loss model and economic optimal control strategy for secondary frequency regulation in power system

Journal of Physics Conference Series ◽

10.1088/1742-6596/2108/1/012060 ◽

2021 ◽

Vol 2108 (1) ◽

pp. 012060

Author(s):

XiaoChi Zhang ◽

Xu Sha ◽

ZhiTong Zheng ◽

Jie Gong ◽

Yuan Li ◽

...

Keyword(s):

Optimal Control ◽

Power System ◽

Control Strategy ◽

Lithium Battery ◽

Estimation Method ◽

Variable Parameter ◽

Frequency Regulation ◽

Optimal Control Strategy ◽

Loss Model ◽

Soc Estimation

Abstract Lithium battery energy storage system (ESS) has fast response speed, but it is in service for a long time. Therefore, in the research of secondary frequency regulation, it is necessary to establish a battery model that can reflect the short-term polarization and estimate SOC accurately under long-term service. Therefore, we propose a method of variable parameter loss model of lithium battery suitable for secondary frequency modulation of power system and optimize its control strategy based on the relationship between the independent variable SOC and the internal electrical parameters of the battery. Firstly, we discretize the state equation of single cell to obtain the PNGV model with variable parameters. Then the SOC estimation method is improved by using the modified extended Kalman filter method. Finally, we did an analysis about the economy of the ESS participating in secondary frequency regulation by using the loss model, and the optimal control strategy is designed. The HPPC experiment of the ESS unit is designed by Simulink, and the accuracy of the simulation and experimental curves has been analyzed. Finally, the economic differences between the traditional control strategy and the optimal control strategy considering loss are compared. The results show that the error of the variable parameter model in the fitting experiment is no more than 0.41%, and the accuracy of SOC estimation is 12.96% higher than that of the traditional estimation. The economy of the optimized control strategy is 15.38% higher than that of the traditional control strategy.

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Semi-Active Direct Velocity Control Method of Dynamic Response of Spatial Reticulated Structures Based on MR Dampers

Advances in Structural Engineering ◽

10.1260/136943309789508465 ◽

2009 ◽

Vol 12 (4) ◽

pp. 547-558 ◽

Cited By ~ 2

Author(s):

Yan Bao ◽

Cheng Huang ◽

Dai Zhou ◽

Yao-Jun Zhao

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Control Method ◽

Optimal Placement ◽

Feedback Gain ◽

Control Force ◽

Optimal Control Strategy ◽

Integrated Method ◽

Mr Dampers ◽

Set Up

In this paper, a semi-active optimal control strategy for spatial reticulated structures (SRS) with MR dampers subjected to dynamic actions was proposed. The motion equation of SRS embedded with MR dampers was set up. The performance function of the optimal control strategy including both the structural responses and the control efforts was constituted for the optimization of feedback gain and MR damper placement in SRS, and an integrated method of genetic-gradient based algorithm was developed to solve this optimization problem. The clipped-optimal semi-active control strategy in the conjunction of velocity output feedback was applied to compute the desired control force from the MR dampers. Finally, a numerical example of SRS dealing with optimal placement of MR dampers and feedback gains of control system demonstrates the validity of the present semi-active optimal control strategy.

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Energy Optimal Control Strategy of PHEV Based on PMP Algorithm

Journal of Control Science and Engineering ◽

10.1155/2017/6183729 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11

Author(s):

Tiezhou Wu ◽

Yi Ding ◽

Yushan Xu

Keyword(s):

Optimal Control ◽

Energy Storage ◽

Control Strategy ◽

Hybrid Electric Vehicle ◽

Storage System ◽

Lithium Ion ◽

Energy Storage System ◽

Optimal Control Strategy ◽

Hybrid Energy ◽

Hybrid Energy Storage

Under the global voice of “energy saving” and the current boom in the development of energy storage technology at home and abroad, energy optimal control of the whole hybrid electric vehicle power system, as one of the core technologies of electric vehicles, is bound to become a hot target of “clean energy” vehicle development and research. This paper considers the constraints to the performance of energy storage system in Parallel Hybrid Electric Vehicle (PHEV), from which lithium-ion battery frequently charges/discharges, PHEV largely consumes energy of fuel, and their are difficulty in energy recovery and other issues in a single cycle; the research uses lithium-ion battery combined with super-capacitor (SC), which is hybrid energy storage system (Li-SC HESS), working together with internal combustion engine (ICE) to drive PHEV. Combined with PSO-PI controller and Li-SC HESS internal power limited management approach, the research proposes the PHEV energy optimal control strategy. It is based on revised Pontryagin’s minimum principle (PMP) algorithm, which establishes the PHEV vehicle simulation model through ADVISOR software and verifies the effectiveness and feasibility. Finally, the results show that the energy optimization control strategy can improve the instantaneity of tracking PHEV minimum fuel consumption track, implement energy saving, and prolong the life of lithium-ion batteries and thereby can improve hybrid energy storage system performance.

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Optimal control strategy for PMSG wind power system to restrain the oscillation of dc voltage and transmission power under asymmetrical grid fault

International Conference on Renewable Power Generation (RPG 2015) ◽

10.1049/cp.2015.0480 ◽

2015 ◽

Author(s):

Dan Wang ◽

Chongru Liu ◽

Gengyin Li

Keyword(s):

Optimal Control ◽

Power System ◽

Wind Power ◽

Control Strategy ◽

Transmission Power ◽

Optimal Control Strategy ◽

Dc Voltage ◽

Wind Power System

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A United Control Strategy of Photovoltaic-Battery Energy Storage System Based on Voltage-Frequency Controlled VSG

Electronics ◽

10.3390/electronics10172047 ◽

2021 ◽

Vol 10 (17) ◽

pp. 2047

Author(s):

Xiangwu Yan ◽

Chenguang Wang ◽

Ziheng Wang ◽

Hongbin Ma ◽

Baixue Liang ◽

...

Keyword(s):

Energy Storage ◽

Control Strategy ◽

Control Method ◽

Storage System ◽

Energy Storage System ◽

Control Mode ◽

Battery Energy Storage ◽

Voltage Frequency ◽

Battery Energy ◽

Primary Frequency

At present, the installed capacity of photovoltaic-battery energy storage systems (PV-BESs) is rapidly increasing. In the traditional control method, the PV-BES needs to switch the control mode between off-grid and grid-connected states. Thus, the traditional control mode reduces the reliability of the system. In addition, if the system is accidentally disconnected from the grid or the energy storage battery fails to work normally, the DC voltage of the inverter increases or decreases rapidly. To address these two problems, in this paper, a united control strategy is proposed. In the case of grid connection, based on the voltage-frequency controlled VSG strategy, the strategy adjusts the output power of the VSG by changing the position of the primary frequency modulation curve. This method can ensure that, after the system is connected to the grid, excess PV power can be sent to the grid, or power can be absorbed from the grid to charge energy storage. In the off-grid state, the strategy uses FPPT technology and superimposes a voltage component onto the voltage loop to quickly balance the DC power and AC power of the inverter. This strategy can improve the reliability of the system’s power supply if the energy storage fails to work normally. Finally, a PV-BES model was built using MATLAB-Simulink, and the simulation results proved the effectiveness of the proposed strategy.

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