LOW VOLTAGE APPARATUS

Comparative Analysis of China’s Energy Storage Policies During the 14th Five Year Plan Period

SU Tao

2024, 0(11): 1-9. doi:10.16628/j.cnki.2095-8188.2024.11.001

Asbtract ( 143 )

HTML ( 10)

PDF (973KB) ( 67 )

Figures and Tables | References | Related Articles | Metrics

Energy storage technology refers to the technological means used to store energy.During the 14th Five Year Plan period,the installed capacity of new energy generation in China continued to grow,and energy storage developed rapidly.In order to ensure the healthy and rapid development of energy storage technology,the national and local governments have successively introduced more than 100 relevant policies.The national policies are taken as the starting point for analysis,the key points of national energy storage policies are summarized,and the energy storage policies and power system development service policies are sorted out in Northeast,Northwest,North China,Central China,and South China.By comparing the differences in energy storage policies in different regions, the demand and development trends of energy storage applications are analyzed under the policy guidance in each region, the future development prospects of China’s energy storage industry are discussed,and the forward development suggestions are put forword.

Research Progress on Active Protection Against Thermal Runaway of High Power Fast Charging Lithium-ion Batteries

LIU Jianchao, GUO Weiwen, LU Deng, YANG Liming, JIANG Caisheng

2024, 0(11): 10-19. doi:10.16628/j.cnki.2095-8188.2024.11.002

Asbtract ( 177 )

HTML ( 7)

PDF (3204KB) ( 115 )

Figures and Tables | References | Related Articles | Metrics

Short cruising range and long charging time of electric vehicles seriously restrict their rapid development.To solve these problems,high-power fast charging of electric vehicles has revealed as an attractive strategy.Solving the thermal safety caused by high-power fast charging of lithium-ion batteries is an important prerequisite for supporting the development of fast charging.By summarizing home and abroad literature firstly, the mechanism of high power fast charging and thermal runaway of lithium-ion batteries is clarified.Secondly,starting from the optimization methods,liking fast charging strategy,battery design and manufacturing process,fast charging thermal management,etc.,the research progress of high power fast charging thermal runaway active prevention and control of lithium-ion batteries is stated,which provides the development ideas for thermal runaway prevention and control technology to accelerate the development of high power charging of lithium-ion powered batteries.

Research on Stable Enhancement of Black Start Frequency for Grid Forming Energy Storage System Based on Unbiased Integral Feedback Frequency Control

QU Zhanzhan, YANG Ruohuan, NIU Meng, DU Gaoxian, WANG Huanling, LIU Yating

2024, 0(11): 20-28. doi:10.16628/j.cnki.2095-8188.2024.11.003

Asbtract ( 116 )

HTML ( 1)

PDF (2545KB) ( 56 )

Figures and Tables | References | Related Articles | Metrics

Grid forming (GFM) control can effectively improve the active support ability of energy storage system to the power grid.However,the frequency deviation introduced by frequency modulation characteristic of GFM energy storage system (ESS) will affect the frequency stability during black start process.In some extreme cases,it will lead to frequency instability and black start failure.To improve the frequency stability of GFM-ESS during black start process, an unbiased integral feedback frequency control is proposed.By adding an integral feedback loop to the virtual synchronous generator control loop and changing the system order,the frequency regulation is unbiased and then the control complexity is effectively reduced during the process of black start.Meanwhile,PLL and underlying control strategy switchover are not required.Finally,the control effect and the influence of the change of crucial parameters on the control performance are verified by the simulation,and the correctness and effectiveness of the control strategy are proved.

Modeling and Research on Grid-Forming Energy Storage Based on Vanadium Redox Flow Battery

DOU Yan, WANG Chuanyi, CHEN Zihui, WANG Chen, LI Xin

2024, 0(11): 29-37. doi:10.16628/j.cnki.2095-8188.2024.11.004

Asbtract ( 156 )

HTML ( 4)

PDF (2866KB) ( 73 )

Figures and Tables | References | Related Articles | Metrics

To address the intermittent and unstable issues of high-proportion new energy grid connection and enhance its utilization efficiency,the grid-forming energy storage system based on vanadium redox flow batteries (VRFB) is focused on.The research employs a multi-physics field-coupled VRFB hybrid model to simulate its dynamic operation characteristics comprehensively.Based on this,a flexible charge and discharge control strategy based on the outer loop of the DC bus voltage is designed,and the virtual synchronous generator (VSG) control technology is integrated to achieve precise control of VRFB’s charge and discharge.The effectiveness of the strategy is verified through modeling and simulation in MATLAB/Simulink.The results indicate that this strategy can stabilize the output terminal voltage during long-term discharge and performs outstandingly in photovoltaic/VRFB grid-connected operation,frequency and voltage regulation,and maintaining the stability of the DC bus voltage,which can validate the application potential of VRFB in the field of grid-forming energy storage.

Research on Temperature Inconsistency of New and Aged Mixed Battery Packs

WU Yuhao, CHEN Siwen, GUO Yilong, XING Shiyou, WANG Shuhang, WANG Ruoyu, SUN Jinlei

2024, 0(11): 38-44. doi:10.16628/j.cnki.2095-8188.2024.11.005

Asbtract ( 103 )

HTML ( 2)

PDF (2175KB) ( 42 )

Figures and Tables | References | Related Articles | Metrics

The finite element analysis method is used to construct the lumped parameter model of a 18650 lithium-ion battery pack and the key battery parameters through constant current discharging experiments are obtained.The research on the temperature distribution under the aging inconsistent state of the battery pack is focused on.The results show that the high internal resistance of the aged battery leads to significantly higher maximum temperature than other individual cells in the pack.During discharge at 1 C,the maximum temperature rise of the aged battery reaches 13 K.Additionally,the higher the discharge rate of the battery pack,the greater the impact of aging on the maximum temperature rise and temperature consistency of the battery.When the discharging rate reaches 3 C,the temperature inconsistency within the pack reaches 2.09 K.The research results are of certain significance for designing and optimizing battery thermal management systems.

Remaining Useful Life Prediction of Lithium Batteries Based on ISW and Optimized VMD-LSTM

ZHANG Zhoutong, SHENG Wenjuan

2024, 0(11): 45-57. doi:10.16628/j.cnki.2095-8188.2024.11.006

Asbtract ( 111 )

HTML ( 1)

PDF (3460KB) ( 64 )

Figures and Tables | References | Related Articles | Metrics

Aiming at the problem that the remaining useful life (RUL) of lithium battery is difficult to predict accurately due to the capacity regeneration and the continuous curve fluctuation during capacity decline,a long short-term memory (LSTM) neural network prediction model based on variational mode decomposition (VMD) and improved sliding window (ISW) is proposed.Firstly,VMD is used to decompose the capacity data and distinguish the trend of main degradation and the capacity regeneration.Then,ISW is used to capture the curve fluctuation dynamically to improve the prediction accuracy.Finally,LSTM is used to model.The parameters of LSTM and VMD are optimized using Bayesian optimization (BO).The experiment uses NASA data set and is further verified on CALCE data set.Compared with SW-LSTM and ISW-LSTM models,the results show that the proposed method has smaller prediction error and higher stability,which can effectively eliminate the influence of capacity regeneration and curve fluctuation,and has generalization performance and real-time processing capability.

Multi-Machine Parallel Resonance Suppression Method of 125 kW PCS in Grid-Connected Operation Mode Based on Active Damping Control Strategy

WU Shichao, LI Jing, ZHENG Yanbo

2024, 0(11): 58-64. doi:10.16628/j.cnki.2095-8188.2024.11.007

Asbtract ( 136 )

HTML ( 4)

PDF (2250KB) ( 50 )

Figures and Tables | References | Related Articles | Metrics

Based on the popular 125 kW power conversion system (PCS) module in the current market,considering the grid impedance factor,the mathematical modeling and the impedance analysis of a single energy storage PCS and a multi-machine parallel PCS system in the grid-connected operation mode are implemented.The suppression method of multi-machine parallel resonance in the grid-connected operation mode is studied.The system side impedance of multiple PCS parallel systems is analyzed from the point of common connection,and the change of grid-connected current is analyzed by superposition principle.It is found that the coupling between the line impedance of the power grid and PCS is the key to the resonance problem of the system.The harmonic peak suppression of passive damping is analyzed,and an active damping control strategy is proposed to provide virtual damping by optimizing the capacitor current sampling feedback link.Finally,the simulation is carried out by Simulink.The results show that the THD is reduced from 9.67 % to 2.02 % under the grid-connected operation mode of 125 kW PCS multi-machine parallel system with active damping control strategy,and the resonance peak of grid-connected current is well suppressed.

Research on Virtual Power Plants Under New Power Systems

YANG Guangming

2024, 0(11): 65-72. doi:10.16628/j.cnki.2095-8188.2024.11.008

Asbtract ( 114 )

HTML ( 3)

PDF (2282KB) ( 57 )

Figures and Tables | References | Related Articles | Metrics

With the promotion of “dual carbon” goals,the power system has undergone profound changes.A large number of flexible resources such as distributed power sources and adjustable loads have characteristics such as diverse types,disordered time,and wide range of points,resulting in insufficient controllability and regulation ability of the power grid.As an important path for China to achieve the “dual carbon” goals,virtual power plants play an important role in solving the problem of clean energy consumption.The diverse resources on the demand side can be widely aggregated and regulated,which achieves the responsive allocation and real-time coordinated control of distributed energy.Firstly,the necessity of constructing virtual power plants is analyzed.Then,the architecture of virtual power plants is designed.Finally,the aggregation and control algorithm of virtual power plants for market transactions is studied.The algorithm validation analysis shows that virtual power plants are of great significance in improving the flexibility of new power systems and ensuring power safety and supply capacity.

Hierarchical Optimal Scheduling of Virtual Power Plants Considering Multiple Flexible Loads

WEI Xiaogang, LI Zhaoze, ZHANG Jihong, WU Zhenkui, ZHANG Zilei

2024, 0(11): 73-81. doi:10.16628/j.cnki.2095-8188.2024.11.009

Asbtract ( 100 )

HTML ( 2)

PDF (2451KB) ( 26 )

Figures and Tables | References | Related Articles | Metrics

To enhance the consumption of high-penetration renewable energy and promote regional decarbonization,a generalized energy storage model for the synthesis of methanol via electrolysis of hydrogen is established to participate in the dispatch of a virtual power plant (VPP).A hierarchical optimization strategy for VPP considering multiple flexible loads is proposed.In the upper-level model,the generalized energy storage tracks the wind and solar power generation and absorbs part of the output.The mid-level model flexibly adjusts the load through time-of-use pricing and incentives.The lower-level model ensures the balance of power supply and demand in VPP through the thermal power units,the generalized energy storage,and the external electricity transactions.The CPLEX commercial solver is used to analyze and solve the proposed model.By comparing multiple VPP schemes,it is demonstrated that the proposed strategy effectively promotes the consumption of renewable energy,enhances the low-carbon benefits of VPP,and provides the important theoretical guidance for engineering practice.

Design and Operation Analysis of Park Light Storage Microgrid

GUO Yinyuan, YU Chao, LI Chunyang, LI Zongyuan, CHEN Zhuo

2024, 0(11): 82-85. doi:10.16628/j.cnki.2095-8188.2024.11.010

Asbtract ( 122 )

HTML ( 4)

PDF (1738KB) ( 39 )

Figures and Tables | References | Related Articles | Metrics

Based on the energy use structure and actual energy use requirements of the park,a set of optical storage microgrid system of the campus is designed.The photovoltaic power generation system is used as the new electric energy supplement in the park,which reduces the energy cost of purchasing electricity from the grid.By configuring the electrochemical energy storage system with a certain capacity,multiple functions such as energy time shift and backup power support of the campus energy use structure are realized.The overall design and subsystem design of microgrid are summarized,and the operation and test of microgrid are introduced.The operation analysis shows that the system can effectively improve the coordination ability of energy supply and demand,promote the consumption of clean energy nearby,meet the diversified energy needs of the park,and have a good application and promotion prospect.

Development of DC Support Device with Super Capacitor Energy Storage and its Application in Film Industry

ZHANG Jindou, CHI Enxian, SHEN Zhiguang, CAO Licheng, ZHANG Xingguang

2024, 0(11): 86-91. doi:10.16628/j.cnki.2095-8188.2024.11.011

Asbtract ( 100 )

HTML ( 3)

PDF (2170KB) ( 32 )

Figures and Tables | References | Related Articles | Metrics

In response to the demand for voltage sag mitigation devices in the film industry,a super capacitor energy storage DC support device is developed.The working principle of the super capacitor energy storage DC support device is introduced,and the design of the main circuit and control system is described in detail.The test waveform is also provided.Through test data and field application results,the problem of equipment downtime caused by sag in film enterprises has been well solved,which meet the requirements of continuous production in the film industry.

Table of Content