Table of Content

30 July 2021, Volume 0 Issue 7

Previous Issue    Next Issue

Overview

Current Status and Prospect of Energy Storage Technology by Hydrogen Production Based on Water Electrolysis

CONG Lin, WANG Nan, LI Zhiyuan, LI Na, ZHOU Xichao

2021, 0(7):  1-7.  doi:10.16628/j.cnki.2095-8188.2021.07.001

Asbtract ( 516 )   HTML ( 26)   PDF (1263KB) ( 519 )  

Figures and Tables | References | Related Articles | Metrics

The large-scale development and utilization of renewable energy including solar and wind energy promote the development of energy Internet around the world.Energy storage is one of the key technologies in integrated energy systems with a high proportion of renewable energy.With the advantages of long-term energy storage,long transportation distance and abundant ways of consumption and utilization,hydrogen-based energy storage technology by water electrolysis will promote the penetration of renewable energy and play a significant role in the future.In this work,the characteristics of various energy storage technologies are compared.The working principles,characteristics and current applications of various water electrolysis technologies are thoroughly discussed.The development of related hydrogen storage,transportation,and utilization technologies are briefly summarized.Finally,the development trends of hydrogen production by water electrolysis,as well as the hydrogen storage,transportation and utilization technologies are prospected.

Hydrogen Energy Storage Technology

New Energy-Power to Hydrogen Capacity Two-Level Planning

SONG Xinfu, JING Shibo, ZHANG Hong, YUAN Tiejiang

2021, 0(7):  8-13.  doi:10.16628/j.cnki.2095-8188.2021.07.002

Asbtract ( 265 )   HTML ( 5)   PDF (1674KB) ( 213 )  

Figures and Tables | References | Related Articles | Metrics

Take wind power hydrogen production as an example.First,this paper establishes a life-span economic analysis model of the electric hydrogen production system under random fluctuation input.Based on this,three wind power-electric hydrogen production capacity double-level planning models are proposed.The upper models are based on the electric hydrogen production system.The life cycle total cost,investment cost and internal rate of return are used as the objective function of the upper optimization model.The lower optimization target is the curtailment rate of the wind farm,and the constraints are the curtailment rate constraints and the operating constraints of the hydrogen production system,and MATLAB genetics is used.The algorithm toolbox solves the model.Finally,a certain region in Gansu is taken as an example to verify the effectiveness of the proposed bi-level programming model and the economic feasibility of wind power hydrogen production.

Optimal Operation Method of Electric-Hydrogen Integrated Energy System Based on Master-Slave Game

WAN Lixin, LU Limin, LU Huaigu, HAN Yuqian, GE Le

2021, 0(7):  14-22.  doi:10.16628/j.cnki.2095-8188.2021.07.003

Asbtract ( 342 )   HTML ( 4)   PDF (1888KB) ( 276 )  

Figures and Tables | References | Related Articles | Metrics

In order to optimize the overall economic benefit and hydrogen distribution of the electric hydrogen integrated energy system,a master-slave game based optimal operation method and strategy solving algorithm for the electric hydrogen integrated energy system are proposed in this paper.Firstly,the basic architecture of the electric and hydrogen integrated energy system is designed,and the integrated structure of production and marketing is constructed.Secondly,based on the idea of master-slave game,the energy storage behavior and hydrogen sales behavior are regarded as two virtual players of the electric hydrogen integrated energy system operators.The operator was regarded as the leader,and the two virtual players were regarded as the followers.A master-slave game model of one master and two slaves was established.Thirdly,information entropy is introduced into the genetic algorithm to calculate the initial population and design the fitness function,and the model is solved.Finally,the results of an example show that the proposed model can effectively improve the overall economic benefit of the system,and the improved information entropy genetic algorithm has a strong ability of optimization,solution accuracy and stability.

Calculation Method of Rated Power Boundary of Electrolytic Cell Based on Sequential Production Simulation and Air Rejection Rate Constraint

XIE Yongsheng, YANG Yang, JING Shibo, YUAN Tiejiang, XUE Jingjie, WANG Zhengyi

2021, 0(7):  23-28.  doi:10.16628/j.cnki.2095-8188.2021.07.004

Asbtract ( 305 )   HTML ( 2)   PDF (1786KB) ( 198 )  

Figures and Tables | References | Related Articles | Metrics

The reasonable selection of rated power of electrolyzer is the key problem of hydrogen production by wind power.Aiming at this problem,this paper proposes a calculation method of rated power boundary of electrolyzer based on time series production simulation and considering wind rejection rate.Through the relationship between the output and rated power of the electrolytic cell,the air abandonment rate can be calculated by using the time series production simulation,and then the relationship between the rated power and the air abandonment rate of the electrolytic cell can be obtained.The rated power boundary of the electrolytic cell can be calculated by using the air abandonment rate boundary specified by the state.In order to make the selected typical wind power output day represent the worst situation in the region,the maximum and minimum values of wind wave momentum in the same period of different days are taken as the increase and decrease of wind power output in this period of typical wind power output day.Finally,the above model is verified by using the wind power output data of Hetian 200 MW wind farm.The results show that equipped with electrolyzer for wind farm can greatly reduce the abandoned wind,and the rated power of electrolyzer decreases with the increase of abandoned wind rate.

Low Voltage DC System Connected with Hydrogen Energy Storage and Its Business Model Construction

LI Xuejun, ZHANG Yijin, ZHAO Ermin, ZHANG Wenqing, GAO Fei, YUAN Tiejiang

2021, 0(7):  29-33.  doi:10.16628/j.cnki.2095-8188.2021.07.005

Asbtract ( 303 )   HTML ( 4)   PDF (1375KB) ( 191 )  

Figures and Tables | References | Related Articles | Metrics

In order to reduce the loss,improve the economy and power supply efficiency of the power grid,the flexible and efficient development and utilization of new energy are strengthened to improve the consumption of new energy.Hydrogen energy storage technology is connected to the low voltage DC system to improve the utilization rate of distributed generation and reduce the use of diesel generators to reduce pollution.Based on the non-cooperative game theory,the gamultiobj function in MATLAB is used to calculate the income of the government,the power generation side and the power grid side in different schemes,and the business model impact of government subsidies and investment allocation ratio on minimizing the green integrated energy system is discussed.Finally,the simulation results demonstrate the effectiveness of the analysis method and the business model based on non-cooperative game.

Electrical Design & Discussion

Optimization Design and Experimental Verification of Electromagnetic Repulsion Trip Mechanism of Medium Voltage DC Circuit Breaker

KONG Fanliang, XU Kai, MA Ziwen

2021, 0(7):  34-39.  doi:10.16628/j.cnki.2095-8188.2021.07.006

Asbtract ( 362 )   HTML ( 4)   PDF (1921KB) ( 231 )  

Figures and Tables | References | Related Articles | Metrics

In order to improve the current limiting level of the medium voltage DC circuit breaker and reduce the inherent operation time of the circuit breaker,an electromagnetic repulsion trip mechanism was designed to respond quickly to the fault short-circuit current.In this paper,the electromagnetic analysis software Ansoft Maxwell is used to simulate the dynamic characteristics of electromagnetic repulsion trip mechanism.By changing the radius and thickness of the repulsion disk and the air gap between repulsion disk and coil,the influence of various structural parameters on the performance of repulsion mechanism is obtained,which provides a basis for the design and optimization of electromagnetic repulsion trip mechanism.Finally,the motion characteristics of the mechanism are tested by experiments.The experimental results show that the dynamic characteristics of the electromagnetic repulsion trip mechanism are consistent with simulation results,and its performance index can meet the design requirements.This simulation method provides an effective way for the design and optimization of electromagnetic repulsion trip mechanism of medium voltage DC circuit breaker.

Optimization of Operation Mechanism of Low Voltage Molded Case Circuit Breaker Based on TRIZ Theory

ZHANG Haigen, CHENG Shaoyong, FU Zhichao

2021, 0(7):  40-44.  doi:10.16628/j.cnki.2095-8188.2021.07.007

Asbtract ( 387 )   HTML ( 4)   PDF (2748KB) ( 241 )  

Figures and Tables | References | Related Articles | Metrics

This paper used the TRIZ theory to optimize the operating mechanism of molded case circuit breaker.The short-circuit breaking problem of an elevated 400 A molded case circuit breaker was analyzed.Based on the simulation results of structural size and stress-strain analysis of the lower control arm,the characteristic parameters of the technical contradiction were obtained.According to the contradiction matrix,the invention principle and the improved theoretical solution were obtained.Finally,the improvement program was formed by studying the electrical design theory,performing the structural strength simulation,and analyzing the results of the short-circuit breaking test.The short-circuit breaking problem was solved by improving the breaking capacity of the product.

Designand Research on Improving Short-Circuit Breaking Capacity of DC MCCB

LI Xuelin, JIANG Guping, SHI Xiaorong

2021, 0(7):  45-50.  doi:10.16628/j.cnki.2095-8188.2021.07.008

Asbtract ( 751 )   HTML ( 46)   PDF (2122KB) ( 944 )  

Figures and Tables | References | Related Articles | Metrics

DC moulded case circuit breaker (MCCB) is an important part of low voltage electrical apparatus.The arc extinction is maily completed by the arc extinguishing system in MCCB.DC MCCB can use the method of increasing the number of poles and increasing capacity to improve the short-circuit breaking capacity.The method of increasing the number of poles increases the arc voltage by connecting more poles in series.The method of increasing capacity increases the arc voltage by increasing the arc extinguishing ability of a single arc extinguishing chamber.Inductance also plays a very important role in short circuit breaking.

Detection&Experiment

Discussion on Measurement of Harmonic Distortion Rate of Power Conversion System

YANG Yang, XU Xianqing, SHI Guifeng

2021, 0(7):  51-55.  doi:10.16628/j.cnki.2095-8188.2021.07.009

Asbtract ( 327 )   HTML ( 2)   PDF (2095KB) ( 319 )  

Figures and Tables | References | Related Articles | Metrics

There are many items of types test for power conversion system,and the relevant standards lack the necessary provisions for the methods and contents of some test items.As a result,different institution and person may cause large differences in the actual test of the project.This article mainly discusses some abnormal situations that occur in high-power power conversion system due to different loads and different wiring methods of test instruments during the test of total harmonic distortion rate,aiming to attract the attention of inspectors and provide reference for product improvement and standard improvement of power conversion system.

Research on Checking Method of Circuit-Breaker Breaking Capacity Based on Half Wave Energy of Last Current Loop

ZHANG Jian, ZHEN Chao, LU Bin, WEI Cunjin, NIU Liqun, JI Kun

2021, 0(7):  56-60.  doi:10.16628/j.cnki.2095-8188.2021.07.010

Asbtract ( 232 )   HTML ( 4)   PDF (1699KB) ( 301 )  

Figures and Tables | References | Related Articles | Metrics

The short-circuit current in the power gathering area,the core ring network and the load center is close to or even exceeds the interruption capacity of the circuit-breakers,and the DC time constant of the short-circuit current exceeds the rated time constant of the circuit-breakers,resulting in the actual short-circuit interruption capacity of the high-voltage AC circuit breaker is lower than the rated short-circuit interruption capacity.Firstly,the existing methods for checking the interruption capacity of circuit-breakers are discussed.Based on the analysis and study of domestic and foreign standards,a method for checking the interruption capacity based on the last current loop energy is proposed.The results show that the energy equivalence principle of last current loop can better characterize the energy in the process of arc interruption than the full-current equivalence principle.Finally,an assessment strategy of circuit-breaker interruption capacity based on the energy equivalence principle of last current loop is presented.The research content of this paper provides a new solution for checking the interruption capacity of circuit-breakers.

Design and Shielding Effectiveness Simulation of Anechoic Chamber with Multi-Magnetic Power Source

SONG Zihao, WU Guichu, ZHANG Shangcong, CHEN Chong

2021, 0(7):  61-65.  doi:10.16628/j.cnki.2095-8188.2021.07.011

Asbtract ( 185 )   HTML ( 2)   PDF (1542KB) ( 238 )  

Figures and Tables | References | Related Articles | Metrics

In order to study the influence of shielding effectiveness caused by introducing multi-magnetic circuit power source on anechoic chamber in a low-voltage apparatus in the EMC test.A simulation model for calculating the shielding effectiveness of an anechoic chamber is established and then the accuracy of the model is verified by experiments.Then the simulation model is used to calculate the influence of shielding effectiveness of anechoic chamber after a multi-magnetic circuit power source is introduced.A new shielding chamber around the anechoic chamber is proposed to store the multi-circuit magnetic system,and the control part of the multi-magnetic circuit system is separated from the shielding chamber.In this method a multi-magnetic circuit system is introduced into the chamber,but the high frequency electromagnetic noise is avoided.

Implementation Points and Test Capacity Calculation of 110 kV Transformer Sudden Short-Circuit Test with Short-Circuit Generator

XIANG Ruying, DUAN Liping, DING Zhengping

2021, 0(7):  66-70.  doi:10.16628/j.cnki.2095-8188.2021.07.012

Asbtract ( 322 )   HTML ( 3)   PDF (947KB) ( 183 )  

Figures and Tables | References | Related Articles | Metrics

Validation of transformer short circuit resistance is very important,so State Grid Corporation has taken active measures in recent years.In this paper,6 500 MVA and 3 200 MVA short-circuit generators are used as test power sources.According to GB 1094.5—2016,the implementation points of 110 kV power transformer sudden short-circuit test are analyzed and the test ability is calculated,including the selection of the output voltage of the intermediate test transformer.The configuration of two different lines is analyzed and compared.This paper puts forward the key points of implementation and the calculation of test capacity,which has guiding significance for the construction and transformation of such laboratories.

Experimental Research on Influence of Electromagnet Core Manufacturing Process Parameters on AC Contactor Performance

JIA Shitai, MI Liang, HU Wenjing

2021, 0(7):  71-74.  doi:10.16628/j.cnki.2095-8188.2021.07.013

Asbtract ( 282 )   HTML ( 2)   PDF (1008KB) ( 205 )  

Figures and Tables | References | Related Articles | Metrics

To study the influence of the core manufacturing process parameters of the "E" type oil-containing direct-acting electromagnet on the performance of the AC contactor is particularly important for professional contactor manufacturers.When manufacturing the electromagnet,change the three process parameters of the injection volume of the punching piece,the number of riveting pieces,and the amount of grinding to compare and verify that the process parameter changes have an impact on the product vibration (noise) and action that can reflect the characteristics and performance of the AC contactor.The three parameters of performance and coil temperature rise are statistically studied,and compared and analyzed with the standard prototype parameters,it is found that a smaller grinding amount can help improve product performance.

Proficiency Testing of Power Frequency Withstand Voltage Test of Low Voltage Apparatus and Analysis of Influencing Factors

AI Yun, ZHANG Yuxing

2021, 0(7):  75-77.  doi:10.16628/j.cnki.2095-8188.2021.07.014

Asbtract ( 311 )   HTML ( 8)   PDF (917KB) ( 244 )  

Figures and Tables | References | Related Articles | Metrics

In this paper,based on the proficiency testing of power frequency withstand voltage test of low voltage apparatus,the laboratories test the same sample according to the unified method,and the organizers evaluate the ability of the laboratories according to the pre-determined criteria.This proficiency testing can help laboratories to supervisory control their testing ability,compare the differences between laboratories,and promote the consistency of test results in power frequency withstand voltage test.

Application

Low-Cost Zero-Phase Open Circuit Protection Scheme Based on ZnO Varistor

LIANG Xiaohua, YANG Huanhong, XUE Bing, CHENG Xiangqun, FU Dongsheng, SUN Yan

2021, 0(7):  78-82.  doi:10.16628/j.cnki.2095-8188.2021.07.015

Asbtract ( 212 )   HTML ( 6)   PDF (1136KB) ( 160 )  

Figures and Tables | References | Related Articles | Metrics

The neutral point displacement of the three-phase four-wire system caused by the zero-phase open circuit,which leads to the over voltage damage of the equipment by power users,is still a pain point in the power supply sector.With the increase of the user’s harmonic load,there are more and more accidents that cause zero-phase open circuit overvoltage due to the zero line overburning,Only that terminal users install voltage protection circuit breakers can it solve this problem.However,the overvoltage protection circuit breakers are expensived to be widely applied.This paper proposes a zero-phase open circuit protection scheme using zinc oxide varistor combined with existing residual current protection devices for single phase user.In the case of zero-phase open circuit overvoltage,it can complete the reaction action quickly and reliably to protect the circuit,and has a low cost,which has very good practical value.

Realization of MQTT Protocol in Intelligent Power Gateway

ZHAO Ruilin

2021, 0(7):  83-87.  doi:10.16628/j.cnki.2095-8188.2021.07.016

Asbtract ( 315 )   HTML ( 13)   PDF (1665KB) ( 307 )  

Figures and Tables | References | Related Articles | Metrics

Intelligent power gateway is used for real-time collection,storage and analysis of data in substation or distribution station.The traditional intelligent power gateway does not support any Internet of things (IOT) communication protocol,so it is difficult to access the cloud platform.MQTT protocol is a widely used in the field of Internet of things communication.By studying the architecture and communication process of MQTT,a MQTT protocol library is compiled in the intelligent power gateway,which makes gateway have the ability to directly access cloud platform.Then a test has been done to verify the conformance and generality of MQTT library.