搜搜做题作业网英语翻译电子电力方面的英文论文,字数无太多要求最好在2000字之内.感激不尽狂鞠躬!
来源：学生作业帮 编辑：搜搜做题作业网作业帮 分类：英语作业 时间：2024/07/10 04:25:12
英语翻译
电子电力方面的英文论文,字数无太多要求
最好在2000字之内.
感激不尽
狂鞠躬!
电子电力方面的英文论文,字数无太多要求
最好在2000字之内.
感激不尽
狂鞠躬!
Abstract:With the development of power electronics technology,harmonic hazards has become increasingly serious,harmonic governance issues has been imminent.On the power source for electronic devices harmonic analysis and concluded that its harm and the corresponding harmonic management principles and comprehensive management,and management of a harmonic outlook.
Key words:power electronics; harmonics; hazards; inhibition
INTRODUCTION
With the development of power electronics technology,power electronic devices to the extensive application of power system harmonics caused serious pollution.Various power electronic equipment in the transport,metallurgical,chemical and other industrial traffic the extensive application of harmonics in the grid problem is becoming increasingly serious,many low power factor of power electronic devices to the power grid additional burden on the quality of power and influence,Therefore,the power electronic devices harmonic pollution has become hinder the development of power electronics technology major obstacles.Therefore,inhibition harmonic pollution and improve the power factor of power electronics technology has become a major issue in the.This paper focus on the key issues of power through electronic harmonic sources and the danger of understanding and analysis,and control of pollution from the relationship between the consideration of a comprehensive management approach on the final harmonic trends in the development of comprehensive management of the prospect.
A power electronic device - the main source of harmonics
Nonlinear load is a harmonic sources,which caused grid voltage distortion,in the voltage several times with the whole of the fundamental frequency component.Harmonic as the main source of power for various electronic devices mainly AC-DC converter (rectifiers,inverters,chopper,Drives),as well as bidirectional thyristor controlled switching equipment,as well as internal power system Variable Flow equipment,such as HVDC rectifier valve and the valve,and other inverter.Below its harmonics generated an analysis of the situation.
1.1 Rectifier
As a DC power supply devices,rectifiers widely used in various occasions.Figure 1 (a) and Figure 1 (b) respectively for the single-phase and three-phase circuits typical.In rectifier devices,AC power supply for the current rectangular wave,rectangular wave of the fundamental frequency for the current and Jibeiai several times for the high-frequency harmonic current waveform synthesis.Obtained by Fourier series of rectangular wave of high harmonics In fundamental component I1 and the largest ratio of 1 / n,with the trigger control angle 伪,and the decrease of overlap angle 渭 for the increase of harmonic wave components have reduced trend.
In addition,the existing research results indicate that:Rectifier harmonic current operation mode of the size,has a direct impact,therefore consider adjusting the voltage and current rectifier,it is best to conduct overlap angle,as well as for harmonic phase pressure drop calculations,in order to determine safe and economical operation mode when the control close to 40 掳 angle 伪,overlapping in the 8 掳 angle 渭 about the circumstances are often the most serious state of harmonic,so to go through,as far as possible through the correct choice of regulating transformers tap in order to avoid Harmonic most serious point [1].
1.2 exchange regulator
Exchange regulator used for lighting dimming and induction motor speed,and so on.Figure 2 (a) and 2 (b) respectively for the single-phase and three-phase circuits typical.Exchange regulator and the harmonic frequency rectifier basically the same.
Frequency Converter 1.3
Frequency converter is AC / AC Converter behalf of equipment,when used as motor speed control devices,which contain a change with the output frequency band edge,as for the frequency change,the more complicated harmonic content.
Universal Converter 1.4
GM converter input circuits are all from the diode bridge rectifier and DC capacitor components in Figure 3 (a) shows,this circuit impedance input current waveform with the different big difference.In the source impedance relatively small cases,the waveform for the lanky Zhaier high-waveform in Figure 3 (b) solid line shows the contrary,when the source impedance relatively large,its waveform for the dwarf and wide flat waveform Figure 3 (b) shown in dotted line.
In addition to these typical converter will be a great number of harmonics,household appliances is not to be ignored harmonic sources.Such as television sets,battery chargers.Although their individual capacity little,but because a lot of volume,they injected into the power supply system to the harmonic components can not be ignored.
2 harmonic hazards
Harmonic hazards of the public network include:
1) make a public network components have additional harmonic loss and reduce the power generation,power transmission equipment efficiency,a large number of 3rd harmonic flow neutral line,the line will cause overheating or even a fire;
2) impact of the normal work of electrical equipment,in addition to additional wear and tear caused,and also enable a motor mechanical vibration,noise and over-voltage,transformer partial serious overheating,capacitors,cables and other equipment overheating,insulation aging,shortened life expectancy,resulting damage;
3) common cause in the local power grid and parallel resonant series resonance,so that harmonic magnification so that the aforementioned hazards greatly increase,or even lead to serious accidents;
4) will lead to protection and automatic device misoperation,and electrical measuring instrument measurement inaccurate;
5) to neighbouring interfere with communications systems,light,noise and lower the quality of communication,information led to heavy loss of the communications systems do not work properly.
3 harmonic management principles
To improve power quality,we must strengthen the management of the harmonics.In restricted to the utility grid harmonic source harmonic current injection,will be allowed to limit the harmonic voltage within the scope of the principle.First it is necessary to have systems in the harmonic sources and distribution,in the harmonic limit its scope in order to allow access,not curing the management measures must be taken to prevent the spread of harmonics.For this reason the International Electrotechnical Commission (IEC) and the United States have recommended IEEE standards such as IEEE provisions of the current standard harmonic limits shown in Table 1.China Power Grid with the actual level and the standard of other developed countries voltage distortion sine-rate provisions in table 2.
Table 1 harmonic current limits (IEEE519-1992 Provisions)
Isc / IL
H
Key words:power electronics; harmonics; hazards; inhibition
INTRODUCTION
With the development of power electronics technology,power electronic devices to the extensive application of power system harmonics caused serious pollution.Various power electronic equipment in the transport,metallurgical,chemical and other industrial traffic the extensive application of harmonics in the grid problem is becoming increasingly serious,many low power factor of power electronic devices to the power grid additional burden on the quality of power and influence,Therefore,the power electronic devices harmonic pollution has become hinder the development of power electronics technology major obstacles.Therefore,inhibition harmonic pollution and improve the power factor of power electronics technology has become a major issue in the.This paper focus on the key issues of power through electronic harmonic sources and the danger of understanding and analysis,and control of pollution from the relationship between the consideration of a comprehensive management approach on the final harmonic trends in the development of comprehensive management of the prospect.
A power electronic device - the main source of harmonics
Nonlinear load is a harmonic sources,which caused grid voltage distortion,in the voltage several times with the whole of the fundamental frequency component.Harmonic as the main source of power for various electronic devices mainly AC-DC converter (rectifiers,inverters,chopper,Drives),as well as bidirectional thyristor controlled switching equipment,as well as internal power system Variable Flow equipment,such as HVDC rectifier valve and the valve,and other inverter.Below its harmonics generated an analysis of the situation.
1.1 Rectifier
As a DC power supply devices,rectifiers widely used in various occasions.Figure 1 (a) and Figure 1 (b) respectively for the single-phase and three-phase circuits typical.In rectifier devices,AC power supply for the current rectangular wave,rectangular wave of the fundamental frequency for the current and Jibeiai several times for the high-frequency harmonic current waveform synthesis.Obtained by Fourier series of rectangular wave of high harmonics In fundamental component I1 and the largest ratio of 1 / n,with the trigger control angle 伪,and the decrease of overlap angle 渭 for the increase of harmonic wave components have reduced trend.
In addition,the existing research results indicate that:Rectifier harmonic current operation mode of the size,has a direct impact,therefore consider adjusting the voltage and current rectifier,it is best to conduct overlap angle,as well as for harmonic phase pressure drop calculations,in order to determine safe and economical operation mode when the control close to 40 掳 angle 伪,overlapping in the 8 掳 angle 渭 about the circumstances are often the most serious state of harmonic,so to go through,as far as possible through the correct choice of regulating transformers tap in order to avoid Harmonic most serious point [1].
1.2 exchange regulator
Exchange regulator used for lighting dimming and induction motor speed,and so on.Figure 2 (a) and 2 (b) respectively for the single-phase and three-phase circuits typical.Exchange regulator and the harmonic frequency rectifier basically the same.
Frequency Converter 1.3
Frequency converter is AC / AC Converter behalf of equipment,when used as motor speed control devices,which contain a change with the output frequency band edge,as for the frequency change,the more complicated harmonic content.
Universal Converter 1.4
GM converter input circuits are all from the diode bridge rectifier and DC capacitor components in Figure 3 (a) shows,this circuit impedance input current waveform with the different big difference.In the source impedance relatively small cases,the waveform for the lanky Zhaier high-waveform in Figure 3 (b) solid line shows the contrary,when the source impedance relatively large,its waveform for the dwarf and wide flat waveform Figure 3 (b) shown in dotted line.
In addition to these typical converter will be a great number of harmonics,household appliances is not to be ignored harmonic sources.Such as television sets,battery chargers.Although their individual capacity little,but because a lot of volume,they injected into the power supply system to the harmonic components can not be ignored.
2 harmonic hazards
Harmonic hazards of the public network include:
1) make a public network components have additional harmonic loss and reduce the power generation,power transmission equipment efficiency,a large number of 3rd harmonic flow neutral line,the line will cause overheating or even a fire;
2) impact of the normal work of electrical equipment,in addition to additional wear and tear caused,and also enable a motor mechanical vibration,noise and over-voltage,transformer partial serious overheating,capacitors,cables and other equipment overheating,insulation aging,shortened life expectancy,resulting damage;
3) common cause in the local power grid and parallel resonant series resonance,so that harmonic magnification so that the aforementioned hazards greatly increase,or even lead to serious accidents;
4) will lead to protection and automatic device misoperation,and electrical measuring instrument measurement inaccurate;
5) to neighbouring interfere with communications systems,light,noise and lower the quality of communication,information led to heavy loss of the communications systems do not work properly.
3 harmonic management principles
To improve power quality,we must strengthen the management of the harmonics.In restricted to the utility grid harmonic source harmonic current injection,will be allowed to limit the harmonic voltage within the scope of the principle.First it is necessary to have systems in the harmonic sources and distribution,in the harmonic limit its scope in order to allow access,not curing the management measures must be taken to prevent the spread of harmonics.For this reason the International Electrotechnical Commission (IEC) and the United States have recommended IEEE standards such as IEEE provisions of the current standard harmonic limits shown in Table 1.China Power Grid with the actual level and the standard of other developed countries voltage distortion sine-rate provisions in table 2.
Table 1 harmonic current limits (IEEE519-1992 Provisions)
Isc / IL
H
英语翻译电子电力方面的英文论文,字数无太多要求最好在2000字之内.感激不尽狂鞠躬!
英语翻译我需要一个英文版的中国历史故事,字数不要太多,在100~300字之内.Thank you~
古希腊语科学精神最好涉及亚里士多德、怀疑什么的,要写论文,个人感觉意义不大,所以希望东这方面的达人帮帮忙,感激不尽 字数
介绍澳大利亚的导游词,在地形,气候,地理位置,世界上的活化石博物馆这几个方面介绍,字数不用太多.求各位高人,感激不尽.
世界史人物的论文初二水平,简单一点,字数最好别太多300字~800字最好
求3D打印选修论文论文要求：写一篇关于3D打印某一个方面的论文,字数不少于3000字,参考文献不少于10篇,其中英文不少
求一篇金融英语文献最好是金融危机方面的,全英文的,字数在1万字以上的
英语翻译论文摘要还要翻译英文,就是下面这段话,感激不尽~该项目包括电子文件服务中心和数据服务中心两大部分,在同一个系统架
英语翻译1 文章字数要求是多少?2 每篇文章 字数不少于800字3 您这片文章字数 太多了 / 太少了.4 你的文章字数
英语翻译论文的题目,要求翻译成英文,百度谷歌的翻译都不行,要求语法方面通顺的,
求论文,春秋无义战选修课的结业论文,最好从正面讲解春秋无义战,单讲春秋就行,比如通过讲解几个典型的战例,字数要求1000
入团志愿书字数不要太多,最好在200字以下.