171 results on '"Harmonic voltages"'
Search Results
2. The strategy of second harmonic voltage match suppression for the DC-link in inverter
- Author
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Minghang Zhong, Jingjing Huang, and Xiangqian Tong
- Subjects
Physics ,Harmonic voltages ,business.industry ,Second harmonic voltage ,Electrical engineering ,Power coupling ,TK1-9971 ,General Energy ,Match suppression ,Inverter ,Bandpass filter ,Electrical engineering. Electronics. Nuclear engineering ,business ,Link (knot theory) - Abstract
In the two-stage converter such as PV renewable energy system, the second harmonic fluctuation exists in the DC voltage due to the power coupling between the DC-link and AC system. The second harmonic voltage in the DC link could increase the system loss and decrease the stability of the converter system, and its generation process and transmission mechanism are analyzed in this paper. The mathematical expression of second harmonic voltage in DC-link has been derived. A second band passing filter (BPF) feedback control loop is used to feedback the second harmonic ripple voltage in DC link into the statable modulation index. This strategy can decrease the second harmonic voltage in the DC-link and the third harmonic voltage in the AC sides. Finally, the control parameters are implemented using a simulation platform, and the match suppression strategy is validated by the simulation results.
- Published
- 2022
3. Research on the Standing Wave Phase Shifting Based Background Harmonic Voltages Attenuation
- Author
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Yuchao Yuan, Xin Li, Min Zhang, Baocheng Wang, Siming Zeng, Xiaofeng Sun, and Hong Shen
- Subjects
Standing wave ,Physics ,Optics ,Harmonic voltages ,business.industry ,Attenuation ,Electrical and Electronic Engineering ,business - Published
- 2022
4. Effects of Converter Harmonic Voltages on Transformer Insulation Ageing and an Online Monitoring Method for Interlayer Insulation
- Author
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Dayong Zheng, Pinjia Zhang, Qinghao Zhang, and Geye Lu
- Subjects
Materials science ,Harmonic voltages ,Ageing ,law ,Monitoring methods ,Sensitivity (control systems) ,Electrical and Electronic Engineering ,Transformer ,Transfer function ,Automotive engineering ,Voltage ,law.invention ,Power (physics) - Abstract
Power electronic converter can produce massive voltage stresses on the connected transformer, with great effects on electrical ageing of the insulation. Such effects can be diverse upon different insulation components under different harmonic voltages, which have not been well clarified. This paper aims at enhancing online monitoring of converter transformers from two aspects. First, electrical ageing evaluation models are developed for different types of transformer insulation. It is the first time to clarify the effects related to the component location and the ageing severity under differential-mode and common-mode (CM) voltages. Interlayer (IL) insulation faces a serious ageing threat and the line-lead component is aged with the severest degree. Second, CM voltages are used to build transfer function (TF) measurement for IL insulation monitoring. The key is to identify the optimal monitoring frequency with the highest sensitivity. Based on the analytical case introducing typical parameters, the TF performance is analyzed in different ageing conditions. Online experiments validate that the proposed method is effective and has good application prospect. The contributions lie in that the diverse ageing effects of converter harmonic voltages on different insulation components can be distinguished and online monitoring of IL insulation can be achieved effectively.
- Published
- 2022
5. IDENTIFICATION AND EVALUATION OF HARMONIC VOLTAGE SOURCES IN POWER SUPPLY SYSTEMS
- Author
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D. Kalyuzhniy
- Subjects
Identification (information) ,Harmonic voltages ,Computer science ,020209 energy ,020208 electrical & electronic engineering ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,02 engineering and technology ,Power (physics) - Abstract
Non-sinusoidal voltage in power supply systems leads to economic losses that need to be distributed and compensated. This problem is solved on the basis of the problem of identification and evaluation of the influence of voltage distortion sources. To date, existing methods for identifying and assessing the impact of harmonic voltage sources have significant limitations of practical implementation. This is due to their basic mathematical model and local approach to measuring the parameters of the network. In the given research the new mathematical model of identification and an estimation of harmonic voltage sources that is focused on the distributed measuring system is presented. The criterion for identifying harmonic voltage sources is the distorting nodal current. To adequately determine it, it is necessary not only to measure the parameters of the network mode in the base nodes by the currents of the higher harmonic components, but also to control the structure and parameters of the replacement circuit of the entire power supply system. To achieve this goal, it is proposed to use a distributed measuring system, which is based on vector measurement systems and control systems. The estimation of the influence of harmonic voltage sources is directly proportional to the distorting nodal current, where the coefficient of proportionality is either mutual or intrinsic resistance of power supply systems, that connects the location of the distortion source and the place for which its influence is estimated. In order to control the influence of measurement errors and determine the parameters of circuits for replacing elements of the power supply system, the method and algorithm for identifying and assessing the impact of harmonic voltage sources should be developed based on the principle of excluding one of the voltage distortion sources.
- Published
- 2021
6. Mitigation of Harmonic Voltage Amplification in Offshore Wind Power Plants by Wind Turbines With Embedded Active Filters
- Author
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Tonny Wederberg Rasmussen, Kim Høj Jensen, and Emerson Guest
- Subjects
Extra element theorem ,Wind power ,Harmonic voltages ,Grid voltage ,Renewable Energy, Sustainability and the Environment ,business.industry ,020209 energy ,020208 electrical & electronic engineering ,02 engineering and technology ,Harmonic analysis ,Offshore wind power ,Control theory ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,business ,Active filter - Abstract
In this paper, active filters are embedded in the grid-connected converter control of Type-IV wind turbines to reduce harmonic voltage amplification in offshore wind power plants (WPPs). The extra element theorem is employed to tune the active filters and determine the stability margin. Active filter tunings that satisfactorily reduce harmonic voltage amplification yet provide sufficient stability margin in the augmented system are identified. A running example is performed on a 270 MW offshore WPP comprised of 3-MW wind turbines implemented in real-time simulation as hardware-in-the-loop. Both converter and grid voltage harmonics are suppressed at WPP buses to below the stipulated planning levels.
- Published
- 2020
7. Fast Estimation of Harmonic Losses Caused by Inverter Carrier in Interior Permanent-Magnet Synchronous Motors by Using Combination of Time- and Frequency-Domain Finite-Element Analyses
- Author
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Yuma Terai, Kyoichi Iida, and Katsumi Yamazaki
- Subjects
Physics ,Harmonic voltages ,Permanent magnet synchronous motor ,Control theory ,Frequency domain ,Inverter ,Electrical and Electronic Engineering ,Synchronous motor ,Finite element method ,Electronic, Optical and Magnetic Materials - Abstract
This article describes a fast calculation method for harmonic losses caused by inverter carrier in interior permanent-magnet synchronous motors (IPMSMs) under a large number of driving conditions. In the proposed method, the harmonic loss caused by the largest component of the harmonic voltages is calculated by the linear frequency-domain finite-element analysis (FEA) with the differential permeability distribution obtained by the time-domain FEA. The total carrier loss is predicted by the variation in this largest harmonic component and sum of the square of harmonic voltages. The proposed method is applied to the efficiency-map calculation of an IPMSM. It is clarified that the total computational time is reduced to be 1/20th when compared with the conventional method.
- Published
- 2020
8. Dominant impedance method to assign harmonic voltage contributions at a point of common coupling
- Author
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Ivan Nunes Santos, Andréia Crico dos Santos, and José Carlos de Oliveira
- Subjects
Total harmonic distortion ,Harmonic voltages ,Computer science ,Modeling and Simulation ,Power system harmonics ,Energy Engineering and Power Technology ,Power quality ,Point of common coupling ,Electrical and Electronic Engineering ,Topology ,Electrical impedance - Published
- 2021
9. Sub-synchronous Harmonic Impedance Analysis of Doubly-fed Induction Generator Wind Turbine
- Author
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Xiang Wu, Yuanliang Lan, Hans-Gunter Eckel, Harald Weber, Tian Lan, Lijun Cai, and Hang Yin
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Physics ,0209 industrial biotechnology ,Harmonic voltages ,020208 electrical & electronic engineering ,Induction generator ,02 engineering and technology ,Turbine ,law.invention ,020901 industrial engineering & automation ,Control and Systems Engineering ,law ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Harmonic impedance ,Electrical impedance ,Doubly fed electric machine - Abstract
This paper researches the sub-synchronous harmonic impedance of doubly-fed induction generator (DFIG) wind turbine. For analyzing the harmonic impedances, additional harmonic voltage source is applied over the sub-synchronous frequency range and different operating conditions of the DFIG wind turbine are considered. Also, different mechanical parameter of the DFIG are changed for analyzing their influence on the harmonic impedances.
- Published
- 2019
10. Harmonic Voltage Induction on Pipelines: Measurement Results and Methods of Assessment
- Author
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Wilsun Xu, Bing Xia, Hyunjung Yong, Jing Yong, Thomas C. Hartman, and Nassif Alexandre
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Physics ,Harmonic voltages ,Field (physics) ,Power system harmonics ,020209 energy ,Energy Engineering and Power Technology ,02 engineering and technology ,Pipeline transport ,Harmonic analysis ,Electric power transmission ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Electronic engineering ,Electrical and Electronic Engineering ,Electrical impedance ,Voltage - Abstract
Inductive coordination between power lines and pipelines has been focused on the 60Hz/50Hz component in the past. Through field measurements and circuit-model based analysis, this research shows that harmonic currents in power lines can cause more significant voltage induction on pipelines. It is due to the relatively higher frequency and zero-sequence nature of some of the harmonic currents. In view of the findings, this paper presents two methods for assessing the severity of harmonic voltage induction. One is a circuit-model based method and the other is a field measurement based method.
- Published
- 2018
11. Review for 'Dominant impedance method to assign harmonic voltage contributions at a point of common coupling'
- Author
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bashir zad
- Subjects
Physics ,Harmonic voltages ,Point of common coupling ,Topology ,Electrical impedance - Published
- 2021
12. Author response for 'Dominant impedance method to assign harmonic voltage contributions at a point of common coupling'
- Author
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José Carlos de Oliveira, Ivan Nunes Santos, and Andréia Crico dos Santos
- Subjects
Physics ,Harmonic voltages ,Point of common coupling ,Topology ,Electrical impedance - Published
- 2021
13. Assignment of harmonic voltage contributions using the harmonic current injection method
- Author
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Ivan Nunes Santos and Andréia Crico dos Santos
- Subjects
Harmonic voltages ,business.industry ,Computer science ,Modeling and Simulation ,Power system harmonics ,Electrical engineering ,Harmonic ,Energy Engineering and Power Technology ,Power quality ,Electrical and Electronic Engineering ,Current (fluid) ,business - Published
- 2020
14. Author response for 'Assignment of harmonic voltage contributions using the harmonic current injection method'
- Author
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Andréia Crico dos Santos and Ivan Nunes Santos
- Subjects
Physics ,Harmonic voltages ,Quantum electrodynamics ,Harmonic ,Current (fluid) - Published
- 2020
15. Review for 'Assignment of harmonic voltage contributions using the harmonic current injection method'
- Author
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Qingxin Shi
- Subjects
Physics ,Harmonic voltages ,Quantum electrodynamics ,Harmonic ,Current (fluid) - Published
- 2020
16. Measurements of Harmonic Voltages at Multiple Locations in LV and MV Networks
- Author
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Tatiano Busatto, Naser Nakhodchi, and Math Bollen
- Subjects
Physics ,Harmonic order ,Total harmonic distortion ,Harmonic voltages ,020209 energy ,020208 electrical & electronic engineering ,02 engineering and technology ,Harmonic propagation ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,law.invention ,Computational physics ,Harmonic analysis ,law ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Transformer ,Low voltage - Abstract
This paper presents harmonic voltage measurements for a part of a distribution network including low-voltage (400 V) and medium-voltage (10 kV). Measurements were performed during 2017 and 2018 in the north of Sweden. This paper shows correlations between different harmonic orders in low voltage and the correlation between low and medium-voltage harmonics. This information can be used for harmonic propagation studies in distribution networks. The results showed significant correlation between the 5th and 7th harmonics for low-voltage side and very high correlation between 5th harmonic order in low-voltage and medium-voltage. It is also observed that 5th harmonic has almost the same values for all transformers connected to the same 40 kV network.
- Published
- 2020
17. Review for 'Dominant impedance method to assign harmonic voltage contributions at a point of common coupling'
- Author
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Qingxin Shi
- Subjects
Physics ,Harmonic voltages ,Point of common coupling ,Topology ,Electrical impedance - Published
- 2020
18. Measurement of the power in real time using LabVIEW based on IEEE standard 1459–2000
- Author
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Umamani Subudhi and Debani Prasad Mishra
- Subjects
Harmonic analysis ,Data acquisition ,Harmonic voltages ,Computer science ,business.industry ,Computation ,Harmonic ,Power quality ,business ,Signal ,Computer hardware ,Power (physics) - Abstract
This paper puts forward power measurement of harmonic signal by using an efficient algorithm. The obscure power segments and other power quality lists are estimated by definitions in the IEEE Standard 1459–2000. Spectrum of harmonic voltage and current signals are estimated independently, further the computations are made. Both PC reproductions and research center testing are finished looking at the proficiency (efficiency) of the proposed calculation. The real signals from Chroma programming are inputted through the Data Acquisition (DAQ) card and the results of the algorithm are viewed in LabVIEW. This algorithm is accurate and efficient, making it suitable for real-time applications.
- Published
- 2020
19. Research on Harmonic Current Functional Analysis of AC Arc Furnaces and Evaluation of Harmonic Level
- Author
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Aiping Pang, Jing Nong, Pu Deng, Zhuo Chen, Yongzhong Li, Shi Zeng, and Xiaojun Peng
- Subjects
Physics ,Arc (geometry) ,Function analysis ,Superposition principle ,Harmonic voltages ,Serial communication ,Harmonic ,Current (fluid) ,Topology ,Power (physics) - Abstract
This paper analyses the synchronous measuring data of harmonic current in AC arc furnaces with method of functional analysis, calculates the interaction angle between serial data of harmonic current in two arc furnaces, gets the conclusion that serial data of harmonic current in two arc furnaces are orthogonal, derives superposition formula for synthesizing harmonic currents of multi-arc furnaces and formula for evaluating harmonic voltage level beforehand in construction of power supply area of AC arc furnaces.
- Published
- 2019
20. Control Strategy to Mitigate Risk of Hybrid HVDC Continuous Commutation Failure
- Author
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Min Xin, Yao Wenfeng, Li Chengxiang, Lin Zizhao, Xia Cheng-jun, and He Xiaofeng
- Subjects
Harmonic voltages ,Computer science ,Control theory ,020209 energy ,Control (management) ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,02 engineering and technology ,Commutation ,AC power ,Fault (power engineering) ,Compensation (engineering) - Abstract
The mechanism of continuous commutation failure of HVDC is analyzed and harmonic is considered to be one of the reasons for the continuous commutation failure of HVDC during restoration after AC fault. The harmonic voltage compensation component is added to the link to improve the reactive power support of the MMC-HVDC to the AC system during recovery. Thereby mitigate the risk of occurrence of continuous commutation failure. The effectiveness of the proposed control strategy is verified on PSCAD/EMTDC.
- Published
- 2019
21. Evaluation of Commutation failure Risk for HVDC Caused by Harmonic Voltage
- Author
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Qi Wang, Xinyao Zhu, and Chen Jiahao
- Subjects
Harmonic voltages ,Computer science ,020209 energy ,020208 electrical & electronic engineering ,02 engineering and technology ,Superposition principle ,Control theory ,Harmonics ,High voltage direct current transmission ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Failure risk ,Commutation ,Transient (oscillation) - Abstract
The commutation failure is one of the most common faults in high voltage direct current transmission (HVDC) systems. The research on the HVDC commutation failure has made some achievements at home and abroad. However, the influence of harmonic on the commutation failure of HVDC has not been studied thoroughly. Based on the commutation process of HVDC and the commutation voltage-time area analysis, a harmonic influence factor is derived, and the influence of harmonics on the commutation process in HVDC is quantitatively analyzed. The evaluation index of the risk of commutation failure due to harmonics, which is defined as the harmonic influence superposition E sup , is proposed, and a method using E sup to evaluate the risk of commutation failure caused by harmonic voltage is given consequently. Finally, based on the PSCAD/EMTDC electromagnetic transient simulation platform, the proposed evaluation indicators are simulated and verified.
- Published
- 2019
22. Evaluation of Harmonic Voltage Emission Level Considering Harmonic Impedance of Photovoltaic Side
- Author
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Ziteng Liu, Yonghai Xu, and Xu Zhang
- Subjects
Imagination ,Chemical substance ,Materials science ,Harmonic voltages ,Acoustics ,media_common.quotation_subject ,Computer Science::Neural and Evolutionary Computation ,Photovoltaic system ,Physics::Optics ,Grid ,Harmonic analysis ,Physics::Popular Physics ,Computer Science::Systems and Control ,Science, technology and society ,Harmonic impedance ,media_common - Abstract
Considering that when the photovoltaic inverters are connected to the grid through filters, the harmonic impedance at the photovoltaic side of the common connection points may not satisfy the condition that the harmonic impedance at the photovoltaic side is much larger than that at the background side(which is satisfied in the traditional grid), so that when estimating the harmonic voltage emission level, the influence of the harmonic impedance on the photovoltaic side can not be neglected. A method for evaluating the harmonic voltage emission level considering the harmonic impedance on the photovoltaic side is proposed. Firstly, the harmonic impedance of photovoltaic side is estimated according to the parameters of photovoltaic inverters, filters and lines. Then, the harmonic voltage emission level is evaluated based on the estimated harmonic impedance of photovoltaic side. Finally, the advanced and accuracy of the proposed method is verified by simulation and comparison with other methods.
- Published
- 2019
23. A Novel Leakage Current Index for the Field Monitoring of Overhead Insulators Under Harmonic Voltage
- Author
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Sivaji Chakravorti, Biswendu Chatterjee, and R. Ghosh
- Subjects
010302 applied physics ,Engineering ,Harmonic voltages ,business.industry ,020208 electrical & electronic engineering ,Electrical engineering ,Condition monitoring ,Insulator (electricity) ,Hardware_PERFORMANCEANDRELIABILITY ,02 engineering and technology ,01 natural sciences ,Field monitoring ,Harmonic analysis ,Measurement device ,Control and Systems Engineering ,Harmonics ,0103 physical sciences ,Hardware_INTEGRATEDCIRCUITS ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Electrical and Electronic Engineering ,business ,Voltage - Abstract
Leakage current measurement is the most reliable and effective method for condition monitoring of overhead insulators deployed in the field. However, a major challenge in the leakage current based insulator monitoring is to interpret the indices extracted from the leakage current measurements under varying harmonic content in system voltage. This paper reports the possibility of employing the instantaneous value of time-integral of leakage current as a low-sensitive parameter for the monitoring of leakage current in overhead insulators in the presence of voltage harmonics. It has been shown that any change in the harmonic content of the system voltage has a significant influence on the harmonic characteristics of the leakage current, but has a comparatively less severe effect on the time-integral. The monitoring technique has been validated through laboratory recorded experimental data and incorporated in an online measurement device that has been tested in the laboratory.
- Published
- 2018
24. Tracing harmonic contributions of multiple distributed generations in distribution systems with uncertainty
- Author
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Shouxiang Wang, Kai Wang, Lei Wu, Xiang Liu, and Ying Zhang
- Subjects
Trace (linear algebra) ,Harmonic voltages ,020209 energy ,020208 electrical & electronic engineering ,Energy Engineering and Power Technology ,02 engineering and technology ,Tracing ,law.invention ,Distribution system ,Control theory ,law ,Harmonics ,Intermittency ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Electrical and Electronic Engineering ,Affine arithmetic ,Mathematics - Abstract
With an increasing number of inverter-interfaced distributed generations (DG) being integrated into distribution systems, significant harmonics could be injected to bring an adverse impact on distribution system operation. These harmonics usually fluctuate due to the variability and intermittency of DG outputs. However, different DGs, depending on their locations and sizes, may present different harmonic contributions in distribution systems, and it is important to identify which DG has the largest influence on a specific bus. In this paper, a Complex Affine arithmetic based Three-phase Harmonic Power Flow method (CATHPF) is proposed to trace the harmonic contributions of individual DGs to distribution systems. The contribution of each DG to harmonic voltage (CDGHV) is calculated based on CATHPF. The CATHPF method is tested on an IEEE 33-bus distribution system. The proposed CATHPF method can quantitatively evaluate harmonic contributions of individual DGs in distribution systems, and in turn guide the effective allocation of harmonic control equipment.
- Published
- 2018
25. Overcurrent Protection from Earth Faults Based on Higher Harmonics for Compensated 6- to 10-kV Cable Networks
- Author
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V. A. Martynov, E. S. Shagurina, T. Yu. Shadrikova, and V.A. Shuin
- Subjects
Harmonic voltages ,Computer science ,020209 energy ,02 engineering and technology ,Limiting ,Overcurrent ,Power (physics) ,Absolute measurement ,Control theory ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Sensitivity (control systems) ,Electrical and Electronic Engineering ,Current (fluid) - Abstract
Devices based on the method of absolute measurement of the level of higher harmonics in zerosequence currents of connections of a protected object are the most commonly used for protection from earth faults in compensated 6- to 10-kV cable networks of industrial and urban power-supply systems. However, many years of operating experience have shown that the technical refinement (the selectivity and the sensitivity) of overcurrent protection from earth faults based on the method of absolute measurement of higher harmonics is not always sufficient. One of the reasons for the low technical refinement of these protection devices is the inaccuracy in estimating the maximum and minimum possible higher harmonics levels in the earth-fault current of compensated 6- to 10-kV cable networks, which are required for the selection of the operating current settings and the sensitivity determination. The main factors influencing the maximum and minimum higher harmonics levels in the earth-fault current and their ratio were revealed on the basis of the computational experiments using the imitation models for 6- to 10-kV cable networks, the limiting values of these levels were determined, an determination of the harmonics-level instability in the fault current for cable networks with different total load compositions was given, and its interrelation with the fluctuations of the total coefficient of harmonic voltage components on 6- to 10-kV buses of network power centers was established. The conditions of applicability and the area of application of overcurrent protection from this type of failure based on the use of higher harmonics of the zero-sequence current for different objects of 6- to 10-kV compensated cable networks were determined taking into account the above estimates. Specifications for a method for selecting the operating current settings were proposed.
- Published
- 2018
26. Variations in harmonic voltage at the sub-10-minute time scale
- Author
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Math Bollen, Sarah K. Ronnberg, and Aurora Gil-de-Castro
- Subjects
Harmonic voltages ,Scale (ratio) ,Computer science ,020209 energy ,020208 electrical & electronic engineering ,Energy Engineering and Power Technology ,Time resolution ,02 engineering and technology ,Set (abstract data type) ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Electronic engineering ,Relevance (information retrieval) ,Electrical and Electronic Engineering ,Raw data ,Data transmission - Abstract
This paper presents the statistical analysis of variations in harmonic voltage in the time scale between 1 second and 10 min, a time scale that is rarely considered in studies but that is of relevance for incorrect operation of end-user equipment. The paper also introduces a set of novel power-quality indices quantifying these variations and it gives recommendations on how to include these indices in the power-quality-monitoring framework provided by IEC 61000–4–30. The statistics and the illustration of the novel indices are based on measurements of harmonic 2 through 40 with 1-second time resolution at 154 locations in 16 countries. The proposed power-quality indices are a compromise between storing large amounts of raw data with high time resolution, resulting in the different big-data challenges, and completely neglecting this time scale. Two important findings from this paper are that this time scale should not be completely neglected and that information on this time scale can be recorded without excessive increase in the need for data transmission and storage.
- Published
- 2021
27. Implementation and performance evaluation of a harmonic filter for use in adaptive single‐phase reclosing
- Author
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Ozenir Dias and Maria Cristina Tavares
- Subjects
Harmonic filtering ,Harmonic voltages ,Computer science ,020209 energy ,Energy Engineering and Power Technology ,02 engineering and technology ,Transmission system ,Field (computer science) ,law.invention ,Harmonic analysis ,Adaptive filter ,Control and Systems Engineering ,Filter (video) ,Relay ,law ,Control theory ,Real Time Digital Simulator ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Electronic engineering ,Single phase ,Electrical and Electronic Engineering ,Digital filter ,Voltage - Abstract
This paper presents an adaptive single-phase auto-reclosing method based on harmonic voltage measurement through a digital harmonic filter. This filter and the transmission system were modelled in a real-time digital simulator (RTDS). A distance relay was used for protection and reclosing, responding as if it was in field operation. The studied system was based on an actual 500 kV Brazilian system. This work highlights the advantage of using the adaptive technique when compared with regular fixed dead-time procedure.
- Published
- 2017
28. A DC-side Harmonic Equivalent Circuit Based on Switching Function
- Author
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Junpeng Ma, Lijuan Fan, Tianqi Liu, He Huang, Yuqing Dong, and Shunliang Wang
- Subjects
Harmonic analysis ,Leakage inductance ,Harmonic voltages ,Computer science ,business.industry ,law ,High voltage direct current transmission ,Electrical engineering ,Inverter ,Equivalent circuit ,business ,Transformer ,law.invention - Abstract
High voltage direct current transmission (HVDC) has been widely used in China in recent years due to its advantages of large transmission capacity, long distance, and low cost. It is significant to establish models for harmonic analysis in HVDC system. The switching function is used to get DC side harmonic voltage source, and the leakage inductance of transformer in both rectifier and inverter stations is equivalent to the DC side. A DC side harmonic equivalent calculation circuit for 6/12-pulse HVDC system is proposed accordingly. Using the simulation examples built in PSCAD/EMTDC, the correctness of the proposed model is verified.
- Published
- 2019
29. A Practical Case of Harmonic Voltage Mitigation at a Baking Facility in Norway
- Author
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D. Matvoz and M. Maksic
- Subjects
Harmonic voltages ,law ,Computer science ,Harmonics ,Harmonic ,Power quality ,Transformer ,Automotive engineering ,law.invention - Abstract
─ An industrial baking oven was installed at a baking facility in Norway. After some time, a neighboring network user connected to the same low-voltage transformer complained to the distribution company about the problem of the occasional but persistent LED lights flickering. Problem occurrence coincided with the installation of a new baking oven at the bakery. There was a serious threat to the bakery that it would be disconnected from the distribution network if solution to this problem was not found. Problems of elevated noise at the low-voltage supply point due to harmonics and some gas-tube lighting equipment failure at the bakery were also clear indicators of power quality problems. Therefore, troubleshooting power quality measurements of all disturbance-significant loads at the bakery were made. Using the measurement results, the source of harmonic current has been identified. After that most appropriate solution for mitigation of harmonic current was identified. After the application of mitigation, power quality problems in the low-voltage network were not present any more. Even more, power quality in this low-voltage industrial network is now compliant even with the strict Norwegian power quality legislation.
- Published
- 2019
30. Capacitor switching methodology for responsibility sharing of harmonic voltage distortions
- Author
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Andréia Crico dos Santos, José Carlos de Oliveira, and Ivan Nunes Santos
- Subjects
Total harmonic distortion ,Harmonic voltages ,business.industry ,Computer science ,Power system harmonics ,Electrical engineering ,Energy Engineering and Power Technology ,law.invention ,Capacitor ,law ,Modeling and Simulation ,Power quality ,Electrical and Electronic Engineering ,business - Published
- 2019
31. A Novel Offset Function for Three-Level T-Type Inverter to Reduce Switching Loss
- Author
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My-Ha Le, Vinh-Thanh Tran, Thanh-Hai Quach, Duc-Tri Do, Ngoc-Anh Truong, and Minh-Khai Nguyen
- Subjects
Physics ,Offset (computer science) ,Harmonic voltages ,Control theory ,Multilevel inverter ,020208 electrical & electronic engineering ,0202 electrical engineering, electronic engineering, information engineering ,Inverter ,02 engineering and technology ,Three level ,Pulse-width modulation ,Voltage - Abstract
In this paper, a new pulse width modulation (PWM) scheme for three-level T-type inverter is proposed to reduce switching loss of the inverter. The proposed modulation technique is based on the offset function being 3rd harmonic voltage. The control voltage of phase, which has largest absolute value of load current, moves into the top or bottom of the carriers to have no switching in this phase. Therefore, the switching loss of the inverter is reduced. The switching loss of the inverter with the proposed PWM method is 33% lower compared to the conventional sinusoidal PWM method. The theoretical analysis is verified by simulation and experimental results.
- Published
- 2019
32. Fast Estimating Method of Effective Life of Power Cable in Industrial Environment
- Author
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Anik Goswami, Shivprakash Bihari, Pradip Kumar Sadhu, and Utpal Goswami
- Subjects
Harmonic voltages ,Computer science ,law ,Harmonics ,Service life ,Harmonic ,Power quality ,Power cable ,Transformer ,Automotive engineering ,Electric arc furnace ,law.invention - Abstract
With the wide and ever-increasing application of non-linear loads, such as variable speed drives, personal computers, compact fluorescent lamps (CFL), arc furnace transformers and high frequency electrical heaters, power quality of the supply is severely disturbed. Low power quality means introduction of higher order harmonic frequency, harmonic current and harmonic voltage in supply system. These harmonics result in unbalance in a three-phase system and this causes a considerable amount of I2R loss in the cable and increases the cable resistance. Increment of r. m.s current and cable resistance results in the increment of joule losses of the cable. This paper describes a method of determining cable temperature rise with respect to harmonic current present in the system and this helps to estimate the remaining service life of the power cable. The proposed method helps to determine the effective life of cable and thus reduce insulation failure rate. The proposed method also helps to increase reliability of supply system for critical process industry.
- Published
- 2019
33. A Tuning Method of Selective Harmonic Voltage Compensator for Distributed Generators
- Author
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Yifeng He, Kai Li, Caimeng Wei, Wanjun Lei, Qibo Tang, Xiaojie Zhang, Tian Li, and Guo Lin
- Subjects
Harmonic voltages ,Computer science ,Control theory ,020209 energy ,Harmonics ,020208 electrical & electronic engineering ,Synchronous frame ,Distributed generator ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,02 engineering and technology ,Single phase ,Voltage - Abstract
In islanded micro-grid, the distributed generators are required to regulate the local grid voltage and frequency, especially when non-linear loads produce current harmonics inducing same frequencies voltage harmonics. In order to suppress the voltage harmonics, a selective harmonic compensator is always needed. For single phase distributed generator, a method based on single equivalent synchronous frame which is used to extract harmonics is modified as selective harmonic controller. Considering the lack of parameter tuning method for controller, based on the detailed analysis of the controller, a design procedure of controller parameters is proposed. Simulation and preliminary experiment prove the design approach.
- Published
- 2019
34. Investigation of high order harmonic for signal extraction in Matteucci effect based fluxgate magnetic sensors
- Author
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Tomasz Charubin, Roman Szewczyk, and Michał Nowicki
- Subjects
Materials science ,Harmonic voltages ,Acoustics ,Signal extraction ,Computer Science::Networking and Internet Architecture ,Harmonic ,ComputerSystemsOrganization_SPECIAL-PURPOSEANDAPPLICATION-BASEDSYSTEMS ,High order ,Signal ,Sensitivity (electronics) ,Fluxgate compass ,Magnetic field - Abstract
Fluxgate sensors are known for being cheap, robust and sensitive magnetic field sensors. Presented sensor uses Matteucci effect (ME) in its principle of magnetic field sensing, while using harmonic voltage signal extraction typical for fluxgate sensors. In order to increase the sensitivity of used sensor, investigation of high order harmonic of signal was researched.Fluxgate sensors are known for being cheap, robust and sensitive magnetic field sensors. Presented sensor uses Matteucci effect (ME) in its principle of magnetic field sensing, while using harmonic voltage signal extraction typical for fluxgate sensors. In order to increase the sensitivity of used sensor, investigation of high order harmonic of signal was researched.
- Published
- 2019
35. Impact of a distributed photovoltaic generation on power quality in a low voltage distribution network at Universidad de El Salvador
- Author
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Jose Ramos, Juan Erazo, and Karen Agreda
- Subjects
Harmonic analysis ,Distribution networks ,Harmonic voltages ,business.industry ,Flicker ,Photovoltaic system ,Electrical engineering ,Environmental science ,Power quality ,Voltage distortion ,business ,Low voltage - Abstract
This paper presents an assessment of voltage distortion, flicker and slow voltage variation caused by a distributed rooftop photovoltaic system in the low voltage distribution network at the campus of Universidad de El Salvador. Individual triplen harmonic voltage levels and longterm flicker index levels assessed in field measurements at the campus exceeded the compatibility levels established in most international power quality standards. The assessments also show a growing trend in all triplen harmonic voltage levels, short term flicker severity index and long-term flicker severity index levels, after the photovoltaic generation started operation.
- Published
- 2018
36. Influence of Harmonics on Each Converter Station in Multi-HVDC System
- Author
-
Xu Xuan, Lin Yang, Weiyong Jiang, Kai Ma, Yanan Li, and Chunlin Guo
- Subjects
Physics ,Harmonic voltages ,business.industry ,020209 energy ,Electrical engineering ,02 engineering and technology ,Transmission (telecommunications) ,Harmonics ,Transfer (computing) ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Current (fluid) ,Reduction (mathematics) ,business ,Voltage - Abstract
The converter stations of different HVDC systems located in the adjacent networks, which have short electrical distance, forming a Multi-HVDC system. In the Multi-HVDC system, exists the harmonics interaction. This paper establishes the Multi-HVDC harmonic impedance model. The harmonic self-impedance, harmonic transfer impedance and harmonic transfer coefficient are defined to measure the influence of each harmonic current on the harmonic voltage of converter stations; giving the concept of harmonic voltage transfer amplification and transmission reduction. Taking Yin Chuandong Station and Lingzhou Station as examples, which belong to the Ning-Dong and Ning-Zhe Multi-HVDC systems. Calculate the harmonic self-impedance, harmonic transfer impedance and harmonic transfer coefficient of two converter stations. The results indicate that 3rd, 5th, 7th harmonics have greater impacts on the converter station. When the 5th harmonic current is injucted into the Ling Zhou Station, the harmonic voltage induced on Yin Chuandong Station is higher than that of in Lingzhou Station. After transmitted through the AC system, the effect of harmonic current on the remote converter station is increased, the voltage transfer amplification has occurred. All the results are verified by PSCAD simulation.
- Published
- 2018
37. Modeling and Analysis of Harmonic Currents of GSC Caused by Harmonic Grid Voltage and Dead Time
- Author
-
Oi Zhou, Heng Nian, and Chao Wu
- Subjects
010302 applied physics ,Coupling ,Physics ,Harmonic voltages ,Grid voltage ,020208 electrical & electronic engineering ,02 engineering and technology ,Dead time ,Grid ,Topology ,01 natural sciences ,Harmonic analysis ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Electrical impedance - Abstract
This paper deduces a mathematic model of grid side converter(GSC) to quantitatively analyze the harmonic currents caused by two factors, i.e., grid background harmonic voltages and dead time effect. The impedance of GSC respectively corresponding to these two factors is built and the harmonic currents can be precisely calculated. The model also explains the coupling phenomenon of two kinds of harmonic currents and the generation mechanism of the phenomenon. Finally, the comparison of simulation results and calculation results validates the effectiveness of the model.
- Published
- 2018
38. Influences of temperature on partial discharge behavior in oil-paper bounded gas cavity under pulsating DC voltage
- Author
-
Lianwei Bao, Jian Li, Lin Du, Dali Huang, and Youyuan Wang
- Subjects
Materials science ,Harmonic voltages ,Astrophysics::High Energy Astrophysical Phenomena ,020209 energy ,02 engineering and technology ,01 natural sciences ,law.invention ,Dc voltage ,Electrical resistivity and conductivity ,law ,0103 physical sciences ,Thermal ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Transformer ,010302 applied physics ,business.industry ,Direct current ,Time constant ,Electrical engineering ,High voltage ,Mechanics ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Electromagnetic coil ,Bounded function ,Partial discharge ,Physics::Accelerator Physics ,business ,Voltage - Abstract
The oil-paper insulation of valve-side windings in a high voltage direct current (HVDC) converter transformer is subjected to both complicated voltage and severe thermal stresses. Partial discharge (PD) occurring in oil-paper bounded cavities is influenced by voltage stress type as well as temperature. This paper presents PD behaviors in an oil-paper bounded gas cavity under pulsating DC voltages. The voltage across the gas cavity and PD inception voltages at different test conditions are analyzed. Influences of temperature on statistical PD distributions and parameters are also presented. A numerical model is used to interpret PD behaviors under pulsating DC voltages and various temperatures. Experimental results and theoretical statements show that the temperature exhibits a great influence on the behaviors of cavity discharge under pulsating DC voltages. Volume resistivity, gas pressure, charge decay time constant, and electron generation rate are the primary parameters influencing PD behaviors at different temperatures.
- Published
- 2016
39. Excilamp with a coaxial feedline
- Author
-
V. V. Savin, V. O. Nekhoroshev, and D. V. Schitz
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,Harmonic voltages ,Physics::Instrumentation and Detectors ,business.industry ,020208 electrical & electronic engineering ,Transistor ,02 engineering and technology ,law.invention ,Physics::Plasma Physics ,law ,Electrode ,0202 electrical engineering, electronic engineering, information engineering ,Optoelectronics ,Inverter ,Coaxial ,business ,Transformer ,Excitation ,Voltage - Abstract
We describe a mathematical model of electrophysical processes occurring in the system consisting of a transistor inverter, an oscillatory circuit, a step-up transformer, a long feedline, and a barrier-discharge lamp. We propose and test a method for effective transmission of a high-frequency voltage from a power supply to the barrier-discharge lamp via a long coaxial line in which the voltage was applied to the electrodes of the lamp in the form of harmonic voltage bursts at a frequency close to the self-resonant frequency of the excitation system.
- Published
- 2016
40. An improved time-delay addition method for MOSA resistive leakage current extraction under applied harmonic voltage
- Author
-
Mohammad Mirzaie and Masume Khodsuz
- Subjects
Engineering ,Resistive touchscreen ,Harmonic voltages ,Surge arrester ,business.industry ,020209 energy ,Applied Mathematics ,02 engineering and technology ,Condensed Matter Physics ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Electrical and Electronic Engineering ,business ,Instrumentation ,Voltage ,Leakage (electronics) ,Metal oxide surge arrester - Abstract
The most monitoring techniques of metal oxide surge arresters are based on harmonics analysis of resistive leakage current. Therefore, the extraction of resistive component from total leakage current is required. Up to now, several methods have been proposed for resistive leakage current extraction such as time-delay addition method. This method is only able to separate accurate resistive component under pure sinusoidal applied voltage. An improved time-delay addition method is proposed in this paper which is able to extract surge arrester resistive component under applied harmonic voltage. To accomplish this purpose, experimental tests have been performed on 20 kV surge arrester and obtained voltage and leakage current signals have been applied to the proposed and previous algorithms for resistive component extraction. In addition to investigate the ability of proposed algorithm, a typical surge arrester has been simulated in ATP-EMTP software and total leakage currents have been applied to both algorithms for resistive leakage current extraction. Results show that the proposed method is able to extract resistive component under applied harmonic voltage more accurate than previous one. Therefore, it is an improvement with respect to previous one that only works for sinusoidal voltage.
- Published
- 2016
41. Evaluation of Contribution by Each Different Group of Load to the Fifth Harmonic Voltage in the Electric Power System
- Author
-
Masato Watanabe, Naotaka Okada, and Kenji Yukihira
- Subjects
Physics ,Harmonic voltages ,Group (mathematics) ,business.industry ,020209 energy ,Phase angle ,Electrical engineering ,Energy Engineering and Power Technology ,02 engineering and technology ,Electric power system ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,business - Published
- 2016
42. A basic study on novel islanding detection method for photovoltaic inverters by positive feedback of harmonic voltage
- Author
-
Yoshiaki Yoshida and Hirokazu Suzuki
- Subjects
Engineering ,Harmonic voltages ,business.industry ,020209 energy ,estimation of synchronous phase angle ,020208 electrical & electronic engineering ,Photovoltaic system ,positive feedback ,02 engineering and technology ,Signal ,harmonic voltage detection ,Control theory ,Distributed generator ,0202 electrical engineering, electronic engineering, information engineering ,Islanding ,Electronic engineering ,Harmonic ,islanding detection ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,business ,lcsh:TK1-9971 ,Network analysis ,Positive feedback - Abstract
We have proposed an islanding detection method using the harmonic current as an active signal. In particular, in order to inject the active signal efficiently, we have proposed a method to synchronize the harmonic voltage caused by the active signal of DG with the harmonic voltage caused by the harmonic current of the load. To verify the validity of the proposed methods, we performed the simulation by PSCAD/EMTDC and the calculation by circuit theory. We clarified that the synchronous injection can be greatly reduced the islanding detection time.
- Published
- 2016
43. Analysis of power flow in wind farm with matpower
- Author
-
Z. D. Wu, P. Dong, and Yuan-Rui Chen
- Subjects
Wind power ,Harmonic voltages ,Distribution networks ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,020209 energy ,02 engineering and technology ,AC power ,Automotive engineering ,Power flow ,Physics::Space Physics ,0202 electrical engineering, electronic engineering, information engineering ,Harmonic ,Astrophysics::Solar and Stellar Astrophysics ,Environmental science ,business ,MATLAB ,computer ,Physics::Atmospheric and Oceanic Physics ,computer.programming_language ,Voltage - Abstract
It can be predicted that the proportion of wind power in the power grid will gradually increase with the maturity of the application technology in wind power. Based on the development of wind power, this paper is to research the impact of wind farm on power grid. Matpower is used to calculate the buses voltage, reactive power and power loss of the IEEE-33 network with two wind farms. And matlab is used to analyze the harmonic voltage influence to the network. The results show that the active power of the wind farm has a significant effect on the distribution network. The quantity of harmonic current injected into the system is also maximal during rate wind power output, which must be tested and controlled strictly.
- Published
- 2017
44. A Nine-Switch Unified Power Quality Conditioner with Enhanced Repetitive Controller
- Author
-
Hong-Hee Lee and Dang-Minh Phan
- Subjects
Harmonic voltages ,Computer science ,Control theory ,Modulation ,Voltage sag ,Harmonic ,Power quality ,Voltage ,Power (physics) - Abstract
The 9-switch power converter can provide two sets of output terminals like the conventional back-to-back power converter. In this paper, the unified power quality conditioner (UPQC) is developed by using the 9-switch power converter with the enhanced repetitive controller (RC). The proposed 9-switch UPQC can mitigate concurrently harmonic current and voltage problems together with voltage sag/swell issues. And also, the switching loss is reduced significantly by using the discontinuous modulation strategy for the 9-switch UPQC. The characteristics of the proposed 9-switch UPQC are evaluated by simulation, and its superior performance is verified.
- Published
- 2017
45. Probabilistic comparison of methods for calculating harmonic current emission limits
- Author
-
Max Domagk, Farhad Safargholi, Max Hoven, Jan Meyer, Karsten Kuech, and Kaveh Malekian
- Subjects
Engineering ,Harmonic voltages ,business.industry ,020209 energy ,Probabilistic logic ,Electrical engineering ,Electromagnetic compatibility ,High voltage ,02 engineering and technology ,Harmonic analysis ,Compatibility (mechanics) ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,business ,Low voltage ,Voltage - Abstract
The limitation of harmonic currents emitted by individual equipment and customer installations is essential in order to maintain harmonic voltages below compatibility or planning levels and consequently to ensure Electromagnetic Compatibility (EMC). At present, a large variety of methods exists worldwide for calculating harmonic emission limits, majorly expressed as harmonic currents. A systematic search on available methods has been performed for more than 70 countries from all over the world. Finally 16 individual methods for low voltage (LV), medium voltage (MV) and high voltage (HV) networks have been selected for a detailed quantitative comparison based on a probabilistic approach. This paper compares harmonic emission limits of the different methods for individual customer installation and is focused on generating installations. The first part provides details about the framework of comparison; the second part summarizes the results for the different voltage levels.
- Published
- 2017
46. The simulation research on electric arc furnace combined model based on MATLAB
- Author
-
Zhi Hu, Taiping Guo, Hongmei Zhu, and Xiaobo Liu
- Subjects
Harmonic analysis ,Harmonic voltages ,Scope (project management) ,Computer science ,Energy balance ,Mechanical engineering ,MATLAB ,computer ,Source model ,Simulation ,computer.programming_language ,Electric arc furnace - Abstract
This paper first briefly introduces several kinds of typical model of electric arc furnace model and its scope of application, including the harmonic voltage source model, energy balance model and the time-varying resistance model, then build the simulation model and analysis its operating characteristics for each model in MTALAB/Simulink simulation. finally, this paper puts forward a kind of electric arc furnace combination model based on different models, combines the advantages of each model and the feasibility of the model is verified by practical example simulation.
- Published
- 2017
47. Analysis of Sequences Harmonics Measurement Impact Using Potential Transformers Grounded through Ferroresonance Eliminator
- Author
-
Yi Huang Chen, Yu Chao Li, Jie Wu, and Kai Pei Liu
- Subjects
Engineering ,Ferroresonance in electricity networks ,Harmonic voltages ,business.industry ,Ground ,Potential transformer ,General Medicine ,Experimental research ,law.invention ,law ,Harmonics ,Electronic engineering ,Transformer ,business ,Excitation - Abstract
This paper has carried on the theoretical analysis and experimental research on the different impacts of positive, negative and zero sequence harmonic voltage measurement using three single-phase potential transformers with neutral point grounded through a ferroresonance eliminator. First, the influences of the different excitation characteristics among the three PTs and the non-linear excitation characteristics of a single-phase PT on different sequences harmonic voltage measurement are analyzed theoretically. Then the physical experiment platform has been designed, and the experiments of three-phase PTs on different sequences harmonic voltage measurement are carried on. The experiment results verified that the influences of three-phase PTs on different sequences harmonic measurement are not the same at this grounding mode.
- Published
- 2014
48. An Islanding Detection Method for Photovoltaic Power Generation System Using Fluctuation Characteristic of PCC Harmonic Voltage
- Author
-
Luo Yun
- Subjects
Engineering ,Harmonic voltages ,business.industry ,Photovoltaic system ,General Engineering ,Wavelet ,Transformation (function) ,Photovoltaic power generation ,Control theory ,Electronic engineering ,Harmonic ,Islanding ,business ,Voltage - Abstract
In the photovoltaic power generation system, the harmonic voltage of the point of common coupling (PCC) is determined by system disturbance, local load and photovoltaic power generation system itself together. Based on the fluctuations of this harmonic voltage, a new islanding detection method for the PV system is proposed. By extracting the higher harmonic components from the wavelet transformation of point of common coupling (PCC) voltage, and then taking its fluctuations as the islanding identification and detection index, non-detection zone (NDZ) can be eliminated, without a plus disturbance. According to IEEE Std.1547, simulated verification of the proposed method is accomplished in the ideal photovoltaic grid system. When the PCC voltage and frequency are within the normal range, it can not only give a fast and accurate detection to the occurrence of islanding, but also identify the false islanding, such as voltage dips and switching loads, effectively avoiding false detection caused by the false islanding.
- Published
- 2014
49. Partial Linear Method for Background Harmonic Voltage Estimation
- Author
-
Hai Qing An, Xiu Fang Jia, and Shao Guang Zhang
- Subjects
Bandwidth management ,symbols.namesake ,Square error ,Harmonic voltages ,Basis (linear algebra) ,Control theory ,Linear regression ,General Engineering ,Taylor series ,symbols ,Constant (mathematics) ,Linear methods ,Mathematics - Abstract
The linear regression method which will be influenced by fluctuations could only calculate constant background harmonic voltage. To make up the limitation, this paper studies partial linear method. The method expands fluctuant background harmonic voltage at a time in accordance with Taylor series. On the basis of least sum of square error, the objective function selected by the method considers the influence of weight and uses bandwidth control each size of weight. This method can calculate fluctuant background harmonic voltage accurately. A case study based on the IEEE 14-bus test system is conducted and the results indicate that fluctuant background harmonic voltage can be obtained effectively and accurately by the proposed method.
- Published
- 2014
50. Considering Load Characteristics Harmonic Penetration in Zhengzhou Converter Station Nearly
- Author
-
Shuang Yin Dai, Xiao Peng Yu, Jun Zhong Yang, Bo Zhang, and Zhi Qiang Dai
- Subjects
Engineering ,Harmonic voltages ,business.industry ,General Engineering ,Electrical engineering ,Penetration (firestop) ,computer.software_genre ,Simulation software ,Hybrid system ,Electronic engineering ,Power grid ,Harmonic voltage distortion ,business ,computer - Abstract
This paper presents the rules of harmonic penetration in Zhengzhou harmonic voltage level. National standards limit the harmonic voltage distortion level in the buses, so study the UHV AC/DC hybrid system is significant to power grid. In order to find out the harmonic voltage level near Zhengzhou converter station, a method has been proposed in this paper, including the models of radiation power grid, load characteristics and converter station's AC filter. Finally, according to Zhengzhou converter station power frame sets up a detail model in the simulation software packages PSCAD/EMTDC to study the law of harmonic penetration.
- Published
- 2014
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