Font Size: a A A

Harmonic Responsibility Determination For The Distributed Network Under Distributed Generation Access

Posted on:2020-07-03Degree:MasterType:Thesis
Country:ChinaCandidate:J LuoFull Text:PDF
GTID:2392330599976030Subject:Electrical engineering
Abstract/Summary:PDF Full Text Request
With the increasing penetration of new energy power generation systems represented by photovoltaics and wind power in distribution networks,the power electronic devices have been applied massively that leading to harmonic pollution and power quality deterioration.A set of “reward and punishment schemes” has been proposed whose implementation relies on the accurate harmonic responsibility determination.However,the distributed power supply has injected new characteristics into the harmonics of the distribution network,which brings new problems to the harmonic responsibility determination.It is necessary to carry out the research on the harmonic responsibility determination of the distribution network with distributed generation access.Focusing on the harmonic responsibility determination under the access of distributed generation,the topic has carried out research work on three aspects: random fluctuation of background harmonic,photovoltaic access distribution network and wind power access distribution network,including the following content:1)The randomness of background harmonic fluctuation leads to the difficulty of harmonic responsibility determination,a new method combining Joint Approximate Diagonalization of Eigen-matrices with a set of data filter criterion is proposed considering the symbolic characteristic of the harmonic impedance and the fact that the utility harmonic impedance is far less than the customer harmonic impedance.Firstly,Joint Approximate Diagonalization of Eigen-matrices is used to decompose the harmonic voltage and the harmonic current to obtain the mixed matrix.Secondly,the order uncertainty and amplitude uncertainty are corrected by the symbol discriminant method and the proportional coefficient method respectively;Then,the data filter criterion is used to obtain the harmonic impedance.Finally,the harmonic responsibility is calculated according to the definition equation.The simulation analysis and measured data analysis are carried on with IEEE 13-bus system and the simulative results show that the proposed method has high accuracy and adaptation compared with conventional fluctuation method and dominant fluctuation method.2)The access of photovoltaic in the power distribution network leads the change of the power distribution network in harmonic characteristics especially in harmonic impedance characteristics,which brings new challenges to determine the harmonic responsibility.In order to determine the harmonic responsibility accurately,firstly,the sinusoidal function is adopted to fit the output power characteristics of photovoltaic and harmonic impedance characteristics,the power flow calculation is adopted to analyze the influence of photovoltaic access on the harmonic characteristic in this paper;Then,the change of the harmonic impedance characteristic of the power distribution network including photovoltaic is analyzed,and the varying coefficient regression is introduced to estimate the harmonic impedance;Finally,the specific harmonic responsibility is calculated according to harmonic responsibility formula.To verify the accuracy and adaptability of the proposed method,the simulation analysis is carried on with IEEE 13-bus system and the simulative results show that the proposed method has higher accuracy and adaptability compared with the fluctuation method and the robust regression method.3)The access of wind power in the distribution network leads to the injection of the new harmonic characteristic,which brings new challenges to the harmonic responsibility determination.In order to determine the harmonic responsibility,the measured data is adopted directly to analyze the influence of wind power on the harmonic characteristics of the power distribution network;The quantile regression is introduced to adopted to estimate the harmonic impedance according to the harmonic characteristics of the wind power.Based on the above,the harmonic responsibility of each harmonic source is calculated by the harmonic responsibility index factor.In order to verify the accuracy and adaptability of the proposed method,the verification analysis is performed on the IEEE 13-bus system.The results show that the proposed method has better accuracy and adaptability than fluctuation method and robust regression method.
Keywords/Search Tags:harmonic responsibility determination, harmonic impedance estimation, background harmonic, photovoltaic, wind power
PDF Full Text Request
Related items