Two Parts Harmonic Pricing Scheme Considering Harmonic Responsibility

With the wide access of non-linear load and distributed power in power system,the harmonic pollution caused by these problems become more and more serious,but the huge economic losses caused by these problems can’t be reflected in the traditional energy price.The rationality of the existing tariff collection scheme can no longer be satisfied under the harmonic conditions.For this reason,in order to improve the objectivity,scientific and rationality of power metering and power quality evaluation,it is necessary to formulate a reasonable harmonic electricity price system.While charging for harmonic pollution,it is necessary to divide the responsibility of the harmonics on the user side and the system side so that the nonlinear users(users of harmonic sources)can be charged the harmonic electricity fees they should bear,and the users who have adopted new technologies to reduce harmonic pollution will be rewarded,or the linear users(users of non-harmonic sources)who have been polluted by harmonic pollution will be compensated to achieve reasonable charging and performance.Effectively motivate non-linear users to actively control harmonics and keep the power system in a healthy state.This thesis first builds an equivalent model for non-linear users.In the current mainstream non-linear user modeling methods,Norton equivalent model is easy to operate and more suitable for harmonic responsibility calculation,so this thesis selected it as a non-linear user model construction method.Then,the calculation methods of the parameters needed to build Norton equivalent model are introduced,and the methods are reorganized and classified.The comparison results show that the reference impedance method is simpler and easier to operate.After analysis,it is considered that the basic wave resistance method subordinate to it is more suitable for the comprehensive calculation method of harmonic responsibility designed in this thesis.A specific example is set up to verify the rationality of the harmonic source equivalent model built by the fundamental resistance method,with the voltage and current at the common connection points unchanged before and after modeling.Secondly,based on expert experience and user needs,as well as the fluctuation of system harmonics(background harmonics),this thesis puts forward reasonable conditions for evaluating the harmonic responsibility evaluation method: first,the evaluation results can meet the different requirements of system side and user side for harmonic index respectively;second,the evaluation results can reflect the fluctuation of system harmonics sensitively.At the same time,the harmonic index and frequency are not uniform when calculating harmonic responsibility.Based on the power theory of IEEE Std.1459-2010,the harmonic responsibility index set is established,and several common subjective and objective weighting methods are used to calculate the weighting of each index.In order to unify the objective and subjective information,a combinatorial calculation model for finding conditional extremes by constructing Lagrange functions is established based on the optimization theory.Finally,the Norton equivalent model is used to simulate and verify the results.Through comparative analysis,the results show that the comprehensive evaluation method of harmonic responsibility using combination weighting method can satisfy two rationality conditions of the evaluation method of harmonic responsibility at the same time.Therefore,it is believed that this method can make the evaluation results more accurate and reasonable,and closer to the actual situation.Next,considering that the cost of harmonics includes the economic loss of harnessing harmonics and other economic losses caused by harnessing harmonics,it is necessary to evaluate the economic loss of harnessing harmonics.This thesis deduces the economic loss function of harmonic control based on the quality engineering theory from the angle of product,combines the average price and lifetime of active filters on the market,and refers to the national standard "Power quality: public network harmonics"(GB/T 14549-93)For the restriction data of harmonic standards,a method for evaluating economic losses of harmonic control is proposed,and its feasibility is verified by a simulation example.Subsequently,through theoretical analysis of the traditional price setting scheme and the process of energy measurement under the harmonic conditions,it is believed that the harmonics are not checked and unfair charges exist.Therefore,this thesis draws on the idea of two-part electricity price system in the active power price formulation scheme,and puts forward twopart harmonic electricity price formulation scheme considering the harmonic responsibility,which corresponds to the harmonic capacity price and the harmonic power price respectively,and combines the harmonic responsibility.On the one hand,this is conducive to improving China’s electricity tariff adjustment scheme and achieving fair charges under harmonic conditions.On the other hand,it has a positive role in encouraging non-linear users to actively invest in harmonic pollution control and maintaining the healthy state of the electrical environment of power system.Finally,in order to reflect the integrity of the design method in this thesis,a detailed flowchart is given,and a multi-harmonic source simulation model is built as a comprehensive example to better fit the actual situation.The harmonic source equivalent model,the corresponding harmonic responsibility of each user,the economic loss assessment of harmonic control and the collection of harmonic electricity fees are completed in turn.It is proved that the proposed method has good coherence and logic.