Amicrogrid Based On The Fusion Of Multiple Indicators And Logarithmic Correction Power Quality Assessment And Application Study

With the development of renewable energy technologies,microgrid is received more and more attention and research.The study of power quality assessment and application of microgrids can be used to provide important support for the stable and economic operation of microgrids,as well as a scientific reference for microgrid management.Therefore,further research is needed on how the various evaluation indicators of microgrid power quality can be reasonably integrated and how the microgrid power quality evaluation methods can be optimised and applied to the power quality management of microgrid.Today,power quality assessment and its applications are being researched to achieve certain results as well as to solve the microgrid power quality problem to a certain extent.However,there are certain shortcomings in the integration of assessment indicators,the optimisation of assessment models and the application of assessment results,and further research is needed.For example,firstly,further research is needed on how to assess the power quality of microgrids based on traditional methods,where implicit information between indicators is explored,and where multiple assessment indicators are fused into a whole.Secondly,the rational distribution of subjective and objective weights,as well as the consideration that the combined weights will be influenced by individual weights that deviate to a greater extent,need to be further studied.Thirdly,once the results of the microgrid power quality assessment have been determined,further research is needed on how to use the results of the microgrid power quality assessment to target the management of microgrid power quality.In conclusion,the above issues will be examined step by step in this paper.Firstly,to address the traditional objective weighting method,which only analyses the influence of a single assessment index on power quality to determine the weight,but does not consider the joint influence of multiple indicators to assess the power quality of microgrid,a microgrid power quality assessment model based on multivariate gaussian distribution combined with local sensitivity analysis is proposed in this paper.The probability density function of the multivariate gaussian distribution is used to unify the assessment indicators in a functional form to construct the assessment model.The problem of analysing only individual assessment indicators for power quality assessment in traditional assessment objective methods and the failure to take full account of the interaction between indicators,resulting in assessment results that do not conform to the actual power quality problems in the microgrid has been resolved.Local sensitivity analysis is used to enable the integration of multivariate gaussian distribution assessment models with indicator weights,and the problem that the weight values obtained by traditional objective assessment methods do not include the intrinsic links between indicators is solved.Once the indicator weights have been determined,probabilistic statistical quantification methods are used in combination with the assessed indicator weights,so that the final quantitative assessment results are obtained.The microgrid power quality can be reasonably assessed by this method.Secondly,since the experience of legal experts and the needs of users are not taken into account by objective assignment.Therefore,subjective assignment methods are introduced on the basis of objective assignment methods and the two are fused to form a comprehensive assignment method.Therefore,based on the above-mentioned objective weighting method,the Analytic Hierarchy Process(AHP)weighting method is introduced in this paper,and a logarithmic correction based comprehensive assessment method for microgrid power quality is proposed.Improved AHP subjective weighting method and multivariate Gaussian distribution with local sensitivity objective weighting method were used to determine the subjective and objective weights of each assessment indicator and to obtain the combined weights using the minimum information discrimination method.The problem of irrational allocation of subjective and objective weights in traditional integrated assessment methods is solved;the logarithmic correction method is used to correct the obtained integrated weights.Traditional integrated assessment methods when the result of a single weight deviates to a large extent,resulting in the integrated weights being shifted towards the weight with the larger deviation,thus resulting in the assessment results not matching the actual situation is solved.Further,the comprehensive assessment method of microgrid power quality proposed in this paper is applied to the research of microgrid power quality management strategies.Based on the microgrid power quality assessment method in this paper,a microgrid power quality governance strategy based on multiple intelligences consistency and hashing algorithm is proposed.For microgrid power quality problems,multiple power electronic converters within the microgrid are collaboratively controlled to achieve the management of microgrid power quality.Finally,verification by example shows that microgrid power quality can be reasonably quantified by the evaluation method proposed in this paper.The microgrid power quality problem can be managed by the microgrid power management strategy proposed in this paper.After the management measures were taken,the microgrid power quality assessment score increased from 3.382 to 7.7,and the power quality was effectively improved.