The reasonable power quality assessment model of microgrid is significant to the planning and management for a microgrid. In the power quality assessment, how to extract and integrate the implicative information in different evaluation indicators, to realize the comprehensive power quality assessment, are needs to be further studied. To solve the above problems, a microgrid power quality assessment model based on multivariate Gaussian distribution and local sensitivity analysis is proposed in this paper. Firstly, the probability density function is used to integrate the individual assessment indicators, and the correlation between the assessment indicators is reflected by the covariance matrix, and then the above characteristics of evaluation indicators are quantized to be as the indicator weights by using the local sensitivity. Comparing with the traditional power quality assessment method, the proposed evaluation model is more suitable for microgrid. Finally, an example is developed to verify that the overall situation of microgrid power quality can be reasonably reflected by the proposed evaluation model.

Aiming at the current limit value of six steady-state energy indexes, the current radar method is used for reference. A method of comprehensive evaluation of power quality based on improved radar method is proposed, which improves the power quality index Type radar pattern to represent the steady-state indicator. Each of the main indicators corresponds to a partial ring, and the angle of the annular portion is mainly affected by the size of the weight. Compared with the previous radar map method to maintain the independence of the indicators and a single indicator of the binding data assessment. The method has the advantages of good feasibility.

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Herein we describle a facile synthesis of sulphonic acid oxime esters in acetonitrile from the corresponding sulphonic acids and oximes catalyzed by the environmental friendly 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU) in the presence of triethylamine (TEA) under mild conditions. The present approach offers the advantages of a clean reaction, simple methodology, employing readily available catalyst, short reaction duration, high selectivity and high yield.