针对多端柔性直流电网(multi-terminal direct current grid based on modular multilevel converter,MMC-MTDC)故障诊断存在的人工整定阈值过程复杂、高阻故障不易检测的问题,提出一种基于行波特征的诊断方法。首先,通过分析系统的故...针对多端柔性直流电网(multi-terminal direct current grid based on modular multilevel converter,MMC-MTDC)故障诊断存在的人工整定阈值过程复杂、高阻故障不易检测的问题,提出一种基于行波特征的诊断方法。首先,通过分析系统的故障特征,得出边界元件对高频信号的阻滞作用;其次,利用经验模态分解(empirical mode decomposition,EMD)对功率进行分解,得到本征模态函数(intrinsic mode function,IMF)分量,将其能量值作为故障特征量训练由卷积神经网络(convolutional neural network,CNN)和双向门控循环单元(bidirectional gated recurrent unit,BiGRU)组成的CNN-BiGRU网络;然后,采用开普勒优化算法(Kepler optimization algorithm,KOA)和注意力机制(attention mechanism,AM)对CNN-BiGRU网络进行改进,实现MMC-MTDC的故障诊断;最后,在PSCAD/EMTDC中搭建仿真模型。结果表明,该方法不仅可以实现母线故障和线路故障的检测,还可以在满足保护可靠性和速动性的前提下,解决高阻故障保护易拒动的问题。展开更多
In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numero...In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numerous practical uses for the capability to extract key characteristics from secondary property data and utilize these characteristics to forecast home prices.Using regression methods in machine learning to segment the data set,examine the major factors affecting it,and forecast home prices is the most popular method for examining pricing information.It is challenging to generate precise forecasts since many of the regression models currently being utilized in research are unable to efficiently collect data on the distinctive elements that correlate y with a high degree of house price movement.In today’s forecasting studies,ensemble learning is a very prevalent and well-liked study methodology.The regression integration computation of large housing datasets can use a lot of computer resources as well as computation time,and ensemble learning uses more resources and calls for more machine support in integrating diverse models.The Average Model suggested in this paper uses the concept of fusion to produce integrated analysis findings from several models,combining the best benefits of separate models.The Average Model has a strong applicability in the field of regression prediction and significantly increases computational efficiency.The technique is also easier to replicate and very effective in regression investigations.Before using regression processing techniques,this work creates an average of different regression models using the AM(Average Model)algorithm in a novel way.By evaluating essential models with 90%accuracy,this technique significantly increases the accuracy of house price predictions.The experimental results show that the AM algorithm proposed in this paper has lower prediction error than other comparison algorithms,and the prediction accuracy is greatly improved compared with other algorithms,and has a good experimental effect in house price prediction.展开更多
基金This work was supported in part by Sichuan Science and Technology Program(Grant No.2022YFG0174)in part by the Sichuan Gas Turbine Research Institute stability support project of China Aero Engine Group Co.,Ltd(Grant No.GJCZ-0034-19)。
文摘In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numerous practical uses for the capability to extract key characteristics from secondary property data and utilize these characteristics to forecast home prices.Using regression methods in machine learning to segment the data set,examine the major factors affecting it,and forecast home prices is the most popular method for examining pricing information.It is challenging to generate precise forecasts since many of the regression models currently being utilized in research are unable to efficiently collect data on the distinctive elements that correlate y with a high degree of house price movement.In today’s forecasting studies,ensemble learning is a very prevalent and well-liked study methodology.The regression integration computation of large housing datasets can use a lot of computer resources as well as computation time,and ensemble learning uses more resources and calls for more machine support in integrating diverse models.The Average Model suggested in this paper uses the concept of fusion to produce integrated analysis findings from several models,combining the best benefits of separate models.The Average Model has a strong applicability in the field of regression prediction and significantly increases computational efficiency.The technique is also easier to replicate and very effective in regression investigations.Before using regression processing techniques,this work creates an average of different regression models using the AM(Average Model)algorithm in a novel way.By evaluating essential models with 90%accuracy,this technique significantly increases the accuracy of house price predictions.The experimental results show that the AM algorithm proposed in this paper has lower prediction error than other comparison algorithms,and the prediction accuracy is greatly improved compared with other algorithms,and has a good experimental effect in house price prediction.