基于深度学习的永磁同步电机温度预测模型

Temperature prediction model for permanent magnetsynchronous motors based on deep learning

为有效预测永磁同步电机的温度,首先使用嵌套结构对门控循环单元(gated recurrent unit,GRU)进行改进,提出一种嵌套式门控循环单元(nested gated recurrent unit,NGRU)网络,NGRU能对相关温度特征中的噪声进行过滤,并挖掘温度随时间变化的规律,再经过非线性变换提取深层的温度特征;然后提出一种新型深度学习模型,即一维卷积神经网络(1D convolutional neural networks,1D-CNN)串联NGRU(1D-CNN tandem NGRU,CNGRU),CNGRU利用1D-CNN对输入特征进行初步提取,得到多角度的永磁同步电机相关温度特征作为NGRU的输入,以串联的结构融合二者的优势,得到永磁同步电机的预测温度。试验结果表明,对比其他循环网络在定子轭、定子齿和定子绕组温度上的预测表现,NGRU均方误差平均降低12.44%,无穷范数平均降低0.3619;CNGRU在此基础上比NGRU均方误差平均降低13.29%,无穷范数平均降低0.5796。CNGRU比NGRU及其他循环网络对永磁同步电机温度的预测,具有更高的精度和稳定性,这为保证电机的安全稳定运行提供了技术保障。

To efficiently predict the temperature of permanent magnet synchronous motors,firstly,the gated recurrent unit(GRU)was improved by using a nested structure to propose the nested gated recurrent unit(NGRU)network,being capable of filtering the noise in the relevant temperature features and exploring the pattern of temperature variation over time,and then extracting the deeper temperature features through a non-linear transformation;secondly,a novel deep learning model(1D-CNN tandem NGRU,CNGRU)was proposed,namely one-dimensional convolutional neural networks(1D-CNN)in tandem with NGRU.The CNGRU harnessed 1D-CNN for the initial extraction of input features to obtain multi-angle temperature features related to permanent magnet synchronous motors,serving as input to the NGRU to obtain the predicted temperature of permanent magnet synchronous motors by fusing the advantages of both in a tandem structure.The experimental results show that,compared with the prediction performance of other recurrent networks on the stator yoke,the stator teeth and the stator winding temperature,the NGRU mean square error is reduced by 12.44%on average and the infinite horizon by 0.3619 on average;on this basis CNGRU reduces the mean square error by an average of 13.29%and the infinite horizon by an average of 0.5796 in contrast to NGRU.It is concluded that CNGRU has higher accuracy and stability than NGRU and other recurrent networks for predicting the temperature of permanent magnet synchronous motors.It provides the technical guarantee to ensure the safe and stable operation of the motors.