Induction motors play a vital role in the cooling water supply system of hydropower facilities. However, it is unrealistic to collect suffi-cient fault samples in hydropower station. The scarcity of labeled samples poses a challenge in developing a powerful diagnostic model with high classification accuracy. To address this challenge, this paper proposes a multi-channel data fusion strategy based on Trans-former for feature enhancement. Initially, original signals are transferred into non-overlapping single-channel data patches to preserve correlation features across different channels. Then, temporal and spatial attention modules are applied to process the data patches, which can learn and fuse temporal and spatial information, respectively. Subsequently, the data patches are embedded to retain posi-tion information and represent fault-related features through class embedding, which are further processed by a Transformer encoder with self-attention mechanisms. Finally, the classification task is achieved by utilizing a multilayer perceptron layer connected to the class embedding. In facing up with limited training samples, the proposed method could learn robust features that are beneficial to improve the fault diagnosis ability of induction motor. The proposed method is compared with three basic models and two improved methods, demonstrating the superiority of the proposed method in accuracy and feature clustering performance with limited sample conditions. Additionally, the ablation experiment demonstrates the necessity of each module in the proposed method.