Lightweight Real-Time power quality disturbance recognition using Time-Frequency fusion with Cross-Attention mechanism

INTRODUCTION: Accurate power quality disturbances (PQDs) classification is critical for maintaining grid stability and reliability in modern power systems. However, existing deep learning methods predominantly rely on single-domain feature extraction, limiting their discriminative capability for complex composite disturbances under noisy conditions. This study addresses these limitations by proposing a dual-pathway architecture that synergistically integrates time-domain and frequency-domain representations through cross-attention fusion. OBJECTIVES: This work aims to develop a robust PQDs classification framework capable of accurately identifying 24 disturbance classes, including complex composite types, while maintaining high noise immunity and computational efficiency for real-time monitoring applications. METHODS: A dual-pathway deep learning architecture is proposed, comprising parallel CNN-BiLSTM branches for time-domain temporal modeling and FFT-based frequency-domain spectral analysis. A cross-attention mechanism dynamically fuses complementary features from both pathways. The model is trained and evaluated on a comprehensive dataset containing 24 PQDs classes under multiple noise levels. RESULTS: The proposed model achieves 99.73% accuracy on the validation set and maintains 98.94% accuracy under 30dB noise conditions. Ablation studies confirm the dual-pathway structure improves accuracy by 6.51 percentage points over single-branch variants, while the cross-attention mechanism contributes an additional 2.08 percentage points. The model converges within 43 epochs with inference latency of 251μs per sample, satisfying real-time requirements. CONCLUSION: The proposed dual-pathway cross-attention architecture demonstrates superior performance in PQDs classification, effectively balancing accuracy, noise robustness, and computational efficiency. This approach provides a viable solution for intelligent power quality monitoring in practical smart grid applications.