A Comparative Analysis of Time Synchronization Techniques for a Hybrid Multi-Rate Power Monitoring System
Received: 11 September 2025 | Revised: 3 October 2025 | Accepted: 14 October 2025 | Online: 8 December 2025
Corresponding author: Ngo Phuong Le
Abstract
This study presents a comparative analysis of time synchronization methodologies for a hybrid distributed power measurement system, specifically engineered to facilitate the creation of a high-resolution Non-Intrusive Load Monitoring (NILM) dataset for Vietnam. The system architecture employs a multi-rate approach, combining high-frequency (6.99 kHz) waveform sampling for transient event detection with low-frequency (~1 Hz) power monitoring for appliance state tracking. The primary technical challenge addressed is the achievement of microsecond-level time synchronization across distributed low-cost Internet of Things (IoT) nodes without resorting to specialized, high-cost timing hardware. Four distinct synchronization architectures are evaluated, from a baseline Internet-based Network Time Protocol (NTP) approach to a proposed software-generated Pulse Per Second (PPS) trigger mechanism. The performance of each method is rigorously assessed based on a synthesis of data from established literature and technical benchmarks, focusing on critical metrics including synchronization accuracy, temporal jitter, per-node deployment cost, and implementation complexity. The analysis validates that the proposed software-generated PPS trigger, orchestrated by an NVIDIA Jetson Nano edge computer, provides an optimal balance between these competing factors. It achieves microsecond-level synchronization accuracy (50-200 µs jitter) sufficient for high-fidelity NILM applications, while maintaining a low-cost hardware profile essential for scalable academic research.
Keywords:
NILM, time synchronization, PPS, IoT, JetsonDownloads
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Copyright (c) 2025 Ngo Phuong Le, Nguyen Binh Khanh, Luong Ngoc Giap, Truong Nguyen Tuong An, Bui Tien Trung
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