Application and research on improving accuracy of real-time power consumption calculation of multi-split air conditioners

In response to the key issues such as low accuracy, high hardware costs and large time synchronization errors in real-time power consumption calculation of central air conditioning systems, this paper proposes a software-hardware collaborative metering method based on clock synchronization and load/power matching computation. The method employs a multi-source time-keeping architecture combined with a high-priority NTP (network time protocol) dynamic compensation mechanism to maintain system clock synchronization error at the millisecond level (±5 ms). By integrating a hierarchical load/power fitting strategy, it utilizes high-precision sampling and low-frequency compensation algorithms for high-power loads such as compressors and outdoor fans, while employing experimental fitting formulas for low-power loads such as electronic expansion valves and drainage pumps, enabling coordinated calculation of distributed node energy consumption. The experimental validation demonstrates that under six typical application conditions and different indoor unit configurations (1 to 4 units), the power consumption calculation accuracy consistently exceeds 95%, with lower deviations from conventional electricity meter benchmarks significantly than those of the industry standards. This method requires no additional hardware costs, resolving key technical barriers in real-time energy consumption monitoring for multi-split systems. It provides reliable technical support for building energy saving and refined energy efficiency management of air conditioning systems, offering substantial engineering application value and broad commercial potential.