Development of an AI based Building Harmonics Load Tracer

The problem of power harmonics now becomes the No. 1 headache in commercial buildings in Hong Kong, particularly more serious in those high-rise commercial buildings. International as well as local requirements have been adopted to set limits on the power harmonics level, beyond which harmonics mitigation measures are to be implemented. The applicants carried out consultancy projects in the past to find out the causes of accidental explosion of power factor correction capacitor banks and combustion of overloaded cables while all pointed to the same cause, harmonics pollution. The present solutions to power harmonics problems are mainly installation of power quality monitoring devices in standalone manner or networked for continuous power quality monitoring, and the use of passive or active harmonic filters. As the power harmonic profiles of a commercial building is dynamically changing due to load variations, occupational changes and changes in system configurations, any harmonics filtering scheme has to be modified from time to time. A networked power quality monitoring system is therefore deemed necessary which can be integrated with the building management system for continuous monitoring. By the way, it is also the top responsibility of a facility manager to find out the tenant who pollutes the power distribution system with harmonics, which is not a piece of easy job.The questions in practice are how to optimize the configuration of a networked power quality monitoring system so as to select and install power harmonics filters of optimal sizes and at optimal locations, and to find out the chief offender, i.e. the source of pollutants. That requires knowledge of the origin and distribution of harmonics, and the decomposition of a combined harmonics spectrum into individual patterns caused by individual non-linear loads. With all such information in mind, it is possible to draw a full harmonics distribution map of the whole power network with details down to every point of common coupling. As a beginning, the scope of the project will be confined to a typical office environment.