With the in-depth study of power quality problems, on the basis of years of research on steady-state (or quasi-steady-state) power quality problems such as harmonics, voltage deviation, voltage fluctuation and flicker and their treatment methods, more and more attention has been paid to transient power quality problems and their countermeasures, such as voltage sag and temporary rise, power supply temporary interruption, impact harmonic change, and a lot of results have been achieved.
In recent years, with the putting into use of T3 terminal, the scale of airport power grid continues to expand, resulting in a great increase in the number of fault points that may cause voltage temporary, and voltage sags become more and more frequent. The voltage sag causes a lot of harm to the airport power grid. although a voltage sag lasts only a few tens of milliseconds, it will protect and stop the baggage system, ladder and elevator display system of the terminal, which needs to be reset manually, which will bring about the interruption of operation. it may cause flight delays or even serious consequences that threaten the personal safety of passengers. In addition, most of the low-voltage incoming circuit breakers are equipped with loss-of-voltage tripping devices. when the power supply is restored, the low-voltage circuit breakers must be closed manually because of the wide installation area and large usage of the low-voltage circuit breakers in the airport power supply network. it also results in the consequence of restoring power supply for a long time.
Due to the randomness and contingency of voltage sags, the traditional manual recording method does not have comprehensive statistical data and can not accurately reflect the real-time information of voltage sags. The PS500 voltage sag monitoring device independently developed by Guangzhou Xuantong Electric Technology Co., Ltd. can capture the data information of voltage surge, sag and interruption in the power grid anytime and anywhere, and record it. Through the analysis of the measured data sent to the server by 4G, it can be judged that the event of voltage surge or voltage sag occurs, and the basic data can be provided for the power supply department to restrain the voltage sag in the power grid, so that the prevention and control plan can be made in a timely manner. reduce economic losses.
The following picture is a temporary drop waveform detected by PS500 in a terminal during the peak period of power consumption.