In order to improve the power quality of the power grid, it is necessary to accurately detect and analyze the power quality, measure the power quality of the power grid, analyze and judge the causes of various power quality problems, so as to provide the power quality of the power grid.
The nonlinear problem of power supply system components is the harmonic generated in the normal operation of the generator, the harmonic generated by the voltage transformation equipment of the power grid, the harmonic generated by DC transmission, and the expansion of harmonics by high-voltage transmission lines. In addition, the setting of shunt capacitor in substation and other factors will also produce high-order harmonics. Among these factors, DC transmission is the main factor of harmonic generation in power system.
The on-line power quality monitoring device can implement on-line continuous monitoring for important substations or distribution points of important power users. Online monitoring is mainly applicable to monitoring the voltage quality deviation, three-phase voltage imbalance, voltage harmonic and other states of the power grid, as well as the harmonic current and negative sequence current injected into the public power grid by the power user load.
The power quality solution can be understood as forming a closed-loop system from monitoring to governance and then to monitoring, and providing human-computer interaction interface through the power quality online monitoring system to manage the whole monitoring and governance system.
The power quality monitoring device can monitor whether the power quality meets the requirements of safe power supply. When a safety accident is caused due to power quality, it can provide the basis for post analysis and decision-making for power quality management.
For the main power quality problem: harmonic problem, provide a tool for harmonic control: active power filter.
Continue on-line monitoring of power quality, especially the effect of harmonic control, to avoid safety accidents.
