Intelligent cycle switching control method of electronic capacitor

Abstract

The invention discloses an intelligent cycle switching control method of an electronic capacitor. Under the condition that the number of electronic capacitors switched is maintained unchanged, a control device controls to circularly switch the electronic capacitors in a passive dynamic compensation or passive intelligent compensation mode, so that each electronic capacitor can get full rest, and the condition of employing circular switching is in a way that the capacitor of each electronic capacitor is same. The output of each capacitor group in each phase is same, meanwhile, each capacitor group can get full rest, and thus, the electronic capacitor is prevented from being early damaged and is long in service lifetime and good in compensation effect.

Description

technical field [0001] The invention relates to a control method for a power capacitor, in particular to a control method for intelligent cycle switching of a power capacitor. Background technique [0002] Reactive power compensation improves the power factor of the user's electricity and prevents a large amount of reactive power from being transmitted over a long distance. It can reduce line loss, reduce voltage drop, improve power supply quality, and increase the effective output capacity of the transformer. The traditional reactive power compensation device is realized by switching the power capacitor through a mechanical switch, which cannot avoid the attenuation or even damage of the capacitance caused by the operation overvoltage, overcurrent impact, re-ignition of the opening arc, and harmonic amplification. Poor operation reliability and short service life; In addition to the above-mentioned factors affecting the service life of power capacitors, the fatal impact of ...

AI Technical Summary

Problems solved by technology

The traditional reactive power compensation device is realized by switching the power capacitor through a mechanical switch, which cannot avoid the attenuation or even damage of the capacitance caused by the operation overvoltage, overcurrent impact, re-ignition of the opening arc, and harmonic amplification. Poor operation reliability and short service life; In addition to the above-mentioned factors affecting the service life of power capacitors, the fatal impact of continuous long-term operation under overvoltage on the service life of power capacitors is often artificially ignored. According to statistics: at 1.03UN, 1.05UN, 1.1 Under UN for several hours of non-continuous operation, but must not be operated continuously for a long time at a voltage higher than its rated voltage, otherwise the actual service life and reliability of the power capacitor will be greatly shortened; long-term overvoltage in the power grid is still relatively common

Traditional low-voltage reactive power compensation devices cannot work in dusty and dirty environments, and are easily damaged when used outdoors, and cannot compensate for rapid changes and impact loads

[0003] In order to solve the above-mentioned problems, the non-contact electronic switch switching capacitors of thyristor valves have been used in the existing technology, which is called reactive power dynamic compensation device, which can solve all the above-mentioned problems. However, the existing operating products still have the following problems: The main problem: First, the temperature rises when the AC switch is running. Basically, it is equipped with a fan, and some are equipped with a constant temperature box, and even have the function of over-temperature exit operation, which not only increases the cost, but also increases the energy consumption. The reliability is reduced; the second is that the service life does not exceed that of traditional products, and it is easy to be damaged when strong interference or line failure occurs, and the problem of continuous long-term operation of power capacitors under overvoltage is not solved; the third is that the product cost is high and the selling price Difficult to be accepted by users, unable to promote the application