Reactive power compensation device
Measures to improve power quality involve a wide range of aspects, including reactive power compensation, harmonic suppression, voltage fluctuation and flicker reduction, and three-phase imbalance.
Devices used for reactive power compensation and harmonic control, such as passive power filter, have both reactive power compensation and voltage regulation functions, and are generally designed according to the parameters of harmonic source, electrical characteristics of installation point and user requirements; static reactive power compensation device (SVC) device is an important equipment for comprehensive control of voltage fluctuation and flicker, harmonic and voltage imbalance. Active power filter (APF) is a new type of power electronic device which can dynamically suppress harmonics and compensate reactive power. It can compensate the harmonic and reactive current with varying frequency and amplitude. It is mainly used in low-voltage distribution system.
The development of reactive power compensation technology has experienced several different stages from synchronous condenser to switching fixed capacitor to static var compensator (SVC) to the attractive static var generator SVG (STATCOM).
According to the different structure and principle, SVC technology can be divided into self saturating reactor type (SSR), thyristor phase controlled reactor (TCR), thyristor switching capacitor type (TSC), high impedance transformer type (TCT) and excitation control reactor type (AR).
With the development and improvement of power electronic technology, especially high-power turn off device technology, a more advanced static var compensation device (SVG) is still being developed at home and abroad. Although they are still in the stage of development and trial operation, they have not yet been commercialized, but with its superior performance characteristics, svg can be applied in power system It will be used more and more widely.
Feature editor
The characteristics of various reactive power equipment are as follows:
1) Synchronous condenser: slow response speed, high noise, high loss, obsolete technology, belongs to obsolete technology;
2) Switching fixed capacitor: slow response compensation mode, poor continuous controllability;
3) Static var compensator (SVC): relatively advanced and practical technology, it has been widely used in power transmission and distribution system;
4) Static var generator SVG (STATCOM): although it has technical limitations and belongs to a few demonstration projects, SVG is a more advanced new type of static var compensation device. It is an important part of flexible AC transmission system (FACTS) technology and custom power (CP) technology, and the development direction of modern reactive power compensation device.