Static Var Generator Overview

The Static Var Generator (SVG for short), based on voltage type inverter principle, uses the isolated gate binary transistor (IGBT4) to control the value and phase of AC voltage of inverter, so as to serve the purpose of reactive and harmonic compensation. As the switching frequency of IGBT is very high (dozens of kHz), SVG can realize fast compensation for reactive load, and achieve very high compensation precision. 

SVG is currently the best solution in reactive power control filed. Compared with the traditional SVC represented by TSC, the regulation speed of SVG is faster (the response speed is within 5ms), its compensation precision is high (the power factor after compensation is over 0.99), the compensation method is flexible (SVG can compensate both inductive reactive power and capacitive reactive power), and SVG also has the function of active filtration of harmonic current.

Wall-mounted SVG	Rack type SVG Panel

SVG Specification

How SVG Works?

Static Var Generator is a power electronics-based device connected in parallel with the load that requires harmonics mitigation. SVG works as a controlled current source providing any kind of current waveform in real time.

When the load generates inductive or capacitive current, it makes load current lagging or leading the voltage. An SVG detects the pase angle difference and injects in real time leading or lagging current into the electric power systems, making the phase angle of the current almost the same as that of the voltage, bringing fundamental power factor to unity. 

SVG Benefits

■Multifunctional: Reactive power and imbalance compensation

■Excellent reactive compensation: High speed, Precise (-0.99≤Cosφ≤0.99), Step-less, Bi-directional (capacitive and inductance) compensation

■Excellent imbalance correction: Both negative and zero sequence, mitigates neutral current

■Wide input voltage & frequency range, adapts to tough electrical environment

■Low thermal loss (≤3% of rated SVG capacity), efficiency ≥ 97%

■High stability: Infinite impedance to grid, avoids harmonic resonance problem

■Flexible application: Modular design, embedded in standard or customized cabinet

■Easy installation and maintenance: Easy installation for SVG module replacement and expansion

■Wide capacity range: 50kvar~600kvar for a single cabinet, up to 10 cabinets in parallel

■Environmental adaptability: -10~50°C temperature, compatible with diesel generators

■Complete protection: Grid over/under voltage, SVG over current, over temperature, and others. All faults recorded inevent log, convenient for failure analysis.

SVG Application Field

■Electric Arc Furnaces – voltage stabilisation reduces tap-to-tap time and electrode consumption.

■Rolling Mills – elimination of voltage and harmonic distortions reduces reactive power demand and increases electrical system capacity.

■Mining and heavy industry – dynamic reactive power compensation stabilise the power system, especially on large motor start up, ensuring reliability of the power system.

■Wind and solar farms – meeting strict grid connection criteria by providing dynamic voltage control and voltage stability at the common coupling point (PCC).

■Renewables markets – including solar farms, wind farms, solar panel installations.

Following are typical application industries of Static var generator.