50-800kvar Static Var Generator(SVG) for Power Factor Correction(PFC)

Overview

With the rapid development of science and technology, power electronics technology is constantly updated and widely used in various scenarios. The requirements for power quality of power systems are increasing day by day. Traditional reactive power compensation methods can no longer fully meet the use requirements of scenarios such as impact loads. The new compensation equipment - Static Var generator (SVG) has achieved a revolutionary breakthrough in power quality optimization by adopting fully controlled semiconductor devices and grid-connected reactors. The SVG controller can detect the load current in real time, and through advanced current decomposition algorithms and control algorithms, it can achieve real-time bidirectional reactive power compensation (100% inductive ~ 100% capacitive) and imbalance management, accurately solving power quality problems such as voltage sag, harmonic pollution, and low power factor in industrial power grids. As a core power quality management device, SVG can not only dynamically track load changes, but also actively generate or absorb reactive power, quickly increase the power factor to above 0.95, and effectively suppress the imbalance of three-phase current, significantly improving the stability of the power grid.

Working Principle and Mode of SVG

SVG working principle

Based on the high power converter, the core is the voltage-type inverter, and the DC side uses DC capacitance as energy storage elements to provide voltage support. In operation, it is equivalent to a three-phase AC power supply with adjustable voltage, phase and amplitude.

The normal operation of the inverter depends on the voltage support of the DC side. When the inverter is connected into the AC power supply, each IGBT reverse freewheeling diode forms a rectifier to charge the DC capacitor. After normal operation, the energy storage of the DC capacitor will be used to satisfy the internal loss of the inverter, and the capacitor voltage will drop, the capacitor must be continuously charged to keep the voltage within the working range. Through changing the amplitude of the inverter output voltage to achieve the purpose of emitting or absorbing reactive power.

SVC VS SVG

Compared to the first and second generation of reactive power compensation, the third generation Static VAR Generator (SVG) has outstanding advantages :

1.Comprehensive optimization of power quality: through dynamic reactive power compensation, harmonic content is reduced and power supply reliability is improved;

2.Fast response speed: under the drive of fully controlled devices, the response time can be controlled within 5 milliseconds to adapt to high-frequency load changes;

3.Two-way compensation capability: it can compensate for both inductive and capacitive reactive power, and flexibly adapt to complex scenarios such as photovoltaic grid connection and arc furnace;

4.Intelligent management: supports docking with smart grids to achieve remote monitoring and real-time analysis of power quality data.

SVG Application

Technical Parameters

SVG Common Specification Selection Table

Schematic diagram of SVG module structure