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What is Static Var Generator (SVG) ?

Jul. 23, 2025

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In today’s increasingly complex power systems, maintaining power quality and system stability is more critical than ever. One advanced solution that is gaining momentum across industries is the Static Var Generator (SVG)—a next-generation reactive power compensation device designed to dynamically regulate voltage levels, improve power factor, and reduce harmonic distortion.


What Is a Static Var Generator?

A Static Var Generator, commonly abbreviated as SVG, is a power electronic device designed to provide fast and continuous reactive power compensation. It detects changes in load current and dynamically generates inductive or capacitive current to improve power factor, stabilize voltage and reduce phase imbalance.

Unlike conventional capacitor banks that operate through fixed compensation steps, an SVG provides stepless compensation and responds within milliseconds. This makes it particularly suitable for electrical systems containing rapidly changing loads such as welding machines, cranes, compressors, rolling mills, elevators, data centers and renewable energy equipment.

SinaVa SVG systems use IGBT-based converter technology and real-time digital control to support dynamic power factor correction across industrial, commercial and utility applications.

What is Static Var Generator (SVG) ?cid=4

Static Var Generator in Brief


QuestionQuick Answer
What does an SVG do?It dynamically generates or absorbs reactive current.
What problem does it solve?Low power factor, reactive power fluctuation, voltage instability and phase imbalance.
How fast does it respond?SinaVa SVG systems provide an overall response time of less than 10ms.
Can it compensate inductive and capacitive loads?Yes, the target power factor can be adjusted in both leading and lagging directions.
Is it suitable for fluctuating loads?Yes, SVG is particularly suitable for rapidly changing loads.
Can several modules operate together?Yes, modular SVG units can be connected in parallel for capacity expansion.


How Does a Static Var Generator Work?


A Static Var Generator continuously measures the voltage and current of the electrical system through external current transformers. Its digital controller calculates the amount and direction of reactive current required by the load.

The operating process can be summarized in four steps:

  1. Current Detection: Current transformers measure the load current in real time.

  2. Reactive Power Calculation: The controller identifies whether the load requires inductive or capacitive compensation.

  3. Current Generation: The IGBT-based converter generates the required compensation current.

  4. Grid Compensation: The compensation current is injected into the electrical system, bringing the load current closer in phase with the voltage.

When the load consumes inductive reactive power, the SVG supplies capacitive current. When the load produces capacitive reactive power, the SVG absorbs it. This bidirectional operation enables continuous power factor correction under changing load conditions.


SVG vs SVC vs Capacitor Bank


FeatureSVGSVCCapacitor Bank
Main FunctionDynamic reactive power compensationDynamic voltage and reactive power controlStepped power factor correction
Compensation MethodIGBT/VSC-based current controlThyristor-controlled reactors and capacitorsContactor or thyristor-switched capacitor steps
ResponseMillisecond-levelFastSlower, depending on switching method
Compensation OutputContinuous and steplessContinuous or semi-continuousFixed steps
Inductive CompensationYesYesNormally requires reactors
Capacitive CompensationYesYesYes
Performance at Low VoltageMaintains strong compensation capabilityDepends on system designOutput decreases as voltage falls
Risk of OvercompensationLow with correct control settingsLowHigher under rapidly changing loads
Installation FootprintCompact and modularGenerally largerCost-effective but requires capacitor stages
Best ApplicationRapidly changing or mixed loadsLarge industrial and utility systemsStable loads with predictable reactive demand

A capacitor bank remains a cost-effective option for stable loads. An SVG is more suitable when the load changes rapidly, compensation must be precise, or both leading and lagging reactive power occur. For large utility or heavy industrial systems, an SVC or higher-capacity STATCOM solution may be considered.


Advantages of Static Var Generator (SVG)


Static Var Generators offer several advantages over traditional methods of reactive power compensation, such as capacitor banks and reactors. Some of these advantages include:


Fast Response: Static Var Generators can respond rapidly to changes in the power system, making them suitable for compensating dynamic loads and disturbances.


Continuous Control: Static Var Generators provide continuous control over reactive power compensation, allowing for precise adjustment and improved power quality. When load is generating inductive or capacitive current, it makes the load current lagging or leading the voltage. SVG detects the phase angle difference and generates leading or lagging current in to the system, making the phase angle of current almost same as the voltage on the transformer side, this means fundamental power factor is near unity.


Voltage Stability: Static Var Generators help regulate voltage levels by injecting or absorbing reactive power, thus preventing voltage fluctuations, load imbalance and maintaining stable system operation. it provides instantaneous step-less reactive power compensation to solve the power quality problems caused by low power factor and harmonic currents produced by non-linear and highly dynamic fluctuating loads such as VFDs, cranes, welding machines, rolling mills, equipment in chemical industry, cement plants, sugar plants and textile units etc.


Harmonic Filtration: SVGs can be equipped with additional filters to mitigate harmonics and improve the overall power quality of the system. Hybrid systems comprising SVG and Thyristor switched filter bank feeders can be provided for a more cost effective solution for elimination of harmonic currents & voltages, power factor correction (lagging and leading), reduction of voltage variation (sags and swells), mitigate voltage fluctuation (flicker), and load balancing.


Compact Structure: Compared to traditional compensation methods, SVGs require less physical space, making them suitable for installations with space constraints. Compare prices.


Applications of Static Var Generator


SVGs are widely deployed in industries and environments that demand high power quality:

Manufacturing Plants: Compensating for inductive loads from motors and welding equipment

Data Centers: Maintaining voltage stability in sensitive electronic environments

Renewable Energy Systems: Stabilizing wind and solar power systems with intermittent outputs

Commercial Buildings: Improving power factor and reducing penalties from utilities

Electric Vehicle Charging Stations: Handling rapid load variations and improving grid interface


When Should You Use a Static Var Generator?


An SVG should be considered when an electrical system experiences one or more of the following conditions:

  • Power factor changes significantly during production cycles.

  • Capacitor banks frequently switch on and off.

  • The system contains welding machines, cranes, elevators or variable-speed drives.

  • Both inductive and capacitive reactive power occur.

  • Voltage fluctuation or flicker affects equipment operation.

  • Three-phase loads are significantly unbalanced.

  • Existing capacitor banks are exposed to harmonic resonance.

  • Available installation space is limited.

  • Power factor penalties continue after conventional compensation is installed.

  • Future load expansion requires a scalable compensation system.


Common Applications of Static Var Generators


IndustryTypical LoadsMain Power Quality Requirement
ManufacturingMotors, VFDs, welding equipmentDynamic power factor correction
Steel and MetallurgyRolling mills, arc furnacesReactive power and flicker control
MiningConveyors, crushers, hoistsVoltage stability and load balancing
Data CentersUPS systems, cooling equipmentStable voltage and reliable power factor
Commercial BuildingsHVAC, elevators, pumpsReduced reactive power demand
Renewable EnergySolar and wind invertersGrid voltage and reactive power support
EV ChargingHigh-power charging stationsFast compensation during load changes
Medical FacilitiesMRI, CT, X-ray and UPSStable power for sensitive equipment
Ports and CranesVariable lifting and drive loadsRapid compensation and flicker reduction


Why Choose SVG Over Traditional Solutions?


Dynamic Real-Time Compensation: Handles fast-changing loads without delay.


Improved Power Factor: Helps avoid utility penalties and reduces energy bills.


Voltage Stabilization: Mitigates voltage drops and flicker under peak load conditions.


Harmonic Suppression: Optional functionality can help clean up harmonic distortion.


Space-Saving Design: Modular and compact, easy to integrate into existing systems.


Choosing the Right SVG Solution


When selecting an SVG, consider:

· Load capacity and fluctuation levels

· Harmonic distortion levels

· Grid voltage stability requirements

· Available installation space

· Compliance with local grid codes and standards (e.g., IEEE 519, IEC 61000)


Modern SVG solutions offer scalable architectures that can be tailored to suit facilities of all sizes—from small commercial operations to heavy industrial plants.


Final Thoughts


As industries move toward smarter, cleaner, and more efficient energy systems, Static Var Generators are becoming essential components of modern power infrastructure. Their ability to stabilize voltage, regulate power factor, and respond instantly to load changes makes them a superior alternative to traditional reactive power compensation methods.


Why Choose SinaVa as Your Static Var Generator Supplier?


SinaVa Power is a professional Power Quality Solution Provider & Equipment Supplier, providing SVG systems for dynamic reactive power compensation, power factor correction, voltage support and load balancing.

Our available configurations include:

  • 220V, 400V and 480V systems

  • 15kVar to 150kVar module options

  • Wall-mounted, rack-mounted and floor-standing designs

  • Modular parallel capacity expansion

  • 3P3W and 3P4W electrical systems

  • RS485 and MODBUS-RTU communication

  • Inductive and capacitive reactive power compensation

  • Customized cabinet dimensions and colors

  • Technical selection and project configuration support

Send us your system data, single-line diagram or power quality report to receive a tailored SVG recommendation.


Ready to Improve Your Power Quality? Contact us today to discover how our advanced SVG solutions can help your facility optimize energy performance, avoid power factor penalties, and maintain grid compliance—efficiently and reliably.


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