SVG Dynamic Reactive Power Compensation Device

1. Product Overview

SVG (Static Var Generator) is a new-generation static reactive power compensation device and a representative product in the field of reactive power compensation technology. Connected in parallel to the grid, SVG acts as a variable reactive current source. By adjusting the amplitude and phase of the AC output voltage of the inverter, or by directly controlling the amplitude and phase of its AC-side current, it rapidly absorbs or emits the required reactive power to achieve fast dynamic reactive power regulation. With direct current control, it can not only track and compensate the inrush current of impact loads, but also track and compensate harmonic currents. Using power electronic inverter technology, it generates a current of equal magnitude and opposite direction to the compensated object, canceling each other out, and the power factor can approach 1.

2. Key Selling Points

· Stepless Precise Compensation: Stepless regulation starting from 0.1 kvar, replacing the traditional 3-10 level stepped capacitor compensation, raising power factor above 0.98.

· Millisecond Response: Controller response time ≤ 1 ms; one compensation cycle completed in 1-20 ms, completely eliminating reverse reactive power delivery.

· Bidirectional Continuous Regulation: Both emits and absorbs reactive power, dynamically following load changes with continuous full-range capacitive and inductive regulation.

· Harmonic-Resistant, No Amplification: Controlled current source design compensates only fundamental reactive power; it neither generates nor amplifies harmonics, and can dynamically filter them.

· Efficiency ≥ 98%: Extremely low self-loss, service life over 10 years, and virtually maintenance-free.

· Wide Voltage Range: Full series from 0.38 kV low-voltage to 6 kV / 10 kV / 35 kV medium-high voltage, with drawer, wall-mount, and cabinet installation options.

3. Product Features

· Harmonic-resistant design for enhanced system safety. As a controlled current source, SVG compensates only fundamental reactive current; harmonic currents do not damage the compensation device, extending service life and reducing maintenance. It also avoids harmonic amplification that may occur with capacitor-reactor banks, preventing damage to other system equipment from harmonic overvoltage;

· Dynamic continuous smooth compensation with faster response provides better compensation for voltage flicker. SVG follows load changes and dynamically compensates power factor continuously, capable of both emitting and absorbing reactive power, completely eliminating reverse reactive power delivery;

· Capable of resolving load unbalance problems;

· Not only does not generate harmonics, but also dynamically compensates harmonics while compensating reactive power;

· Current-source characteristics: output reactive current is not affected by bus voltage; with impedance characteristics, output current decreases linearly with bus voltage;

· No transient impact during switching, no inrush current, no arc restrike, and can be re-energized without discharging;

· Low maintenance and low operating cost;

· Easy installation, configuration, and commissioning with a clear user interface.

4. Working Principle & Model Description

4.1 Working Principle

The basic principle of SVG is to connect a self-commutated bridge circuit in parallel to the grid through a transformer or reactor. By appropriately adjusting the amplitude and phase of the AC-side output voltage of the bridge circuit, or by directly controlling its AC-side current, the circuit can absorb or emit the required reactive current, achieving dynamic reactive power compensation.

By adjusting the relationship between the converter output voltage Vc and the system voltage Vs, three operation modes are realized:

· No-Load Operation Mode: When Vs = Vc, the compensation current Ics = 0, and the device outputs no reactive power.

· Capacitive Operation Mode: When Vc > Vs, Ics is a leading current, and the device acts as a capacitor, emitting reactive power.

· Inductive Operation Mode: When Vc < Vs, Ics is a lagging current, and the device acts as a reactor, absorbing reactive power.

4.2 Model Description

Model format: SVG - Capacity - Installation Type / Voltage Level

· Capacity (kvar): 20 / 30 / 50 / 75 / 100 / 200, etc.

· Installation type: C (Drawer), B (Wall-mount), G (Cabinet)

· Voltage level: 0.38 kV (LV), 6 kV, 10 kV, 35 kV (MV/HV)

5. Comparison with Traditional Capacitor Compensation

6. Applications

6.1 Typical Industries

· Metallurgy, steel, welding and other impact-load industries

· Petroleum, chemical, mining and other continuous-production enterprises

· Automotive manufacturing, machining and other automated production lines

· Data centers and IDC facilities

· Renewable energy stations (PV, wind, energy storage)

· Rail transit, ports and terminals

· Commercial complexes, hospitals, stadiums and other critical loads

6.2 Typical Problems Solved

· Low power factor resulting in utility penalties

· Large load fluctuations causing severe voltage flicker

· High harmonic content affecting normal equipment operation

· Three-phase unbalance causing equipment heating and increased losses

· Frequent switching of traditional capacitor banks with high maintenance cost

· Large reactive power fluctuations at renewable energy grid-connection points causing voltage instability

7. Customer Value

· Improve Power Factor, Avoid Penalties: Power factor stabilized above 0.98 after compensation, completely eliminating power factor penalties and qualifying for electricity bill rewards.

· Reduce Line Losses, Save Energy: Local reactive power balance reduces reactive current in lines and transformers, lowering losses and saving electricity costs.

· Improve Power Quality: Dynamically suppresses voltage flicker, filters harmonics, and balances three phases, extending equipment life and reducing downtime.

· Reduce O&M Cost: Over 10-year service life, virtually maintenance-free, no need for periodic capacitor and contactor replacement.

· Enhance System Stability: Millisecond-level response rapidly suppresses voltage fluctuations, ensuring stable operation of sensitive equipment.

8. Technical Specifications