Product Search
Find the right transformer for your needs
Voltage Regulators
13 Series · 100 Models
Product Images
Images are for illustration purposes only
Voltage Regulators Overview
Automatic voltage regulators (stabilizers) keep output voltage within a tight tolerance despite fluctuating mains, using servo-motor correction and smart control circuits. QDTB offers single-phase (TND, JJW, SJJW) and three-phase (SBW, SVC, WJS) models from 0.5 kVA to hundreds of kVA, with +/-3% accuracy, sub-1-second response, and over 90% efficiency. Built-in over-voltage, over-current, and over-temperature protection suits office equipment, medical devices, industrial automation, and commercial power systems.
Available Series
TND Series
The TND series single-phase automatic voltage regulators use servo motor-driven variable transformer technology for precise voltage regulation in office, laboratory, and household applications.
SVC Series
The SVC series three-phase high-precision voltage regulators provide stable 380V/220V output from a fluctuating three-phase input, with fast response and low waveform distortion for precision equipment and CNC machines.
SBW Series
The SBW series three-phase automatic voltage regulators are high-capacity compensator type stabilizers for industrial three-phase power systems with wide input voltage range.
WJS Series
The WJS series contactless (thyristor/IGBT) voltage stabilizers regulate three-phase voltage without moving parts or carbon brushes, using solid-state semiconductor compensation for ultra-precise, wear-free regulation.
JJW Series
The JJW series single-phase purified power supplies combine voltage regulation with power line conditioning, providing clean and stable power for sensitive equipment.
SJJW Series
SJJW three-phase precision voltage regulators maintain 380 V ±1% output. 6-100 kVA, 280-430 V input, for precision industrial equipment.
DBW Voltage Stabilizers Series
DBW series single-phase compensating voltage stabilizers maintain a stable 220V output from a fluctuating 160–250V input, using a compensating transformer with servo-driven brush adjustment. Rated 5–100 kVA, they combine high accuracy (±3%) with strong overload capacity, making them suitable for larger single-phase equipment, laboratories, and residential or commercial power distribution.
TNS Three Phase Stabilizers Series
TNS series three-phase high-precision servo voltage stabilizers regulate a fluctuating 280–430V three-phase input to a stable 380V ±3% output, using servo-driven variable transformer technology. Rated 6–100 kVA for industrial machinery, CNC equipment, and three-phase installations requiring accurate voltage with fast correction.
Induction Voltage Regulators Series
Induction voltage regulators provide stepless, brushless voltage regulation by varying the relative position of stator and rotor windings, offering smooth control for large-capacity AC circuits. Rated 10–1000 kVA for 380V/6kV/10kV systems, used where continuous, wear-free voltage adjustment is required.
Oil-Immersed Voltage Stabilizers Series
Oil-immersed voltage stabilizers provide outdoor voltage regulation for distribution and industrial circuits, with oil-immersed cooling and corrosion-resistant construction for pole-mount or pad-mount outdoor installation. Rated 10–1000 kVA for 6/10/35 kV and 380V systems, maintaining stable output under fluctuating supply.
DBW Voltage Stabilizers Series
DBW series single-phase compensating voltage stabilizers maintain a stable 220V output from a fluctuating 160–250V input, using a compensating transformer with servo-driven brush adjustment. Rated 5–100 kVA, they combine high accuracy (±3%) with strong overload capacity, making them suitable for larger single-phase equipment, laboratories, and residential or commercial power distribution.
TNS Three Phase Stabilizers Series
TNS series three-phase high-precision servo voltage stabilizers regulate a fluctuating 280–430V three-phase input to a stable 380V ±3% output, using servo-driven variable transformer technology. Rated 6–100 kVA for industrial machinery, CNC equipment, and three-phase installations requiring accurate voltage with fast correction.
Instant Selection & Quote Calculator
Select your specifications to get an estimated price instantly.
More options(4)
Certification
Reference prices are for estimation only and do not constitute a formal offer.
3 · Get this quote
We will reply with your latest quote instantly.
Related Engineering Calculators
Free sizing and pricing tools for this product category.
Application Scenarios
Medical Devices
Stabilises supply for imaging and laboratory equipment sensitive to voltage fluctuation.
Office & IT Equipment
Protects computers, servers and peripherals from brownouts and surges.
Industrial Automation
Keeps CNC, PLC and robotics within tolerance in areas with unstable grids.
Telecommunications
Reliable voltage for base stations and transmission equipment.
Laboratories & Testing
Precise supply for instruments where measurement accuracy depends on voltage.
Residential & Commercial
Whole-building stabilisation in regions with frequent voltage swings.
Technical Advantages
High Accuracy
±3% regulation keeps output within equipment tolerance.
Fast Response
Correction in under 1 second, recovering from grid disturbances quickly.
Full Protection
Built-in over-voltage, over-current and over-temperature protection.
Servo Technology
Motor-driven autotransformer design for reliable, low-maintenance operation.
FAQ - Voltage Regulators
What is the difference between a voltage regulator and a UPS?
Is ±3% accuracy sufficient?
Should I choose single-phase or three-phase?
What is the minimum order quantity (MOQ) for Voltage Regulators?
What is the delivery time for Voltage Regulators?
Which standards and certifications do your Voltage Regulators comply with?
Related Product Categories
Dry Type Transformers
Dry-type transformers are essential components in modern ele
Oil Immersed Transformers
Oil-immersed transformers are the workhorse of power distrib
Special Isolation Control Transformers
Isolation and control transformers provide galvanic separati
Amorphous Alloy Transformers
Amorphous alloy transformers are the lowest-loss choice for
Box Type Substations
Box-type substations, also known as prefabricated substation
Reactors
Reactors are inductive components that shape power quality b
Cable Branch Boxes
Cable branch boxes are sealed distribution points that split
Ring Main Units
Ring main units (RMUs) are compact, sealed switchgear that f
High Voltage Switchgear
High-voltage switchgear performs switching, protection, and
Low Voltage Switchgear
Low-voltage switchgear and motor control centers (MCCs) deli
Single Phase Transformers
Single-phase control transformers provide galvanic isolation
Three Phase Transformers
Three-phase dry-type transformers step down, isolate, or ada
Variable Transformers
Variable auto-transformers deliver continuous, stepless AC v
Inverters
Pure sine wave inverters convert DC battery power (12 V/24 V
Dc Power Supplies
Switching DC power supplies convert AC mains into regulated
Battery Chargers
Intelligent battery chargers restore and maintain lead-acid
Motor Starters
Motor starters control three-phase motor energization with r
Ups
Online double-conversion UPS systems continuously regenerate
Power Capacitors
Self-healing power capacitors provide power factor correctio
Solar Pv Modules
Solar PV modules convert sunlight into direct current and ar
String Inverters
String grid-tie inverters turn the DC output of PV modules i
Hybrid Inverters
Hybrid solar inverters combine a grid-tie inverter and a bat
Energy Storage Batteries
Energy storage batteries store surplus solar or off-peak pow
Pcs Energy Storage
Power conversion systems (PCS) are the bidirectional heart o
Battery Management Systems
The battery management system is the safety and intelligence
Ess Fire Suppression
Fire suppression for energy storage must act in the seconds
Pv Mounting Structures
Mounting structures hold the array to the roof or ground for
Dc Cables Connectors Spd
The DC side of a PV plant is only as reliable as the cables,
Monitoring Scada Communication
A solar or storage plant that cannot be observed and control
Cables Trays Grounding
The AC side and the structural grounding of a plant are easy
Energy Storage Containers
The energy storage container packages battery, power convers
Busway
Busway (bus duct) systems distribute high-current power from
Ev Charging Stations
EV charging stations supply electric vehicles with AC Level
Pole Mounted Switchgear
Pole-mounted switchgear provides outdoor switching, protecti
Svg Svc
Static Var Generator (SVG) and Static Var Compensator (SVC)
Active Harmonic Filters
Active Harmonic Filters (APF), also called active power filt
Ats Transfer Switches
Automatic Transfer Switches (ATS) automatically transfer the
Diesel Generators
Diesel generator sets provide reliable prime or standby powe
Eps Emergency Power
EPS (Emergency Power Supply) systems provide battery-backed
Wind Turbines
QDTB onshore wind turbines span the 2 MW, 3 MW and 5 MW clas
Scada Automation
Substation SCADA and secondary automation equipment for MV/L
American Pad Mounted Transformers
American pad-mounted transformers (ZGS series) place a 12 kV
Need help?
All specifications and dimensions can be customized upon request
Servo-Motor AVR vs Electronic Stabilizer vs Induction Regulator: How to Choose
| Servo-Motor AVR (TND/SBW) | Electronic SVC Stabilizer | Induction Regulator | |
|---|---|---|---|
| Correction method | Motor moves a carbon brush along the winding | Thyristor-switched taps correct in steps | Magnetic coupling between rotor and stator |
| Accuracy | Tight tolerance held across the full input band | Good tolerance, with a small step ripple | Holds the output with no moving parts at all |
| Response | Fast enough for commercial and industrial loads | Fast, because nothing has to move mechanically | Smooth and continuous, with no brush wear |
| Waveform | Output follows the input waveform | Switching adds a little distortion | Output stays sinusoidal |
| Wear parts | Carbon brush and servo motor need periodic service | No moving parts, so no brush maintenance | No brush, but the machine is larger and heavier |
| Efficiency | High at ratings well below full load | High across the input band | Lower, since the machine stays magnetised |
| Typical application | Office, medical and industrial automation loads | Small and medium commercial installations | Utility and heavy industrial voltage control |
Where QDTB® Voltage Regulators Are Specified
Voltage regulators are specified wherever the mains is too wide for the load to tolerate: medical devices, office and IT equipment, laboratories and telecom sites on feeders with a weak or overloaded supply. The unit holds the output inside a tight band while the input swings, so the load sees a nominal voltage rather than the grid's worst day.
Industrial automation panels use the three-phase models ahead of a group of drives and PLC supplies, because a stable input is cheaper than over-specifying every power supply behind it. Single-phase units handle individual equipment or a single office floor where the load is not balanced across three phases.
A regulator is not a substitute for a UPS: it corrects voltage while mains is present, and the load still drops when the supply fails. Where the process cannot tolerate an outage, the regulator and the UPS are specified as two separate devices, each doing its own job.
The range runs from 0.5 kVA to hundreds of kVA with ±3% accuracy, sub-1-second response and over 90% efficiency. Over-voltage, over-current and over-temperature protection are built in, so a sustained mains fault trips the regulator instead of passing through to the load.
Frequently Asked Questions
What is the difference between a voltage regulator and a UPS?
A regulator corrects voltage fluctuation but needs mains present. A UPS provides battery backup during outages. For critical loads, use both.
Is ±3% accuracy sufficient?
Yes for most industrial and office equipment. Precision instruments needing tighter regulation may require a stabilised supply.
Should I choose single-phase or three-phase?
Match the load. Single-phase (TND) for individual equipment, three-phase (SBW/SVC) for three-phase machinery and whole installations.
What is the minimum order quantity (MOQ) for Voltage Regulators?
One unit for standard products. Custom-designed equipment is quoted on specifications — send your parameters or drawings and our sales team will confirm the MOQ for your configuration.
What is the delivery time for Voltage Regulators?
Standard units are delivered in 30-45 days. Custom or large-capacity units follow a project-specific schedule confirmed at quotation. Rush orders can be accommodated for urgent projects.
Which standards and certifications do your Voltage Regulators comply with?
Each unit is designed to the IEC, IEEE or GB standard your project specifies. All QDTB® equipment is ISO 9001 certified and CE marked, and the company operates ISO 9001, ISO 14001 and ISO 45001 management systems.