3 Phase 20kVA Servo Motor AVR

Competition in modern manufacturing is largely a contest of Overall Equipment Efficiency (OEE). Among the many factors influencing OEE, power quality is frequently overlooked, yet it is often a primary culprit behind unplanned downtime.

Voltage sags can disrupt PLC control programs and trigger alarm shutdowns in servo drives; sustained high voltage accelerates motor insulation aging and shortens the lifespan of VFD DC-bus capacitors; and three-phase imbalance causes motor torque ripple, compromising machining precision.

Compared to entry-level 10KVA or intermediate 15KVA models, the 3 Phase 20KVA Servo Motor AVR not only handles the high inrush currents (typically 5–7 times the rated current) associated with starting inductive loads like motors and compressors, but also—thanks to its independent three-phase regulation rapidly restores voltage balance across phases during sudden single-phase load fluctuations, ensuring the entire production line remains undisturbed.

Product Parameter

What are the advantages over other products?

In terms of system compatibility, the 20KVA capacity corresponds to a rated current of approximately 30A (3-phase 380V), making it a perfect match for the vast majority of 40A (or lower) circuit breakers and contactors on the market, eliminating the need for costly power distribution cabinet upgrades.

Furthermore, the 3-Phase 20KVA Servo Motor AVR shares the exact same dimensions (500×380×670mm) and weight (82kg) as the 10KVA and 15KVA models. This consistency in footprint and structural load requirements allows customers to upgrade to a higher capacity without altering their existing layout, while simultaneously securing sufficient power headroom to accommodate the addition of one or two more machines in the future.

The 3 Phase 20KVA Servo Motor AVR inherits the inherent advantages of the servo-motor structure: high impact resistance, freedom from the risks associated with fragile power electronics, and low-cost, easy carbon brush replacement. Equipped with an intelligent temperature-controlled fan and a multi-layer protection system, this model is designed for continuous 24-hour, three-shift production environments, making it particularly suitable for assembly line operations that demand high power supply continuity.

Key Features

1. Optimal Capacity Positioning

The 20KVA rated power precisely fills the market gap between 15KVA and 30KVA models. For load groups with a total installed capacity of approximately 15–18KW, the 20KVA unit provides a reasonable 10%–15% margin. This allows it to easily handle motor startup surges while avoiding the inefficiency of operating in a light-load zone due to excessive capacity, ensuring the stabilizer consistently runs within its peak efficiency range (60%–80% load).

2. Ensuring Production Continuity

It features a wide input voltage tolerance of ±20%; the stabilizer maintains a stable output even when grid voltage drops to 304V or spikes to 456V. With a response time of less than one second, it effectively mitigates voltage flickers during thunderstorm seasons and voltage fluctuations caused by the switching of heavy equipment, minimizing the risk of power supply interruptions.

3. Independent Three-Phase Regulation

Designed for factory scenarios involving mixed loads—such as single-phase lighting and outlets alongside three-phase power equipment—it utilizes independent phase sampling and control technology. Even with significant load imbalances across phases, it stabilizes each phase voltage within the required precision range, preventing damage to precision control boards caused by overvoltage resulting from neutral point shifts.

4. High-Durability Design

Constructed with industrial-grade Class A insulation materials, it withstands AC 2000V/1min without dielectric breakdown. With a net temperature rise of <60°C and a built-in intelligent forced-air cooling system, it operates stably over the long term in ambient temperatures of -5°C to 40°C and humidity levels below 90%, making it suitable for high-temperature, high-humidity environments such as injection molding workshops, foundries, and underground power distribution rooms.

5. Modular Maintenance

Carbon brushes are the only consumable parts; replacement is simple and low-cost (no need to disassemble the entire unit). The control board utilizes plug-in terminal connections, significantly reducing troubleshooting and repair times. The unit has a design lifespan exceeding 15 years, resulting in a long-term total cost of ownership far lower than that of electronic voltage stabilizers.

6. Plug-and-Play

Features standard three-phase four-wire wiring (A/B/C/N/PE) and supports dual-frequency operation (50/60Hz). 3 Phase 20KVA Servo Motor AVR is compatible with diesel generator sets, UPS systems, and the input stages of various variable frequency drives (VFDs). A digital LED panel provides an intuitive display of phase voltages, facilitating quick on-site inspections.

Product Applications

1. Small and Medium-sized Manufacturing Lines: Provides stable power for CNC lathes, milling machines, machining centers, small stamping lines, and automated assembly lines, ensuring machining precision and maintaining production cycle times.

2. Large Building Power Equipment: Suitable for main elevator banks, central air-conditioning chiller units, fire pumps, and ventilation systems in high-rise office buildings, shopping malls, and hospitals; prevents elevator entrapment or protective shutdowns of cooling systems caused by voltage fluctuations.

3. Packaging and Food Machinery: Offers voltage stabilization protection for equipment that undergoes frequent start-stop cycles—such as pillow packaging machines, filling machines, sealing machines, and ovens—thereby extending the service life of contactors and motors.

4. Laser and Sheet Metal Processing: Supplies clean power to the CNC control units and auxiliary gas pumps of laser and plasma cutting machines, preventing high-voltage breakdown or cutting quality issues.

5. Communication Aggregation Rooms: Deployed at the input stage of switching power supplies and precision air conditioning units in regional aggregation rooms and edge data centers to prevent communication equipment downtime caused by voltage anomalies.

6. Testing and Inspection Equipment: Provides a stable voltage reference for environmental test chambers, dynamometers, and high-power charge/discharge testers in university laboratories and quality inspection centers, ensuring the repeatability of test data.

Customization Services

KTAC supports OEM/ODM services, including customization of exterior colors, packaging methods, input/output voltage ranges, and special function modules (such as EMI filters, lightning protection devices, and RS232/RS485 monitoring interfaces). Please contact us for a customized solution.

FAQ

1. How do I determine if my equipment requires 20kVA instead of 15kVA?

Calculate the total power (kVA) of all simultaneously operating equipment and account for the starting surge current of the largest single motor. If the total operating power falls between 12kVA and 15kVA—and involves large motors or equipment that starts and stops frequently—we recommend the 20kVA model to ensure sufficient headroom. If the total power remains consistently below 10kVA, the 15kVA model is sufficient. We can provide a free load calculation worksheet.

2. Will there be issues if the 20kVA voltage stabilizer operates at a low load for an extended period?

No. The SBW series utilizes servo-motor voltage regulation and does not have the "minimum load" requirement found in electronic voltage stabilizers. Even at light loads of 20%–30%, efficiency remains above 90%, and lower temperature rise actually helps extend the lifespan of the carbon brushes and the transformer.

3. Can independent three-phase regulation completely resolve three-phase imbalance issues?

Yes. The 3 Phase 20KVA Servo Motor AVR performs voltage sampling and compensation regulation for each phase individually, stabilizing each phase's output voltage to within ±3% accuracy. However, please note that it regulates voltage rather than active power distribution; if the three-phase load current is severely unbalanced (e.g., a difference of over 50%), we recommend optimizing the load distribution.

4. How does the equipment's bypass function work?

In the event of internal overload, short-circuit, overheating, or component failure, the control circuit automatically switches the load to the mains bypass circuit. At this point, the unit acts merely as a conductor; while voltage regulation is disabled, continuous power supply to the downstream equipment is maintained. Simultaneously, the panel triggers an audible and visual alarm to alert maintenance personnel.

5. How often do the carbon brushes need to be replaced?

Carbon brush lifespan depends on the frequency of voltage fluctuations and the magnitude of the load current. Under standard operating conditions with average grid quality, the normal service life is approximately 3 to 5 years. We recommend replacement when significant output voltage fluctuations are observed or when the brush has worn down to one-third of its original length. Replacement is simple and can be completed within 15 minutes.

6. Can units be connected in parallel to increase capacity? 

Connecting the outputs of two SBW voltage stabilizers directly in parallel is not recommended. If higher power output is required, it is advisable to select an SBW-30K, SBW-50K, or higher-rated model, or to contact us for a custom high-capacity centralized voltage stabilization solution.