3 Phase 50kVA Servo Motor AVR

Modern factories and large commercial facilities are filled with a large number of nonlinear loads: frequency converters, servo drives, UPS, switching power supplies, LED lighting drivers, etc. They generate a large amount of harmonic current (mainly 5th, 7th, and 11th harmonics) during operation.

These harmonics not only exacerbate the heat generation and loss of the voltage stabilizer itself, but more seriously, they will be injected back to the power grid, causing additional temperature rise in the transformer windings, overload heating of the neutral line, overcurrent breakdown of the reactive power compensation capacitor bank, and even causing the main switch of the incoming line to trip erroneously.

Moreover, the imbalance of three-phase loads will lead to neutral point drift, causing deviations of the three-phase voltage on the low-voltage side of the power distribution room to varying degrees, affecting the power quality of all users on the entire bus.

3 Phase 50KVA Servo Motor AVR is not a simple electromagnetic voltage regulation device:

1. Bidirectional electrical isolation: Through compensating the electromagnetic coupling of the transformer, SBW-50KVA forms a natural electrical isolation layer between the input and output, effectively weakening the lightning surge and voltage spikes from the power grid side that invade sensitive downstream equipment, and suppressing the reverse injection of harmonic current from the load side to the power grid side.

2. Three-phase independent decoupling regulation: Each phase has an independent sampling, control, and servo drive circuit. Even if the load at the rear end is severely unbalanced (for example, phase A is connected to a large number of single-phase lighting and office equipment, while phases B and C are connected to three-phase power), the voltage stabilizer can stabilize the three-phase output voltage within the accuracy range, thereby eliminating the problem of asymmetric bus voltage caused by neutral point drift and reducing the loss on the low-voltage side of the transformer.

3. High tolerance and anti-shock performance: Different from the electronic scheme that relies on IGBT/SCR for chopping regulation, this product adopts electromagnetic induction servo regulation, does not generate switching frequency harmonics, and the output waveform distortion rate is less than 0.1%. At the same time, its transformer and carbon brush components have extremely high short-term heat resistance, which can calmly cope with the surge impact of several times the rated current during the startup of large compressors, fans, and presses, and will not easily trigger overcurrent bypass protection like electronic equipment.

4. System-level monitoring and interconnection: The product is reserved for RS485 communication interfaces and dry contact alarm signals, which can be seamlessly integrated into the factory energy management system (EMS) or power monitoring system (SCADA), enabling real-time remote monitoring of key parameters such as input/output voltage, load current, and internal temperature, and supporting interconnection with front-end circuit breakers, ATS dual power supply switching cabinets, and building a complete intelligent power supply guarantee system.

Product Parameter

Key Features

1. Bidirectional Electrical Energy Purification

By leveraging the electromagnetic isolation characteristic of the compensation transformer, it effectively blocks the reverse transmission of harmonics (especially 5th, 7th, and 11th harmonics) from the load side to the power grid, reducing the failure risks of transformers and reactive power compensation devices; at the same time, it suppresses voltage flicker and surge impact on the power grid side, providing a pure power supply for precision loads.

2. Three-phase Independent High Precision Regulation

Using phase-by-phase independent sampling and control technology, each phase voltage is separately detected and compensated. Even if the three-phase load current is severely unbalanced (imbalance degree > 30%), the output three-phase voltage can still remain within ±3% under normal conditions, fundamentally eliminating the safety hazards and additional losses caused by neutral point drift.

3. Strong Short-Term Overload Capacity

Based on the electromagnetic induction working principle, it has a natural overload margin and can withstand short-term (≤ 5 seconds) over 8 times the rated current startup shock, especially suitable for frequent start-stop impact loads such as large power frequency converters, medium frequency furnaces, and large lifting equipment.

4. Zero Harmonic Output

The output waveform is a standard sine wave, with a waveform distortion rate of < 0.1%, and does not generate any additional harmonics. Compared with traditional electronic voltage stabilizers, it does not inject high-frequency interference into the power grid, and is particularly suitable for medical, precision testing, and communication places with strict electromagnetic environment requirements.

5. Redundant Dual-Bypass Protection

Integrated with manual/automatic dual bypass functions. When there is an internal fault in the voltage stabilizer or during regular maintenance, it can seamlessly switch to the direct power supply mode through the bypass switch to ensure that the load never loses power. After the maintenance is completed, 3 Phase 50KVA Servo Motor AVR can be switched back to the voltage stabilizing mode, with the entire process requiring no shutdown.

6. Large Capacity Heat Dissipation and Ultra-long Life Design

For the 50KVA level heat generation, large-sized heat sinks and intelligent temperature-controlled speed-regulating fans are adopted to ensure that the full-load temperature rise is < 60℃. Selecting A-grade high insulation level materials and imported wear-resistant carbon brushes, the overall design life exceeds 15 years, and the comprehensive cost throughout the entire life cycle is much lower than similar electronic voltage stabilizers.

7. Deep Integration of Communication

Standard configuration includes RS485 communication interface (Modbus-RTU protocol), and optional Profibus-DP or Ethernet communication modules. It can be used to read three-phase voltage, current, temperature, and alarm status in the control room in real time, enabling unmanned operation and predictive maintenance.

Product Applications

1. Precision Manufacturing and High-End Equipment: Provide zero-harmonic and highly stable pure power supplies for semiconductor packaging and testing lines, SMT soldering machines, and CNC equipment groups of precision mold processing centers, thereby improving the yield rate.

2. Power Supply for Large Medical Facilities: Used for the front-end voltage stabilization and harmonic isolation of large medical imaging equipment such as CT machines, MRI (magnetic resonance) systems, and linear accelerators in the radiology and nuclear medicine departments of tertiary hospitals, ensuring imaging quality and equipment safety.

3. Data Centers and Edge Computing Nodes: Provide voltage stabilization and harmonic control for the switch power supplies and precision air conditioning systems of small and medium-sized data rooms and 5G core convergence data rooms, reducing UPS input harmonic losses and extending battery life.

4. Vehicle Manufacturing and Automotive Parts Production Lines: Provide control cabinets and servo drive systems for welding robot workstations, painting robots, and large stamping lines to ensure multi-axis linkage accuracy and avoid welding splashes or painting defects caused by voltage fluctuations.

5. Large Commercial Complexes: Installed in shopping malls, five-star hotels, and large exhibition halls, the main power distribution rooms provide centralized power quality optimization for the power and lighting, escalators, and central air conditioning units of the entire floor or entire building.

6. Chemical and Pharmaceutical Industries: Provide voltage stabilization protection for reaction vessel stirring motors, centrifuges, and air compressor groups, and also suppress the harmonics generated by motor frequency converters from interfering with DCS control systems and on-site instruments.

Support customization

KTAC offers 3 Phase 50KVA Servo Motor AVR OEM/ODM services, including appearance color, packaging method, input/output voltage range, and special function modules (such as EMI filter devices, lightning protection devices, RS232/RS485 monitoring interfaces), etc. Please contact us for customized solutions.

FAQ

1. Can the 50KVA voltage stabilizer really achieve the "harmonic isolation" effect?

Yes. The SBW-50KVA operates based on the principle of a compensation transformer, with electromagnetic isolation between the input and output. It has a natural attenuation effect on high-frequency harmonics (especially those above the 5th harmonic) (typically capable of attenuating 30% to 50%). At the same time, it does not generate switching frequency harmonics (unlike PWM-type electronic devices), which can significantly reduce the reverse pollution of harmonics from the load side to the power grid. If more thorough harmonic control is needed, we can add an active filter (APF) or passive filter branch in advance.

2. What are the requirements for the front-end circuit breaker when this device is connected to the power distribution system?

The rated current of the 50KVA model is approximately 76A (three-phase 380V). Considering the starting surge of motor-type loads and a certain capacity margin, it is recommended to configure a plastic-case circuit breaker (MCCB) with a rating of 100A to 125A at the front end, and select a C/D type trip curve. The incoming cable is recommended to use YJV 3×25mm² + 2×16mm² or higher specifications, and the specific requirements need to be calculated based on the actual line length for voltage drop.

3. Can the three-phase independent regulation solve the problem of excessive total neutral current caused by unbalanced load?

It can solve the problem of voltage imbalance, but the three-phase independent regulation adjusts the voltage of each phase rather than forcibly distributing the current of each phase. If the three-phase current on the load side is severely unbalanced (for example, the difference exceeds 50A), the voltage stabilizer can ensure the symmetry of three-phase voltages, but it cannot reduce the neutral current. In this case, it is recommended to evenly distribute the single-phase load at the power distribution terminal, and we can provide consultation on the load balance distribution plan.

4. Does the 3 Phase 50KVA Servo Motor AVR have protection functions in bypass mode?

In the manual bypass mode, the overload and overvoltage electronic protection functions of the voltage stabilizer do not participate. At this time, the rear-end equipment is powered directly by the mains, losing the voltage stabilizing protection but maintaining continuity. It is recommended that users arrange maintenance as soon as possible during bypass operation. During automatic bypass (fault switching), the equipment will still monitor the mains status. If the mains are severely abnormal and exceed the safety threshold, some protection signals can still trigger the front-end circuit breaker for alarm.

5. What are the special features of the cooling solution for the 50KVA model?

The power loss and heat generation of the 50KVA model (approximately 2KW) are significantly higher than those of small-power models. We adopt an enhanced cooling solution of "copper tube radiator + intelligent double ball bearing fan", with the fan speed automatically adjusted without step change according to the internal temperature. Under a full-load 40℃ environment, the internal temperature rise is strictly controlled within 60℃. It is recommended to ensure that there is a ≥30cm gap for heat dissipation and ventilation on the front, back, left and right sides of the equipment during installation.

6. Will the dust from the carbon brush affect other electrical components in the power distribution cabinet?

The carbon brush will produce trace amounts of graphite dust during long-term sliding operation. We have set up a dedicated dust collection trough and detachable dust filter screen inside the cabinet. Most of the dust is collected at the bottom of the machine and will not escape into the power distribution cabinet. It is recommended to use a vacuum cleaner to clean the bottom dust collection port once every six months, which is very convenient to operate.