Single Phase Servo Voltage Stabilizer

The AC voltage stabilizer has been in Chinese market for over 20 years. The main circuit structure of the product develops over years from the originally mechanical carbon brush type to the current contactless compensation type. As a high-tech company in Shanghai, Pandeng is a professional power supply protector manufacturer. Since 1990 when we established, we have become a leading company with remarkable achievements and good reputation in this industry.

The common AC voltage stabilizer on sale is the three phase electrical voltage regulator. Advantages as it has, it has such disadvantages as short service life, low reliability and long response time because it regulates voltage by mechanical transmission and carbon brush. It is therefore gradually replaced by the contactless compensation voltage stabilizer, which also has some disadvantages, for example, it has stepped regulation only and low voltage stabilizing precision (usually 3%). Due to the low voltage stabilizing precision, a large number of compensators are needed, so a large number of circuit changers are needed in the full-bridge switching circuit.

SGW5C contactless induction voltage regulator combines the advantages of the above two products and discard the disadvantages. The product is manufactured according to the ministerial standard YD/T 1325-2004 and all the technical indexes reach or exceed the standard. The main part of the product is induction voltage regulator. It is a contactless regulator, so it has no contact device or wear part (e.g. carbon brush), no noise and no surge caused by brush contact spark. Besides, it has strong transient overload capacity, high safety and low mechanical failure, so it is maintenance-free for a long time. Based on the electromagnetic induction principle, it can support stepless linear regulation of output voltage. There's no unstable voltage, or wave distortion in the working process, and there is no current surges during tap changing operation, either. The product is small in size, firm and durable, and has strong overload capacity, low mechanical failure and easy maintenance.

Schematic Diagram

SGW5C consists of induction voltage regulator, control circuit, output sampling circuit, output control circuit, control circuit, bypass circuit, etc.

Working Process
When the input voltage or the electrical load fluctuates, the output sampling circuit will make response and compare the input voltage with the reference voltage. The control circuit will then send a signal to control the induction regulator so as to achieve a stable output voltage. Meanwhile, the control circuit controls the protection circuit and output control circuit simultaneously.

The main part of the product is the induction voltage regulator, which regulates the induced voltage of the stator winding according to relative displacement between the stator and the rotor. The main components of the induction voltage regulator are the rotor (R) and the stator (S) (See the picture below). The rotor winding which in parallel connection with the power system is the primary winding, while the stator winding which in series connection with the power system is the secondary winding. When voltage E1 is input between 3 and 4 (rotor winding), the voltage E2 between 1 and 2 (stator winding) is determined by the angle Θ between the rotor winding and the stator winding (E2=E1*COSΘ), i.e. the output voltage changes with the relative displacement between the rotor winding and the stator winding.


Design Characteristics
1. Stepless and linear voltage regulation
Based on the induction principle, SGW5C can make stepless and linear regulation of the output voltage. It comes with no noise, no contact spark and no surge. The voltage output is identical with the input voltage. However, for the carbon brush voltage regulator, spark, electric arc and surge are produced with the touch on the coil surface by the brush. Transient surge will cause system failure of the regulator.
2. Firm and durable, long service life
Since the main part of the product is the induction voltage regulator, it has no contact or wear. It consists of the outer case, the windings and the silicon steel sheets, which are firm and durable to surge or nonlinear electrical loads. Its design service life is over 15 years. However, for the carbon brush voltage regulator, brush wear is caused by the touch on the coil surface with the brush.
3. Strong overload capacity
Different from voltage regulators of other types which adopt carbon brushes or semiconductor modules to conduct current, the product adopts windings which have a strong overload capacity. System failure caused by transient overload is avoided.
4. Easy maintenance
Due to the modularized design inside, all the components are standardized. The product is maintenance-free and needs only external cleaning while for the carbon brush voltage regulator, regular maintenance and brush renewal are needed due to the brush wear. Besides, the coil surface should also be regularly polished.
5. Small in size and light in weight
Designed with patent structures and manufacturing technology, combined with precise mechanical assembly, SGW5C has a small size, light weight and a great capacity.
6. Resistant to environmental extremes
The product is made up of high-quality components, so even used under extreme temperature and moisture, intensive shock or dirty environments, its service life will not be reduced. However, for Carbon brush voltage regulator, the carbon brush is fragile during transportation or used under intensive shock due to the poor shock resistance. Besides, with the coils exposed, short circuits are easy to occur in environments filled with oil gas, steam or smoke.
7. Good surge protection
Transient surge is produced when large scale equipment start or stop. Our product is equipped with a surge protector to ensure the regular work of the backend equipment.
8. Wide range of input voltage
The product can endure a wide range of input voltage and even work with unstable power supply. All the components are particularly selected to resist instantaneous overvoltage and overcurrent.
9. Careful material selection
The materials selected are low iron-loss silicon steel sheets with high magnetic conductance. The sheets are punched and annealed to ensure the stability of the material attributes. It adopts the F-class insulation material -- anaerobic enameled copper wire to minimize the copper loss.

Product Applications
Besides its small size and light weight, SGW5C also has the advantages of easy installation and use, reliable function, uninterruptable operation and transient surge resistance. It is applicable for large scale electromechanical equipment, metal processing machines, production line, constructional engineering equipment, medical instruments, textile machinery, air conditioners, broadcast and television equipment and illumination in the fields of industry, agriculture, traffic, communication, military, railway, scientific research, etc. It is especially adaptable to frequent-started inductive loads because when started, it can endure 8 times of the current.

The product is particularly applicable for the equipment as follows: CNC automatic punching machines, CNC automatic bending machines, CNC mould engraving machines, metal laser cutting machines, automatic PCB boring machines, CNC machine centers, SMT panasert machines, precise circuit etchers, exposure machines, laser plotters, precision color printers, precision wire cutting machines, specular electric discharge machines, medical equipment and chemical engineering equipment.

The following items should be informed when ordering.
1. Confirm the rated output voltage according to working voltage of the loads.
2. Confirm the input voltage range according to the voltage fluctuation.
3. Confirm the rated capacity according to the power capacity, power factor and attributes of the loads. The inductive load power factor is 0.75, without consideration of the start-up current influence. The capacity is twice the load current in terms of nonlinear loads (e.g. frequency conversion equipment and UPS).
4. Specifications can be designed according to customers' requirements.

Technical Parameters
Input voltage For three phase stabilizer, 323~437V (±15% compensation range), 304~456V (±20% compensation range), 266~494V (±30% compensation range), ±40% and ±50% compensation range available
Frequency 50/60 Hz
Rated capacity For three phase stabilizer, 20KVA~3000 KVA
Output voltage For three phase stabilizer, 380V, tracking adjustment
Voltage stabilizing precision ± 1~5%, adjustable (default setting ±2 %)
Response time ≤ 200 ms, ±10% variation between input voltage and rated value
Output waveform No wave distortion or harmonic increment
Efficiency ≥ 97%
Temperature rise Transformer winding < 105oC
Noise ≤ 50 dB
Winding insulation class F
Insulation resistance Input and output earth ground insulation resistance ≥ 2MΩ
Insulating strength Input and output earth ground AC voltage 2000V/1min, no flashover or spark-over
Main Functions
Power on mode Voltage regulator is provided with automatic power on and manual power on for users to choose.
Short circuit protection When the regulator has short circuit problem in the output end, the circuit breaker will automatically cut off the power input.
Over and under voltage protection When output voltage exceeds about ±10% than rated value, the regulator will automatically cut off the output and send out sound alarm.
Manual bypass The regulator can be manually transformed to work in bypass circuit.
Alarm and silencing function The regulator has alarm and silencing switches for selection.
Lightning surge protection It is equipped with 40kA surge protector. Regulators of larger capacity or imported surge protectors can also be selected.
Remote monitoring (optional) The regulator can be equipped with remote monitoring system in order to monitor its operation.

The model and illustration of SGW5C contactless induction voltage regulator is as follows

Model Specifications
Model Rated capacity (KVA) Rated current(A) Allowable fluctuation
range of input voltage (V)
Output voltage (V) Size
(Height*width*thickness mm)
Weight (Kg)
SGW5C-20 20 30 323~437
(±15% compensation range)
(±20% compensation range)
(±30% compensation range)
380V ±1~5%, adjustable 800*400*480 70
SGW5C -30 30 45 80
SGW5C -40 40 60 90
SGW5C -50 50 75 870*480*560 130
SGW5C -70 70 105 150
SGW5C -100 100 152 950*560*620 200
SGW5C -120 120 182 220
SGW5C -150 150 228 1050*600*700 300
SGW5C -200 200 304 330
SGW5C -250 250 380 1500*700*800 480
SGW5C -300 300 456 530
SGW5C -400 400 605 570
SGW5C -500 500 760 2000*1000*900 1060
SGW5C -600 600 912 1170
SGW5C -800 800 1216 1280
SGW5C -1000 1000 1520 2200*1400*1000 1570
SGW5C -1250 1250 1900 1810
SGW5C -1500 1500 2280 2010
SGW5C -1750 1750 2660 2340
SGW5C -2000 2000 3040 2200*1600*1500 3400
SGW5C -2500 2500 3800 3930
SGW5C -3000 3000 4560 4480

Note: Size in the chart is for ±15% compensation range type.

User Instructions
1. SGW5C contactless induction voltage regulator should be connected with the null line.
2. Terminal S1: When there is over or under voltage, if the system is not connected by short circuit (default setting), the regulator will automatically cut off the output and send out sound alarm; if it is connected by short circuit, the regulator will send out sound alarm only.
Terminal S2 : When the main air break is on, if the system is connected by short circuit, the regulator starts automatically; if it is not connected by short circuit (default setting), the regulator starts by pressing the start button.
3. If the main air break of the voltage regulator automatically trips, the system is over loaded or short circuited. The main air break can be restart only when the fault is cleared.
4. If the voltage regulator emits smell or smoke, the power should be cut off immediately and professional maintenance is in need.
5. If the voltage regulator is in bypass state, all protection functions will not work. Users should check the input voltage in case of load failure.
6. Manual bypass switch QN should not be operated with power on.
7. The regulator should be powered off and the main air break should be cut off after a whole day's work.
8. The regulator is at least one meter away from the back wall for the sake of maintenance.

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Main Products
  • SBW5T Adjustable Regulated Power Supply Our adjustable regulated power supply can fully meet the demand for regulating output voltage value within a large scope, offering stable alternating voltage in compliance with definite value for the inspected product.
  • Three Phase Energy Saving Cabinet With the housing made of cold rolled steel sheet with the thickness of 2mm, the three phase energy saving cabinet has a high compressive strength and is thus able to protect the electronic voltage regulator and other components inside of it.