Product Description
The variable frequency series resonant test device is mainly
designed for AC withstand voltage tests of cross-linked cables,
hydro generators, main transformers, busbars, GIS, etc. It has a
wide range of applications and is an ideal withstand voltage
testing device for high voltage testing departments at the
regional, city, and county levels, as well as for power
installation, repair, and testing units.
The variable frequency series resonant test device is primarily
composed of a variable frequency control power supply, excitation
transformer, reactor, capacitive divider, and optional compensation
capacitor.

Suitable for the commissioning and preventive testing of large
capacity, high voltage capacitive test samples. The device features
over-voltage, over-current, zero start, and system detuning
(flash-over) protection functions. The entire device is
lightweight, making it convenient for on-site use.

Product Features
- 1. Significantly Reduced Power Supply Capacity. Series resonant power
sources use resonant reactors and the test sample's capacitance to
generate high voltage and high current. In the entire system, the
power supply only needs to provide the active power consumption, so
the required power supply capacity is only 1/Q of the test
capacity.
- 2. Greatly Reduced Weight and Volume. The series resonant power
source eliminates the need for bulky high-power voltage regulators
and ordinary high-power power frequency test transformers. The
resonant excitation power supply only needs 1/Q of the test
capacity, significantly reducing the system's weight and volume,
typically to 1/10 to 1/30 of conventional test devices. Improved
Output Voltage Waveform. The resonant power source acts as a
resonant filter circuit, improving the output voltage waveform
distortion, achieving a good sine wave, and effectively preventing
harmonic peak values from causing false breakdowns of the test
sample.
- 3. Prevention of Large Short-Circuit Currents. In a series resonant
state, if the test sample's insulation weak point is broken down,
the circuit immediately detunes, and the loop current quickly drops
to 1/Q of the normal test current. In contrast, with parallel
resonance or test transformer methods, the breakdown current
immediately increases dozens of times, resulting in short-circuit
and breakdown currents differing by hundreds of times. Therefore,
series resonance effectively identifies insulation weak points
without the risk of large short-circuit currents damaging the fault
point.
- 4. No Recovery Over-voltage. When the test sample breaks down, the
high voltage immediately disappears due to the loss of resonance,
the arc extinguishes instantly, and the reestablishment process of
the recovery voltage is very long, making it easy to disconnect the
power before reaching flash-over voltage again. This recovery
process is a kind of energy accumulation intermittent oscillation
process, which is long and does not generate any recovery
over-voltage.
Product Parameters
- 1. Rated output voltage: based on different test objects, max up to
1000kV.
- 2. Output frequency: 20- 300Hz.
- 3. Waveform: pure sine wave, THD <1.0%.
- 4. Max. capacity: Max up to 20000kVA
- 5. Duty Cycle: Continuous working time 60 mins at full power output.
- 6. Frequency adjustment sensitivity: 0.1Hz, instability <0.05%.
- 7. Power Supply: 380/220V ± 15%/50Hz ± 5%.
- 8. can customzied partial discharge resonant test system
FAQ
- 1.Is your company a sales company or a manufacturer? Sansion Power Electric Co., Ltd. is an industrial and trade
enterprise with its own factory, self-produced and self-sold.
Founded in 2005, we have twenty years of production experience with
reliable production lines, test rooms, and R&D centers.
- 2.Are goods in stock, can they be customized, and what is the
delivery time? Goods are made to order according to customer requirements using
the latest technology. Delivery time is typically within 10 working
days.
- 3.Is the quality guaranteed? We use imported components and conduct three quality inspections
before shipment. Export products are packed in non-fumigation
wooden boxes.
- 4.What are the after-sales terms? We offer free consulting service, one year warranty, and support
through email communication, video calls, and on-site technical
assistance to resolve after-sales problems promptly.
- 5.What are the cooperative countries or regions? Products exported to United States, France, Brazil, Australia,
Spain, Portugal, Oman, Russia, Netherlands, Indonesia, Bangladesh,
Saudi Arabia, Chile, Colombia, Panama, Malaysia and other
countries.
About Sansion
Established in 2005, Sansion Power Electric comprises technical
experts with over 20 years of experience in R&D, manufacturing,
and marketing of power electrical testing products. Our solutions
are widely applied across power electric, railroad, energy
conservation and environment protection, water conservancy,
petrochemical industry, aerospace, and other sectors.
Sansion Power Electric includes R&D department, instruments
manufacturing workshop, HV workshop, sample exhibition room, HV
testing laboratory, quality control department, general office,
sales departments, and information office. We currently employ over
80 staff members, including 20 technical engineers.
We have obtained ISO9001 quality system certification, and all
products strictly conform to international IEC and Chinese state
standards.



