YDQ Inflatable Test Transformer Product Introduction
Darui Electric recommends
The inflatable AC test transformer is essential testing equipment for power equipment detection and preventive tests. With the development of China's power industry, the voltage level requirements for test transformers are increasingly higher, while traditional oil-immersed test transformers, whether in terms of volume, weight, or performance, are increasingly unable to meet on-site work requirements.
With the advancement of basic scientific research in China, the application of new materials and new processes has introduced the new medium sulfur hexafluoride gas into the application field of power equipment. Due to the excellent insulation performance, arc extinguishing performance, and non-flammability of sulfur hexafluoride gas, it has been widely used as a new insulating medium.
After years of efforts, our company has successfully developed the inflatable AC test transformer. Compared with traditional oil-immersed light test transformers, this series of products reduces weight by 20%-60% (depending on voltage and capacity levels), and has no oil pollution. The voltage level of a single inflatable AC test transformer can reach 300KV. Due to the adoption of new production processes, the technical performance of the products has been significantly improved, especially suitable for on-site work and frequent mobile working conditions.
Product Aliases
YDQ AC/DC SF6 Gas Test Transformer, Inflatable Test Transformer, High Voltage Withstand Test Device, Power High Voltage Test Transformer, Ultra-Light High Voltage Test Transformer, High Voltage Test Transformer, Power Frequency Withstand Test Device, Inflatable Test Transformer, SF6 Gas High Voltage Withstand Tester, Gas Test Transformer
YDQ Inflatable Test Transformer Product Features
1. This product is small in size and light in weight (40%-65% lighter than oil-immersed test transformers of the same level)
2. Clean, no oil contamination, no maintenance required;
3. Unaffected by harsh climate conditions, can be tested immediately after on-site handling without needing to rest;
4. Insulation strength is significantly higher than oil-immersed test transformers, with minimal corona;
Product Parameters
1. Voltage level: 10kV～600kV
2. Capacity range: 1～500KVA
3. No-load current: ＜7%
4. Impedance voltage: ＜8%
5. Product types: AC, AC/DC, AC series, AC/DC series
Selection of test transformer:
The rated voltage on the high-voltage side should not be less than the maximum test voltage of the test object, and the rated current should not be less than the maximum capacitive current of the test object.
The calculation formula for the capacitive current of the test object and the required capacity of the test transformer is:
I = 2π f Cx U × 10 -6
U I = 2π f Cx U 2 × 10 -9
Where I — capacitive current of the test object, A; f — power frequency, Hz;
Cx — capacitance of the test object, μF; U — effective value of test voltage, V;
Se — required rated capacity of the test transformer, KVA
The capacitance Cx of the test object can be measured by an AC bridge. The common capacitance of test objects is selected according to the table below.
Usage of Inflatable Test Transformer:
The YDQ sulfur hexafluoride (SF6) inflatable test transformer is designed and produced based on the oil-immersed test transformer according to the "Test Transformer" standard. SF6 gas has good electrical insulation performance and excellent arc extinguishing performance. Its withstand voltage strength is 2.5 times that of nitrogen at the same pressure, and its breakdown voltage is 2.5 times that of air. At 0.25MPa, it is equal to the breakdown voltage of oil, and at 0.45MPa, it is twice the breakdown voltage of oil. It is a new generation of ultra-high voltage insulating medium material superior to oil. The technical requirements of this product fully comply with the "ZBK-41006-89" standard. It is a replacement product for oil-immersed light test transformers. This product has the characteristics of small size, light weight, unaffected by climate changes, low corona, no need to rest after on-site handling, long service life, and maintenance-free. It is suitable for insulation strength tests under power frequency or DC high voltage for various high-voltage electrical equipment, electrical components, and insulating materials in power systems, industrial and mining enterprises, and scientific research departments.
II. Usage of Inflatable Test Transformer
1. Connect the working circuit and ground it properly.
2. Set the voltage and current setting values according to the manual.
3. Raise the voltage according to the regulations, and the voltage increase speed must be less than 3000V/s.
4. When the voltage rises to the test voltage, start timing. After 1 minute, quickly reduce the voltage to below 1/3 of the test voltage before cutting off the power.
5. During the voltage increase or withstand test, if any of the following abnormal conditions are found, immediately reduce the voltage, cut off the power, stop the test, and find out the cause.
(1) The voltmeter pointer swings (or the digital reading jumps) significantly
(2) The ammeter reading rises linearly
(3) Abnormal sounds inside the test object
6. Item 9 is the pressure valve and pressure gauge, which are in a long-term closed state. Open the valve once every 6 months to check the SF6 pressure, which should not be less than 0.4MPa (close the valve immediately after checking the pressure). If it is lower than 0.4MPa, add SF6 gas to increase gas insulation.
7. Before and after the withstand test, the insulation resistance of the test equipment should be measured to check the insulation condition.
8. Operation must strictly comply with relevant national standards and operating procedures, referring to GB311-83 "Insulation Coordination of High Voltage Transmission and Transformation Equipment, High Voltage Test Techniques", "Preventive Test Regulations for Electrical Equipment", etc.
III. Supporting Products for Inflatable Test Transformer
1. Operating System
Operating box: Capacity: 1～5kVA, Input voltage: 0.22kV
Operating console: Capacity: 10～300kVA, Input voltage: 0.22, 0.38kV
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
