High Voltage Booster
Darui Electric recommends:
The test high voltage transformer is produced based on the Ministry of Machinery and Electronics' "Test Transformer" standard, after extensive improvements on the basis of similar products. The AC/DC high voltage test transformer is a new type of product produced after improvements on the basis of the YD series test transformer, in accordance with the national standard "JB∕T 9641-1999".
Capacity Selection of Test Transformer
The formula for determining the nominal capacity Pn of the test transformer: Pn=KVn2ωCt×10-9.
Where: Pn----nominal capacity of the test transformer (KVA).
Vn-----the effective value of the rated output high voltage of the test transformer (KV).
K-------safety factor. K≥1, when the nominal voltage Vn≥1MV, K=2, when the nominal voltage is lower, the K value can be taken higher.
Ct------capacitance of the test object (PF).
ω----angular frequency, ω=2πf, f-----frequency of the test power supply.
The capacitance Ct of the test object can be measured by an AC bridge. Ct varies greatly and can be determined by the type of equipment. Typical data are as follows:
Simple bridge or suspension insulators: tens of microfarads.
Power transformers: < 1000KVA - 1000PF > 1000KVA 1000 – 10000PF.
High voltage power cables and oil-impregnated paper insulation: 250 – 300PF/m.
Enclosed substations, SF6 gas insulation: 100 – 10000PF.
For different test voltages Vn, choose different (appropriate) safety factors K. The K values selected for different Vn are listed above for reference:
Vn = 50 – 100KV K=4 Vn = 150 – 300KV K=3 Vn > 300KV K=2.
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
