VLF hipot test set

High voltage withstand testof electrical equipment is one of the most important items specified

ininsulation preventive test.

The withstand voltage testcan be divided into ac withstand voltage test and dc withstand voltage

ultra-lowfrequency technology is the latest technology recommended by the current  international

electrotechnical commission. Our company's new generation of

ultra-low frequency and high voltage generator is the core productindependently developed with the latest American technology. It adopts 7-inchtouch screen, the latest arm7 single chip microcomputer,

highspeed adacquisition circuit, and is equipped with background management software. Itovercomes

many shortcomings of domestic similar products (see table 1), and itscost performance is much higher

than that of similar imported products. It isespecially suitable for withstand voltage test of electrical

equipment with large insulation equivalent capacitance (such as power cable, power capacitor,large and

mediumsized generator and motor, etc.), which conforms to thenational standard of electric power

industry, general technical conditionsforultra-low frequency and high voltage generator(d) newly  issued in 2004 l /t849.4-2004.

Table 1 performance comparison betweenmechanical type and electronic type of 0.1Hz voltage  withstand test equipment

In fact, the ultra-low frequency insulation withstand voltage test is an alternative to the powerfrequency

withstand voltage test. In the power frequency withstand voltage testof large and medium-sized generators, motors, power cables and other test objects,due to their large capacitance in the

insulation layer, a large capacity testtransformer or resonance transformer is required. Some of these

huge equipmentis not only heavy and expensive, but also inconvenient to use. In order tosolve this

contradiction, the method of reducing the test frequency and thecapacity of the test power supply is

widely used in the world. It has beenproved from many years of theory and practice at home and abroad that replacingpower frequency withstand voltage test with 0.1Hz ultra-low frequency withstandvoltage test can not only have the same equivalence, but also greatly reduce the volume and weight of the equipment, theoretically, the capacity is aboutone fifth of the power  frequency, and the operation is simple. This is the mainreason why this method is widely used in  developed countries.

According to the actualsituation of China's power system, the national development and Reform Commission has formulated the industry standard of ultra-low frequency (0.1Hz)withstand voltage test method for 35kV and below XLPE insulated power cables. In 2004, the industry standard DL / T 849.4-2004, general technical conditionsfor ultra-low frequency and high voltage generators, which is being promoted inChina. Although the DC voltage  withstand test equipment has the advantages ofsmall size, light weight and low cost, the DC voltage withstand test is alsothe most destructive to the insulation of the tested object. (see Table 2)therefore, the  latest national regulations on preventive test of electricalequipment have expressly stipulated that DC  high voltage is no longer used forvoltage withstand test of electrical equipment, and AC voltage  withstand testis recommended.

The new generation of 0.1Hzultra-low frequency high voltage generator developed by our company adopts thelatest power electronic

components and the latest ARM7 single-chip technology,further reducing the volume and weight of the equipment, fool operation, morestable

performance, overcoming the shortcomings of the first generation ofmechanical booster, such as short

service life, high failure rate and largevolume. Through years of practice, a large number of user feedback shows that:- 80kV ultra low  frequency  high  voltage  technology  is  leading  in  the  country, with  the  highest cost performance!

Table 2performance comparison of various withstand voltage test equipment:

III.  technicalparameters of seriesproducts

Ground voltage generator