1. DC Voltage Test System
Applications
The cascaded DC high voltage generator is mainly used to inspect and test the performance of the
insulation materials under the action of DC voltage, the DC discharge performance of the air gap, to
conduct the insulation performance test for the large capacity test products (power
cables, power capacitors and generator sets) and to measure the leak current in high-voltage electrical
products made of insulation materials, and used also to conduct DC pollution test for extra-high-voltage
DC power transmission equipment.
Feature
If the test object is a nearly pure capacitive load, e. g. an extruded cable sample, the test system has to
supply only the charging current of up to several milli-Amps. Few 10 mA are necessary for withstand
testing of dry, high-resistive indoor insulations as insulators, bushings, switchgear, etc. For both
applications IEC 60 060-1 defines the quality of the HVDC test voltage by its ripple factor (half the
difference between maximum and minimum voltage related to its arithmetic mean), which should not
exceed 3 %.
If the test object has a lower resistance, e. g. in case of outdoor insulation, where the leakage current
cannot be neglected a higher test current in the order of few 100 milli-Amps is necessary. In addition to
the ripple, the voltage drop caused by the non-disruptive currents from predis-charges must be limited
to less than 10 % (IEC 60 060-1).
For pollution testing HVDC test systems must be able to fulfill the above requirements for ripple factor
and voltage drop. This is only possible if the systems is able to supply currents in the order of 1000
milli-Amps and a feedback control of the output DC voltage to the input HVAC voltage of the generator is
applied. HIGHVOLT applies for such test systems a special design based on the requirement of the
customer.
Our Product characteristic is: Reasonable in structure, 士200Kv一士12OOkV in rated voltage, stable in
output current, small in voltage drop and low in pulsation coefficient; A silicon-controlled automatic
tracking voltage regulation measure is adopted, through the test product current and the voltage signal
feedback, to realize dynamic voltage regulation, thus ensuring that the voltage applied to the test product
should be stable .The requirement for the voltage drop to be within 5% and the voltage overshooting to
be less than 8% within a duration of 0.5 second and under a 500 MA resistive load current on the test
product can be satisfied.
2. In summary:
1. Low in pulsation coefficient
2. High in measurement accuracy, stable in output voltage and strong in anti- interference capacity.
3. With the test completed or the test product changed, the main body will get the main capacitor
short-circuited and grounded automatically for discharge, thus making it excellent in safety performance.
4. Through the test product current and the voltage signal feedback to realize dynamic voltage regulation,
thus ensuring that the voltage should be stable .
For further information please contact:
Power Electric Co ., Ltd
Add: No.9 longchuan North Road, Jiangdu,Yangzhou City, Jiangsu province,China
Tel: :+86-514-86688088
Fax: 86- 514-86688588
E-mail: sales@powerhv.com
Http:// www.powerhv.com
