Impulse Voltage Generator (Electromagnetic)

 

Application

GTU type Impulse generators are suited for use in research and industrial test laboratories. They are made according to a modular principle for voltages from 100kV to 2000kV, with stored energy values ranging from 5kJ to 100kJ. For lower voltages, we supply high voltage construction kit, and for higher voltages GTN type generators are supplied.

Function

For the production of impulse voltages, a number of parallel-connected impulse capacitors is charged by means of the charging resistors. After the capacitors are charged to the desired energy, they are connected in series by means of spark gaps, and then discharged. The shape of the impulse wave to be produced can be altered by suitably dimensioned front and tail resistors. Normally, 1.2/50-µs impulse waves are used for the testing of high voltage apparatus as per IEC60060-1.

Design

The impulse generator mainly comprises of DC charging unit, charging resistors, impulse capacitors, spark gaps, discharge resistors and a control desk.

The DC charging unit produces DC voltage and applied to the individual impulse capacitors via a protective resistor and the corresponding charging resistors. The impulse capacitors are arranged stage-wise one above the other. The capacitors are installed in sheet-steel tanks. They are insulated for 100kV, one end is grounded, the other end is insulated.

The spark gaps are arranged in horizontal position and fixed to FRP-tubes. The spark gaps have semi-spheres of copper, with a trigger electrode on one of the semi-spheres. The gap setting can be changed from the control desk for triggering the impulse generators.

The wave shaping resistors are designed for Anti-inductive, made of Nickel-chromium alloy and provided plug-in terminals for easy connection. They can be exchanged to allow for different front times and times-to-half value of the impulse voltage.

 

Advantages of GTU Type Impulse Generators

  • Efficiency for Lightning impulse: >90%
  • Efficiency for Switching Impulse: >80%
  • Minimum Charging Voltage: ~10%
  • Discharge resistors easy to exchange for the generation of lightning or switching impulses
  • Compact design.

 

GTU Generators Images