After generating ZnO surge arrester using Zno Data Function we obtain a punch card which we can use for any surge arrester from a particular model and manufacturer for any rated voltage.
What value of Vref do we need to enter in order to scale the data?
For example - I produced a 96kV rated surge arrester .pun card - then wanted to convert it to a 120kV rated equivalent. The Zno Data Functionrecommends we use 2 x Vrated when generating the data - ie 192kV. In the ZnO model for the 120kV rated equivalent should I make Vref = 240kV ?
Why can't I make Vref = Vrated to simplify things?
Any help would be appreciated.
ZnO Arrester Models
For numerical stability purposes only, the program suggests that you use 2 x V rated. But other values function also in most cases
To convert an already functionnal arrester model, you only need to multiply the Vref value by a proportion. For your exampe this proportion in your case is 120/96.
Someone could help me
Someone could help me to modelling ZnO surge arrester?
Details are as follows:
- SIEMENS
- Duty cycle voltage: 96 kV
- MCOV: 76 kV
- TOV capability: 109 kV (for 1 s) and 102 kV (for 10 s)
- Protective level (Maximum discharge voltage):
* FOW 10 kA:259 kV
* for 8/20 us (impulse):
- at 1.5 kA: 202 kV
- at 3.0 kA: 214 kV
- at 5.0 kA: 221 kV
- at 10.0 kA: 235 kV
- at 15.0 kA: 252 kV
- at 20.0 kA: 263 kV
- at 40.0 kA: 294 kV
* for 45/90 us (impulse):
- at 500 A: 188 kV
- at 1.0 kA: 195 kV
- at 2.0 kA: 204 kV
Appreciate your help,
Saulo Hernandez