CAT Genset Voltage Regulation

[KBasson]

Good Day All

I would really appreciate guidance or assistance with respect to the following issue. We have numerous mobile operating gensets in operation at various remote locations in Africa. On numerous occasions, the voltage regulators has failed. I would like to know if there is any possibility that idling the machine at below operating speed could have an effect on the VR performance. The typical size range of the gensets range from about 500kVA to 1500kVA with an output voltage of 380V. Any suggstions in this regard will be helpfull.

Thank You

 

[danielmurray]

Yes it could. Many VR's have adjustments for limiting excitation to a level suitable to the application. A resistor is sometimes used in series with the field to limit current. We use speed switches on some applications to turn the VR off below a set RPM. The bottom line is that the VR should be correctly sized and suited for the application. It should then be correctly installed and adjusted.

 

[jbartos]

Suggestions:
1. During idling the VR has to regulate relatively high generator output voltage to the VR set voltage, i.e. to the generator nominal voltage.
2. Voltage regulators should also fit the environmental conditions, e.g. ambient temperature, humidity, dust particles count, EMI, etc.