powerzizo
Mechanical
- Aug 23, 2013
- 15
Hi All,
we have four similar 360MW steam turbine generating units build in 2002, The generating units are equipped with static excitation system. The generator output voltage is controlled through automatic voltage regulator. The voltage regulator controls the output of 18 thyristors rectifiers’. The resulting controlled DC power is supplied to the generator field winding to get controlled voltage at generator terminals.
during the last two months, we experienced three incidents in the same unit where everytime we receive excitation system light fault alarm in DCS and we find one thyristor stack fuse blown and capacitor exploded and its fluid spilled out, then we shutdown to replace the defective thyristor stack and run the unit again. we are in discussion with the OEM but root cause has not been concluded.
your thoughts are appreciated , if someone experienced similar incidents. noting that the other three units with the same age never had similar incidents.
we have four similar 360MW steam turbine generating units build in 2002, The generating units are equipped with static excitation system. The generator output voltage is controlled through automatic voltage regulator. The voltage regulator controls the output of 18 thyristors rectifiers’. The resulting controlled DC power is supplied to the generator field winding to get controlled voltage at generator terminals.
during the last two months, we experienced three incidents in the same unit where everytime we receive excitation system light fault alarm in DCS and we find one thyristor stack fuse blown and capacitor exploded and its fluid spilled out, then we shutdown to replace the defective thyristor stack and run the unit again. we are in discussion with the OEM but root cause has not been concluded.
your thoughts are appreciated , if someone experienced similar incidents. noting that the other three units with the same age never had similar incidents.
