Major Power Outage 18 September 2018

Much has been said about the blackout on Tuesday morning. Thus far, these are the official findings

  • Disruption lasted for about 38 minutes, between 1:18AM and 01:56AM on the 18 September 2018.
  • 19 areas in Singapore were affected: Boon Lay, Choa Chu Kang, Clementi, Jurong, Pandan Loop, Aljunied, Geylang, Tanjong Rhu, Mountbatten, Kembangan, Bedok, East Coast, Ang Mo Kio, Bishan, Thomson, Mandai, Admiralty, Sembawang and Woodlands (~146,000 customers).
  • Caused by the tripping of power generation units belonging to Sembcorp Cogen and Senoko Energy.
  • Dubbed the worst major power outage since 2004.
  • Previous major blackout (albeit much smaller scale than this incident) was on 1 June this year confined to the CBD area.

We had one advanced energy logger on-site (an office in Cecil Street – CBD area), doing harmonics compliance measurement during the incident. Here, the trending graphs showed that frequency ‘dipped’ down to as low as 48.83 Hz. The journal logs showed that it returned to its normal operating range (49.5 Hz to 50.5Hz) in about 18 seconds (Nation-wide under frequency relays automatically kicked in for load shedding during these 18s).

Unfortunately, we did not use our higher-end equipment here (Dranetz HDPQ for instance). Hence the limited information (eg. Waveforms, detailed rms trends, etc could not be shown).

This particular office was not affected by the blackout.

Voltage & Frequency Trend