Switchgear Short Circuit Rating Studies
This Power Station was designed in the 1970’s when the fault current contribution made by induction motors into short circuits was not widely recognised.
Process Plant Protection Settings
When construction of a $60 billion LNG plant commenced, AEE was chosen to provide the time graded protection settings for the entire power system from the 240 V lighting and small power circuits up to the 150 MW gas turbine generators.
When this gold mine operator contacted AEE gold production was punctuated by unexplained MCC outages in the processing plant. After visiting the facility and meeting the electrical staff AEE developed the following remediation work package for application in each of the plant’s substations.
Protection Maloperation Investigations
Protection maloperations happen and the effects can sometimes be costly. AEE has successfully completed investigations into unexplained switchgear operations at power stations, substations and motor control centres.
Underground Mine Earth Fault Grading
This underground mine was supplied by an 11 kV distribution system with several kilometres of overhead lines. The overhead lines were subject to frequent faults due to lightning and bird strikes.
Underground Mine Earthing Study
AEE recommended an earth grid design for this remote mine’s Power Station that satisfied step and touch potential safety at the power station and at the adjacent fuel storage tank area.
Motor Starting Study
For this isolated 60 Hz power system, AEE determined the minimum number of diesel generators required for motor starting and the time interval between motor starts to optimise the system frequency and voltage profile.
Voltage Control Scheme
AEE developed two control strategies for the switching of five filter capacitor banks distributed along the length of a 33 kV mine feeder. One strategy was for the main control of the filter bank circuit breakers via a central PLC with fibre optic communications to each substation. The other strategy was for the back up control of each filter bank by an independent, dedicated numeric protection relay.