Arc flash assessment at Cathedral Rocks Wind Farm

Cathedral Rocks Wind Farm, pictured, is 30km southwest of Port Lincoln in South Australia. The wind farm consists of 32 wind turbines and generates 64 MW of total power. Owner ACCIONA Energía asked Middleton Group to carry out arc flash assessment as per IEEE standards for the wind farm’s electrical assets, which ranged from main AC switchboards to DC battery systems. 

Our engineers gathered all the data for relevant electrical assets, using SKM PowerTools software to model various operating conditions in order to predict various arc flash faults, determine the arc-flash boundary (the distance at which a person without personal protective equipment may get a second-degree burn if an arc flash occurs) and the incident energy (the measurement of energy, typically measured in calories per square centimetre, as it strikes a surface, theoretically a worker standing at the switchboard with the panel doors open).  

The assessment helped identify safety hazards for HV and LV switchboards during arc flash faults and suggested appropriate actions to improve plant safety, including amending protection settings, identifying which switchboards needed to be completely de-energised for work to be carried out, specifying what personal protection equipment needed to be worn around each switchboard and outlining what arc flash safety labelling was needed to raise staff awareness of risks.