Damen Schelde Naval Shipbuilding has delivered two Perusak Kawal Rudal (PKR) guided missile frigates designated for the Indonesian Navy. Bakker Sliedrecht was responsible for the electrical auxiliary propulsion system. The frequency drives of this propulsion system are directly connected to the power grid while complying with the EMC regulations.
Key components of the electrical auxiliary propulsion system are two electric propulsion motors from Indar and two water-cooled variable-frequency drives with active front ends. Both frequency drives are cooled by one water-cool unit to save weight, space and costs.
After assembling the electrical drive systems in our workshop, the installations were delivered to Damen Shipyards, where one of the ship segments was built. Damen installed the electrical propulsion system after which Bakker Sliedrecht conducted an installation check on the finished ship segment. Then, the ship segment was shipped to Indonesia were all ship segments were connected to each other.
Each frequency drive is connected to the vessel’s power grid, without the use of a transformer, to save weight and space. Without certain measures, this direct (conductive) coupling can cause unwanted effects on sensitive operational equipment connected to the grid. Bakker Sliedrecht created smart filter techniques to mitigate the disturbance levels in order to comply with the IEC- and Navy regulations. Prior to realization, model based simulations were used to prove this brand new design. A selective earth fault detection is also included in this design.