Feeder pumps are dimensioned based on the full system consumption flow with a margin for approx. 20% additional power, and the flow needed for flushing the automatic filter. Traditionally, the pumps are driven at full capacity, and the excess flow returns to the pump suction side through pressure control overflow valve. In practice, such full capacity is needed only occasionally. Because of the continuous operation with excessive power, energy is wasted for circulating fuel through pressure control overflow valve, noise levels are continuously high and the pump is subject to unnecessary wear.
Auramarine has addressed this issue by developing programmable logic control (PLC) with dynamic frequency control as an integrated part of the fuel supply system. The new system monitors and adjust the feeder pump outlet pressure constantly and precisely based on the needed output capacity.
Always optimised fuel pressure
This new, integrated control allows for more user-friendly and accurate monitoring and continuous automatic frequency adjustment to maintain an optimised fuel pressure. For example, the full power is approx. 2kW, while the idle mode power consumption with a dynamic frequency controller is in the range of one lightbulb. The intake power needed during operation cycle is lower and savings can be achieved. The generator will run less, reducing the fuel consumption and in turn reducing the wear of the fuel supply pumps.
Optimised power usage means less wear for the pump wearing parts, and therefore longer service intervals. This new integrated control logic will also enable condition based monitoring, and can be integrated to engine control room HMI or ship automation systems with a bus connection.
The Integrated pump control is an asset especially for systems using low viscosity fuels, such as ISO 8127:2017 DMA distillates, or for systems with operation profiles using fuel changeover procedures, but all types of fuel supply systems can benefit from its features.
The integrated PLC control will be available for Auramarine fuel supply units in Q1/2019.