Repeated cycles each consist of a pump down phase and a holding phase, wherein a start timepoint of each cycle is the timepoint when a rise in an inlet pressure of the pump is sufficiently large and the time extending between two consecutive cycle start timepoints is a cycle time. A control method includes determining a start of a next cycle during a present cycle, wherein it is preferable that the present cycle directly precedes the next cycle. The method further includes controlling the pump to accelerate to a maximum allowed speed during the holding phase of the present cycle before the start of the next cycle such that at the start of the next cycle full pump capacity is available.