Abstract: To keep a discharge pressure or a discharge flow rate of a pumping system that jets a fluid from a nozzle selected from a plurality of nozzles a set value every selected nozzle. A pumping system that jets the fluid from the nozzle selected from the plurality of nozzles is provided with: a piston pump as a positive-displacement pump; a permanent-magnet type synchronous motor as a rotational speed variable drive unit; a turret device as selecting arrangement; a discharge pipe; the nozzle; a controller that controls the rotational speed of the drive unit; a storage that stores control parameters and a target value of the discharge pressure corresponding to each nozzle; and a pressure sensor, wherein the controller controls the rotational speed of the drive unit by feeding back the discharge pressure using the control parameters corresponding to the selected nozzle to match the discharge pressure with the target value.

Abstract: To keep a discharge pressure or a discharge flow rate of a pumping system that jets a fluid from a nozzle selected from a plurality of nozzles a set value every selected nozzle. A pumping system that jets the fluid from the nozzle selected from the plurality of nozzles is provided with: a piston pump as a positive-displacement pump; a permanent-magnet type synchronous motor as a rotational speed variable drive unit; a turret device as selecting arrangement; a discharge pipe; the nozzle; a controller that controls the rotational speed of the drive unit; a storage that stores control parameters and a target value of the discharge pressure corresponding to each nozzle; and a pressure sensor, wherein the controller controls the rotational speed of the drive unit by feeding back the discharge pressure using the control parameters corresponding to the selected nozzle to match the discharge pressure with the target value.