Uncontrolled magnetically driven dosing pumps cause noise when the armature reaches the mechanical end stops. The reason for this is the impulse of the armature, which depends on the armature speed. A speed reduction before reaching the end stops could reduce the noise level. This requires a special modification of the time-dependent armature motion using variable energy supply. In order to control the armature motion independently from various inputs such as supply voltage, outlet pressure and liquid properties, the position has to be known. Sensorless position estimation is used, since it offers the determination of the armature position without modifying the simple pump design. The estimation is based on the evaluation of electrical values.
In order to show feasibility of position estimation in dosing pumps considering different control strategies, simulation based preliminary investigations are performed and validated with experimental results. For this purpose, a co-simulation of controller, electrical and mechanical system simulation and magnetic FEM simulation is used.