Abstract: Since disruptive forces can be continuously exerted upon a rotor during a pulsatile flow through a pump with a magnetically mounted rotor (permanent magnets and addition control current coils), it is necessary to adjust position i.e. modify axial rotor position very quickly. The control current should only result in small amounts of losses. According to the invention, the current is pulse-width modulated by the control current coils by means of a set value predetermined by a controller which is arranged downstream from a position sensing system. If the set value is high, it is switched to a higher voltage level and the real value of the position sensing system is stored for a defined period of time, respectively beginning with the switching flank of the control current, and the position sensing system is disconnected during said period of time.

Abstract: Method for controlling an assist pump for fluid delivery systems with pulsatile pressure. If for example a heart assist pump is driven with a constant number of revolutions, it is achieved, that the blood is also delivered through the assist pump, even when the heart chamber is in the decontraction phase. With the present method it is achieved, that an assist pump only acts supportingly in the pressure phase of the main pump, in such a way, that the pressure difference between the input side and the output side of the assist pump is continuously determined and the number of revolutions of the assist pump is controlled in such a way, that the determined pressure difference does not fall below a predetermined value and the rate of flow does not sink below zero.

Abstract: Method for controlling an assist pump for fluid delivery systems with pulsatile pressure. If for example a heart assist pump is driven with a constant number of revolutions, it is achieved, that the blood is also delivered through the assist pump, even when the heart chamber is in the decontraction phase. With the present method it is achieved, that an assist pump only acts supportingly in the pressure phase of the main pump, in such a way, that the pressure difference between the input side and the output side of the assist pump is continuously determined and the number of revolutions of the assist pump is controlled in such a way, that the determined pressure difference does not fall below a predetermined value and the rate of flow does not sink below zero.

Abstract: Since disruptive forces can be continuously exerted upon a rotor during a pulsatile flow through a pump with a magnetically mounted rotor (permanent magnets and addition control current coils), it is necessary to adjust position i.e. modify axial rotor position very quickily. The control current should only result in small amounts of losses. According to the invention, the current is pulse-width modulated by the control current coils by means of a set value predetermined by a controller which is arranged downstream from at position sensing system. If the set value is high, it is switched to a higher voltage level and the real value of the position sensing system is stored for a defined period of time, respectively beginning with the switching flank of the control current, and the position sensing system is disconnected during said period of time.