Method of and control for monitoring and controlling an electric motor for driving a pump

An electric motor for driving a pump, wherein the electric motor comprises:

• a motor control, the electric motor being configured as an electronically commutated electric motor, the motor control being configured with a program to drive the pump with current values which reflect a profile of winding current of the electric motor and, irrespective of whether they can be associated with an instantaneous maximum of the current profile, are included in determining an average value of current values within a time interval, the average value being a motor control input parameter, and the time interval being greater than a period duration that results due to system-inherent periodically recurring pressure fluctuation in a feed circuit of the pump, wherein the current values are measured at a base point of a converter of the electric motor;
• wherein a maximum permissible value for a motor feed current predetermined by the motor control is reduced if the average value of the current values measured is greater than the predetermined reference value;
• and wherein the maximum permissible value for the motor feed current is reduced by a difference between the average value and the predetermined reference value.

A method of monitoring an electric motor serving to drive a pump, wherein within a time interval current values are measured, an average value of the current values measured is determined and said average value is compared to a predetermined reference value, wherein the method extends to controlling the electric motor, wherein the current values measured reflect a profile of a winding current of the electric motor and, irrespective of whether they can be associated with an instantaneous maximum of the current profile, are included in determining the average value, wherein the average value is considered by a motor control as input parameter, and wherein the time interval is greater than a period duration resulting due to system-inherent periodically recurring pressure fluctuations in a feed circuit of the pump, wherein a maximum permissible value for a motor feed current predetermined by the motor control is reduced if the average value of the current values measured is greater than the predetermined reference value, and wherein the maximum permissible value for the motor feed current is reduced by a difference between the average value and the predetermined reference value.

A method of monitoring an electric motor serving to drive a pump, wherein within a time interval current values are measured, an average value of the current values measured is determined and said average value is compared to a predetermined reference value, wherein the method extends to controlling the electric motor, wherein the current values measured reflect a profile of a winding current of the electric motor and, irrespective of whether they can be associated with an instantaneous maximum of the current profile, are included in determining the average value, wherein the average value is considered by a motor control as input parameter, and wherein the time interval is greater than a period duration resulting due to system-inherent periodically recurring pressure fluctuations in a feed circuit of the pump, wherein a maximum permissible value for a motor feed current predetermined by the motor control is reduced if the average value of the current values measured is greater than the predetermined reference value, and wherein the maximum permissible value for the motor feed current is reduced at the most to half of the predetermined reference value.