Sensorless pressure control of centrifugal pumps

A converter-fed system is proposed which successfully estimates and regulates the operational state of the pumping process without excess sensors. Sensorless control provides such advantages as cost savings resulting from exclusion the need in sensor incorporation in the drive and the driven system; increased reliability due to the absence of additional components, such as sensors, cables, connections that can cause malfunction; and fewer maintenance and data exchange operations. Such benefits are based on adjustable models that can be currently modified and corrected along with the test measurements in the system with known characteristics. Adjustable models describing the driven process could be added to the control scheme of the variable speed drive to exclude additional measurements for control.