KSB PumpDrive 2 - Page 102

8 Commissioning/Shutdown
102 of 212
PumpDrive 2
Sensorless differential pressure control with dynamic pressure compensation
(Sensorless Dyn Press Comp)
Q
p
Q
p
Q
∆p
1
2
3
Fig.72: Differential pressure control with dynamic pressure compensation in closed
system
1 Pump set with diagram of flow rate-dependent setpoint
2 Piping with diagram of pressure losses
3 Consumer with differential pressure diagram
In a closed hydraulic system, an almost constant differential pressure can be achieved
at the consumer through sensorless dynamic pressure compensation, without the
need for pressure sensors. The method is based on the characteristic curves of the
pump. Steep power curves are conducive to high process accuracy. The process is
suitable to a limited extent if sections of the power curve are constant over the flow
rate. It is activated by setting the Type of Control parameter (3-6-1) to Differential
Pressure (Sensorless) and setting the Dynamic Pressure Compensation Method
(3-9-3-1) to Flow Rate.
NOTE
Sensorless differential pressure control with dynamic pressure compensation does
not work if the Dynamic Pressure Compensation Method (3-9-3-1) parameter has
been set to Speed.
3-9-3-4
3-9-3-2
Q
P
1
2
3
Fig.73: Setpoint compensation curve for dynamic pressure compensation based on
flow rate
1 Flow rate independent setpoint 2 Setpoint Compensation
3 Compensated setpoint