i want a variable discharge from a centrifugal pump. but the pressure should not vary. and also my input power consumption should go down. can anyone suggest me such drive and its details please...
Control the pressure by allowing the drive to modulate the pump based on pressure set point.
Control the flow with a modulating control valve with an input from a flow control.
Power consumption will vary based on flow volume/the amount of work the pump is doing.
Decreased flow demand=increased pressure=VFD ramping down to maintain setpoint=reduced power consumption.
Increased flow demand=decreased pressure=VFD ramping up to maintain set point=increased power consumption.
Don't know what your specific application is, but this scenario is very similar to a chilled water loop.
To avoid serious problems, make sure the system is correctly designed/engineered.