I agree 1000% and thats how we always do it. However per spec this is how they want it to operate.
The system will have two pumps that are 100% redundant and can be operated separately or in parallel. The pumps will be equipped with variable frequency drives and control valves that will modulate to maintain the desired pressure. The pressure controller will modulate the VFD as the primary means of control and the control valve as the secondary means of control to maintain minimum VFD current consumption while satisfying the flow rate setpoint. The pressure controller will have a low-speed limit on the VFD to prevent operation at inadequate pressure. (Low-speed limit on pumps TBD at startup). Alarming for both pumps, VFDS, and pressures will be provided. The feedwater control will allow the operator to modify the required pressure setpoint, switching of controller modes (auto and manual), and direct speed control of the pumps in manual mode.