Are there advantages to using fixed displacement pumps vs. variable displacement pumps?
Fixed displacement pumps are generally used when the hydraulic flow requirements are continuous and the flow rate is fixed – a constant speed winch, for example. Variable displacement pumps are generally used when the flow demand varies considerably (when used as a supply to a valve package controlling a manipulator or tool suite, for example) – when the flow requirements drop, the pump displacement drops to a level required to maintain system pressure and the electrical power demand drops accordingly. Since all Tecnadyne hydraulic pumps are powered by variable speed DC brushless motors, it is also possible to use a fixed displacement pump as a variable displacement pump – simply vary the motor speed as the hydraulic flow requirements increase and decrease. However, this does require that use the system hydraulic pressure to close the motor speed control loop. If you have any questions, please contact the factory.
