Hydraulic power generation pump control

A dynamic testing system comprising:

• at least one test station, each configured to apply a force and/or a displacement to a test subject using hydraulic actuators during performance of a test;
• a hydraulic power unit including a plurality of hydraulic pumps configured to produce a variable main flow of hydraulic fluid that drives the hydraulic actuators of the at least one test station during the performance of at least one test;
• and
• at least one controller configured to:
• obtain at least one test flow profile, each identifying a hydraulic fluid flow demand estimate over time corresponding to the performance of one of the at least one test;
• and
• produce the variable main flow of hydraulic fluid using a plurality of unique subsets of the plurality of hydraulic pumps during the performance of the at least one test, each unique subset being selected based on the at least one test flow profile.

A method of controlling a hydraulic power unit of a dynamic testing system using at least one controller, the hydraulic power unit including:

• a reservoir containing hydraulic fluid;
• a main output though which a main flow of the hydraulic fluid is discharged;
• a pressure sensor having a pressure signal that is indicative of a main pressure of the main flow;
• a plurality of variable displacement hydraulic pumps each configured to drive a portion of the main flow, each variable displacement hydraulic pump comprising:
• a plurality of piston pumps;
• a motor having an activated state in which the motor drives cyclical change to a working volume of each piston pump, and a deactivated state;
• and
• a pressure setpoint that is selectable between:
• a range of inoperable pressure setpoints that are below an anticipated operating range of the main pressure, at which the variable displacement hydraulic pump does not contribute to the main flow;
• and
• an operable pressure setpoint that is within the anticipated operating range of the main pressure, in which the variable displacement hydraulic pump is driven to contribute to the main flow,
• the method comprising controlling one of the variable displacement hydraulic pumps comprising:
• operating the variable displacement hydraulic pump for a first predetermined period while the pressure setpoint is set to a first inoperable pressure setpoint within the range of inoperable pressure setpoints;
• and
• operating the variable displacement hydraulic pump while the pressure setpoint is set to the operable pressure setpoint.