Hydraulic Power Unit Explained: How Electric Hydraulic Pumps Drive Hydraulic Systems Hydraulic Power Units (HPUs) are the driving force behind many modern hydraulic systems. From factory presses to construction equipment, they supply the pressurized fluid needed to move heavy loads with precision. Explore the fundamentals of a hydraulic power unit and the role of electric hydraulic pumps. Understand components, working processes, and how to select the right HPU for your system.