Abstract:Direct drive pump-controlled servo hydraulic press which combines the fixed displacement pump and permanent-magnet motor together is a new electromechanical integration power unit of energy-saving. This hydraulic servo system is controlled by different pump's flow, which is realized by changing the speed of the motor. Comparing with the traditional valve-controlled system, it has the advantages of small volume, energy saving, high efficiency, high reliability. So it is considered to be a new direction of electric-hydraulic drive technology. Taking the drawing process as example,based on the principle of energy conservation, the energy comparison experimental study of ordinary hydraulic and servo hydraulic was carried out.The servo controlled hydraulic pump main energy saving loops: volume control, standby stops,were analyzed. The prototype testing results indicate that the direct drive pump-controlled servo hydraulic press saves over 20% energy compared to the traditional hydraulic press.