Pump-controlled hydraulic circuits are more efficient than valve-controlled circuits, as they\neliminate the energy losses due to flow throttling in valves and require less cooling effort. Presently\nexisting pump-controlled solutions for single rod cylinders encounter an undesirable performance\nduring certain operating conditions. This paper investigates the performance issues in common\npump-controlled circuits for the single rod actuators. Detailed analysis is conducted that identifies\nthese regions in a load-velocity plane and the factors affecting them. The findings are validated by\nexperimental results. A new design is then proposed that employs a limited throttling valve alongside\ntwo pilot operated check valves for differential flow compensation to improve the performance.\nThe valve is of the flow control type and is chosen to have a throttling effect over critical regions;\nit has the least throttling over other operating regions, thus maintaining efficiency. Experimental\nwork demonstrates improved performance in a full operating range of the actuator as compared to a\ncircuit that uses only the pilot-operated check valves. This circuit is energy efficient and capable of\nrecuperating energy.
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