Design of Digital Hydraulic Transformer and Experimental Research on Its Steady State Characteristics

doi:10.3901/JME.2022.08.266

Abstract

Abstract: A digital hydraulic transformer(DHT) is proposed, which combines multiple binary displacement ratio pump/motor flow units together and uses a mechanical connection to make them rotate synchronously. A high-speed on-off valve group is connected to the inlet and outlet of each flow unit, and the on-off state of each valve group corresponds to a binary number. By controlling the digital status of the inlet and outlet valve groups, different transformation ratios can be adjusted to achieve different pressure output. According to the working principle of DHT, the structural design and mathematical modeling were performed, and a prototype was manufactured. Finally, a test platform is built to verify its steady state characteristics. The results show that the proposed digital hydraulic transformer can change its voltage with the change of digital control quantity, which verifies the feasibility and practicability of its voltage transformation principle. DHT has the characteristics of discrete digital components, simple and easy to control, and has a large voltage range. It can be used as a secondary regulating element in a hydraulic constant pressure network system to drive a linear load. It can also recover potential energy and pressure energy at the load end, which is of great significance for improving the efficiency of the hydraulic system.

Key words: hydraulic transformer, constant pressure network, high-speed on-off valve, operating characteristics

CLC Number:

TG156

LIU Tao, SUN Renfu, HAN Yan, ZHAO Dingxuan. Design of Digital Hydraulic Transformer and Experimental Research on Its Steady State Characteristics[J]. Journal of Mechanical Engineering, 2022, 58(8): 266-273.

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