Generally speaking, hydraulic control systems can be divided into two different driving concepts. The first one is the well-known hydraulic valve-controlled system and the second one is the pump-controlled system. The...Generally speaking, hydraulic control systems can be divided into two different driving concepts. The first one is the well-known hydraulic valve-controlled system and the second one is the pump-controlled system. The former possesses the feature of fast dynamic response. However, the poor energy-saving performance is its major fault. On the contrary, the hydraulic pump-controlled system has the significant advantage of energy-saving which meets the current demand in modem machine design. In this paper, the simulation analysis using MatLab/SimuLink and DSHplus software for a newly developed energy-saving hydraulic tube bender is conducted. Instead of the conventional fixed displacement hydraulic pump, the new hydraulic tube bender utilizes an internal gear pump with AC servomotor as its driving power source. In the new energy-saving hydraulic circuit, the use of conventional pressure relief valve and unloading valve are no longer necessary since the demanded flow-rate and pressure output can be precisely obtained by continuously changing the speed of the AC servomotor. In addition, two closed-loop control schemes using fuzzy sliding-mode controller are adopted and compared. To compare the energy-saving control systems, such as load-sensing control system, constant supply pressure control scheme and conventional hydraulic control scheme. Furthermore, the simulation results also show that the newly developed hydraulic tube bender can save up to 43% of energy consumption in a working cycle as compared to the conventional hydraulic tube bender.展开更多
Measures of individualisation and integration offer a great potential for further development and optimisation in hydraulic drive technology. Advantages are seen especially for energy efficiency and functionality. To ...Measures of individualisation and integration offer a great potential for further development and optimisation in hydraulic drive technology. Advantages are seen especially for energy efficiency and functionality. To exploit these benefits the independent metering technology appears to be very attractive which motivates the extensive research on this topic during the last decade. This article starts with a brief overview on common hardware arrangements and general control approaches. Furthermore an approach to the safety evaluation of novel independent metering systems is given. Afterwards different application examples are presented, such as a cardboard packaging press in the area of stationary machines and in the fields of mobile machines a working implement of an excavator and an active steering system for tractors. The article ends with a brief summary of the valve requirements for independent metering.展开更多
文摘Generally speaking, hydraulic control systems can be divided into two different driving concepts. The first one is the well-known hydraulic valve-controlled system and the second one is the pump-controlled system. The former possesses the feature of fast dynamic response. However, the poor energy-saving performance is its major fault. On the contrary, the hydraulic pump-controlled system has the significant advantage of energy-saving which meets the current demand in modem machine design. In this paper, the simulation analysis using MatLab/SimuLink and DSHplus software for a newly developed energy-saving hydraulic tube bender is conducted. Instead of the conventional fixed displacement hydraulic pump, the new hydraulic tube bender utilizes an internal gear pump with AC servomotor as its driving power source. In the new energy-saving hydraulic circuit, the use of conventional pressure relief valve and unloading valve are no longer necessary since the demanded flow-rate and pressure output can be precisely obtained by continuously changing the speed of the AC servomotor. In addition, two closed-loop control schemes using fuzzy sliding-mode controller are adopted and compared. To compare the energy-saving control systems, such as load-sensing control system, constant supply pressure control scheme and conventional hydraulic control scheme. Furthermore, the simulation results also show that the newly developed hydraulic tube bender can save up to 43% of energy consumption in a working cycle as compared to the conventional hydraulic tube bender.
文摘Measures of individualisation and integration offer a great potential for further development and optimisation in hydraulic drive technology. Advantages are seen especially for energy efficiency and functionality. To exploit these benefits the independent metering technology appears to be very attractive which motivates the extensive research on this topic during the last decade. This article starts with a brief overview on common hardware arrangements and general control approaches. Furthermore an approach to the safety evaluation of novel independent metering systems is given. Afterwards different application examples are presented, such as a cardboard packaging press in the area of stationary machines and in the fields of mobile machines a working implement of an excavator and an active steering system for tractors. The article ends with a brief summary of the valve requirements for independent metering.
