The Research Of Servo-Valve Static Characteristic Test System Based On CAN Bus

Servo-valve is the key component of a hydraulic servo system, it must be tested strictly before delivery in order to guarantee the quality. Static and dynamic characteristic test is the main content of the test. In traditional way of servo-valve test, the whole test, including valve test and data process, is processed manually. The long time of the test leads to a low efficiency. As the quantity and variety grows, the traditional test has become a bottle-neck of servo-valve production.Most of existing domestic test systems are based on the form of computer plus data sample adapter, which is easy to realize, though its real time processing ability is poor and the signal is easy to be intervened. The most evident problem is the big error of flow measuring, and the signal is full of spike pulse, it must be processed by digital filter before it can be used.This subject is to design a automatic servo-valve static characteristic test system aims at solving the problems that exist, and provide corresponding software interface to facilitate the further development of data process program.The test oil circuit of"GB/T 15623.1-2003"is referenced and a test platform is made. According to the requirement, a new multi-purpose control circuit is designed, and realizes the experiment signal generation, data sampling and experiment automatic control. CAN bus is applied as the data bus between control circuit and computer, and CANopen protocol is realized as the protocol of CAN bus. Master-Slave structure is adopted as system model, the computer is served as the master while the control circuit is served as the slave. Because of the rational division of labor, the computer and control circuit realize the mutual benefit. Finally, the automatic test is realized and the reliability and real time process ability are improvedValidated by experiment, this testing system realizes servo-valve static characteristic automatic test, and the repeatability is within 5%. At the same time, the reliability and interference immunity are improved significantly.