Design Of Control System For Electro - Hydraulic Servo Test Bench Based On

Electro-hydraulic servo system is widely used in national defense and civilian industry as it has large power to weight-ratio, fast response speed, big load stiffness and high control precision. In this technology it is the goal of domestic and overseas continuous efforts and long-term pursuit that improving the dynamic response characteristics of electro-hydraulic control system to meet the demand for a variety of applications. Electro-hydraulic servo system is a nonlinear and time-varying system. It is the most active area for electro-hydraulic servo technology research that appling achievement of control theory to improve the control performance. It is common method to verify the effectiveness of various control strategies that simulating actual application system and environment and conducting large numbers of experiments by using electro-hydraulic servo test bench in laboratory. Contraposing existing electro-hydraulic servo control system integrated test bench, this paper completes the design of DSP control system, including hardware circuit design, software design, and PC monitor interface design. The main work are as follows:(1) Based on the analysis about the composition of experimental test bench and the system function, the hardware scheme of the control system is determined. This paper choses the DSP model, according to the modular design thought completes the hardware design, Modules includes the analog data acquisition module, analog output module, communication module, power supply module, etc.(2) In accordance with the requirements of test bench control function, the software scheme is determined with structured programming thought, including the main program, the timing interrupt service subroutine, communication receiving interrupt service subroutine. The main program achieves system clock initialization, peripheral initialization, settings of timing time and interrupt configuration; the timing interrupt service subroutine achieves open-loop characteristics test and closed loop control, including A/D conversion, D/A conversion, data transmission and PID control.(3) With CAN bus as the underlying network, communication between DSP and PC is implemented by formulating the communication protocol. The PC monitor interface is compiled by VB language, realizing the real-time monitoring of test bench control system. The PC monitor interface implements the password login, parameter setting, real-time data display, real time curve drawing, data saving and curve saving. At the same time the start and stop control buttons are also equipped.(4) Finally, the functional tests of various modules of the test bench control system are completed. The tests include input and output channels test, system communication function test. And the paper completes open-loop characteristic test and closed-loop control experiment. These tests verify the feasibility of test bench control system design.