Gain self-adjustment type supercoiling slip form control method for electro-hydraulic positioning servo system

Abstract

The present invention discloses a gain self-adjustment type supercoiling slip form control method for an electro-hydraulic positioning servo system. By utilizing the information of an existing system model, a model-based feed-forward control law is led into the control algorithm of a traditional supercoiling slip form, so that the system servo accuracy is improved. The gain of a controller is updated in real time based on the self-adapting rule. In this way, the exact boundary of the system modeling nondeterminacy is not required to be apriori known. The conservative property due to the artificially preset control gain related to the above boundary in the conventional algorithm can be avoided. Based on the Lyapunov stability theory, the global stability of the closed-loop system is proved. The tracking error of the system asymptotically converges to be in an arbitrarily small range near to zero within the finite period of time. Meanwhile, the convergence speed and the boundary of the steady-state error can be adjusted through parameters.

Description

technical field [0001] The invention relates to the technical field of electro-hydraulic servo control, and mainly relates to a super-helical sliding mode control method for gain self-adjustment of an electro-hydraulic position servo system. Background technique [0002] The electro-hydraulic servo system has outstanding advantages such as high power density, large output force / torque, and strong anti-load rigidity, and has been widely used in many important fields. With the rapid development of modern industrial technology, the servo precision requirements for electro-hydraulic servo systems are also getting higher and higher. The electro-hydraulic servo system is a complex nonlinear control object. There are system parameter uncertainties caused by changes in the working environment (such as temperature changes) and component wear, as well as uncertain nonlinearities such as nonlinear friction and external load interference. These Modeling uncertainty will seriously deter...

AI Technical Summary

Problems solved by technology

Traditional sliding mode control can deal with all bounded modeling uncertainties and obtain asymptotic tracking performance, but its biggest disadvantage is that the existing discontinuous sign function will cause controller chattering, which is not suitable for practical systems. Allowed

In order to solve the problem of discontinuity in the traditional sliding mode controller, a continuous saturation function can be used instead of a discontinuous sign function, which can effectively avoid control input chattering, but it can only ensure that the tracking error is bounded, and the asymptotic tracking performance is lost

In addition, the high-order sliding mode controller can also obtain asymptotic tracking while ensuring the continuity of the controller, but the design of the controller requires the information of the derivative of the sliding mode variable, which is often considered unknowable in practice, so Difficult to implement

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