Tiny discharge gap bi-feedback adaptive analytic fuzzy servo control method

Abstract

The invention discloses a tiny discharge gap bi-feedback adaptive analytic fuzzy servo control method, and belongs to the technical field of non-traditional micromachining. In the method, interpolar voltage or current signals which are fed back in real time are compared with a control target center so as to obtain signal errors and the change of the errors; a self regulating factor of an analytic fuzzy control rule in the whole field is dynamically adjusted, and the discharge gap servo control performance is improved; and then, in order to adapt to machining conditions and control errors introduced by process random change, a discharge statistics and parameter correction feedback channel is utilized to store and count an open circuit rate and a short circuit rate, and a fast convergence algorithm directly proportional to the open circuit rate and the short circuit rate is adopted, so that the control target center and an electrode advancing and retreating speed scale factor adaptively tend to be optimal simultaneously, and the open circuit rate tends to be equal to the short circuit rate and is the minimum, namely the discharge rate tends to be optimal. The method realizes the quickness, stability and accuracy of tiny discharge gap servo control and improves micro electrical discharge machining efficiency.

Description

technical field [0001] The invention belongs to the technical field of micro-special processing, and in particular relates to a double-feedback self-adaptive analytical fuzzy servo control method for a micro discharge gap. Background technique [0002] Micro-EDM is a machining process that maintains a small gap between the tool electrode and the workpiece for electrical discharge erosion. The servo control effect of the tiny discharge gap directly determines the effect of the micro EDM. Due to the small discharge area and discharge energy, and the rapid change of the state of the gap between electrodes, many influencing factors and large randomness, it is difficult to control the small discharge gap with high precision servo control. Different from the servo control problems of position, speed, temperature, pressure, etc., this nonlinear and time-varying tiny discharge gap cannot be described by an accurate mathematical model. The difficulty of its servo control is to contr...

AI Technical Summary

Problems solved by technology

However, the control objectives and control rules of traditional fuzzy control methods are determined based on experience, and it is difficult to achieve optimal control without theoretical basis.

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