DEVICE OF CONVERSION VOLTAGE FOR CONTROL COOLING DETAILS BASED ON THE FUZZY LOGIC

Abstract

Simulation of control parameters calculating process in the problem of cooling the parts surfaces machined on CNC equipment is considered in the article. A fuzzy model for determining the transmitted to the thermoelement current to control surfaces details cooling intensity proposed in the article. The fuzzy model consists of four steps. At the first step, the calculation of the degrees of the membership functions is produced. Input membership functions are having a triangular shape, and the output variable is represented by a singleton function. The second step, the degrees of the premises of the twenty-seven fuzzy rules is calculated. The third step, the eleven levels of conclusions of fuzzy rules is calculated. At the fourth step, defuzzification a crisp value from a simplified fuzzy inference is derived. After that, the scaling ratio and the output voltage level are determined. Also the condition of equality of the collector current for the calculated value is checked. If this condition is not implemented, the level of the output voltage is recalculated, until the set condition is fulfilled. The main problem in the system operation is the voltage calculation at the microcontroller output corresponding to the required current on the thermoelement with the maximum speed. To provide voltage calculating high speed in device was made on a field-programmable gate array (FPGA).Defuzzification in the fuzzy inference is based on a simplified fuzzy inference. The explaining the essence of the proposed technical solution numerical modeling is presented in the article. Timing diagrams of the cooling control device and voltage-current conversion devices in the cooling control system are presented in the article.