DEVELOPMENT AND RESEARCH OF A PHOTOELECTRIC MEASURING CONVERTER WITH DIGITAL FILTERING OF OPTICAL PULSE-CODE SIGNAL

Abstract

The specific nature of metallurgical production involves significant material and energy losses. It has been established that the main metal losses at the rolling mill occur due to the high inertia of photoelectric information channels for metal detection, which reduce the overall response time of the information and measuring system of the rolling mill. The operation of primary control means occurs under conditions of strong optical and electromagnetic interference, which sharply reduces the reliability of the primary information on the state of the controlled object. This leads to emergency situations in the operation of the rolling mill and, as a consequence, to significant material losses due to equipment failure and metal losses. Consequently, increasing the response time of photoelectric measuring transducers and the reliability of the primary information obtained is an urgent task. The use of analog information signals in measuring transducers is complicated by the presence of predominantly continuous disturbing effects, which is due to the specific nature of heat engineering production. The greatest noise immunity is provided by the use of discrete signals. In this case, encoding of the information signal allows to get rid of random analog and part of the impulse interference that do not fall into the frequency bandwidth window – to significantly reduce the total accumulated error during reception and to achieve real high noise immunity of the developed converter. Based on the adopted criterion of the optimality of the converter structure – high noise immunity, ensuring the reliability and accuracy of control in extreme conditions (criterion of the minimum error), the structure of the optical signal receiver, optimal according to the proposed criterion, was developed. To implement the developed principles, methods and means of increasing the reliability and speed of control, an algorithm for the operation of a discrete photoelectric measuring converter with digital filtration of a code-pulse optical signal as an element of the information system was compiled, and a hardware implementation of the device based on the proposed principles was developed.