Evaluation of performance of automatic emergency protection systems

Abstract

Introduction. Emergency protection systems are an indispensable element of modern automated control systems for fire and explosion hazardous technological processes. The protection of personnel, process equipment and the environment depends on their timely operation. Therefore, the methodology for quantifying the performance of the Emergency Protection System in the design and analysis is of undoubted practical interest. Targets and goals. The goal is to develop an algorithm and methodology for quantifying the response time of the protection system in the pre-emergency mode of operation of a technological facility. The tasks include the formation of mathematical models for calculating the time parameters of the elements that make up the Emergency Protection System. Methods. Methods of mathematical analysis and modeling of emergency protection systems are used. Results and discussion. The functions of the Emergency Protection System and the regulatory requirements for their performance depending on their safety class of hazardous production facilities are considered. A generalized algorithm for the formation of the Emergency Protection System is considered, taking into account the requirements for its speed. Using the typical structure of the Emergency Protection System as an example, an expression was obtained for the delay time when it performs the functions of an alarm and the operation of automatic shut-off and shut-off devices. According to technical sources, the approximate time parameters of the elements of the Emergency Protection System are given. The method of quantitative assessment of the response time is considered using the example of an emergency protection system designed to detect gas contamination of a production facility due to depressurization of process equipment, the formation of control signals when the concentration of combustible gases reaches a pre-explosive level, the activation of an alarm, and the operation of valves that block the access of combustible gas to a process facility. Mathematical expressions for calculating the parameters are determined, which allow estimating the total response time of the Emergency Protection System and its compliance with the safety condition for the normatively set time. Conclusions. The considered technique can be used in practice for a preliminary assessment of the response speed of the Emergency Protection System, as well as in the educational process for carrying out practical and laboratory work in the study of industrial automation systems to prevent fire and explosion. Keywords: emergency protection system, protection response time, pre-emergency mode of operation, accident.