Abstract
The relevance of the study is to develop an effective system for controlling the pressure in the air supply in motorised breathing apparatus to ensure effective protection of employees from dangerous aerosols and improve their health. The goal was to create an automated air pressure control system in a motorised breathing apparatus using a proportional-integral-derivative controller. For this purpose, the simulation method was used. In order to avoid unforeseen situations of deterioration of the level of protection, the structure of the pressure control system of a motorised respirator has been developed with the selection of the appropriate controller based on the obtained dependences of the influence of the parameters of the breathing mode and the amount of pressure in the under-mask space of the respirator, which ensures an appropriate comfortable mode of operation. This allowed developing a simulation model with a PID controller that would provide the appropriate pressure values within the permissible limits (50-370 Pa). It is proved that the proportional-integral-derivative controller maintains the pressure in the respirator mask within certain limits both with an increase and with a decrease in the control signal, preventing excessive fluctuations in the controlling variable, which leads to an extension of the service life of the filter elements and a reduction in electricity consumption for the operation of the fan motor. Based on modelling the operation of the pressure control system in different modes of operation, it is shown that when using a PID controller with defined parameters, the system provides compensation for changes in air pressure in the under-mask space of the respirator in different breathing modes of the user. The results can find practical applications in the field of safety and health, in industrial environments where workers are at risk of inhaling dangerous aerosols, such as toxic particles, gases, or other harmful substances