Zakharenkov D. A computer system for software control of fuel-air mixture supply processes of power units under conditions of incomplete information

The dissertation is devoted to the development of theoretical foundations and practice of building computer systems for controlling fuel-air mixture supply processes based on the processing of indirect measurement data under the conditions of random disturbances, to the study of uncertainties and speed of hardware and information technology for monitoring cylinder capacities, as well as to the development of methods for reducing uncertainties and increasing the speed of application software. As a source of input information, the computer system uses a frequency-modulated signal of the speed of rotation of the crankshaft. Solving this scientific and applied problem will ensure fuel economy, reduce the probability of overloading individual cylinders, increase the life of the power unit and reduce the costs of prevention, maintenance and repair. The use of modern injectors, which have means of electrohydraulic or piezoelectric control of the fuel-air mixture supply processes, allows you to develop the conceptual principles of software movements of the hardware in order to achieve the identity of the cylinder capacities of the power units. The methods of the theory of measurements, probabilities and mathematical statistics were used when processing experimental data in the form of a series of measurements with multiple observations. Hardware and application software uncertainties that belong to category A have been identified. The theoretical principles and methodology of the synthesis of hardware means for processing the data of indirect measurements using the quadratic quality criterion and reference mathematical models of the components whose delay is known have been developed. Based on the methods of similarity theory and signal graph theory, the transfer functions of individual components of the computer system for processing indirect measurement data were obtained. A computer system for software control of the processes of supplying the fuel-air mixture to the cylinders with specified uncertainty and processing speed of indirect measurement data was built. The object of research is the process of building the hardware and software of a computer system for controlling the supply of a fuel-air mixture with feedback based on the state of the cylinder capacities of the power unit based on the processing of indirect measurement data in the form of a frequency-modulated signal of the speed of rotation of the crankshaft, and also under the conditions of accidental interference with its components. The subject of research is mathematical models, measurement methods, algorithmic and application software, hardware structures and components. The methods used are: system analysis and the theory of automatic control under conditions of incomplete information; collection, processing, encoding and decoding of information; similarity theory and signal graph theory; theories of probability, mathematical statistics and theories of random processes; theory of measurements, in particular, the informational approach. Computer simulation methods were used in studies of speed and uncertainty of signal conversion hardware. The scientific novelty of the obtained results lies in the development of the theoretical basis for the construction of hardware and software tools for a computer system of closed-loop control of the processes of supplying the fuel-air mixture to the cylinders of a diesel generator based on the processing of indirect measurement data in the form of a frequency-modulated signal of the speed of rotation of the crankshaft under operating conditions random interference.