Ozhenko Y. Models, methods and means of diesel engine fuel injection system improving on the basis of piezoelectric transducers

The dissertation research is devoted to solving an actual scientific and practical problem of improving marine diesel engines fuel injection system equipped with hydraulic actuators by means of piezoelectric transducers. The paper analyzes the current state of computerized fuel injection control systems, which showed that a further increase in the efficiency of such control systems is possible by improving the actuators, by eliminating the hydraulic drive. A further analysis of existing actuator types showed the futility of their further improvement in the design-technological direction. Showed the possibility of using piezoelectric drives as actuator in high-pressure fuel systems; noted drawbacks of piezoelectric transducers, which restrained the use as piezodrives on marine engines. Based on these circumstances, formulated the goals and objectives of the study, aimed at creating theoretical and practical provisions that will allow the development of high-pressure fuel system actuators piezoelectric drives. The method of improving computerized marine diesel engine fuel injection control system by introducing actuators based on piezoelectric transducers, which make it possible to increase the fuel economy, was further developed. For the first time, introduced models of the component designs of a computerized fuel injection control system based on actuator drive which based on piezoelectric stack, allowed to obtain large valve movements in the fuel injection control unit with the necessary effort and time of the transition. For the first time, introduced models of the designs of components of a computerized fuel control system based on actuator drive which based on piezoelectric rotary engines which allowed to increase the movement of the valve in the control unit fuel supply. Their modeling and calculation of the main indicators was carried out. The analysis of fuel injection computer control system components constructions models based on actuators which based on piezoelectric converters showed the oscillatory nature of the system, which negatively affects the system reliability, leads to a deviation of the fuel injection curve from a given type, and as a result, to a decrease in efficiency. Based on these circumstances, the task is to develop methods for eliminating unwanted vibrations. The further development of the fuel injection control unit spool positioning model due to the use of a fuzzy regulator, which made it possible to reduce internal oscillations of the system, thereby increasing the guaranteed safety of the fuel injection system. The further of piezoelectric transducer models with feedback due to the first-time obtained circuit design and functional models of piezoelectric transducers stack with feedback, which made it possible to design fuel injection systems without internal oscillations of the system, that is, with increased reliability. Designed and patented designs of actuators on the basis of piezoelectric stack and piezoelectric rotary engines. Experimental studies have been carried out. Keywords: electronically controlled diesel engine fuel injection system, actuator, piezoelectric transducers.