As a matured technique used in many fields,the distributed computer system is still a new management method for the aeronautical electrical power distribution system in our country. In this paper, a novel aircraft ele...As a matured technique used in many fields,the distributed computer system is still a new management method for the aeronautical electrical power distribution system in our country. In this paper, a novel aircraft electrical power distribution system based on the distributed computer system is proposed. The principles, features and structure of the aircraft electrical power distribution system and the distributed computer system named electrical load management system (ELMS) are studied. The ELMS composed of four electrical load management centers (ELMCs) and two power source processors (PSPs) operates in the 1553B buses. Principles of the ELMCs and the PSPs are introduced. With the application of the distributed computer system, the aircraft electrical power distribution system is simple, adaptable and flexible.展开更多
The rapid pace of change in the wide band gap(WBG)power semiconductor area has led to an explosion in potential uses for WBG devices in a huge variety of applications.The applications include automotive,aerospace and ...The rapid pace of change in the wide band gap(WBG)power semiconductor area has led to an explosion in potential uses for WBG devices in a huge variety of applications.The applications include automotive,aerospace and traction applications,as well as grid related or charging systems,with the potential to provide paradigm shifts in performance and efficiency over Silicon devices in current use today.Despite these exciting developments,however,there are still many outstanding challenges for both researchers and industry to solve before WBG technology becomes pervasive.In this paper we will explore some of these challenges and highlight the strengths of WBG devices,some of the specific issues for machine drives and develop some potential solutions for future developments in power electronics.展开更多
Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, mot...Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft.展开更多
The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder ...The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder flow characteristics.This paper reviews the development history and characteristics of gas exchange types,as well as the current state of theory and the validation methods of gas exchange technology,while also discusses the trends of cutting-edge technologies in the field.This paper provides a theoretical foundation for the optimization and engineering design of gas exchange systems and,more importantly,points out that the innovation of gas exchange types,the modification of theoretical models,and the technology of variable airflow organization are the key future research directions in this field.展开更多
文摘As a matured technique used in many fields,the distributed computer system is still a new management method for the aeronautical electrical power distribution system in our country. In this paper, a novel aircraft electrical power distribution system based on the distributed computer system is proposed. The principles, features and structure of the aircraft electrical power distribution system and the distributed computer system named electrical load management system (ELMS) are studied. The ELMS composed of four electrical load management centers (ELMCs) and two power source processors (PSPs) operates in the 1553B buses. Principles of the ELMCs and the PSPs are introduced. With the application of the distributed computer system, the aircraft electrical power distribution system is simple, adaptable and flexible.
文摘The rapid pace of change in the wide band gap(WBG)power semiconductor area has led to an explosion in potential uses for WBG devices in a huge variety of applications.The applications include automotive,aerospace and traction applications,as well as grid related or charging systems,with the potential to provide paradigm shifts in performance and efficiency over Silicon devices in current use today.Despite these exciting developments,however,there are still many outstanding challenges for both researchers and industry to solve before WBG technology becomes pervasive.In this paper we will explore some of these challenges and highlight the strengths of WBG devices,some of the specific issues for machine drives and develop some potential solutions for future developments in power electronics.
文摘Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft.
基金funded by the National Natural Science Foundation of China(Nos.52206131,U2233213and 51775025)the National Key R&D Program of China(2022YFB2602002,2018YFB0104100)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(LQ22E060004)the Science Center of Gas Turbine Project,China(No.P2022-A-I-001-001)。
文摘The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder flow characteristics.This paper reviews the development history and characteristics of gas exchange types,as well as the current state of theory and the validation methods of gas exchange technology,while also discusses the trends of cutting-edge technologies in the field.This paper provides a theoretical foundation for the optimization and engineering design of gas exchange systems and,more importantly,points out that the innovation of gas exchange types,the modification of theoretical models,and the technology of variable airflow organization are the key future research directions in this field.
