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Magneto serves as the ignition source in the combustion process of piston aircraft engines. Typically, spark-ignition aircraft like the Cessna 172SP are equipped with two ignition systems (dual magnetos). Dual magnetos are installed so that if one system fails, the aircraft can still continue its flight. During the engine startup process, the magneto plays a significant role as the ignition source for the initial combustion before the aircraft engine comes to life. In the case experienced by pilots at the Indonesian Civil Pilot Academy Banyuwangi, starting the engine became challenging when the aircraft had been previously used for a flight. Therefore, this research is conducted to address the underlying causes of this issue. The parameters examined in this research include outside air temperature (OAT), Cylinder Head Temperature (CHT), and Exhaust Gas Temperature (EGT). Data were collected regarding the duration of the engine startup process. The duration time for starting the engine was found to be the highest at an exhaust gas temperature of 135 °F, a cylinder head temperature of 180 °F, and an outside air temperature of 35 °F, with a duration time of 6.8 seconds. Conversely, the shortest engine startup duration was observed at an exhaust gas temperature of 75 °F, a cylinder head temperature of 75 °F, and an outside air temperature of 26 °F, resulting in a duration time of 1.6 seconds. [ABSTRACT FROM AUTHOR]

Apart from the various technical issues, voltage and current spikes have always been the challenges of vehicular circuit designers. This paper presents a protection scheme against the possible damaging effects of an overcurrent phenomenon. The proposed circuit is capable of continuously measuring the magnitude of phase current through the motor windings, and compares the same with the predefined reference current. Depending on the comparison, it generates a signal and sends the same to the microcontroller and the dedicated IR3230 Brushless DC controller for protection. The functionality of the proposed scheme was supported with experimental validations. [ABSTRACT FROM AUTHOR]

The article presents research on the impact of a 359 compression-ignition engine starting at low ambient temperatures. This engine is used in vehicles such as STAR 200, 244, and 226. The purpose of these tests was to determine the amount of wear depending on the ambient temperature and the number of starts, as well as to compare the wear at start-up with the wear occurring during tests on the dynamometer (long-term test for reliability) and wear occurring during the operation of the engine in the vehicle, and the impact of the number of starts and ambient temperature on diesel engine for the life of the vehicle to be repaired. The results of the author’s research showed that a minimum of the number of starts at low ambient temperatures has an impact on the number of kilometers driven by the car during operation to replace the cylinder liners (engine repair). Apart from the Polish armed forces and armies of other countries in which this type of vehicle is still used, the direct recipients of the research results are also other entities from the logistics transport sector for which further use of this power unit especially at low ambient temperatures is of fundamental economic importance.

This study is aimed at revealing the dynamic response characteristics of a power-split hybrid electric vehicle (HEV) during the mode transition process with the engine starting. In this paper, for a hybrid powertrain system whose engine is directly connected to a compound power-split transmission, the equivalent lever method is first used to analyze the mode transition process with the engine starting. Then, based on the theoretical formulations and lookup tables, a dynamic model of the compound power-split HEV is established in detail, taking into consideration the engine ripple torque, battery-motor characteristics, dynamic meshing force between gears, and shaft spring-damping characteristics. The powertrain dynamic model is verified by a bench test. Moreover, taking the vehicle jerk and engine starting time as the evaluation indexes of the dynamic response characteristics, the influencing factors of the dynamic response characteristics in the engine starting process are analyzed comprehensively from the aspects of the engine, battery-motor, and engine starting condition. Finally, the engine starting process is synthetically optimized based on the obtained impact law of different influencing factors. The simulation results show that the synthesis optimization method can effectively reduce vehicle jerks and the engine starting time and improve driving comfort during the engine starting process.

Experimental research is essential in the development of a hybrid electric vehicle. In this study, a bench test was conducted for a compound power-split hybrid electric vehicle (PSHEV) to analyze the real dynamic characteristics of its components and the factors of system shock and vibration during the engine start-up process. Firstly, the mode switching process with an engine start-up was divided into four stages by the lever method. The basic control strategy of mode switching with engine start-up was formulated and tested on a bench test platform. Secondly, based on the bench test data, the output characteristics of the battery motor, engine, and driveshaft were analyzed in detail. The main variable parameters of the engine control unit were investigated in the engine start-up process. Ultimately, the results showed that the engine's pulsating torque was the main reason for system jerk and vibration during the engine start-up process, and the excessive intake manifold pressure before the engine's ignition was one of the main reasons for the large output torque ripple. When initiating the electric engine starting process, the jerk and vibration presented a wide fluctuation. The maximum value of the equivalent jerk was 92.12 m/s3, and the maximum value of the absolute value of the vibration acceleration was 4.077 m/s2. [ABSTRACT FROM AUTHOR]

Experimental research is essential in the development of a hybrid electric vehicle. In this study, a bench test was conducted for a compound power-split hybrid electric vehicle (PSHEV) to analyze the real dynamic characteristics of its components and the factors of system shock and vibration during the engine start-up process. Firstly, the mode switching process with an engine start-up was divided into four stages by the lever method. The basic control strategy of mode switching with engine start-up was formulated and tested on a bench test platform. Secondly, based on the bench test data, the output characteristics of the battery motor, engine, and driveshaft were analyzed in detail. The main variable parameters of the engine control unit were investigated in the engine start-up process. Ultimately, the results showed that the engine’s pulsating torque was the main reason for system jerk and vibration during the engine start-up process, and the excessive intake manifold pressure before the engine’s ignition was one of the main reasons for the large output torque ripple. When initiating the electric engine starting process, the jerk and vibration presented a wide fluctuation. The maximum value of the equivalent jerk was 92.12 m/s3, and the maximum value of the absolute value of the vibration acceleration was 4.077 m/s2.

An original ultracapacitor (UC) based compact electric power source is introduced in the paper.The device employs the synergy between rich energy content of vehicle lead-acid batteries and power capabilities of UCs to allow emergency starting of internal combustion engine in case of a weak battery. The UC-based power source is capable of charging at low rate from the battery and then providing current burst required for proper engine starting. A prototype is designed employing original power circuitry, and a dedicated algorithm for optimal UC charging is developed. The device is successfully used for diesel engine starting, as shown by experimental results. [ABSTRACT FROM AUTHOR]

Abstract: The starting is a special transient process of engine operation, which is included in the New European Driving Cycle of light duty vehicles (NEDC). This is a critical operation mode of diesel engines with respect to pollutant emissions and to stability of the combustion process. In this work, a turbocharged, direct injection (DI), diesel engine equipped with common rail injection system and EGR strategy was tested during the starting. The engine was tested at relatively cold and warm start. Pollutant emissions (HC, NOx, smoke opacity and particle size distributions), in-cylinder pressure and operating parameters such as rotation speed, relative fuel–air ratio and EGR valve position were registered during the tests. The engine was fueled with a pure low sulfur diesel fuel, and blended with ethanol and butanol. Fuel blends were prepared with the same oxygen content (~3.3% in mass). The results show that alcohol diesel blends lead to a positive effect on the reduction in the smoke opacity and particle concentration during warm engine start with similar nitrogen oxide (NOx) emissions. At cold start, blends tested produced combustion instabilities. This fact, jointly with inefficient operation of the diesel oxidation catalyst, produced an increase of all regulated pollutant emissions. [Copyright &y& Elsevier]

• A novel single-motor power-reflux hybrid transmission system is proposed. • The characteristics are analyzed based on dynamic model of hybrid powertrain. • The work law of driving and speed regulating mode switches is formulated. • Comprehensive multilevel coordination control strategy is proposed at engine start. • Simulation results show engine starting jerk effectively is reduced by 65.88%. In this study, a novel single-motor hybrid electric vehicle (HEV) equipped with a power-reflux coupling transmission system is proposed for improving the fuel economy of HEVs. The structural characteristics and operating principles of the proposed HEV were analyzed, and a detailed driveline dynamic model was established. Then, a rule-based energy management strategy regulated by the optimal comprehensive energy economy was adopted to divide its working mode regions. As a result, the engine starting process in vehicle motion may involve not only a driving mode switch but also a speed regulation mode conversion, resulting in noticeable jerks and an unpleasant driving sensation. To address this problem, this study presents a multilevel torque coordination method that synergizes the transient intervention of torques from two power sources and clutches and changes the transmission ratio. Compared with the simulation results of the dynamic performance of a vehicle under conventional control strategy, the results of the proposed control strategy demonstrate a better control effect, which can ensure the smoothness of power transmission during engine startup to effectively minimize the impact on the system and improve the ride comfort. [ABSTRACT FROM AUTHOR]