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Developed control algorithm for series hybrid electric power train is presented systematically, which keeps engine operation points on the locus of highest efficiency torque/speed points using a lookup table defined by engine power and speed. The off-line simulation model of series hybrid power train is developed which includes sub-models of control system and controlled objective (such as engine, motor, battery pack and so on). The debug and validation of control algorithm is performed on developed modular test facility. The results show that developed control algorithm can effectively keep engine operating on the locus of high efficiency points and much more fuel economy can be achieved than that of conventional ICE power train, meanwhile battery SOC can be maintained within reasonable level without charging outside during cycles.

Three thermo-wires with amplifying circuits have been developed to measure the time-resolved concentration of the exhaust gas recirculated into the intake manifold by a rotary valve-based exhaust gas recirculation (EGR) system of a diesel engine. Good agreement was found between the EGR rates measured by the temperature based system and a conventional CO2 tracing system. The developed EGR measuring system was used to investigate the EGR transient response in a turbo-charged and after-cooled diesel engine with a real-time measure and control system. The EGR response under EGR valve step change and engine transient operating conditions are discussed. At first, the engine was running under a certain steady condition with zero recirculated exhaust gas, then the rotary valve opened to maximum within 0.1s to demonstrate the EGR step change behavior. EGR rate and air intake stabilized in 0.5s.

A novel non-destroy repeatable-use impact theory based total cylinder sampling system has been established. This system is mainly composed of a knocking body and a sampling valve. The knocking body impacts the sampling valve with certain velocity resulting in huge force to open the sampling valve and most of the in-cylinder gas has been dumped to one sampling bag for after-treatment. The feasibility and sampling response characteristics of this impact theory based total cylinder sampling system were investigated by engine bench testing. Within 0 to 35°CA ATDC (Crank Angle After Top Dead Center) sample timing 50 percent to 80 percent of in-cylinder mass would be sampled, which was a little less compared with the traditional system. The half decay period of pressure drop was 10 to 20 degrees crank angle within 0 to 60°CA ATDC sample timing, which was about 2-3 times of the traditional system.

The incomplete combustion and misfire of diesel engine during starting result in unwanted white smoke. The histories of combustion and emission in different phases under different start conditions were studied in this paper. The optimization of the fuel injection control strategy under start conditions was performed. When the diesel engine is started under low temperature, the control strategy adapted to start the engine with a certain constant fuel mass injected per cycle, there may be misfire cycles in the initial period or in the transitional process, which is mainly caused by the mismatch between the fuel mass injected per cycle and the instantaneous engine speed. Therefore, an optimized control strategy was put forward, namely, the engine starts with high fuel mass injection in the first several cycles and then decreases step by step during the transitional period until it operates at idle condition. This strategy was validated to decrease significantly the misfire cycles.

In order to improve the vehicle economy of electric vehicles, this paper first analyzes the energy-saving mechanism of electric vehicles. Taking the energy consumption of the deceleration process as a starting point, this paper deeply analyzes the energy consumption of the deceleration process under several different control modes by the test data, so as to obtain two principles that should be followed in energy-saving control strategy. Then, an intelligent deceleration energy-saving control strategy by getting the forward vehicle information is developed. The overall architecture of the control strategy consists of three parts: information processing, target calculation and torque control. The first part is mainly to obtain the forward vehicle information from the perception systems, and the user's habits information from big data, and this information is processed for the next part.

In concept design and prototype development of hybrid power train with ISG (Integration of Starter and Generator) for transit bus one of the main concerns is to determine the appropriate parameters of power train components. Utilizing the developed off-line simulation model of hybrid power train with ISG the study on the influence of components' parameters on acceleration performance and fuel economy of transit bus is completed. Based on these the guideline strategies of parametric design of parallel hybrid power train for transit bus are brought forward in this paper. Given the condition of propulsion requirement the parametric design for this transit bus is performed targeting minimizing fuel consumption. It is conclusion that the appropriate components' parameters determined by means of parametric design can make hybrid transit bus with ISG achieve much better acceleration performance and much lower fuel equivalent consumption than that of baseline transit bus.

In concept design and prototype development of parallel hybrid power train for transit bus one of the main concerns is to determine the appropriate parameters of power train components. Utilizing the developed off-line simulation model of parallel hybrid power train the study on the influence of components' parameters on acceleration performance and fuel economy of transit bus is completed. Based on these the guideline strategies of parametric design of parallel hybrid power train for transit bus are brought forward in this paper. Given the condition of propulsion requirement the parametric design for this transit bus are performed targeting minimizing fuel consumption. It is conclusion that the appropriate components' parameters determined by means of parametric design can make parallel hybrid transit bus achieve much better acceleration performance and much lower fuel equivalent consumption than that of baseline transit bus.

Utilizing the developed off-line simulation model of series hybrid power train the study on the influence of components' parameters on acceleration performance and fuel economy of transit bus is completed. Based on these the guideline strategies of parametric design of series hybrid power train for transit bus are brought forward in this paper. Given the condition of propulsion requirement the parametric design for this transit bus are performed targeting minimizing fuel consumption. It is conclusion that the appropriate components' parameters determined by means of parametric design can make series hybrid transit bus achieve much better acceleration performance and much lower fuel equivalent consumption than that of baseline transit bus.

Utilizing the developed off-line simulation model of series power train for fuel cell transit bus, the study on the influence of components' parameters on acceleration performance and fuel economy of transit bus is completed. Based on these the guideline strategies of parametric design of series power train for fuel cell transit bus are brought forward in this paper. Given the condition of propulsion requirement the parametric design for this transit bus is performed targeting minimizing fuel consumption. It is conclusion that the appropriate components' parameters determined by means of parametric design can make fuel cell transit bus achieve much better acceleration performance and much lower fuel equivalent consumption than that of baseline transit bus.

Developed control algorithm of series power train for fuel cell transit bus is presented systematically, which keeps fuel cell pack's operation points on the locus of highest efficiency. The off-line simulation model of series power train for fuel cell transit bus is developed which includes sub-models of control system and controlled objective (such as fuel cell pack, motor, battery pack and so on). The debug and validation of control algorithm is performed on developed modular test facility. The results show that developed control algorithm can effectively keep fuel cell pack's operating on the locus of high efficiency points and much more fuel economy can be achieved than that of conventional ICE power train, meanwhile battery SOC can be maintained within reasonable level without charging outside during cycles.