Given that energy conservation and environmental protection are two important goals for the automotive industry, the application of a hybrid electric powertrain can improve vehicle energy efficiency while decreasing f...Given that energy conservation and environmental protection are two important goals for the automotive industry, the application of a hybrid electric powertrain can improve vehicle energy efficiency while decreasing fuel consumption and engine emissions. Planetary gear-based power-split hybrid powertrains have become widely used in passenger vehicles, but remain rarely employed on transit buses. This study proposes a novel hybrid powertrain based on two planetary gear sets(CHS) and presents its operating principles along with development of a control strategy for the powertrain. The CHS hybrid powertrain operates in electric mode when the driving power demand is low, and changes to a hybrid electric mode according to the power-split principle of the planetary gear set. To validate the feasibility of the designed CHS hybrid powertrain, a prototype transit bus equipped with the designed hybrid powertrain system was built, and the operating characteristics of the system were analyzed through a performance test conducted on a chassis dynamometer. Compared with a conventional powertrain, the CHS hybrid powertrain can reduce fuel consumption by 39%. Thus, the CHS hybrid powertrain is a good solution for heavy-duty applications such as hybrid transit buses because of its simple structure and excellent fuel efficiency.展开更多
Two new coordination complexes[Cd(L)2(1,2,3-HBTC)]·3H2O(1)and{[Zn(L)(1,2-BDC)]-H2O}n(2)were synthesized under hydrothermal conditions(1,2,3-H3 BTC=1,2,3-tricarboxybenzene,1,2-H2 BDC=1,2-dicarboxybenzene and L=2,2...Two new coordination complexes[Cd(L)2(1,2,3-HBTC)]·3H2O(1)and{[Zn(L)(1,2-BDC)]-H2O}n(2)were synthesized under hydrothermal conditions(1,2,3-H3 BTC=1,2,3-tricarboxybenzene,1,2-H2 BDC=1,2-dicarboxybenzene and L=2,2’-H2 biimidazole).1 crystallizes in monoclinic,space group P21/c with a=12.256(5),b=11.620(5),c=17.479(5)A,β=95.548(5)°,V=2477.6(16)A^3,Z=4,C21H22N8 O9 Cd,Mr=642.86,Dc=1.724 g/cm^3,F(000)=1296,μ(MoKa)=0.950 mm^-1,R=0.0546 and wR=0.1724.2 belongs to the monoclinic system,space group P21/c with a=7.408(4),b=20.743(10),c=10.194(5)A,β=95.648(6)°,V=1477.3(12)A^3,Z=4,C14H12N4 O5 Zn,Mr=381.65,Dc=1.716 g/cm3,F(000)=776,μ(MoKa)=1.698 mm^-1,R=0.0574 and wR=0.1632.The central Cd(Ⅱ)ion in 1 is coordinated with five atoms,forming a slightly distorted square-pyramidal geometry.The central Zn(Ⅱ)ion in 2 is four-coordinated by two nitrogen atoms from one L ligand and two oxygen atoms from two different 1,2-BDC anions.In addition,luminescent property of 1 has been investigated,and natural bond orbital(NBO)analysis of 2 has been calculated by the B3LYP/LANL2DZ method.展开更多
文摘Given that energy conservation and environmental protection are two important goals for the automotive industry, the application of a hybrid electric powertrain can improve vehicle energy efficiency while decreasing fuel consumption and engine emissions. Planetary gear-based power-split hybrid powertrains have become widely used in passenger vehicles, but remain rarely employed on transit buses. This study proposes a novel hybrid powertrain based on two planetary gear sets(CHS) and presents its operating principles along with development of a control strategy for the powertrain. The CHS hybrid powertrain operates in electric mode when the driving power demand is low, and changes to a hybrid electric mode according to the power-split principle of the planetary gear set. To validate the feasibility of the designed CHS hybrid powertrain, a prototype transit bus equipped with the designed hybrid powertrain system was built, and the operating characteristics of the system were analyzed through a performance test conducted on a chassis dynamometer. Compared with a conventional powertrain, the CHS hybrid powertrain can reduce fuel consumption by 39%. Thus, the CHS hybrid powertrain is a good solution for heavy-duty applications such as hybrid transit buses because of its simple structure and excellent fuel efficiency.
基金Supported by the National Natural Science Foundation of China(No.21607051)。
文摘Two new coordination complexes[Cd(L)2(1,2,3-HBTC)]·3H2O(1)and{[Zn(L)(1,2-BDC)]-H2O}n(2)were synthesized under hydrothermal conditions(1,2,3-H3 BTC=1,2,3-tricarboxybenzene,1,2-H2 BDC=1,2-dicarboxybenzene and L=2,2’-H2 biimidazole).1 crystallizes in monoclinic,space group P21/c with a=12.256(5),b=11.620(5),c=17.479(5)A,β=95.548(5)°,V=2477.6(16)A^3,Z=4,C21H22N8 O9 Cd,Mr=642.86,Dc=1.724 g/cm^3,F(000)=1296,μ(MoKa)=0.950 mm^-1,R=0.0546 and wR=0.1724.2 belongs to the monoclinic system,space group P21/c with a=7.408(4),b=20.743(10),c=10.194(5)A,β=95.648(6)°,V=1477.3(12)A^3,Z=4,C14H12N4 O5 Zn,Mr=381.65,Dc=1.716 g/cm3,F(000)=776,μ(MoKa)=1.698 mm^-1,R=0.0574 and wR=0.1632.The central Cd(Ⅱ)ion in 1 is coordinated with five atoms,forming a slightly distorted square-pyramidal geometry.The central Zn(Ⅱ)ion in 2 is four-coordinated by two nitrogen atoms from one L ligand and two oxygen atoms from two different 1,2-BDC anions.In addition,luminescent property of 1 has been investigated,and natural bond orbital(NBO)analysis of 2 has been calculated by the B3LYP/LANL2DZ method.