## 5 Results and Analysis  
By simulating the optimal dynamic performance and the optimal fuel economy for the configuration candidates, 196 configurations that satisfy the screening conditions are obtained. To further obtain the configuration with excellent comprehensive performance, Arrizo 7e is selected as the reference configuration to optimize all configurations that satisfy the screening conditions. Finally, the four Pareto optimal configurations (configuration I-IV) with better fuel economy and dynamic performance than reference configuration are obtained, as shown in Figure 11. In Pareto optimal configurations, configuration IV has the best dynamic performance with an acceleration time of 10.0642 s, and configuration I has the best fuel economy of 3.7141 L/100 km. Configuration II at the corner of Pareto front possesses the most balanced performance, which means that it has the best comprehensive performance. The acceleration time of 0-120 km/h and the fuel economy for configuration II are 10.2124 s and 3.9251 L/100 km, respectively. Four Pareto optimal configurations are shown in Figure 12, and their acceleration time, fuel economy, and operating mode are shown in Table 4.  
To further explore the characteristics of energy consumption for the optimal configuration in the proposed scheme, the configuration II with the best comprehensive performance and the reference configuration Arrizo 7e are selected for the comparative analysis of energy consumption. The performance of the reference configuration is also simulated by applying the global optimal control strategy based on DP. Compared with the reference configuration, the fuel economy and dynamic performance of configuration II are improved by 11.26% and 25.40%, respectively. Under the urban road cycle and highway cycle, the distributions of working points for power resource components and SOC curves in configuration II are shown in Figures 13 and 14. Most of the engine working points of configuration II are close to the optimal operating line (OOL), which indicates that the adjustment approach combining MG and CVT adopted in configuration II can adjust the engine speed and torque excellently, and keep the engine operate in high efficiency continuously. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Configuration** & **Fuel Economy (L/100 km)** & **Acceleration Capacity (s)** & **Operating Mode** \\ \hline I & 3.7141 & 12.3412 & 1-_spd_, _2-trq_, _1-EV_ \\ II & 3.9251 & 10.2124 & 1-_spd_, _2-trq_, _1-EV_ \\ III & 4.0350 & 10.1334 & 1-_spd_, _1-trq_, _1-EV_ \\ IV & 4.1629 & 10.0642 & 1-_spd_, _1-trq_, _1-EV_, _1-eng_ \\ Arrizo 7e & 4.4231 & 13.6895 & 1-_spd_, _1-trq_, _1-eng_ \\ \hline \hline \end{tabular} Where _spd_, _trq_, _EV_, and _eng_ represent speed coupling mode, torque coupling mode, pure electric mode, and engine-alone driving mode, respectively.  
\end{table} 
Table 4: Performance and operating mode of Pareto optimal configuration. Figure 13: Distribution of components working points in configuration II. **(a)** UDDS; **(b)** HWFET. Table 5 presents the proportion of high-efficiency region of engine working points in the two configurations (In this paper, the region with fuel consumption rate less than 270 g/kW\(\cdot\)h is defined as the high-efficiency region). Table 6 shows the average efficiency of MG in the two configurations under different test cycles. From Table 5, it can be seen that the engine operating efficiency of configuration II has been significantly improved in the urban road cycle, and the proportion of high-efficiency region has been increased by 7.75% compared with the reference configuration. In the highway cycle, due to the high operating efficiency of engine, the potential to further improve engine efficiency is limited. Therefore, the proportion of high-efficiency region of configuration II is only 0.93% higher than the reference configuration.