*4.1. HEV Baseline Model with Rule-Based Control Strategy*

The rule-based control was applied on the baseline HEV model. With the urban and highway driving simulation, fuel economies were 47 MPG (miles per gallon) and 39 MPG, and composite fuel economy was 43 MPG. The simulation results and the manufacture official data are shown in Table 3. The differences of urban, highway, and composite fuel economy were −2.1%, 5.4%, and 1.6%, respectively, which were acceptable. The simulation model can be used to represent the original vehicle. With this rule-based control model as the baseline, the average efficiency of MG1 and MG2 were

monitored as well. The urban and highway efficiency values of MG1 were 0.83 and 0.85, respectively, and those of MG2 were 0.85 and 0.84, as shown in Table 4.

**Table 3.** Comparison of fuel consumption between rule-based control model (RB) and factory data.



