“Tough Gear”and “High Quality”for New X-TRAIL - 2. “VC-TURBO”and“e-POWER”System5.2 Acceleration performance and drivabilityFig. 9 Acceleration G at standing start5.2.1 Acceleration performance5.2.2 Drive torque control matched to supercharged engine characteristics5.2.3 Improved feeling of acceleration due to engine 14Fig. 10 Time chart of driving torquesoundThe high driving power provided by the new motor of the newly developed e-POWER system and the high-output power generated by the VC-TURBO engine enable the car to achieve the top-level acceleration performance in its class.Fig. 9 shows a comparison of acceleration G and vehicle speed profiles during the start acceleration with the conventional HEV system. The acceleration G is quickly launched immediately after starting acceleration by exploiting the 100% motor drive characteristics, which helps realize the high response. In addition, the high G is maintained to produce a feeling of acceleration growth even after the rise in acceleration G.A supercharged engine is accompanied by a delay in the supercharging response when the torque increases compared to that for the naturally aspirated engine. Given this characteristic, the newly developed e-POWER system incorporates a new technology that controls the drive torque to ensure smooth acceleration while generating supercharging pressure.Fig. 10 shows the relationship between the supplied energy and torque during acceleration. The battery energy is used immediately after acceleration to generate driving torque with a good response. Meanwhile, the engine is started, and then, the energy generated by the engine is added to the energy of the battery to increase the driving torque.the generated drive The supply of the energy generated by the engine at this time is delayed because of the delay in the supercharging response. However, the drive torque is controlled to ensure a smooth increase without temporary drops attributed to this delay (a). The driving force is changed based on the acceleration request of the driver because it is possible to supply the generated energy after the engine is supercharged (b). Thus, a large acceleration is achieved compared to that of a naturally aspirated engine, whereas a smooth and boosted supercharging pressure is generated without the uncomfortable feeling produced when the accelerator is operated.We developed a technology that provides a pleasant feeling of acceleration from the sound of the engine during power generation to allow the driver to feel the acceleration not only from the acceleration G but also from the sound of the engine.The e-POWER system can control the engine and wheel axle drive systems independently, which allows the engine speed during acceleration to be set freely. In addition, the VC-TURBO engine can generate sufficient engine torque even in the low revolution range. Utilizing these two features, the e-POWER system enables the engine speed to not only increase immediately, but also to increase in conjunction with the vehicle speed even if the driver strongly requests acceleration the accelerator pedal is depressed considerably).The relationship between the engine sound (rpm) and the driver's acceleration request is defined to set the engine speed linked to the vehicle speed for the following two zones through sensory evaluation.Zone 1, where the engine sound (rpm) is high relative to the vehicle speed.Zone 2, where the vehicle speed and engine sound (rpm) are synchronized.Fig. 11 shows both zones 1 and 2. In Zone 1, the engine sound (rpm) rises before the vehicle speed, which creates a sense of discomfort during acceleration. In Zone 2, the vehicle speed and engine sound (rpm) rise in tandem, which generate a comfortable feeling of acceleration that matches the acceleration request. If the driver's request for acceleration is stronger, Zone 2 can be used.(when
元のページ ../index.html#19