TU-TESL

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The soul of PHEV: will it lose power! The standard answer to this question is whether the non charging PHEV will save more fuel than the same fuel vehicle. In the mass production of hybrid vehicles, the technology platform can be divided into three levels, which are analyzed in the order of backward to advanced. The first category: PHEV dq400e p2.5, the two brands of plug-in hybrid cars that will lose power, cannot save energy without charging, because their hybrid systems are relatively poor. Taking dq400e hybrid as an example, there is only one motor in front of the mass production vehicle - the driving motor integrated in the middle of the double clutch. This motor can only realize idle charging. During driving, the vehicle power loss is mainly driven by 1.4T of ea211 platform; however, idle charging can not be fully charged. Because the combined charging power of internal combustion engine and motor is high, the vehicle group needs to reserve a small part of electric energy Slow charge. Therefore, if the dq400e system is not charged, it will cost more fuel, such as Passat and tuguan PHEV. The p2.5 structure of Geely is similar to dq400e in operation principle, because there is only a 60kW drive motor integrated with gearbox in the whole vehicle. However, this motor is special. It outputs power through the even shaft of the gearbox, which is different from the clutch structure of 400e. However, no matter what the driving system is different, the system can not be charged without BSG power generation and start-up integrated machine, and its charging mode is also idle P-gear forced charging, with the limit of soc85%. These vehicles are basically fuel vehicles after power loss, because the effect of kinetic energy recovery as a supplementary power is very general, the core of driving power generation is BSG. The second category: the entry-level PHEV universal / fac / Liangtian ECVT SAIC edu joint venture brand hybrid car is good at using ECVT hybrid gearbox, because this special gearbox integrates two motors, there is no traditional internal combustion engine gearbox, but it can take into account two operation modes of internal combustion engine - reducing the manufacturing cost is very attractive. One of the two motors is the generator, the other is the driving motor; its operation mode is the internal combustion engine series generator, the main driving mode is to generate electricity for group charging, and the vehicle is still driven by the driving motor. The thermal efficiency of the internal combustion engine is about 35%, and the energy conversion rate of the motor is more than 90%. Therefore, when the internal combustion engine is used to generate power at rated power, the fuel consumption of the electric drive is always lower than that of the direct drive of the internal combustion engine. (the operation mode is as follows) the concept of edu system is the same as ECVT, which is mainly driven by internal combustion engine power generation, and the fuel consumption is also relatively low. However, these two kinds of gearboxes have very prominent shortcomings. One is that the power of the generator motor is low, and the auxiliary output power of the internal combustion engine is still needed in the state of high power consumption such as rapid acceleration or high-speed cruise, but the internal combustion engine has only one forward gear, so the output power can only be increased by pulling high rotation (fuel consumption & noise). The second is that the transmission integrated with two motors limits the power of the driving motor, and the motor with only tens of watts can not bring good driving experience in EV mode. This is the reason why edu will take out the green hybrid DM system and imitate it. The third type: technology flow PHEV BYD dm3.0 BYD dm4.0 without power loss. At present, the new energy vehicles of BYD Dynasty series are still in the era of 3.0. The system includes: internal combustion engine (1.5T / 2.0T), BSG power generation and start-up integrated machine, independent single drive motor or front and rear double drive motor combination. The core of the system without power loss is the 25kW power BSG, which can be driven by electric motor when using the energy-saving mode in driving. The internal combustion engine will realize the reev extended range driving mode like edu / ECVT. When charging during driving, the SOC can be adjusted according to the SOC setting and the need of long-term commuting by mode active switching. In the hybrid mode of HEV, the fuel consumption without power loss will naturally be very low; moreover, after the battery capacity is reasonably controlled, the driver can switch to EV mode in the most fuel consuming congested road section, which saves frequent start and stop and high fuel consumption at idle speed. Note: the BSG motor of dm3.0 system can only meet the requirements of medium and low speed extended range driving, but it is set to generate power during driving. Secondly, the internal combustion engine of this system matches the traditional 6-gear wet double clutch gearbox, and it is a hybrid special gearbox matching the DM platform; the multi gear gearbox can give full play to the performance of the internal combustion engine, and also can reasonably control the matching of the speed and the speed to minimize the fuel consumption, which is impossible for the engine with only one forward gear edu / ECVT. Secondly, the power of independent drive motor of DM system is much higher, the power of single motor always exceeds the power of dual motor of edu / ECVT, the higher the motor power is, the slower it will enter the high power consumption state of constant power, and the comprehensive energy consumption will also be lower. Conclusion: the dm3.0 system is the lowest energy consumption in the non charging PHEV, but we need to have a certain degree of mastery of the characteristics of the system - to be able to use it, the system has a high playability and is suitable for the players, and the car is much "researched". The dm4.0 system should have two possible platforms, among which there will be a strong increase program ferroelectric version, the power generation will be very high, the pure electric operation should be 150-200 km; the next is the upgrade of the performance version of the 3.0 generation, the power experience will be better, and the energy consumption will be lower. However, the 4.0 system will not be available in the short term, because the competing products are not close to 3.0.