Text/Car Bright
Photo/From official
As a new route of hybrid technology, Xuanyi e-POWER was listed (the whole series is priced at 138,900-17.49 million yuan) and announced that it has opened a new journey in the field of domestic hybridization. This set of e-POWER technology, compared with Toyota's THS, Honda's i-MMD, and by-BYD's DM-i, Kunpeng DHT, Changan Blue Whale iDD and other autonomous plug-in hybrid technology, what is the difference between e-POWER technology? How do we position it within the entire hybrid system? Is it leading or behind? Why did Nissan choose this seemingly conservative technical route? Let's talk about it in this article.
e-POWER is seen as an extender technical route, or more precisely, an unplugged extender hybrid. It is also because it cannot be plugged in, the 1.5-degree battery configured by Xuanyi e-POWER can support driving for about 5 kilometers in pure EV mode, so it cannot enjoy the benefits of domestic tax exemption and green card (the domestic policy is to support at least 50 kilometers of pure electric endurance to get a green card). This makes e-POWER's sales competitiveness less competitive.
In addition, e-POWER is a "simple" tandem structure, the mechanical force of the engine, through the generator is first converted into electrical energy, input to the battery, the battery's power is transmitted to the power motor through the inverter, and then to the wheel. The whole process is a "mechanical force-electricity-mechanical force" secondary transformation process. To be precise, it is a completely oil-burning electric car. In the eyes of some, the secondary conversion involves more energy loss, isn't that redundant?
Why not add a battery?
Compared with the ideal ONE and the M5, which are also part of the range extender, they are equipped with a battery of about 40 degrees, which can support pure electric endurance of more than 100 kilometers, and can also hang a green card. In addition, plug-in hybrid technologies such as BYD DM-i and Blue Whale iDD, which are born from honda i-MMD structures, can also get green cards because of charging interfaces and large battery capacity.
It is said that e-POWER in the existing tandem structure, adding a large battery to mix a green card should be technically no difficulty. So why not do it?
The reasons I analyzed are: First, large batteries need to add hundreds of kilograms of weight, contrary to the goal of fuel saving. The Xuanyi e-POWER weighs less than 1.5 tons, just over a hundred kilograms more than the fuel version. Ideal ONE was initially exposed to 10 oils per 100 kilometers and its excessively heavy maintenance mass was inseparable (weighing 2.3 tons, at least more than 300 kilograms heavier than the average medium and large SUV).
Second, the e-POWER complete set of powertrains is characterized by miniaturization and high integration, making it suitable for a wider range from small cars to large cars. The e-POWER was introduced on a small car like the LEAF. Domestic Xuanyi is equipped with the latest second-generation e-POWER hybrid system, compared with the first generation of technology, the biggest change is higher integration, the engine, motor, motor, inverter is highly integrated, the volume is reduced by 40%, the weight is reduced by 33%, and the use of better performance of silicon carbide (SiC), gallium nitride (GaN) and other semiconductor materials, energy transmission efficiency has also been improved. If e-POWER is to be installed on a B-class car like Tianlai one day, you can change a higher power motor and increase the battery capacity appropriately, or simply add a large battery and charging interface like toyota dual engine e+. But now Nissan is obviously looking for stability, so let's start with an A-class car like Xuanyi.
The third reason is that safety comes first. LEAF has sold more than 500,000 vehicles worldwide, with a cumulative mileage of more than 19 billion kilometers, without a single case of spontaneous combustion and major accidents. I'm afraid that no car with a big battery can guarantee this with a chest pat. After all, battery management technology is still far from foolproof, and Nissan is often introduced to the market after the technology is very mature.
The fourth reason is that for an A-class car like Xuanyi, the power of the existing e-POWER is enough. Compared with the Corolla Twin Engine and honda Lingpai hybrid, the Corolla hybrid system output is 122 horses, the Lingpai Rui hybrid is 154 horses, and the Xuanyi e-POWER is 136 horses, which is in the middle level. But the other two will automatically become the engine direct drive at medium and high speed, and Xuanyi is fully electric drive and the motor torque is as high as 300 Nm, plus the motor has the characteristics of instantaneous torque and power amplification, so in the acceleration performance and the more powerful Lingpai is comparable, the measured zero hundred is more than 8 seconds, and the Corolla due to the earlier engine intervention, the performance in the middle and rear of the acceleration is very weak, the actual zero hundred in more than 11 seconds.
Therefore, since e-POWER can meet all the goals of safety, power, fuel saving, and miniaturization, from the perspective of technology development, there is really no need to install more large batteries for a green card. To some extent, more than half of the large batteries installed on the car are the product of domestic policy orientation, and it is clear that Nissan is not willing to make such a compromise.
What's the difference when it comes up?
The entire hybrid market can be divided into three genres. Toyota's THS is a school of its own, through the planetary gears to divert power and then fuse, the structure is more complex, the advantage is fuel saving, the disadvantage is power. Toyota Dual Engine is at the bottom of the race at any level compared to the hybrids (except for the Dual Engine e+).
Honda's i-MMD is a faction, and the P2's parallel structure allows mechanical forces and electricity to be disconnected and coupled by clutching. The autonomous plug-in hybrid can basically be regarded as a derivative of the similar structure of i-MMD, and a charging interface and a large battery are added on the basis of i-MMD, which supports pure electric endurance plus green card.
The concatenation structure of e-POWER is the third genre. Both the ideal ONE and the M5 can be seen as connected in series structures, with additional charging interfaces and large batteries. It is characterized by a relatively simple configuration, full-time electric drive, and the engine only acts as a range extender and does not participate in direct output.
Therefore, compared with the first two genres, the biggest feature of e-POWER is that the engine always hides behind the scenes, does not need direct drive, and always keeps the engine under the best working conditions of low load and low fuel consumption through the energy management system. It's as if your boss only hides behind the scenes to direct, and doesn't have to work overtime like you, so it's good to look good, mentally and physically.
So what is the difference between Xuanyi and Lingpai hybrid and Corolla twin engines equipped with e-POWER? In addition to the power difference, the biggest difference is that the noise performance is better, lingpai and corolla hybrid models due to rapid acceleration when the engine will intervene, engine noise mixed with motor sound, will be mixed into a more abrupt "whining" sound. I feel this all too well when driving higher-caliber hybrids such as the Ince and the New Highlander. The noise, acceleration and deceleration of Xuanyi driving are very close to electric vehicles, especially when driving on the highway, it is quieter than those two. Although it is equipped with a 1.2L three-cylinder engine, which may sound like it may have "jitter potential", the engine will be quickly dragged by the motor to more than 2000 rpm at start-up, avoiding the low-speed range that is prone to jitter, thus ensuring good NVH performance.
The future of e-POWER
Why does e-POWER achieve secondary transformation of "mechanical force - electricity - mechanical force"? It is to make the motor and engine run in the most efficient working conditions, so that both are kept in the most comfortable state. Compared with the engine in the hybrid system of the two fields, the engine of e-POWER is hidden behind the scenes the whole time, and only one thing needs to be done is to power the power supply. Therefore, it does not need to face the complex road conditions, so the thermal efficiency of the engine is easier to improve, and the room for improvement is also larger.
So the next step of e-POWER technology optimization is first of all to improve the thermal efficiency of the engine, e-POWER hybrid engine is based on the STARC concept of development, through high compression ratio, high rolling current, thermal energy management and the engine operation in a narrow charging zone and other means, the current Xuanyi on the 1.2L engine is only the entry level of e-POWER, its thermal efficiency has reached 43%. The next step is Nissan's goal is 50% thermal efficiency.
Qashqai in overseas markets is already equipped with 1.5T e-POWER, its 1.5T engine is a variable compression ratio engine, its engine maximum power is 158 hp, and the system has a comprehensive output of 189 hp. The 50% thermal efficiency target is likely to fall on the future 1.5T e-POWER.
Some people say that under the best working conditions of this engine on the highway, it is a waste to let the engine hide behind the scenes. But on the other hand, if the engine is thermally efficient enough, is it necessary to stand up on the highway and "drive directly"? If you want to meet the goal of power, isn't it easier to change to a larger motor?
In addition, the small size and high degree of integration not only mean that it can be adapted to small cars, but also leaves room for equipping large motors and large batteries. Larger cars can be equipped with large motors to achieve a balance between performance and fuel consumption. If the time is ripe, it is not excluded that Dongfeng Nissan will install a charging interface and a large battery.
Driving value view
e-POWER, in my opinion, is a conservative "compromise" technical route. The starting point of this conservatism is security, stability and maturity. Why is it eclectic? Because its fuel consumption is lower than that of the same level of fuel vehicles, NEDC 100 km 3.9L, power in the fuel A class car is also considered "small steel cannon", the actual zero hundred and eight seconds more, power and fuel consumption at the same time. Compared with pure trams, there is no charging and spontaneous combustion anxiety, but there is no pure tram because of the blessing of large motors and large batteries, which is accelerated by five or six seconds. Compared with PHEV, there is less pure electric endurance and green card advantages, but compared with most PHEV", "there is electricity is a dragon, no electricity is a worm", its fuel consumption is more guaranteed. In addition, the configuration is simple, the degree of integration is high, it can be installed in small cars such as LEAF and NOTE, and the adaptation model is more extensive, and the simple configuration means that the failure rate is low and stable. LEAF's performance has proven it.
Therefore, it can be said to be a compromise "bucket type" technology, the advantages of various technical routes are a little, and no single item can stabilize the other technical routes, but it is comprehensive.
In the transition period from fuel vehicles to new energy, Nissan once again raised the banner of "Technology Nissan" through e-POWER, and the significant reduction of fuel consumption has also made a practical contribution to energy conservation and emission reduction. Although it does not have the basis of word of mouth like the two-field hybrid because of its late entry into China, objectively speaking, it is a scheme with the fewest hidden dangers and shortcomings under the constraints of various realistic conditions. Stable, reliable and safe is the first demand of the people's cars. Isn't it?