The Euro VII emission standard is a perfect interpretation of what it means to lift high and fall gently. The most stringent in the history of the once sworn will give birth to dual three-way catalysts, as well as larger-size GPFs and other exhaust pipe science landing. At present, most of the various particulate matter and greenhouse gas emission scales have shrunk back to the level of the last Euro VI. However, since Euro VII retains restrictions on tire wear and brake particulate matter emissions, it is still considered the "strictest emission standard in history" from an innovative point of view. The signboard is there, and the car company bigwigs have also been appeased, is this a celebration of the whole world?
The strongest internal combustion engine, landed with Euro VII
As mentioned earlier, in terms of core internal combustion engine emissions, Euro Seven did not rush forward this wave. As a result, the Euro VII emission standard will most likely be officially implemented in July next year. After all, nominally, the sword of Damocles of "banning burning in 2035" still hangs. If Euro 7 fails to land in the repeated see-saw, the window between its implementation time and the so-called ban schedule will be too short. In short, in theory, Euro VII left at least one generation for the internal combustion engine. However, in the absence of a substantial large-scale upgrade of the new emission standards, will car companies choose to put on a bad basis in order to maximize profits in the last ten years?
I'm afraid the answer is no, this is not to say that the car companies that have been around for a hundred years are online. Rather, emissions regulations still have a role. In the case of Euro VII, for example, although the vast majority of the standards deal with particulate matter emissions, they are no different from the current Euro VI standards. But in terms of carbon monoxide emission standards, it is directly cut in half. In terms of how the internal combustion engine works, the only way to limit carbon monoxide is to solve the problem of how well it is combusted. GPF basically only affects particulate matter, and although the three-way catalyst includes the work of converting carbon monoxide, the one-time halving may not be as convenient as upgrading the engine from a technical point of view.
Because of the upgraded Euro VII emission standard, the carbon monoxide part has been on par with China VI B. Considering that global car companies, including Volkswagen and Toyota, have all made mistakes in the exhaust pipe problem when switching to China VIB. After Euro 7 is basically finalized, it is a sure thing that the next generation of internal combustion engines will pursue higher combustion efficiency. However, due to the emission requirements of particulate matter and nitrogen oxides in China VIB, they are more stringent than those in Euro VII. Therefore, at least in the national version, it is still necessary to put more effort into the exhaust pipe science such as GPF and three-way catalyst.
Back to the technical topics that Euro VII and China VIB need to face together. If you want to make the combustion of the internal combustion engine more sufficient, it can be basically divided into two directions: charged and uncharged. From the point of view of uncharged, higher injection pressure, variable geometry turbines, and fuel stratification combustion are among the technical representatives. Among them, the first two are basically named after the fifth-generation Volkswagen EA888. Judging by what has been revealed so far, the new engine is expected to use 500 bar of high-pressure direct injection, as well as VTG variable geometry turbo technology. As for the layered combustion of fuel oil, it is said in another way, that is, lean combustion or pre-combustion. Unlike high-pressure direct injection and VTG, regardless of the stratified combustion technology, there are relatively few applications in the market. For example, Maserati's Poseidon engine, Mazda's compression-ignition engine, and so on. The reason for this phenomenon may be that the mechanical level is involved to this point, so it is better to use electricity directly?
It's not that the engine is replaced directly with an electric motor, but that more electrified equipment is used in the internal combustion engine to improve efficiency. For example, all the mechanical structures of the internal combustion engine are changed to electronic control, such as electronically controlled oil pumps, electric turbines, electronic valve infinitely variable adjustment, and so on. Mercedes-Benz and Audi are leading brands in the application of internal combustion engines with the above electronic control technology. Compared with various mechanical optimizations, purer electronic control components can more precisely adjust the breathing of the internal combustion engine and save mechanical energy loss. However, to do this, more demanding calculations are required. and a higher level of modular manufacturing to dilute the high cost of components. Finally, the vehicle itself must be electrified. At least it needs to meet the standard of 48V mild hybrid to afford so many electronic control equipment.
After Euro VII, there will be no pure fuel cheap cars?
The evolution of the internal combustion engine mentioned above, without exception, requires additional cost support. Even with the popularity of modular engines, even if the cost can be further diluted by a wider audience. However, for more low-cost models, or to be clear, ordinary A-class and lower positioning models, or in terms of displacement, that is, within 2.0L, it is difficult to enjoy this technical iteration. Take Volkswagen's fifth-generation EA888 engine and the EA211 1.5T engine that has landed as an example. The latter's direct fuel injection pressure may eventually be locked at 350 Bar. And this is only equivalent to the level of the third-generation EA888 in the mature stage.
Even so, Volkswagen's new 1.5T engine still needs to be filled with at least No. 95 gasoline in China. This is the epitome of the paradox between advanced technology and the market. More decentralization of technology will lead to greater economic pressure on users on both the purchase and use ends. The VTG turbine, compatible with the Miller cycle, is a manifestation of the entanglement between economy and practicality. But if the emission standards go one step further, where can the small-displacement economy engine go? Obviously, if it can no longer carry more technical investment, it will have to compromise in the direction of higher efficiency. And the extreme in this direction is the range extender.
Coming back to the technical level, while the internal combustion engine becomes more efficient, its low-torque capacity will inevitably become more stretched. Electric motors will undoubtedly fill this space, but the question is, with what identity? If the internal combustion engine still wants to dominate the ratio of oil to electricity, then 48V mild hybrid and HEV will become the mainstream options. In fact, Volkswagen, mentioned many times before, has a large-scale plan to launch 48V mild hybrid products in the so-called last generation of fuel vehicle products.
But why is the 48V mild hybrid, which is already very common in Mercedes-Benz, BMW, and even the Audi brand of the Volkswagen Group, relatively slow to advance in the Volkswagen brand? The answer may lie in the dominance of the internal combustion engine, but it may not be able to pick up the girder. Specifically, the 48V mild hybrid system completely retains the internal combustion engine and transmission structure, and the electrification structure is completely new, which means that the cost increases. On this basis, car companies are more willing to see the displacement of A-class cars that were originally burdened, and can provoke the heavy responsibility of driving B-class cars, or reduce the original displacement.
The output of the motor in a 48V mild hybrid system is limited in terms of capacity and durability. As a result, the ratio of oil to electricity is easily unbalanced. The more conservative solution is to either increase the battery capacity and make it a P2 structure plug-in hybrid, which "indefinitely delays" the arrival of the critical point through a large battery. Either the power of the internal combustion engine is maintained or even increased so that its performance is sufficient to cover the entire hybrid system. The latter's masterpiece is Toyota's 2.4T hybrid, high-horsepower internal combustion engine with small battery P2 architecture, which is also enough to open up the brain.
But this kind of performance redundancy is clearly not suitable for economical products. In the case that Japanese brands basically have generalized hybrid technology with power splitting, series-parallel, and series structure without gearbox. If European car companies don't choose to be like American cars, they choose to join if they can't beat it. On the basis of the P2 architecture, we can only hope that on the one hand, by retaining the technical advantages of the mechanical gearbox, we can reduce the dependence on the power of the motor, and on the other hand, we can hope that the mass production of the system can dilute the overall manufacturing cost.
If we adhere to the perspective of long-termism, this kind of technical thinking of European car companies will eventually develop in the direction of PHEV or even REEV in terms of small-displacement engines. However, the development of PHEVs is another option that requires local policy support. At least for the time being, Europeans are more likely to choose EVs and HEVs when it comes to electrification. As for REEV, it is even more difficult, and it seems that it is no longer a technical problem to make the internal combustion engine bow its head and play assist. Rather than jumping back and forth against their ancestors, they seem to prefer to look forward to the eventual landing of synthetic fuels. If the problem of "what to burn" can be solved, the identity of the small displacement engine as a drive unit can of course still be extended. But how much synthetic fuels can cover a market outside of Europe is another question.