Some time ago, BYD officially launched the latest generation of plug-in hybrid platform DM-i platform, and also released three new cars using DM-i technology, Qin Plus DM-i, Song Plus DM-i and Tang DM-i. We also briefly tested the new Song Plus DM-i at BYD headquarters. After that test drive video was broadcast, everyone is very interested in BYD's new DM-i technology platform. Today we will briefly analyze this new product that BYD has been working hard to create.
The completely different "electric oil hybrid"
is different from the hybrid system that mainly uses engines and motors to assist in driving. In strict sense, BYD's DM-i technology should be called an extended-range electric vehicle system with mechanical driving capabilities. In terms of mechanical structure, this DM-i hybrid system does not have the transmission in the traditional concept. Its driving core is a driving system composed of two electric motors and a very compact single-speed driving unit. Will there be any pauses in
DM-i?
Traditional hybrid systems, including BYD's current DM3.0 technology, are used to drive the vehicle in most operating conditions. However, in this new DM-i hybrid system, the vehicle is driven by the traction motor in most operating conditions. Only in two situations will the engine enter the working state: one is the high-speed stage, after the motor speed is too high and after entering the non-economic range, the engine directly drives the vehicle through the direct connection mechanism; the other is the gas-electric parallel drive situation when the firepower is fully turned on in the emergency acceleration conditions.
In other words, the new BYD car with the DM-i architecture is an electric car in most cases, and it relies on motor drives, so the problem of shifting and shifting that everyone is most worried about does not exist - it has no gears at all, so how can there be shifting and shifting? Also because a set of mechanical direct connection mechanisms are retained, everyone is also concerned about whether BYD's DM-i system will have a stutter at the moment when the engine is involved in driving. The answer is no.
Why is it called a "dual motor" hybrid system?
Why is the DM-i hybrid system to put it bluntly, it is clearly the engine that drives one generator to generate electricity, and then uses electric power to drive another motor to pull the vehicle, but it is called a dual-motor hybrid system? Because the identity of the generator directly connected to the engine can be changed very quickly. In most cases, the small motor on the DM-i hybrid system is used to generate electricity, but it also functions to start the engine and coordinate the engine speed. When the hybrid control unit sends the engine into the working state and connects the wheels, the generator can instantly "twist" the engine's speed to a speed that is consistent with the gear structure. Everyone knows that if there is a speed difference, it will cause a jerk, but the DM-i system does not have a jerk when the engine enters work under the adjustment of the motor, so there will naturally be no jerk. The new architecture of
, the new challenge to the engine, the
DM-i architecture also poses a new challenge for BYD, that is, the seemingly beautiful dual-motor hybrid system requires an additional energy conversion process, and the efficiency of the engine must be very high, otherwise everything will be a silhouette. BYD's solution is very clever. The hybrid dedicated 1.5-liter self-priming engine they built is actually not a new technology with very difficult and very high technical requirements. BYD focuses all its energy on "optimization".
First of all, there is no attachment on this engine to waste the power of the engine. Common oil pumps, water pumps, air conditioning compressors are all replaced by electric ones. Secondly, BYD diverted the cooling of the cylinder and cylinder head on the cooling system, without wasting heat; then, it effectively reduces the operating resistance inside the engine, and the thermal efficiency of more than 43% is actually a little bit unremarkable improvement.
. For hybrid platforms like DM-i, where most engines are power generation, the ultra-high thermal efficiency has greater practical significance, because the engine working range is actually very narrow. BYD only needs to concentrate on doing this small section of fuel economy. Unlike traditional fuel vehicles or hybrids, it has to take into account the performance of pulling from idle to the red line, and it also has to work hard to expand the engine efficiency dessert area.
BYD’s exclusive "virtuous cycle"
has been discovered? This has become a virtuous cycle for BYD DM-i. Dual-motor hybridization allows the engine to only take into account few working conditions. Few working conditions allow BYD to concentrate on improving the thermal efficiency of the engine specified working conditions, which can reduce development difficulty and cost. This specially developed engine can greatly reduce the fuel consumption of the DM-i hybrid system, with low input and high output. Everyone knows BYD, a car company, that you have to produce everything yourself, and that battery electronically controlled motors and even many parts in the car are done by themselves, which also makes their cost control perform very well. The new Qin Plus DM-i price starts at more than 100,000 yuan, which is an example. No wonder BYD dares to shout the slogan "challenge fuel vehicles".
The new DM-i hybrid system is far more than that. When BYD's engineers introduced us, they revealed several subsequent R&D directions - the DM-i hybrid system will be further combined with the rear axle motor to form a four-wheel drive version, and a higher power DM-i hybrid module is also under development. BYD is even seriously considering matching the DM-i system with a larger capacity battery pack... What new toys will BYD bring out to make everyone's eyes shine? Let's wait and see.
