Analysis of Tank 300 Hybrid： The reliability of single motor is good, but how to optimize the fuel consumption of feed？
The combination of hybrid and off-road vehicles often makes off-road enthusiasts full of expectations, with low fuel consumption and high power.
At the just-concluded Chengdu Auto Show, the tank booth brought two hybrid models, the tank 300 HEV and the tank 500 PHEV. Although both cars were just unveiled, they also attracted the attention of a group of potential consumers. The combination of hybrid off-road vehicles is not new. herdsman 4xe plug-in hybrid vehicles have been launched for a long time. Although the strength is still very strong, the price is also very expensive.
Therefore, consumers still need a hybrid off-road with a lower price. Of the two cars released by the tank, the attention of the tank 300 HEV should be the higher of the two. What is the strength of the HEV system used in this tank? What are the advantages and disadvantages of putting it on the tank 300?
Why not use DHT and P2 structure?
The pure fuel vehicle market is welcoming a new era, not pure electricity, but hybrid. This is also the reason why so many car companies have started to launch hybrid products one after another. According to the previous exposure information, the 300 HEV version of the tank will use a 2.0T hybrid system matching P2 motor, using a 9HAT gearbox, with a maximum power of 224kW and a maximum torque of 640 Nm.
P2 motor structure has three layout modes:
1. Put the P2 motor on one side of the engine, and the clutch is in front of the motor and the transmission. Under this structure, the main function of the P2 motor is similar to that of the P1 motor, which can play the role of parking power generation and starting the engine;
2. Secondly, the P2 motor is placed near the gearbox, and the clutch is between the P2 motor and the engine. The P2 motor can be directly placed on the input shaft of the transmission, or it can be linked with the input shaft of the transmission through gear transmission. At this time, the P2 motor can drive the vehicle independently and realize energy recovery and power generation.
3. Thirdly, the P2 motor is placed between the engine and the transmission, and two clutches are added, so that the motor can drive the vehicle independently and start the engine.
The layout of the third structure makes it work more comprehensively and maximize the utilization rate. The working principle is that after starting the vehicle, the battery pack high-voltage system is ready to work. At the same time, the battery will supply power to the P2 motor, one of which is coupled, and the P2 motor will output power to the transmission, and finally drive the vehicle.
During driving, if more torque is needed or overtaking is required, the clutch with the engine will also be coupled, so that the engine and P2 motor form a series output mode, and the battery will also output electricity to provide energy for P2 motor.
When going downhill or braking, the clutch between the engine and the P2 motor is decoupled, and the wheels drive the P2 motor to reverse and charge the battery.
What are the advantages and disadvantages of using P2 structure?
Some people may be curious, why didn’t the DHT hybrid system with lemon platform under the Great Wall appear on the tank 300 HEV? Moreover, lemon DHT is a dual-motor system, and theoretically the mixing effect will be better than the known P2 structure. Let’s understand it this way. The lemon DHT hybrid is suitable for the models under the lemon platform, but it is not compatible with the models on the tank platform.
Therefore, structurally, the two are unlikely to appear at the same time; However, the tank wants to have a hybrid product, so it is easy to understand if the P2 structure is selected. One of the advantages of P2 structure is that it can improve the power performance and fuel economy with the minimum cost.
Compared with the motor structures of P0 and P1, the compatibility of P2 motor structure has been greatly improved. The structure of P2 motor is located between the gearbox and the engine, so it is not necessary to arrange it in the engine housing like P1 motor, so the layout form can be more flexible.
From the point of view of manufacturing new cars, P2 structure has the advantages of small transformation range, low cost and strong compatibility. So what are the disadvantages of this P2 structure?
P2 motor only stops driving the vehicle when the gearbox is switched to neutral, and then starts the engine. Because P2 structure is a single motor, it is difficult to give consideration to both power generation efficiency and power output at the same time, so one motor has to take care of both ends, which often leads to P2 structure not being able to achieve full coverage of various scenes.
At present, the systems used by other domestic brands, including DHT of Great Wall, are all dual motors, one for generating electricity and one for driving, which are the mainstream configurations.
It’s not helpful for off-road, and it’s friendly to fuel consumption.
The common application scenario of P2 structure is that it is applied to the weak mixing system and adopts the parallel arrangement of belts or gears, which can be compatible with the existing gearbox design, and is usually applied to the 48V weak mixing system by European brands, just like the first layout scheme mentioned above; The tank 300 HEV uses a set of 2.0T engine +1.7 kWh battery.
Can the tank 300 HEV you think of improve the off-road ability a lot?
The answer is no, don’t forget that most of our hybrid cars and plug-ins, fuel saving is the most important goal. For hard-core off-road SUVs, it is necessary to add a premise, that is, "guarantee off-road ability and reliability". Therefore, the ultimate goal of P2 hybrid for tank 300 HEV is to "optimize fuel consumption".
P2 motor can drive the vehicle independently. When going downhill and braking, the kinetic energy recovery system can also cut off the connection with the engine (decoupled from the engine), and it will move with the crankshaft like P0 and P1, thus losing kinetic energy. Because there is a transmission ratio with the output shaft, too much torque is not needed, and the size of the motor is not large, so that the performance of fuel economy can be better reflected while reducing the cost and weight.
If you really want to improve the off-road limit, you can use the dual-motor scheme of herdsman 4xe to generate electricity and drive the vehicle. In order to ensure the reliability, the driving mode can be automatically matched without intelligent real-time monitoring of the throttle opening and closing angle, but a pile of ECU and wiring harness can be saved to improve the reliability.
Perhaps for one reason, the tank 300 HEV was not allowed to do so. First, from the perspective of cost, the structural transformation of two motors and the cost of parts will rise. For this kind of thing, 500 PHEV tank is more suitable.
Finally, maybe in the product announcement stage, the hybrid system with P2 structure will be described emphatically, which can make the fuel consumption very low. After all, there is a large battery to support pure electric driving. Then, after feeding, the system structure of single motor may make the fuel consumption performance not as good as advertised, and other domestic brands have had similar situations in this regard.
The only difficulty that falls on the tank 300 HEV is to solve the disadvantage that the single motor inherent in the P2 structure cannot cover various working conditions.