At present, the application mode of motor architecture in the industry is different, and the specific application and interpretation under different architectures are also slightly different. The starting point of this paper is to sort out the basic principles and application modes of p0-p4 architecture and the uses of different combination schemes.
● Definition and analysis of P0-P4 motor
In the hybrid electric vehicle, according to the different motor positions, it can be divided into P0-P4 and Ps architectures, where P stands for motor position, and the motors in different positions play different roles, which is directly related to the energy consumption and dynamic performance of the vehicle. Which hybrid electric car is more suitable for you?
◆P0 architecture: simple structure and early fame?
The motor with P0 structure is installed at the front end of the engine and connected with the crankshaft of the engine through a belt. Vehicles equipped with P0 motor can drive the mechanical compressor of air conditioner to run when the engine stops at the traffic lights, so as to realize engine start-stop, braking energy recovery for power generation and auxiliary power output.
"Bosch 48V? MHEV system "
P0 architecture is relatively simple in technology and structure and widely used. The automatic start-stop system that many drivers and friends shut down when they get on the bus is a typical P0 architecture, and the history of automatic start-stop can be traced back to the 1970s. Compared with vehicles equipped with automatic start-stop function, P0 architecture adopts BSG (belt drive? Starter/generator; Belt-driven starter/generator) motor, equipped with a large battery, can be competent for driving compressor and auxiliary engine.
When the engine is stopped, P0 motor can drive the air-conditioning compressor to work independently, reducing the idle time of the engine; When the vehicle starts or accelerates, P0 motor can assist the engine to run, help the engine quickly get rid of the inefficient working range, save fuel and effectively improve driving quality. Because P0 motor transmits power to the wheels in series, without the engine, the motor cannot drive the wheels independently, so there is no pure electric drive mode. In addition, the P0 motor is flexibly connected with the crankshaft through a belt, so the ceiling for exerting force on the engine and recovering kinetic energy is low.
"2020 changed Mazda CX-5? 2.5L？ Automatic four-wheel drive intelligent model "
Audi SQ7? The weak hybrid system of TDI and Mazda i-Eloop belongs to P0 architecture. Due to the low transmission efficiency of P0 frame, the motor can not directly drive the wheels, so in the field of new energy vehicles, P0 motor usually appears in the form of auxiliary. There will be corresponding analysis and cases below.
◆P 1 architecture: independent research and development/high integration.
The P 1 motor is located at the rear end of the engine crankshaft, replacing the traditional flywheel. P 1 motor not only inherits the function of flywheel to store energy and inertia outside the engine power stroke, but also has similar functions as P0 motor, supporting engine start and stop, braking energy recovery, power generation and auxiliary power output.
Honda IMA hybrid power system
Compared with P0 architecture, P 1 architecture is more compact, and its motor is integrated in the engine housing. In the design, the volume of the engine and the layout in the engine room need to be considered, and corresponding design schemes are needed for different gearboxes, so the R&D and manufacturing cost of P 1 motor is relatively high. Existence is reasonable, and often high investment corresponds to high return. As the rotor of P 1 motor, the engine crankshaft has higher power transmission efficiency, better fuel saving effect and more obvious driving performance improvement. In addition, the P 1 motor can exert auxiliary braking torque through electromagnetic field adjustment on downhill sections to improve safety.
P0 architecture and P 1 architecture are different in location, but they are related to the same disease. As long as the motor rotates, the engine crankshaft must rotate, so the motor cannot drive the wheels alone, and there is no pure electric drive mode. In the kinetic energy recovery and coasting mode, because the crankshaft must be driven to idle speed, kinetic energy is wasted, and noise and vibration are also increased because the internal combustion engine follows.
"Mercedes M254 Engine"
"2020 Mercedes-Benz E-Class (imported)"
A few days ago, the M254 model launched by Mercedes-Benz overseas adopted 2.0T? 4-cylinder engine, and added 48V light mixing technology in the process of electrification transformation. The maximum power of ISG motor is 12kW, and the peak torque is180n m, which alleviates the performance of turbine lag when the wheel starts to accelerate. The system is a typical P 1 architecture. The official name of the motor is "? FAME "(modular engine), some foreign media speculated that this motor will appear on other PHEV models.
◆P2 architecture: modular design/strong fuel economy and wide application?
P2-frame motor is located between the engine and gearbox, because it does not need to be integrated in the engine housing like P 1 motor, so the layout can be more flexible. Structurally, a 1-2 clutch can be arranged between the engine and the gearbox, which can be divided into three arrangements: ① a single clutch structure in which the motor is arranged in front of the clutch, and the motor plays the role of assisting, parking power generation and starting the engine, similar to the P 1 structure; (2) Single clutch structure, in which the motor is arranged behind the clutch, so that the motor can drive the vehicle independently, recover braking energy, generate electricity and assist; ③ The motor is arranged in the middle of the double clutch structure, so that the motor can drive the vehicle independently, or start the engine or stop to generate electricity.
P2 architecture has strong compatibility and can match all gearboxes (including manual gearboxes). P2 architecture is widely used in hybrid vehicles, and many parts suppliers have mature solutions. Take the P2 motor module of Borgwarner as an example. It integrates dual-mass flywheel and engine clutch, which can disconnect the clutch and motor direct-drive vehicle. It can convert an internal combustion engine-powered vehicle into a hybrid vehicle without changing the engine and gearbox, which means that car companies can expand the power combination of vehicles and enrich the product line of hybrid vehicles with less investment, shorter time and greater flexibility.
"Audi A3? Electron accelerator power supply system "
"20 17 Audi A3 new energy (imported) Sportback? E-tron comfort type "
Audi A3? E-tron is a representative model of P2 architecture, equipped with 1.4T engine and permanent magnet synchronous motor with maximum power of 75kW. The battery capacity of the car is 8.8 kWh, and the pure electric cruising range under NEDC condition is 50 kilometers.
P3 Building: Efficient Power Transmission and Large Space Occupancy?
P3 frame motor is located at the output end of gearbox, with high efficiency of pure electric drive and kinetic energy recovery, and the effect of rapid acceleration is very direct. In terms of function, P3 motor can realize braking energy recovery and pure electric drive vehicles. Because the motor can't be integrated with gearbox or engine, it needs to occupy extra volume, so P3 architecture is more suitable for rear-wheel drive and has enough space for layout.
Compared with P0, P 1 and P2 architectures, the power transmission path of P3 architecture does not pass through the gearbox, so the efficiency of pure electric drive and braking energy recovery is higher, and the working time of the gearbox is also reduced, which is helpful to prolong its service life. However, the problem is also obvious. P3 cars can't stop and charge, and the shortcomings of outdoor camping and other usage scenarios are exposed.
The representative model is BYD Qin, which is a parallel hybrid vehicle with automobile as the core. With the original large-capacity battery setting, it can not only satisfy China's pure battery life of 50 km for PHEV, but also stack the performance of engine and motor to achieve stronger power output.
◆P4 Building: realize four-wheel drive.
P4 frame motor and engine do not drive the same shaft, thus helping the vehicle to realize four-wheel drive. It can be a motor that drives the front axle/rear axle, or it can simply cancel the axle like Acura NSX and directly use two hub motors to drive the wheels. P4 building is similar to P3 in function, which can realize braking energy recovery and pure electric drive vehicles.
"2020 BMW i8 Extreme Night Meteor Limited Edition"
P4 architecture is mostly used for plug-in hybrid vehicles, and sports cars are more commonly used, such as Porsche 9 18? Spyder, Acura NSX, BMW i8 and other sports cars. Take BMW i8 as an example. This 1.5T three-cylinder engine squeezes out the maximum power of 23 1Ps and the maximum torque of 320 N m. The maximum power of the permanent magnet synchronous motor at the front axle is 13 1Ps and the peak torque is 250N·m, and it is equipped with a two-speed automatic gearbox to adjust the torque.
◆Ps architecture: parasites of double clutch
P3 motor is coupled to the output end of the gearbox, and Ps motor is directly integrated inside the gearbox. Ps architecture is easily confused with P3 architecture because of its close location distribution. Ps architecture is based on dual-clutch gearbox, which has two input shafts, and the motor is integrated on one shaft, which can realize pure electric drive vehicle and braking energy recovery.
"PS architecture power transmission mode"
The motor, clutch and reducer with Ps structure are placed in the same shell, which is more fuel-efficient and smoother. However, the disadvantages are also obvious, because the even shaft of the dual-clutch gearbox bears more torque than the odd shaft, which will lead to the inconsistency between the two shafts and the wear of the clutch; In addition, integrating the motor into the gearbox will increase the maintenance cost, because it is the gearbox assembly that needs to be disassembled regardless of gearbox failure or motor failure.
"202 1 borui new energy 1.5T? Epro leading edition "
At present, among China brand car companies, Great Wall, Chery and Geely are all studying DHT gearbox, which is the cornerstone of Ps architecture. Taking Geely Automobile as an example, the plug-in hybrid system of 1.5T+7DCTH of Geely ePro family has the characteristics of high motor efficiency and high powertrain matching, and has the comprehensive advantages of high efficiency, excellent space and good quality (high cost performance). The efficiency of Ps frame motor is 97%, which is about 2% higher than that of P2 coaxial motor. The working speed of Ps frame motor is not limited by the engine, and the engine and motor can work in the high efficiency area at the same time, which can effectively reduce the fuel consumption of the whole vehicle.
● Combined frame motor
Brother-to-brother, father-son and single-structure motors all have some shortcomings, so combining two or more structures of motors has become the best solution at present. In P3 or P4 frame cars, in order to perform engine start-stop and power generation functions, it is necessary to install another motor for the engine, so many hybrid electric vehicles have two motors, forming a combined configuration of Px+Py. Like WEY? P8, the front end of the engine has BSG motor, and the rear axle has permanent magnet synchronous motor, which belongs to P0+P4 configuration. Let's understand the technical characteristics of combined structure motor through the development of domestic and foreign car companies and vehicle type analysis.
◆ Volvo PHEV Technical Review and T8 Power System Analysis
20 13 Volvo plug-in hybrid (PHEV) technology applied to S60? The PHEV adopts P0+P4 architecture, which consists of 1 BSG motor with engine front power of 15kW and 1 50kW permanent magnet synchronous motor with rear drive axle. 20 15 Volvo second generation PHEV technology applied to XC90? On the PHEV model, P 1+P4 architecture is adopted, which consists of 1 ISG motor with power of 35kW and 60kW permanent magnet synchronous motor on the rear drive axle. At present, Volvo adopts the third generation PHEV technology based on CMA vehicle platform, and adopts a hybrid powertrain composed of engines matched with P2 motor.
In terms of specific models, Volvo XC90? PHEV adopts a hybrid power system with P 1+P4 architecture, and the front axle of the vehicle is equipped with a vehicle named C-ISG(Crank-integrated? Starting? The integrated motor of gearbox has three functions: start-stop control, power generation and power assistance, and the rear axle is also equipped with a motor with the maximum power of 65kW. At present, Volvo's PHEV models cover cars, station wagons and SUVs, all of which adopt modular PHEV power systems.
◆ Evolution history of BYD DM system and analysis of the third generation DM system.
Since 2008, BYD DM system (dual? Mode system) has been upgraded twice. At present, the upgrade of the third generation DM plug-in hybrid is not only in terms of power. After the "542" plan was put forward from the second generation DM system, the whole BYD model was further upgraded in "performance".
"High power consumption" is an obvious problem in the second generation DM system. BYD thinks that BSG motor+electronic control system can solve the problem of "avoiding the inefficient engine area", assist the vehicle to generate electricity, make the whole energy flow system more balanced and bring better acceleration performance, so the brand-new "BSG architecture" system is one of the core upgrades of this generation of DM3.
The biggest use of BSG motor of the third generation DM system is not only to provide start-stop function servo for the engine, but also to charge the power battery during driving and improve the acceleration performance. When the vehicle is driving in the all-electric drive mode, when the engine is involved, the BSG motor will drive the engine to start, so as to reduce vibration and assist gear shifting.
Full text summary:
With more and more strict emission standards and support policies for new energy vehicles, automakers pay more and more attention to the new energy market. Compared with the development of a new hybrid power system, the P2 technical route with modular design does not need to change the existing structure, is easy to integrate and is suitable for matching all gearboxes. Even if the fuel saving effect is not as good as parallel connection, it can reduce fuel consumption at a lower cost, which has become a "shortcut" for many car companies. (Text/car home? Zhang Wenhao)