Comprehensive Interpretation of Roewe E50 Pure Electric Vehicle Technology

On the evening of November 5, 2012, SAIC's first mass-produced pure electric vehicle, Roewe E50, was officially released at the Shanghai World Expo Center. Roewe E50 is a pure electric vehicle developed based on the new vehicle platform and independently mastering the core technology of "three electricity". What are the technical highlights of this pure electric car positioned as an urban boutique? The technical experts of SAIC Group gave us a relevant introduction. Let's interpret it for you. fashionable and flexible designDolphin hatchback body design. The appearance design of Roewe E50 comes from the E1 concept car, but it simplifies many sci-fi advanced elements. It adopts the dolphin short kiss hatchback body design, which looks full. The tail gate adopts the dolphin back integrated design, the overall appearance line is round, in line with the aerodynamic principle, which helps to reduce the wind resistance coefficient of the whole vehicle.

The single chamber shape design is adopted for the headlights, and the popular LED is embedded below, which matches with the LED tail lights at the rear of the vehicle, making the whole vehicle more dynamic.Because it is a pure electric vehicle, there is no air inlet grille of traditional vehicles in the front of the front, and there is a shield type plug-in cover (quick charging socket) in the middle. The blue e word is placed in the middle, which makes it easier to identify its electric identity. The other household electric socket is located on the left rear hand side, which is the traditional refueling position.The interior design is simple. The E50 adopts a three piece multimedia centralized control steering wheel with silver sports trim embedded below, which is dynamic as a whole. The instrument panel adopts multi-functional digital instruments with 3D effect, which exudes fashion and beauty. The intelligent integrated man-machine exchange system is located in the middle of the central control. The display screen is a 6.5-inch touch screen, which looks full of a sense of science and technology.

E50, as a two door trolley, adopts 2 2 interior space layout. The front and rear seats are in black and white, integrated with the central control.As an A00 class car, the wheelbase of Roewe E50 axle is 2305mm. Because the whole vehicle is based on the new design of electric vehicle, after reasonable optimization, there is still plenty of space in the vehicle.E50 also adopts the popular one button start function, but the slight difference is that the one button start button is integrated on the key, which can be started by inserting the key. It is worth mentioning that the Roewe E50 is also equipped with a humanized smart hold electronic handbrake system, which has the functions of automatic flameout, automatic parking of the rear shell after pulling out the key, Hill assisted starting and so on, which helps to improve driving safety.

exclusive vehicle platform for pure electric vehiclesThe Roewe E50 listed this time is a newly developed vehicle platform for the design of pure electric vehicles, which is different from most pure electric vehicles refitted from the internal combustion engine vehicle platform in China. At the beginning of the design, it was developed around this pure electric vehicle platform, which can avoid a series of problems on those "modified pure electric vehicles", such as the battery pack occupying the boot space, the uneven weight distribution of the front and rear axles caused by the installation of batteries, and so on.The drive system (motor and integrated electronic box) of E50 is placed at the front of the vehicle, the power battery pack is arranged slightly behind the bottom of the vehicle body, and the 12V battery is placed at the bottom of the trunk. The front suspension is McPherson independent suspension and the rear suspension is H-shaped torsion beam semi independent suspension.

It is reported that Roewe E50 has considered the component layout of pure electric vehicle at the beginning of design. Through reasonable optimization, it not only ensures the safety of the whole vehicle, but also improves the handling and space utilization of the vehicle. You can have an in-depth experience in this future test drive. "three electricity" core technologyMotor, electric control and battery ("three electricity") have always been the technical bottlenecks in the development of electric vehicles. Let's learn about the characteristics of the "three electricity" core technology on Roewe E50 small electric vehicle?

Lithium iron phosphate battery. In fact, as a pure electric vehicle driven by electricity, the battery is the source of all power. Its good or bad performance directly affects the effective use of electric vehicles. Roewe E50 adopts lithium iron phosphate battery. What are the advantages of this battery over traditional batteries? We should know that the traditional battery has memory. If it often works under the condition of full charge, the capacity will be lower than the rated capacity.This lithium iron phosphate battery has no memory characteristics, has higher charge and discharge efficiency, and is more suitable for frequently charged electric vehicles. In addition, the weight of lithium iron phosphate battery with the same specification and capacity is lighter than that of traditional lead-acid battery.According to the relevant technical director, the power of lithium iron phosphate battery carried by Roewe E50 is very stable. The self discharge in three months is no more than 5%. At minus 20 degrees, the battery capacity attenuation is less than 10%. Moreover, after 2000 impulse discharges, the battery loss is still less than 20%, and the actual service life is more than 10 years. In addition, the battery module has a temperature control system, which can effectively prevent the battery from overheating. The effective range of Roewe E50 under 60km constant speed condition is 180km.

Permanent magnet synchronous motor integrated electronic box drive system. In addition to battery, electric drive system is also an important part of pure electric vehicle. The maximum power of Roewe E50 is 52kw, the peak torque reaches 155nm, the acceleration of 0-50km is 5.3s, and the maximum speed reaches 130km / h. for a pure electric car walking in the city, the power is enough.The motor adopts the permanent magnet synchronous motor independently developed by Roewe. The overall waterproof and dustproof design has high stability. The matching is an integrated power electronic box, which integrates the inverter and high and low voltage DC converter, reduces the volume and weight of the electronic box to a certain extent, which is conducive to the chassis layout of this small car.VCU intelligent vehicle control system. The VCU intelligent vehicle controller jointly developed by SAIC and Bosch has more than 20 ECU control units and integrates the international advanced CAN-bus system, which can effectively improve the transmission speed between external controllers, so as to ensure the stability and safety of the system.

CAN-bus management system mainly includes powertrain and chassis management bus, OBD2 digital diagnosis management bus, multimedia management bus and body management bus. vehicle safety protection systemWhether it is a traditional internal combustion engine vehicle or a pure electric vehicle, its safety performance is also what we pay most attention to. For electric vehicles, whether the battery system can be well protected in collision is also very important.

Lightweight body structure. As a small car, its safety performance is also of great concern to us. Especially for small cars with very compact body structure, the materials used in body design are more important because there is not too much space to cushion the impact force. On the other hand, the body should not be too heavy, otherwise it will affect its handling and energy saving.The body of Roewe E50 adopts lightweight materials and ultra-high strength steel structure. The cab adopts ultra-high strength steel structure, the front buffer beam is made of aluminum alloy, and the tail gate is made of SMC composite lightweight material. The charging port, small door and PEB beam are also replaced by new synthetic materials.According to reports, the power battery compartment at the bottom of the vehicle body is also equipped with an anti-collision structure, and ultra-high strength steel is used as a support at its key stress points, which can ensure the safety of the battery in extreme collisions.

Only by using high-strength materials and effective optimization can the body achieve good cushioning and energy absorption when impacted by impact force, so as to protect the safety of drivers and passengers. Since E50 is designed based on the pure electric vehicle platform, the balance between ergonomics and vehicle safety is considered in the design of motor, battery and vehicle body. Roewe E50 is designed according to C-NCAP four-star anti-collision safety standard, and has conducted strict collision test according to strict American standards. The results are all safe, qualified and meet the design requirements.Battery protection system. The power battery can be said to be the "heart" of pure electric vehicles. The protection of the "heart" is very important, especially in the process of wading and collision. Due to the characteristics of the power battery, it is easy to cause leakage or fire.Now most of the power batteries of pure electric vehicles are arranged under the body, and the environment is also very bad. Walking on rainy days and dusty roads is a severe test for the battery. According to technical experts, the waterproof and dustproof ability of Roewe E50 power battery has reached the high standard of IP67.

The waterproof and dustproof grade is one of the most stringent automobile test standards at present. For example, for batteries that meet the IP67 standard, no dust intrusion is found after 6 hours in an environment filled with very fine particles of dust; The battery is immersed in water for half an hour, and the seal will not fail. In addition, because the power battery works in a high-voltage environment, the insulation design of the vehicle body and the protection of collision and power failure are also particularly important. braking energy feeding systemEnergy saving and environmental protection technology of capacity recovery is a major feature of electric vehicles. Roewe E50 pure electric car also uses this technology. How does the brake energy feed system of E50 work? The principle is also very simple. When the vehicle is decelerating, the motor is driven to reverse through the motion inertia of the vehicle, and then the power battery is charged, which reduces the energy loss during braking, which is also helpful to increase the mileage.

In fact, this method is somewhat similar to the traditional use of engine traction for braking, where the motor replaces the engine. In this way, while charging the battery, it can also improve the braking efficiency and reduce the braking distance. On the other hand, it can also reduce the wear of brake pads.

Conclusion: different from other pure electric vehicles transformed from traditional vehicles, Roewe E50 is a small car redesigned based on electric vehicles. In terms of body layout, it has undergone a series of reasonable optimization, so that although the car is small, it also has "five internal organs", which integrates the "three electricity" of SAIC's power battery system, electric drive system and electronic control system The core technology makes the car perform well in terms of performance. For the future performance of this pure electric car positioned for urban walking, we still have to accept the test of the market.