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"In fact, in the field of electric vehicle research and development, one of the most important issues is how to solve the problem of in-wheel motors.

Jin Xiaoqiang asked Fang Shanhai, as a designer who has been engaged in automobile design for many years, Fang Shanhai certainly knows what this hub motor is.

Although he has not been engaged in the research and development of new energy vehicles, he is still very clear about the concept of this new energy vehicle field.

And because he has been engaged in the research and development of concept trucks, he has long been familiar with this kind of wheel electric drive technology that has been applied to large trucks for a long time, and his own research on this technology is also quite accomplished and has his own opinions.

You must know that in the next few years, the two large concept trucks he designed himself used this kind of wheel drive technology.

It's just that he hasn't thought about this aspect before, so he didn't understand the all-wheel drive technology mentioned by Jin Xiaoqiang on the drawings before, and now Jin Xiaoqiang mentioned the hub motor drive, he immediately understood Jin Xiaoqiang's thoughts on this car, and he didn't understand what he didn't understand when he looked at the drawings before, but at this time, it was all through in an instant, and he knew it in his chest.

The key to this technology is actually to integrate a drive motor into the wheel hub, and then directly transmit power to this motor through the on-board battery or engine to achieve the purpose of rotating the wheel hub, so as to make the wheel rotate and the vehicle can drive on the road.

In this way, the mechanical devices required on the original car will be omitted, so as to reduce the weight of the body, simplify the mechanical structure and a series of problems.

As early as 1900, Porsche had manufactured an electric vehicle equipped with a drive motor for the front wheel and front wheel hub, and later in the seventies of the 20th century, General Motors installed this wheel hub on a large mine dump truck, and later this technology was widely used in the city to use the public transport vehicles with frequent passengers getting on and off.

In the nineties of the twentieth century, a Japanese automobile manufacturer launched a large number of in-wheel motor driven vehicles, such as Mitsubishi once launched a in-wheel motor driven Lancer EVO, and Honda also launched RCX and other models.

Later Americans were not far behind, and in 2002, GM also launched a series of concept models with in-wheel motor drive, such as the Autonomous Magic and Squel.

However, due to various reasons, these models were not able to be mass-produced in large areas in the end.

Now in the development of this in-wheel motor drive, the Japanese are currently at the forefront of the world.

At present, this in-wheel motor drive technology, in large commercial vehicles, or the use of trucks, is not very backward, GM even once for its 150-ton heavy crime transport truck, specially developed a hub drive motor driven by an internal combustion engine, and has been used very well.

The drive mode of in-wheel motor is also divided into two modes: internal rotor and external rotor, and the traditional drive mode in the past generally adopts the drive mode of external rotor.

The external rotor type uses a low-speed external transmission motor, the maximum speed of the motor is 1000-1500r/min, there is no deceleration device, and the speed of the wheels is the same as that of the motor.

The internal rotor type adopts a high-speed internal rotor motor equipped with a reducer with a fixed transmission ratio, and the speed of the motor can be as high as 10,000r/min in order to obtain a higher power density.

With the advent of more compact planetary gear reducers, in-wheel motors are becoming more competitive in terms of power density than low-speed out-rotor motors, and are becoming more and more popular.

Models that use in-wheel motors can be said to have many advantages over conventional models with internal combustion engines.

Generally for traditional vehicles, clutches, transmissions, drive shafts, differentials and even transfer cases are essential parts of the whole vehicle, and these components are not only not lightweight, but also make the structure of the vehicle more complex, and there are also problems that require regular maintenance and failure rates. …,

But the in-wheel motor solves this problem very well, and he can use the above-mentioned clutch, transmission, transmission shaft, differential and other parts to disappear in the car, making the structure of the body simpler.

In addition to the simpler structure, the vehicle driven by the in-wheel motor can obtain better space utilization, and the transmission efficiency is also much higher.

The second advantage of using the in-wheel motor drive is that the in-wheel motor makes the vehicle have the characteristics of independent drive of a single wheel.

Therefore, whether it is front-wheel drive, rear-wheel drive or four-wheel drive, it can be achieved relatively easily.

The full-time all-wheel drive system, which used to be a headache for countless automotive engineers, is very easy to implement in vehicles driven by in-wheel motors.

At the same time, the hub motor can realize the differential steering similar to the tracked vehicle through the different speeds of the left and right wheels or even the reversal, so that the turning radius of the vehicle can be greatly reduced, and even the in-situ steering can be realized under special circumstances, of course, this will cause greater wear and tear on the vehicle steering mechanism and tires, but it is very valuable for special vehicles.

The third point of in-wheel motor drive is that it can be applied to various energy drive technologies, whether it is internal gas, pure electric vehicles, hybrid vehicles, or fuel cell vehicles, this technology can be adapted to various power drive technologies.

As far as the current new energy vehicles are concerned, many of them use electric drives, so the in-wheel motor drive also comes in handy.

Whether it is a pure electric or fuel cell electric vehicle, or an extended range electric vehicle, the in-wheel motor can be used as the main driving force.

Even for hybrid vehicles, the in-wheel motor can be used as a boost for starting or accelerating, which can be described as a multi-purpose machine.

At the same time, many technologies of new energy vehicles, such as braking energy recuperation, that is, regenerative braking, can also be easily implemented in in-wheel motor drive models.

However, the in-wheel motor drive technology is not without its shortcomings, and the biggest challenge he is facing at present is his two shortcomings.

His first disadvantage is that the use of in-wheel motor device will greatly increase the mass under the spring of the car's suspension, and another problem is the moment of inertia of the in-wheel motor, both of which will greatly affect the driver's handling of the car.

For the current ordinary civil vehicles, the majority of manufacturers often use some relatively lightweight materials such as aluminum alloy to make suspension parts, in order to reduce the unsprung mass and improve the response speed of the suspension.

However, the in-wheel motor happens to increase the unsprung mass to a large extent, and also increases the moment of inertia of the hub, which is not conducive to the handling performance of the vehicle.

However, if such an in-wheel motor is applied to electric vehicles or hybrid vehicles, considering that most of such new energy models are limited to transportation, rather than the pursuit of power performance, this is not a major defect.

For large trucks or buses, handling is not in the scope of consideration, for such large transport vehicles, energy saving, slow speed, safety are the key elements to consider.

The second disadvantage of in-wheel motor drive is the fatal defect of this drive system, and the reason why this in-wheel motor drive technology has not been able to be popularized on a large scale is precisely because of this shortcoming.

This problem is the problem of sealing and heat dissipation!

Obviously, this drive system is to integrate the motor into the wheels, so that when the car is driving on the road, it often encounters some particularly complex road conditions.

For example, if the car has to wade in water, or take some bad roads, it will be very strict to assess the sealing problem of the motor system of the car.

Because if water enters the motor, or dust comes in, it will greatly affect the driving function of the motor. …,

And when the motor is working, it will also produce a lot of heat, and because the special wheel part where the motor is located, it is difficult for you to be able to match these motors with a water cooling device on the part of this hub, and if the air cooling situation is adopted, once the vehicle is working in summer or in the future, the temperature on the road is often higher than the air, especially in the congested urban traffic environment of stop-and-go.

In this way, once the heat dissipation is not good, it is easy to cause the problem of the motor being burned out.

If the method of opening holes for the motor is used to dissipate heat, this contradicts the requirements of the motor for sealing and waterproofing and dustproof, so this has become the most fatal shortcoming of the in-wheel motor.

Even the world's largest in-wheel motor manufacturer, Canada's TM4, and the United States' Wavecrest are struggling to solve this problem.

Therefore, replacing the motor regularly, or maintaining the motor, also poses a big problem to the cost of using the car!

And the car that uses such in-wheel motor drive technology will also face the problem of braking energy consumption, but this is for hybrid or pure electric vehicles, if it is a model that uses an internal combustion engine, it will not face this problem, so this is not a big problem.

The above-mentioned technical shortcomings of the hub electric drive may be a big problem for other companies, but for Huayang Power and Jin Xiaoqiang, it is not a big problem.

Especially for this kind of sealing and heat dissipation problems, you must know that most of the hub motors currently used in the world are air-cooled structures, and many use water-cooled or oil-cooled structures, but the cost of using water-cooled and oil-cooled hub motors will also be relatively high.

Water cooling is due to a complex system, and oil cooling is due to the cooling oil that needs to be used, but this problem is not a problem at all for Jin Xiaoqiang, who has a special cooling oil.

And since he can have a special cooling oil, he believes that he can also make a special sealing oil......

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