What are the technical parameters of the drive motor of new energy vehicles?

New energy vehicles have three advantages: environmental protection, economy and simplicity. InPure electric vehiclesThis is particularly evident in the fact that the electric motor is used instead of the fuel engine, which is driven by the electric motor and does not need itAutomatic transmission

Compared with the automatic gearbox, the motor has simple structure, mature technology and reliable operation.

The speed of the traditional internal combustion engine when it can efficiently generate torque is limited to a narrow range, which is why the traditional internal combustion engine vehicle requires a large and complex transmission mechanism; The electric motor can efficiently generate torque in a fairly wide range of speeds, and does not need a gear shift device during the driving of pure electric vehicles, which is convenient and easy to operate, and has low noise.

with hybrid cars.

Compared with pure electric vehicles, which use a single electric energy source, the electronic control system greatly reduces the internal mechanical transmission system of the car, the structure is more simplified, and the energy loss and noise caused by the friction of mechanical parts are also reduced, saving the interior space and weight of the car.

The motor drive control system is the main executive structure in the exercise of new energy vehicles, and the drive motor and its control system are one of the core components of new energy vehicles (battery, motor, electronic control), and its driving characteristics determine the main performance indicators of automobile driving, which is an important component of electric vehicles.

Fuel cell vehicles in electric vehicles.

FCVs, hybrid electric vehicles, HEVs and pure electric vehicles all use electric motors to drive the wheels, and choosing the right electric motor is an important factor to improve the cost performance of various types of electric vehicles.

Therefore, it is extremely important to develop or improve the electric motor drive mode that can meet the performance requirements of the vehicle during driving at the same time, and has the characteristics of robustness, low cost and high efficiency.

The technical parameters of the drive motor of new energy vehicles mainly include the maximum output torque, the maximum power of the rated torque, the maximum output speed, the total load, the total reduction ratio, the amount of lubricating oil of the transmission, the type of lubricating oil of the transmission, etc. Hope it works for you.

New energy vehicles refer to the use of unconventional vehicle fuel as the power, comprehensive vehicle power control and drive of advanced technology, the formation of advanced technical principles, with new technologies, new structure of the car.

Types of new energy vehicles:

1. Pure electric vehicle is a kind of car that uses a single battery as an energy storage power source, which uses the battery as an energy storage power source to provide electric energy to the motor through the battery to drive the motor to run, thereby promoting the car to drive.

2. Hybrid vehicle refers to a vehicle whose drive system is composed of two or more single drive systems that can operate at the same time, and the driving power of the vehicle is provided by a single drive system alone or multiple drive systems according to the actual vehicle driving state.

3. Other new energy vehicles include vehicles that use high-efficiency energy storage such as supercapacitors and flywheels. At present, in China, new energy vehicles mainly refer to pure electric vehicles, extended-range electric vehicles, plug-in hybrid vehicles and fuel cell electric vehicles, and conventional hybrid vehicles are classified as energy-saving vehicles.

1. High voltage. As far as allowable, high voltages should be used as much as possible to reduce the size of equipment such as motors and wires, especially the cost of inverters.

2. High speed. The speed of the induction motor for electric vehicles can reach 8000-12000 rpm.

3. Small size and light weight. The weight of the motor can be reduced by using an aluminum alloy shell, and the materials of various control devices and cooling systems should also be made of lightweight materials as much as possible.

4. Large starting torque and wide range of speed regulation performanceto meet the power and torque required for starting, accelerating, driving, decelerating, braking, etc. The motor should have an automatic speed regulation function to reduce the driver's control intensity, improve driving comfort, and achieve the same control response as the accelerator pedal of an internal combustion engine vehicle.

5. The overload capacity is 4-5 timesto meet the requirements of short-term acceleration and maximum climbing ability.

Application features:

The reason why brushless DC motors are widely used in electric vehicles is that it has the following two advantages compared with traditional brushed DC motors.

1) Long life, maintenance-free and high reliability. In the brushed DC motor, due to the high speed of the motor, the brushes and commutators wear out quickly, and the brushes need to be replaced after about 1000 hours of work. In addition, the technical difficulty of its reduction gearbox is greater, especially the lubrication problem of the transmission gear, so the brush motor has problems such as high noise, low efficiency and easy failure.

Therefore, the advantages of brushless DC motors are obvious.

2) High efficiency and energy saving. Generally speaking, the efficiency of brushless DC motors can usually be higher than 85% because there is no mechanical commutation friction loss, gearbox consumption, and speed regulation circuit loss, but considering the highest cost performance in the actual design, in order to reduce material consumption, the general design is 76%. The efficiency of a brushed DC motor is usually around 70% due to the consumption of the gearbox and the overtaking clutch.

The function of the drive motor is to convert the electrical energy of the power supply into mechanical energy, either through the transmission or directly drive the wheels and working devices. At present, DC series motors are widely used in electric vehicles, which have soft mechanical characteristics and are very consistent with the driving characteristics of automobiles. However, due to the reversing spark, the DC motor has low power, low efficiency and large maintenance workload; With the development of motor control technology, it is bound to be gradually replaced by brushless DC motors (BLDCM), switched reluctance motors (SRM) and AC asynchronous motors, such as caseless disc axial magnetic field DC series motors.

The motor speed control device is set for the speed change and direction change of the electric vehicle, and its function is to control the voltage or current of the motor and complete the control of the driving torque and rotation direction of the motor.

In the early days of electric vehicles, the speed regulation of the DC motor was achieved by connecting the resistors in series or changing the number of turns of the motor's magnetic field coil. Because of the step-by-step speed regulation, additional energy consumption or complex structure using electric motors, it is rarely used now. At present, the most widely used is thyristor chopper speed regulation, which controls the current of the motor by uniformly changing the terminal voltage of the motor to achieve stepless speed regulation of the motor.

In the continuous development of electronic power technology, it is also gradually replaced by other power transistors (into GTO, MOSFET, BTR, IGBT, etc.) chopper speed control devices. From the perspective of technological development, with the application of new drive motors, the transformation of speed control of electric vehicles into the application of DC inverter technology will become an inevitable trend.

In the rotation conversion control of the driving motor, the DC motor relies on the contactor to change the current direction of the armature or magnetic field to realize the rotation transformation of the motor, which makes the circuit complex and the reliability is reduced. When the AC asynchronous motor is used, the change of motor steering only needs to change the phase sequence of the three-phase current of the magnetic field, which can simplify the control circuit. In addition, the use of AC motor and its frequency conversion speed control technology makes the braking energy of electric vehicles more convenient to control, and the control circuit is simpler.

The braking device of an electric vehicle, like other cars, is set up for the car to slow down or stop, and usually consists of a brake and its control device. In

On electric vehicles, there is generally an electromagnetic braking device, which can use the control circuit of the driving motor to realize the power generation operation of the motor, so that the energy during deceleration and braking is converted into the current of charging the battery, so as to be recycled. At present, domestic electric vehicles in high-power passenger vehicles, to provide air braking equipment has endurance naili sliding vane air compressor, mainly compressed air braking mode.

The performance indicators include rated power, peak power, rated speed, peak speed, rated voltage, working voltage, etc.

New energy vehicles refer to the use of unconventional vehicle fuel as the power (or the use of conventional vehicle fuel, the use of new on-board power units), the integration of advanced technology in the power control and drive of the vehicle, the formation of advanced technical principles, with new technologies, new structure of the car.

New energy vehicles include pure electric vehicles, extended-range electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, hydrogen engine vehicles, and other new energy vehicles.

Low cost of use. The power consumption of 100 kilometers is about 8 yuan, which is about the same as that of 1 liter of fuel.

2. There is no limit. In large cities, the number is generally limited, and new energy does not have this trouble.

3. The driving is stable, and there is no shift impact. Most of the gearboxes for new energy are single-speed gearboxes, and there is no shift impact.

4. More environmentally friendly. Make contributions to the cause of environmental protection within our ability.

At present, the mainstream drive motor has three forms: centralized, wheel side type and hub type, all of which are permanent magnet synchronous motor technology, and the difference is only that the motor is installed in the position of the vehicle.

Type of drive motor:

1. Centralized drive motor: The centralized drive motor is the most similar to the traditional axle, and it must pass through transition parts, such as reducer and transmission shaft, when driving the wheel. At present, most low-speed electric vehicles are basically this kind of structure, mainly because this type of structure is the simplest and cheapest.

Another problem with these low-speed electric vehicles is that the transmission is generally omitted. This brings up the problem of insufficient low torque when starting or climbing; Then there are the disadvantages of relatively large volume and low transmission efficiency.

Therefore, there are many models that simply use dual-drive motors to make up for the lack of power, which is also the reason why the proportion of four-wheel drive in new energy vehicles is much higher than that of traditional cars, and it also explains why many of those Internet-made car launch models are mostly SUVs.

At present, the mainstream of the market is centralized drive motor + traditional axle, because of its structural characteristics, the traditional axle can be matched as long as it is slightly modified, so it can reduce very large R & D costs.

2. Wheel-side drive motor: The wheel-side structure needs at least two drive motors, of course, it may be more. Two drive motors are arranged on both sides of the axle to drive a single wheel by reducing the torque through the side reducer and the wheel side reducer.

The wheel motor may or may not need a drive shaft, which is what makes it different from a centralized drive motor.

But relatively centralized, the wheel side type is of great significance to the chassis layout of the whole vehicle, especially in the case of rear axle drive, the traditional car has to transmit the power of the front transmission to the rear wheel through a long transmission shaft, which will have a lot of impact because of the deformation movement between the body and the wheels, but the wheel drive motor can be directly installed on the side of the wheel, so there is no need to consider too many factors such as torsional deformation, so the chassis can be made very flat, and the body can also be more varied.

3. Hub drive motor: To put it simply, the hub motor is to install everything in the hub, such as the drive motor, reducer, etc. The biggest advantage is that it is compact, eliminating the need for differentials, half-shafts and variables.

At the same time, because the mechanical loss of these structures is reduced, the transmission efficiency is correspondingly improved. (Photo by Dong Peng) @2019

There are three mainstream motors for new energy vehicles: DC motors, asynchronous motors, and permanent magnet synchronous motors. Motor is a kind of power component that converts electrical energy and mechanical energy into each other. When electrical energy is converted into mechanical energy, the motor exhibits the working characteristics of the motor; When mechanical energy is converted into electrical energy, the motor exhibits the working characteristics of the generator.

In most electric vehicles, the mechanical energy will be converted into electrical energy when the brakes are braking, and the battery will be recharged through the generator.