There are two types of drive motors commonly used in new energy vehicles: permanent magnet synchronous motors and AC asynchronous motors. Most new energy vehicles use permanent magnet synchronous motors, and only a small number of vehicles use AC asynchronous motors.
Currently, there are two types of drive motors commonly used in new energy vehicles: permanent magnet synchronous motors and AC asynchronous motors. Most new energy vehicles use permanent magnet synchronous motors, and only a small number of vehicles use AC asynchronous motors.
Working principle of permanent magnet synchronous motor:
Energizing the stator and rotor generates a rotating magnetic field, causing relative motion between the two. In order for the rotor to cut the magnetic field lines and generate current, the rotation speed needs to be slower than the rotation speed of the stator’s rotating magnetic field. Since the two are always running asynchronously, they are called asynchronous motors.
Working principle of AC asynchronous motor:
Energizing the stator and rotor generates a rotating magnetic field, causing relative motion between the two. In order for the rotor to cut the magnetic field lines and generate current, the rotation speed needs to be slower than the rotation speed of the stator’s rotating magnetic field. Since the two are always running asynchronously, they are called asynchronous motors. Since there is no mechanical connection between the stator and the rotor, it is not only simple in structure and lighter in weight, but also more reliable in operation and has higher power than DC motors.
Permanent magnet synchronous motors and AC asynchronous motors each have their own advantages and disadvantages in different application scenarios. The following are some common comparisons:
1. Efficiency: The efficiency of a permanent magnet synchronous motor is generally higher than that of an AC asynchronous motor because it does not require a magnetizing current to generate a magnetic field. This means that under the same power output, the permanent magnet synchronous motor consumes less energy and can provide a longer cruising range.
2. Power density: The power density of a permanent magnet synchronous motor is usually higher than that of an AC asynchronous motor because its rotor does not require windings and can therefore be more compact. This makes permanent magnet synchronous motors more advantageous in space-constrained applications such as electric vehicles and drones.
3. Cost: The cost of AC asynchronous motors is usually lower than that of permanent magnet synchronous motors because its rotor structure is simple and does not require permanent magnets. This makes AC asynchronous motors more advantageous in some cost-sensitive applications, such as household appliances and industrial equipment.
4. Control complexity: The control complexity of permanent magnet synchronous motors is usually higher than that of AC asynchronous motors because it requires precise magnetic field control to achieve high efficiency and high power density. This requires more complex control algorithms and electronics, so in some simple applications AC asynchronous motors may be more suitable.
In summary, permanent magnet synchronous motors and AC asynchronous motors each have their own advantages and disadvantages, and they need to be selected according to specific application scenarios and needs. In high-efficiency and high-power-density applications such as electric vehicles, permanent magnet synchronous motors are often more advantageous; while in some cost-sensitive applications, AC asynchronous motors may be more suitable.
Common faults of new energy vehicle drive motors include the following:
- Insulation fault: You can use the insulation meter to adjust to 500 volts and measure the three phases of the motor uvw. The normal insulation value is between 550 megohms and infinity.
- Worn splines: The motor hums, but the car doesn’t respond. Disassemble the motor to mainly check the degree of wear between the spline teeth and the tail teeth.
- Motor high temperature: divided into two situations. The first is the real high temperature caused by the water pump not working or lack of coolant. The second is caused by the motor’s temperature sensor being damaged, so it is necessary to use the resistance range of a multimeter to measure the two temperature sensors.
- Resolver failure: divided into two situations. The first is that the electronic control is damaged and this type of fault is reported. The second is due to the real damage of the resolver. The sine, cosine and excitation of the motor resolver are also measured separately using the resistor settings. Generally, the resistance values of sine and cosine are very close to 48 ohms, which are sine and cosine. The excitation resistance differs by dozens of ohms, and the excitation is ≈ 1/2 sine. If the resolver fails, the resistance will vary greatly.
The splines of the new energy vehicle drive motor are worn and can be repaired through the following steps:
1. Read the resolver angle of the motor before repairing.
2. Use equipment to zero-adjust the resolver before assembly.
3. After the repair is completed, assemble the motor and differential and then deliver the vehicle. #electricdrivecyclization# #electricmotorconcept# #motorsinnovationtechnology# # motorprofessionalknowledge# # motorovercurrent# #深蓝superelectricdrive#
Post time: May-04-2024