Which of the BLDC motors and DD direct-drive motors often mentioned when buying washing machines is better?
Now when choosing a washing machine, in addition to the capacity, appearance, and function, the motor is also included in the consideration. Xiaomei today will give you the common differences between BLDC motors and DD direct drive motors in popular science. First, let’s distinguish between direct drive and non-direct drive:
Direct drive: The motor directly drives the wave plate or inner drum of the washing machine through (or without) the clutch without belt transmission.
Direct drive: The motor is driven by a belt and drives the wave plate or inner drum of the washing machine through (or without) the clutch.
The common DD before direct drive, the full name is direct drive, and it is also direct drive when translated into Chinese. Direct drive means that there is a direct connection between the motor and the load (washing machine wave plate or inner tube), without the use of belts, gears, etc. Therefore, the direct drive refers to the driving method, which is a form of motor driving the load (direct drive, no transmission device). Imagine the classic scene of using a pen to turn the tape when you were young (pictured below). If you compare the pen to a motor that outputs power and the load is at hole A, it is a direct drive. The load is in the B hole, which is driven by a belt, which is non-direct drive.
The direct drive motor, that is, this pen, can choose any motor such as DC motor, AC motor, and ultrasonic motor. In the washing machine industry, DD direct drive motors are selected for torque servo motors, DD + torque servo motors, collectively referred to as DD direct drive motors.
There are many types of motors that can be matched with non-direct drive methods. The category has developed from non-frequency conversion to frequency conversion, and in frequency conversion, from AC frequency conversion to DC frequency conversion. The full name of BLDC is brushless dc motor, and the Chinese name is brushless dc motor. It is a type of DC variable frequency motor. It is also the most outstanding motor in non-direct drive. Everyone often mentions it.
So there will be such a statement, BLDC motor and DD direct drive motor, one is about the motor that drives the load, and the other is the way of driving the load. The point is not one thing that cannot be compared. It is true that in the electrical machinery industry, it is difficult to give an immediate judgment. After taking an inventory, you will find that each has its own advantages. What you need to consider when buying is in the application scenario, what kind of motor is needed, whether it needs a large output, or is it low noise? Do you care about the fast start or the high speed? These are the points we need to care about. Choose the motor that is not expensive and only buy the right one.
Although BLDC motor and DD direct drive motor, one is indirect drive and the other is direct drive. There is no good or bad driving method, but there are good or bad direct drive motors. To make the drum run at high speed, the direct drive motor must Very stable, safe, durable and precise.
Midea's new direct drive series are the first to see, the direct drive motor used is the fifth-generation DD direct drive that has undergone 4 iterations of innovation. The inefficient and unstable first-generation direct drive has been eliminated. The second-generation is too bulky and easy to demagnetize. The third-generation ordinary direct-drive coils have less precision and insufficient torque. The fourth-generation traditional direct-drive plastic shell is easy to damage, The failure rate is high.
Midea's fifth-generation direct drive motor uses a metal shell instead of a plastic shell, which is more stable and stable, anti-corrosion, deformation-proof and durable. Use PBT flame-retardant materials with high ignition point and safer, and use 9 holes to fix the motor and load, which is more stable and stable. The rotor core is used inside the motor, and the magnetic force is sufficient. The upgraded motor will run as usual for 20 years after testing, and the failure rate of the metal motor is low.
And in the silk soft washing process, the fifth-generation DD direct drive laundry decibel is only 45db, which is only slightly higher than 40db in the library environment. When the baby is asleep, the laundry will not disturb the TA. It is suitable for high noise requirements and quiet laundry. Don't disturb the family