Brushless DC Magnetic Pump VS Traditional Brush Pump

2016-09-07

Through magnetic drive technology, brushless magnetic pump realized non-contact torque transmission, thus displacing dynamic sealing by static sealing, which successfully solves the leakage problem, eliminates potential safety risk of inflammable & explosive & poisonous liquid leakage, and effectively guarantees the safety production and workers’ health. 

How brushless DC pump works? 
Firstly, we should have an overview about the structure of brushless DC Magnetic pump. Unlike the brush pump, brushless pump is driven by magnetism. The impeller and permanent magnet are molding from one complete injection mold, which makes up the pump rotor. The high-performance ceramic shaft is fixed in the pump housing through the rotor. Between stator and rotor, there is a thin layer of isolation. 
So there is no traditional mechanical shaft seal, and the whole pump is completely sealed.
 

 
When the stator coils energize with electricity, magnetic field comes over and it drives permanent magnets rotor to run. After magnetizing, there will be an intact coupling magnetic system. The magnetic energy will reach the minimum when magnetic pole of stator coils is in opposite to magnetic pole of rotor, that is, the displacement angle of two magnetic poles Φ=0. And it will reach the maximum when magnetic pole of stator coils is the same polar with magnetic pole of rotor, that is, the displacement angle of two magnetic poles Φ=2π/n. Removing the external forces, due to the magnet poles mutually repel each other, magnetism will recover to the lowest state. 

Brushless motor adopts electronic components for reversing, instead of carbon brush. Both the rotor and stator have multipolar magnetic fields. The pole orientation will automatically alter when rotor rotate a certain angle relative to stator. This way, the rotor will always keep polar repulsion. So, brushless magnetic pump has higher revolving speed and high efficiency. 

Besides, the trick of operation in BLDC motors is the Hall sensor that is attached to the stator. It faces the magnets perpendicularly and can distinguish if the North or South pole is in front of it. 
When the Hall sensor senses the South pole, it keeps the coils turned off. When the sensor senses no magnetic field (or could be also the South pole), then it turns on the coils. The coils have both the same magnetic polarity which is North. So they pull the opposite pole and torque is then created.

If you put a probe to the Hall sensor and watch the signal, then you will discover that during a full rotation of the rotor, the Hall sensor is two times HIGH and two times LOW. The waveform on oscilloscope would be like this one:



Advantages compared with brush motor:

1. Leak-tightness: Pump shaft adopts closed static sealing instead of dynamic sealing; pump stator and rotor are completely isolated from each other; and epoxy resin is poured between stator and circuit board. These design let the pump completely avoid media leakage. Submersible also can be customized, which will be 100% waterproof.
2. Low energy consumption: Brushless motor is lower power consumption and high efficiency. Without independent lubrication and cooling water, it reduces energy consumption. 
3. Long life span: Brushless motor adopts electronic components for reversing, instead of carbon brush. The rotor adopts permanent magnet, and pump body uses environmental protection material. Combined with high performance steel shaft and shaft sleeve, and the sleeve and rotor are integrated into one injection mould to avoid abrasion, pump lifetime largely increased. 
4. Low vibration: With damping effect, it can reduce the effect of motor vibration and gas etching vibration on pump. 
5. Low noise: The noise can be as low as 25dB. 
6. Through adjusting the stator winder, brushless motor pump can achieve various parameters that clients need. Wide voltage operation also can be realized. 
7. When overloaded, pump rotor will automatically slip on the ceramic shaft to protect motor and pump. 


Application:

Brushless magnetic DC pump can be widely used in computer water cooling system, fountain, coffee machine, drinking machine, infusing tea machine, hydroponics, shower, water toothpick, hot water heater, hot water mattress, swimming pool water circulation, massage bathtub, car cooling circulation system, humidifier, air-conditioner, washing machine, medical apparatus and instruments, sanitary products, etc. 

TOPSFLO Brushless DC  Pump TL-B Series http://www.topsflo.com/brushless-dc-pump/
TOPSFLO Brushless DC  Pump TL-C Series http://www.topsflo.com/dc-brushless-pump/

Keywords:  brushless DC pump,brushless DC Magnetic pump,BLDC motor pump,water cooling system pump