Since 2020, due to the impact of the new crown epidemic, the global economy has generally been in recession, and the home appliance industry has also been greatly affected. However, unexpectedly, the small home appliance market is extremely hot. Many small home appliance companies have full orders, and the performance of small home appliances and related companies has also risen sharply. As the core component of electric small household appliances, the market for AC universal motors has also developed rapidly. Compared with DC or induction motors, AC universal motors have the advantages of simple structure, mature technology, high power density, and high-cost performance. They are widely used in small household appliances. However, series motors have soft torque characteristics and the motor speed changes greatly with a load. , Poor speed regulation performance and other shortcomings, are subject to many restrictions in practical applications. Especially in some products such as multi-functional food processors, cook machines, multi-functional broken wall cooking machines, etc., only simple pressure reduction, tap speed adjustment, and other control methods can not meet the requirements. For this reason, the above-mentioned AC universal motor must be equipped with a powerful electronic speed control device to meet the performance requirements of the terminal product.

At present, the AC universal motor speed control mainly has the following methods:

1. Install a multi-pole magnetic ring on the motor rotor, and install a Hall sensor on the motor support. The Hall sensor converts the detected rotating magnetic field signal into a speed signal and sends it to the power controller.

2. Install a circular grating on the motor rotor, and install a grating sensor on the motor support. The sensor converts the optical signal that changes with the high frequency of the speed into a speed signal and sends it to the power controller.

3. The power supply controller controls the output voltage according to the principle of negative feedback regulation according to the speed signal to stabilize the motor speed within a certain accuracy range. The power controller is divided into two types: SCR speed regulation mode and PWM inverter control.

After the AC motor is equipped with the above negative feedback speed control device, the performance can be greatly improved. The speed adjustment range can be from tens to tens of thousands of revolutions, the speed changes smoothly, and realized the real step-less speed change. At the same time, negative feedback control can limit the high speed at no-load, greatly reduce product noise, and reduce motor sparks. Moreover, the negative feedback function can make the motor automatically adjust the current according to the load at low speed, and the motor torque characteristic hardness is greatly improved, which solves the problem of The excitation motor speed fluctuates greatly, and the low gear torque is insufficient.

With the rapid development of today's power electronics technology, various control semiconductor devices the SCR, the maturing control MOSFET, BJT, IGBT, GTO or the like, and the development of PWM, negative feedback control of the inverter power supply has been widely used, mature technology. Compared brushless DC motor, although the negative feedback universal motor have  a  certain gap in performance, but its more cheaper, cost effective ,and widely used, such as a washing machine, broken machines, kitchen robots and other products used in most They are all universal motors with negative feedback.

In summary, the series motor with negative speed feedback function has superior performance. Power Motor has a wealth of product lines and solutions for such products, which can provide customers with the best technical route. For more information, please contact sales engineer 400-622-3329.

Typical product data is as follows:

Motor model: series of 76#, 80#, 88#, 95#, 98#, etc.

Power: 500-1200W

Speed: 100-25000RPM

 Rated voltage: 120-230V/AC

Speed accuracy: ±2%

Response time: <100mS