Why use frequency converters?

Editor:浙江汇迅骏机电技术有限公司 │ Release Time:2021-07-14 


Controls the starting current of the motor

When the motor starts directly through the power frequency, it will produce 7 to 8 times the rated current of the motor. This current value will greatly increase the electrical stress of the motor windings and generate heat, thus reducing the life of the motor.  And frequency conversion speed regulation can be at zero speed zero voltage start (can also be appropriate to add torque).

 

Reduce power line voltage fluctuation

When the power frequency of the motor starts, the current increases sharply while the voltage also fluctuates greatly. The voltage drop depends on the power of the motor and the capacity of the distribution network. 

 

Less power is required to start

Motor power is proportional to the product of current and voltage, so the power consumed by the motor starting directly through the power frequency will be much higher than the power required by the variable frequency starting. 

 

Controlled acceleration

Frequency conversion speed control can start at zero speed and accelerate evenly according to the user's needs, and its acceleration curve can also be selected (linear acceleration, S-shaped acceleration or automatic acceleration).  And through the power frequency start of the motor or connected mechanical parts of the shaft or gear will produce violent vibration.

 

Adjustable running speed

The use of frequency conversion speed regulation can optimize the process, and can change rapidly according to the process, but also through the remote control PLC or other controllers to achieve speed change. 

 

Adjustable torque limit

Through frequency conversion speed regulation, can set the corresponding torque limit to protect machinery from damage, so as to ensure the continuity of the process and product reliability. 

 

Controlled stop mode

As controllable speed, in the frequency control of motor speed, stop mode can be controlled, and there are different ways of stopping can choose (slow parking, free parking, and stop + dc brake), also it can reduce the impact on the mechanical parts and motor, which makes the system more reliable, life will also be increased accordingly. 

 

Energy conservation

Centrifugal fans or pumps using frequency converters can greatly reduce energy consumption, which has been reflected in more than ten years of engineering experience.  Since the final energy consumption is proportional to the speed of the motor, the return on investment is faster with frequency conversion. 

 

Reversible operation control

In frequency converter control, to achieve reversible operation control without additional reversible control device, only need to change the phase sequence of output voltage, so as to reduce maintenance cost and save installation space. 

 

Reduce mechanical moving parts

Because the current vector control inverter and synchronous motor can achieve efficient torque output, so as to save gear box and other mechanical transmission parts, the final composition of direct frequency conversion drive system. This reduces costs and space and improves stability.