releaseTime:2024-06-15 08:58:30source:Mu TiannumberOfPageViews:0
The principle of variable frequency speed regulation for electric hoists is mainly based on variable frequency speed regulation technology. It combines the relationship between motor speed and power input frequency, and achieves motor speed regulation by controlling the efficiency of motor power input, thereby controlling the operating speed of electric hoists. The following is a detailed explanation of the principle of variable frequency speed regulation for electric hoists:
The principle of variable frequency speed regulation technology:
Variable frequency speed regulation technology mainly controls the motor speed (n) by changing the power input frequency (f). The relationship between the speed (n) of the motor and the input frequency (f) of the working power supply, the motor slip rate (s), and the number of magnetic poles (p) of the motor can be expressed by the formula: n=60f (1-s)/p.
By adjusting the power input frequency, the motor speed can be controlled, thereby achieving control over the operating speed of the electric hoist.
The application characteristics of variable frequency speed regulation on electric hoists:
Compared to DC transmission schemes, variable frequency speed regulation technology does not require the use of complex, expensive, and maintenance troublesome DC motors, but instead selects convenient, energy-saving, and economical AC motors.
Compared with conventional electrical control schemes, the frequency conversion system eliminates components such as high-power resistors on the motor rotor side, acceleration contactors, and motor forward and reverse AC contactors, simplifying the system structure.
The acceleration and deceleration time of the motor can be adjusted to achieve soft start and soft stop of the system, with smooth speed changes, smooth operation, and stable low-speed performance.
It can meet the requirements of the lifting mechanism for speed regulation hardness, low-frequency torque characteristics, and four-quadrant operation, and can operate at low speed for a long time, effectively preventing the phenomenon of hook slipping in the air under heavy loads.
By adopting vector control closed-loop method, even at 0Hz, the lifting motor can output at rated torque, achieve zero speed holding brake, full speed control, and reduce vibration and wear of the holding brake when it is closed.
By using frequency conversion speed regulation technology, approximately 35% of motor energy consumption can be saved and the service life of the equipment can be extended.
Factors to consider in practical applications:
When selecting a frequency converter, it is necessary to choose the type of frequency converter reasonably based on the specific situation and requirements of the electric hoist speed control system, in order to meet the basic requirements and the high output capacity requirements of the motor.
The application of variable frequency speed regulation technology also needs to consider the coordination with PLC systems, and achieve more efficient and stable speed regulation control of electric hoists by optimizing control strategies.
The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist,Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment