What are the quality performance indicators of the vfd?
1. How much starting torque can vfd output at 0.5HZ? The better vfd can output 200% high starting torque at 0.5HZ and below 22KW, and can output 180% starting torque above 30KW.
2. How long can the speed adjustment range control accuracy be, and how much torque control accuracy can be achieved? The high-performance vfd has a speed control accuracy of ±0.005% and a torque control accuracy of ±3%.
3. Pulse condition at low speed. The high-quality vfd has a speed pulse of only 1.5r/min at 1HZ.
4. Noise and harmonic interference. Noise and harmonic interference are important criteria for measuring a vfd. The modulation frequency of IGBT and IPM devices is higher than that of GTO and GTR. Although higher harmonics are always present, if the control method is better, some harmonics can be reduced.
5. Heat. The vfd generates a large amount of heat, which proves that the power consumption is large, the efficiency is low, the ventilation and heat dissipation system is not good, and the life of the vfd is affected accordingly.