EC blower due to the need to eliminate the use of the c […]
EC blower due to the need to eliminate the use of the collector ring and brush, the structure greatly simplified. At the same time not only improve the motor process, and the mechanical reliability of the motor running greatly enhanced life expectancy. At the same time, the air gap magnetic density can be greatly improved, the motor index can achieve the best design, the direct effect is the motor volume reduction, weight reduction. Not only that, but also has excellent control performance compared to other motors.
At present, large-capacity EC blower air flow adjustment has been a lot of frequency control mode, this type of inverter is mainly dependent on imports, expensive. At present, the power rating of 1kw below the fan, especially the home air conditioner and other fans have permanent magnet brushless DC motor drive, and the use of speed regulation mode. 1 ~ 10kw power range of the huge amount of fan, the basic use of induction motor drive, and adjust the air opening way to adjust the air volume. For this power range of the fan, the use of permanent magnet brushless DC motor drive to replace the original induction motor drive has great advantages.
EC blower because of the use of permanent magnet excitation, eliminating the induction motor excitation current loss; the same time permanent magnet brushless DC motor work in synchronous operation mode, eliminating the induction motor rotor core frequency loss. These two aspects of the permanent magnet brushless DC motor operating efficiency is much higher than the induction motor, small-capacity motor efficiency is more obvious.
EC blower requires rectangular wave current, the inverter running current rating refers to the peak of this rectangular wave. Induction motors require sine wave current, the current rating of the inverter running continuously refers to the effective value of this sine wave. In order to maintain the inverter on the motor current control capability, inverter DC voltage and motor induced electromotive force should have enough difference between. So brushless DC motor trapezoidal wave induced electromotive force and induction motor sine wave induced electromotive force can reach the peak voltage are limited by the inverter DC voltage. In this case, assuming that the peak of the brushless DC motor and the induced motor current is equal, the former power output is 33% higher than the latter.