频率f(Hz) 转速N% 流量O% 扬程H% 轴功率P% 节电率
50 100% 100% 100% 100% 00%
45 90% 90% 81% 9% 10%
40 80% 80% 64% 2% 80%
35 70% 70% 49% 3% 70%
30 60% 60% 36% 6% 40%
25 50% 50% 25% 5% 5%
根据上述原理可知改变风机的转速就可改变风机的功率。
例如:将供电频率由50Hz降为45Hz,
则P45/P50=453/503=0.729,
即P45=0.729P50将供电频率由50 Hz降为40Hz,
则P40/P50=403/503=0.512,即P40=0.512P50