Ln = Natural Logarithm 自然对数
就是这个:
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例如:Nameplate output标称输出功率为40W
则:Ln(40)=3.68887945411393630285245569760072
0.09*3.68887945411393630285245569760072+0.49=0.821999150870254267256721012784065
结果为效率要大于82.2%