conversion formula的用法和样例：
例句
- He is good at rapid calculation, and can immediately tell the answer of an arithmetic formula on seeing it.
他的速算能力很强，看过算式后，得数就能脱口而出。 - The rotor current formula of this kind of generator is deduced when considering the stator harmonic stationary magnetomotive force with very simple method in this paper.
在考虑了定子高次谐波恒定磁势作用的情况下，用极为简便的方法推导出符合实际的转子的电流计算式。
