And to make matters worse for the pilot, as the tips of the rotor blades approach the speed of sound (around 1,200kph at lower altitude temperatures), shock waves produce huge vibrations.

这种情况对飞行员来说很糟，因为螺旋桨的尖部接近声速(在海拔较低的温度下大约1200kph)，冲击波造成强烈震动。

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Having three "waves" of magnetism induced in the rotor with every revolution, instead of just one, smooths out the induction process and allows more torque to be generated.

由于每次旋转过程转子都有三“波”感生磁场，而不是只有一“波”，其感应过程更平滑而使其能够产生更大的扭矩。

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Voltage waves are deduces on lower bridge arm PWM modulation and theory of rotor position detection based on EMF is introduced.

分析了下桥臂调制方式下绕组端电压波形，并基于此介绍了反电势法检测转子位置原理。

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