These method can be described below: directly withdraw annex rotates , withdraw annex rotates by ramp ,current memory by using two speed controller.

• 通过对动态速降的研究,提出了几种解决动态速降的方法,分别是附加速度直接去掉法、附加速度斜率去掉法、用速度环双调节器的电流记忆法。