The model test tried on this system did not use the tachometer generator but used rotor electromotive force instead to form the speed negative feed-back system.

本绕线式电动机转子电路脉冲调速系统模拟试验，省去了测速发电机，而利用转子电势组成速度负反馈系统。

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This creates a self-sustaining negative feed back loop as prices fall, produces cut back production, creating more unemployment, reducing demand, which increase deflationary pressures.

FORBES: American Political Economy Alters English Language