When the locomotive is traveling at a constant speed or idling, the battery rather than the diesel engine can power the motor.

当火车头在相对恒定速度下前进或者空转时，这时电池就为马达提供能量，柴油发动机不工作。

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Constant speed drive, a hydro-mechanical component for changing variable engine gearbox speed to constant speed to drive the electrical power.

恒速驱动装置，将发动机齿轮箱的可变转速转变为恒速以驱动电源的液压机械式部件。

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At the same time, constant engine speed stabilizes output displacement of hydraulic pump and then stabilizes travel speed and vibratory frequency in turn, so that compaction quality is increased.

同时，发动机转速的恒定也使液压泵输出排量稳定，进而保证了行走速度和振动频率的稳定，提高了压实质量。

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