voltage direction

例句：

1. 1.The voltage direction is critical for the safe operation of the power grid.
   电压方向对于电网的安全运行至关重要。
2. 2. The new device can accurately measure the voltage direction in real-time.
   这款新设备可以实时准确地测量电压方向。
3. 3.During the fault, the voltage direction changed rapidly.
   在故障期间，电压方向迅速变化。