First of all, current detection method for three-phase four-wire system is researched.

首先，本文针对三相四线制的电流检测方法进行了研究。

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The neutral voltage of the three-phase four-leg inverter employed in UPS is desired to be very low.

当三相四桥臂逆变器用于UPS时，要求其中线电压很低。

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A new DSP based hybrid power filter designed under the condition of three-phase four-wire system is presented.

介绍了一种基于DSP的三相四线制系统混合型电力滤波装置。

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For the first time the W.H.O.raised its alert level from phase four to phase five on April twenty-ninth.

VOA: special.2009.05.06

The classical hoplite formation then was not the long lived military institution of scholarly tradition, but merely one phase in a history of almost four centuries of slow change towards ever denser and more cohesive heavy infantry formations."

这种方阵的形成,并不是经过长期传承的传统军事制度,只是步兵阵型演变的一个阶段,战阵逐渐向更加紧密坚固的步兵阵型转化,而这个变化持续了约有四个世纪"

耶鲁公开课 - 古希腊历史简介课程节选

Phase four means that a virus has gained the ability to cause community-level outbreaks.

VOA: special.2009.05.06

And then, Phase Four: We will dominate Sunday afternoons, Monday nights, Sunday nights and some Thursday nights of our choosing.

FORBES: Baltimore Ravens Scheduling Snafu Highlights NFL's Arrogance

England were trounced 36-0 by the Springboks when the teams met in the pool phase four weeks ago -- but Ashton believes it was probably the best thing that could have happened!

CNN: England ready to shock Springboks

Muscle activation: This phase involves four-second contractions of major muscle groups in the lower body, including calves, quadriceps, hamstrings, hip flexors, groin, and hip and lower back muscles to help athletes increase awareness of individual muscle groups.

CNN: How do I protect my daughters' knees from sports injuries?