四线电路

一种新型双开关三相四线PFC电路的研究

Research on Novel Dual Switch 3-phase 4-line PFC Circuit

指出只要三相电压、电流对称，无论电压是否有畸变，在三相四线制电路中用p-q-r法检测系统的谐波电流时，ip，iq中只含有3k次谐波（k为整数）。

This article indicates that ip and iq only contains 3k harmonic ( k is a integer ) when p-q-r is used in harmonic detection of three-phase four-line system whenever the voltage is distorted or not with the premises that both voltage and circuit are balanced .

三相四线制电路中的瞬时无功功率及有源电力滤波器

Instantaneous Reactive Power and Active Power Filter in Three-phase Four-wire System

进行三相四线制电路的无功计量建模和实验研究。

Builded model and did experiment about the reactive energy metering of three-phase four-wire circuit .

为解决在三相四线制电路中使用有源电力滤波器滤除非线性负载的谐波问题，提出采用零线电流分离法来实现有源电力滤波器在三相四线制系统中的应用。

An active power filter is introduced for a three phase four wire system . The method of separating neutral wire current is used in this system .

新型四线制测温电路的研究

The new type of 4-wire circuit for measuring temperature with Pt 100

首先介绍了现有教材中已给出的三相电路功率的测量方法，进而提出了三相四线制三相电路功率测量的另三种接线方法。

Firstly , the existing methods of the three phase power measurement in the teaching materials are introduced . And then another three connection methods are suggested for three phase four wire circuits .

给出了利用运算放大器设计的电子二/四线转换器的电路形式，分析了电路性能，对两种实际设计电路进行了性能测试，给出了实验结果曲线。

A mode of circuits of electronic 2 / 4 converter designed using operational amplifiers is given . The performances of circuits are analyzed . The performance tests and experimental results of two practical circuits which are designed on one 's own are given separately .

该文提出了一种三相四线并联APF主电路统一的拓扑结构，建立了它的数学模型和性能指标体系。

This paper propose a unified main circuit topology of three-phase four-wire shunt APF , as well as its mathematic model and performance index system .

GB/T7624-1987在四线租用电话型电路上使用的标准化2400比特/秒调制解调器

2400 bits per second modem standardized for use on 4 wire leased telephone type circuits