基于pq分解的瞬时无功电流与功率分析新方法  

A New Instantaneous Reactive Current and Power Analysis Based on pq Decomposing

作　　者：刘金华[1] 刘永强[2] 

机构地区：[1]电子科技大学中山学院,广东中山528403 [2]华南理工大学电力学院,广州510640

出　　处：《电测与仪表》2009年第5期41-45,共5页Electrical Measurement & Instrumentation

摘　　要：如何定义三相系统的瞬时无功电流、瞬时无功功率一直是学术界关心的问题。本文从电力系统对无功考核的角度出发,详细讨论了各瞬时电流、瞬时无功功率的特性,将电流分解为p、q轴分量(本文设定电压向量[ua,ub,uc]T落在p轴上),从而得到p、q轴的功率。指出p轴电流除有功电流ip外还含有瞬时无功电流ip2,由此指出瞬时无功功率由q轴瞬时无功功率和p轴瞬时无功功率构成。当零序电压不存在时,p轴瞬时无功不存在,q轴瞬时无功表示相间负载交换的功率;若再设零序电流也不存在则此时的瞬时无功就是Akagi定义的瞬时无功功率。How to define instantaneous reactive current and reactive power in three-phase non-sinusoidal asymmetrical systems is still a concerned problem by academia. From the view of assessing reactive power in power system, this paper discusses the properties of the instantaneous current and instantaneous reactive power in detail. By decomposing instantaneous current into p-axis and q-axis components （The voltage vector [ua,ub,uc]^T is regarded to be located at p-axis）, then the corresponding reactive power of p-axis and q-axis is given, and point that the current of p-axis contains instantaneous reactive current component ip2 except active current ip. So the instantaneous reactive power is composed of q-axis and p-axis instantaneous reactive power. And if zero sequence voltage doesn＇t exist, then p-axis instantaneous reactive power doesn＇t exist, and q-axis instantaneous reactive power denotes the power between phase loads. Furthermore, if zero sequence current is also zero, then the instantaneous reactive power is just the instantaneous reactive power defined by Akagi.

关 键 词：瞬时无功功率 瞬时无功电流 三相不对称非正弦系统 谐波 

分 类 号：TM76[电气工程—电力系统及自动化]