通用瞬时功率定义及广义谐波理论

A UNIVERSAL DEFINITION OF INSTANTANEOUS POWER AND BROAD-SENSE HARMONIC THEORY

传统功率理论无法对非正弦电路中的功率现象加以解释 ,现有的瞬时功率理论的物理意义又都不够明确。针对这一问题 ,该文提出了一种基于最小传输能量损失的有功及无功功率定义 ,给出了数学模型及简化解。该定义物理意义明确 ,能够与传统正弦电路功率理论、弗兰芝 (Fryze)单相无功理论和赤木泰文 (H .Akagi)三相无功理论相统一。在该定义体系中 ,单相电路与三相电路的有功、无功确定原则是一致的。该文还提出了一种广义谐波理论 ,该理论所定义的谐波不仅具有传统的傅立叶谐波两两正交的优点 ,而且可以直观地衡量负载的非线性程度 ,并将谐波理论与本文所提功率理论相统一。

Traditional power theory can not be applied to circuits under nonsinusoidal conditions. The now available instantaneous power theories have no clear physical meanings. To solve these problems, this paper presents a definition of instantaneous power which is based on minimizing transmission loss. The mathematical model is given, and its simplified solution is presented. This definition has a distinct physical meaning. It is identical with the traditional power theory when applied to sinusoidal circuit, with Fryze's definition when applied to single phase circuit, and with H.Akagi's definition when applied to three wire three phase circuit. According to this definition, the determination of real and reactive power has a same criterion both in single phase circuit and 3 phase circuit. This paper also presents a broad sense harmonic theory, with which we can judge the non liner degree of the load. This harmonic theory can be unified with the above mentioned power theory.