有功功率测量误差分析
Analysis of Active Power Measurement Error
Abstract
用对称分量分析了三序功率与三相功率间的关系,得出三相功率是同一相序的电压与电流的对称分量函数;三相电路平衡时,用两瓦法能正确测量三相三线电路功率,当三相四线电路不平衡时,用两瓦法测量功率存在误差。 Using symmetrical components,this paper analyzes the relationship between 3-sequence power and 3-phase power and concludes that 3-phase power is a function of the symmetrical components of voltages and currents of the same phase sequence.When the 3-phase circuit is in a balanced condition,we can correctly measure the power of the 3-phase 3-wire circuit in the 2-bush method.If the 3-phase 4-wire circuit is not balanced,there might be errors with the power measurement in the 2-bush method.