三相负载功率测量实验现象解析

摘要

In the course of circuit analysis,the measurement experiment of three phase load power is one of the most important and difficult experiments in actual application.In the process of this experiment,it is found that the result is far away from the theoretical analysis.Given the invariable source voltage,the total power of Delta connection is not the triple size of star connection when we use the same resistive load.This cannot be explained by regular error analysis.So,we look into the V-I characteristic of the resistant.We have found that the V-I characteristic of electric incandescent lamp is nonlinearity.All these could explain the rea-son of big error.So we prove that the electrical theory is correct.%“电路分析”课程中，三相功率的测量实验是实际应用的重要实验，也是个难点。在实验过程中发现，实验结果和理论分析有很大差别，当电源电压不变时，同样的电阻性负载做三角形连接的总功率不是星形连接的3倍。对此，从负载的伏安特性入手，通过实验得到白炽灯的伏安特性是非线性的，从而说明了产生过大误差的原因，验证了电工理论的正确性。