三相不平衡对电网的影响及解决方法

Research on the influence of three-phase unbalance on power grid and its solution

针对目前农网和城网中普遍存在的三相不平衡问题,深入研究配电台区三相不平衡治理的运行特点及各项指标,给出了3种常用的三相不平衡治理方案,包括换相开关型三相负荷自动调节装置、电容型三相负荷自动调节装置、电力电子型三相负荷自动调节装置.这3种解决方案根据不同的补偿原理,从负荷侧或者电源侧补偿了三相不平衡电流,都分别实现了负荷平衡化补偿的目的.通过详细分析3种补偿装置的工作原理、治理效果、优缺点及应用前景,以及对补偿装置进行仿真,证明了3种治理方法的有效性和可靠性,其结果能够很好地指导相关的研究与应用工作.

In view of the current three-phase unbalanced problems in the agricultural and urban networks,the operation characteristics and various indexes of the three-phase unbalance control in the radio distribution area are studied.Three kinds of common three-phase unbalance treatment schemes are proposed,including the phase switch type three-phase load automatic regulation device,the capacitive three-phase load automatic regulation device,and electronic three-phase load automatic regulation device.According to the different compensation principles,the three solutions compensate for the unbalanced three-phase current from the load side or the power side,and the purpose of load balancing compensation is achieved respectively.Through the detailed analysis of the working principle,the effect,the advantages and disadvantages and the application prospect of the three compensation devices,and the simulation of the compensation device,the validity and reliability of the three methods are proved,and the results can guide the related research and application work well.