不对称冲击负荷产生的电压波动计算方法探讨

Discussion on the Calculation Method of Voltage Fluctuation Caused by Asymmetric Impact Load

电气化铁路冲击负荷具有不对称的特性,无法直接用基于三相对称系统的仿真软件计算其在电力系统公共连接点产生的电压波动。为解决这一问题,根据电压波动定义及计算公式原理,结合星形接线和三角形接线形式下相电压与线电压的关系,论证了相电压和线电压波动的一致性,并由此提出了等效负荷的概念。仿真计算结果表明,利用等效负荷在三相对称仿真系统中计算的结果与不对称冲击负荷最大相产生的电压波动相等。从而从理论和实例两方面证明了等效负荷在不对称冲击负荷电压波动计算中的适用性。

The impact load of electric railway has the characteristics of asymmetric, and the voltage fluctuation it caused cannot be calculated based on the of simulation software of three-phase symmetric power system. In order to solve this problem, the relationship between the phase voltage and line voltage in the form of star connection and triangle connection is presented according to the definition of voltage fluctuation and calculation formula. The simulation results show that the equivalent load is equal to the voltage fluctuation caused by the asymmetric impact load in the three-phase symmetric simulation system. The applicability of the equivalent load in the calculation of the voltage fluctuation of the asymmetric impact load is demonstrated through theory and examples.