脉冲负载对独立电力系统运行特性影响

Influence of pulse load on operation characteristics of independent power system

脉冲负载工作模式复杂,对于容量和惯性有限的船舶电网等独立电力系统的冲击和影响较大。为研究脉冲负载下独立电网运行特性以及脉冲负载不同参数对独立电网运行特性影响,通过在Matlab/Simulink平台建立柴油发电机组-整流器-脉冲负载模型,在仿真的基础上研究分析脉冲负载峰值功率、占空比、周期以及前端滤波电容参数对电力系统动态特性的影响规律。本文算例结果表明,脉冲负载工作时会对独立电网引起电力系统各参数的周期性波动,且波动程度与脉冲负载的工作模式有关:当峰值功率增大时,柴油发电机组的调压效果受到影响而频率近乎不变;当占空比D=0.5时,电力系统电压波动最大;周期增大时对励磁调压系统的影响变大且频率受脉冲负载的影响变大;同时合理增大滤波电容可以平抑脉冲负载引起的功率冲击。

The work mode of pulse load is complicated,and the impact and influence on independent power system such as ship power grid with limited capacity and inertia are great.In order to study the independent power system operation characteristics under pulse load and the different parameters of pulse load on the influence of the independent power system dynamic characteristics,the model of diesel generator set-rectifier-pulse load is established based on the Matlab/Simulink platform.Through the simulation test,the influence of peak power,duty ratio,working cycle and front-end filter capacitor parameters of the pulse load on the dynamic characteristics of the power system is analyzed.The results show that pulse load causes periodic fluctuation of power system parameters,and the degree of fluctuation is related to the working mode of pulse load.When the peak power increases,the voltage regulation effect of the diesel generator set is affected,but the frequency is almost unchanged.If the duty cycle D is equal to 0.5,fluctuation of the voltage is the largest.When the period increases,the influence on the excitation voltage regulation system becomes greater and the frequency will be influenced more significantly larger by the pulse load.At the same time,reasonable increase of filter capacitance can suppress the power shock caused by pulse load.