光储一体化并联系统优化控制设计分析
DESIGN AND ANALYSIS FOR OPTIMAL CONTROL OF INTEGRATED WITH PHOTOVOLTAIC AND ENERGY STORAGE PARALLEL SYSTEM
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摘要: 光储一体化并联系统由于具有高度电力电子化的特点,当母线电压波动时,大量电力电子装置使系统抗扰动能力减弱。该文首先采用一种考虑母线电压变化率的自适应下垂控制策略,减小系统的电压波动,增强系统运行稳定性;然后建立含有下垂控制的光储一体化并联系统的状态空间模型,分析下垂系数对系统稳定性的影响,并在此基础上得到自适应下垂系数的优化控制取值范围,提升系统的电压稳定性。最后,通过仿真与实验证明该文所采用的自适应下垂控制策略不但可减小下垂控制所带来的电压偏差,还可缩短电压突变之后的恢复时间,提高系统的稳定性。Abstract: Due to the integrated with photovoltaic and energy storage parallel system has the characteristics of high power electronic,the stability and operation flexibility of the DC microgrid formed by it are different from the traditional AC grid. Among them,a large number of power electronic devices bring weakened anti-disturbance capability to the system,and the bus voltage is prone to fluctuate and cause the problem of instability of the entire system. To this end,this paper first adopts an adaptive droop control strategy that considers the rate of change of the bus voltage to reduce the system voltage fluctuations and enhance the system’s operating stability.Then establishes a state space model of the integrated with photovoltaic and energy storage parallel system with droop control The influence of the droop coefficient on the system stability is analyzed. On this basis,the optimal control value range of the adaptive droop coefficient is obtained to improve the voltage stability of the system. Finally,the simulation and experimental results show that the adaptive droop control strategy adopted in this paper can not only reduce the voltage deviation caused by the traditional droop control,but also shorten the recovery time after the sudden voltage change and improve the stability of the system.