摘要
基于虚拟同步发电机控制的光储单元在电力系统中的比重逐步增加,多光储单元之间的不同特性导致其同时运行时存在一定的协同配合问题,为较好实现基于虚拟惯性控制的多光储单元协同运行,文章提出一种对各单元虚拟惯量进行灵活调节的多光储单元协同控制策略。首先,通过高通滤波和滑动滤波对系统中的功率扰动进行频次区分,高频扰动时,优先选择超级电容器提供惯性支撑,超级电容容量不足时,通过虚拟惯量的协同调节使蓄电池和超级电容协调出力,并根据荷电状态差异分配各蓄电池端出力。低频扰动时选择蓄电池提供所需惯性支撑,考虑蓄电池之间的荷电状态差异与各个换流器的容量差异,引入模糊控制,在防止蓄电池过充过放和保护换流器安全运行的基础上,合理分配低频扰动时系统所需的惯性支撑,实现各储能端的安全运行与系统的频率稳定。同时,建立多端系统小信号模型,利用根轨迹法分析主要控制参数对系统稳定性的影响。最后,通过硬件在环实验平台验证所提协调控制策略的有效性与优越性。
The proportion of the optical storage units based on virtual synchronous generator control in the power system has been gradually increasing.The different characteristics between the multiple optical storage units lead to certain coordination problems when they are running at the same time.For better implementation of virtual inertial control based on the optical storage units working together,this paper proposes a multi-optical storage unit cooperative control strategy that flexibly adjusts the virtual inertia of each unit.First of all,the power disturbances in the system is differentiated by the high-pass filtering and the sliding filtering waves.On the one hand,when there appear high-frequency disturbances,the supercapacitor is preferred to provide inertial support.When the capacity of the supercapacitor is insufficient,the storage battery and the supercapacitor are coordinated through coordinated adjustment of the virtual inertia.The output of each battery is distributed according to the differences in state of charge.On the other hand,the batteries are selected to provide the required inertial support when low-frequency disturbances occur.Considering the differences in the state of charge between the batteries and the capacity differences of the converters,a fuzzy control is introduced.On the basis of preventing the batteries from overcharging or discharging and protecting the safe operation of the converters,the fuzzy control can reasonably allocate the inertial support required by the system during the low-frequency disturbances so as to achieve the safe operation of each energy storage end and the system frequency stability.At the same time,a small-signal model of the multi-terminal system is established,which analyzes the influence of the main control parameters on the system stability using the root locus method.Finally,the effectiveness and superiority of the proposed coordinated control strategy are verified by the hardware-in-the-loop experimental platform.
作者
孟建辉
赵彭辉
王毅
张赟
MENG Jianhui;ZHAO Penghui;WANG Yi;ZHANG Yun(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Baoding 071003,Hebei Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2021年第5期1921-1931,共11页
Power System Technology
基金
国家自然科学基金资助项目(51807064)
河北省自然科学基金资助项目(E2018502152)
中央高校基本科研业务费专项资金资助项目(2019MS074)。
关键词
混合储能
虚拟惯性
分频控制
协同运行
荷电状态
模糊控制
hybrid energy storage
virtual inertia
frequency division control
cooperative operation
state of charge
fuzzy control
