基于混合储能的光储联合发电系统控制策略研究

发布时间：2018-02-13 01:36

本文关键词： 光伏发电混合储能低通滤波反馈调节能量控制　出处：《华北电力大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着社会的进步和经济的发展,人类面临越来越多的资源紧缺与环境污染问题。光伏发电是解决当今社会能源危机与环境危机的重要途径。光伏功率的随机性、波动性和间歇性对电网的安全、稳定运行带来了严重威胁。采用蓄电池与超级电容器混合储能的方式平抑光伏功率波动,克服了蓄电池寿命低,充放电效率差和超级电容器能量存储能力弱的缺点,对稳定光伏系统的输出,以及光伏发电系统的并网、运行具有重要的意义。因此,本文利用蓄电池与超级电容器混合储能的方式,接入光伏发电系统平抑光伏功率,并提出能量控制方法。为研究蓄电池与超级电容器混合储能的控制策略,采用三阶段充电方法对蓄电池充电特性进行实验研究,实验结果表明蓄电池在受极化效应影响下,恒流充电最高仅可充至60.97%。采用MATLAB/simulink仿真研究超级电容器充放电特性,仿真结果表明超级电容器不存在极化效应,其容量几乎可以完全利用。分析蓄电池、超级电容器单一储能方式与混合储能的优缺点,混合储能具有明显优势。根据长期光伏发电统计数据,提出了蓄电池与超级电容器的容量配置方案。采用混合储能在直流侧接入光伏系统的方式,提出了基于低通滤波的蓄电池、超级电容器分别平抑低频、高频功率波动控制算法及蓄电池与超级电容器协调控制方式;考虑蓄电池极化效应对其充电特性的影响,提出了基于蓄电池SOC反馈调节充放电滤波时间常数的控制算法,使蓄电池在较高与较低SOC时适当减少或增加出力,保证蓄电池更多地处于恒流充电状态即功率可控状态,延长蓄电池使用寿命。搭建光储联合发电系统实验平台对所提控制策略进行实验验证。结果表明,储能侧,蓄电池与超级电容器可分别以不同的控制周期平滑光伏功率波动,同时,当蓄电池SOC过高时,根据SOC反馈调节蓄电池滤波时间常数,可有效限制蓄电池出力,防止蓄电池过充;光伏侧,当光伏功率升高或突降时,混合储能可很好地补偿光伏功率缺额,对平抑光伏功率波动有显著作用。实验结果验证了本文所提控制策略的可行性。最后提出了光储联合发电系统能量控制方法,在以光伏发电、蓄电池、可控负荷、日常负荷及紧急备用电源柴油发电机组成的孤立系统中,能量控制方法根据光伏功率预测数据,制定系统中各组成部分的发电计划和用电计划,对光伏功率削峰填谷,保证系统稳定、经济地运行。算例分析验证了所提能量控制方法的正确性、可行性和经济性。
[Abstract]:With the progress of society and the development of economy, people are facing more and more problems of resource shortage and environmental pollution. Photovoltaic power generation is an important way to solve the energy crisis and environmental crisis. Volatility and intermittency pose a serious threat to the safety and stability of the power grid. The hybrid energy storage of batteries and supercapacitors is used to suppress the fluctuation of photovoltaic power and overcome the low battery life. The shortcomings of low efficiency of charge and discharge and weak energy storage capacity of supercapacitors are of great significance for stabilizing the output of photovoltaic system and grid connection of photovoltaic system. In this paper, the hybrid energy storage system of battery and supercapacitor is used to stabilize the photovoltaic power, and the energy control method is proposed to study the control strategy of the hybrid storage energy between battery and supercapacitor. The three-stage charging method is used to study the charging characteristics of the battery. The experimental results show that under the influence of polarization effect, the constant current charge can only be charged to 60.97. MATLAB/simulink simulation is used to study the charge-discharge characteristics of supercapacitors. The simulation results show that the supercapacitor has no polarization effect, and its capacity can almost be fully utilized. The advantages and disadvantages of storage battery, supercapacitor single energy storage mode and hybrid energy storage are analyzed. The hybrid energy storage has obvious advantages. According to the statistics of long-term photovoltaic power generation, the capacity configuration scheme of battery and supercapacitor is proposed. The hybrid energy storage energy is connected to the photovoltaic system at the DC side. A low pass filter based control algorithm for low frequency and high frequency power fluctuation of the supercapacitor and a coordinated control method between the battery and the supercapacitor are proposed, and the effect of the polarization effect of the battery on its charging characteristics is considered. This paper presents a control algorithm based on the feedback regulation of charge and discharge filter time constant of battery SOC, which can reduce or increase the output force of battery at higher and lower SOC, and ensure that the battery is in constant current charging state, that is, power controllable state. The experimental results show that the storage battery and the supercapacitor can smooth the photovoltaic power fluctuation with different control periods, and the proposed control strategy is verified by building the experimental platform of the optical storage combined generation system, the results show that the storage side, the storage battery and the supercapacitor can smooth the photovoltaic power fluctuation in different control periods. At the same time, when the SOC of the battery is too high, the filter time constant of the battery can be adjusted according to the feedback of SOC, which can effectively limit the output of the battery and prevent the battery from overcharging; on the photovoltaic side, when the photovoltaic power increases or drops suddenly, Hybrid energy storage can compensate photovoltaic power deficit very well and play a significant role in suppressing the fluctuation of photovoltaic power. The experimental results verify the feasibility of the control strategy proposed in this paper. Finally, the energy control method of optical storage combined generation system is proposed. In an isolated system composed of photovoltaic power generation, storage battery, controllable load, daily load and emergency standby diesel generator, the energy control method is based on the photovoltaic power prediction data. The generation plan and power consumption plan of each component of the system are worked out to cut the peak and fill the valley of the photovoltaic power, so as to ensure the stable and economical operation of the system. An example is given to verify the correctness, feasibility and economy of the proposed energy control method.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TM61

【参考文献】