基于Markov链光伏储能模型的传输功率可用性评估

Power transfer availability evaluation based on Markov chain photovoltaic energy storage model

为了量化光伏发电传输功率的可用性,文章基于光伏储能系统能量状态的Markov链,建立了光伏组件与储能系统之间能量传递过程模型,并采用蒙特卡洛方法,根据实际太阳光入射功率和负荷分布的概率密度函数,生成日间光伏功率和负荷的随机值;再根据二者的差值直方图得到转移概率、一步转移概率矩阵和极限概率,建立了不同尺寸储能装置的储能容量与传输功率可用性的关系。此外,对不同工作温度引起的电池容量下降进行了可用性影响研究,结果表明,温度影响电池充放电效率,从而影响储能容量,并通过数值计算得到了不同储能装置效率下储能容量与传输功率可用性之间的关系。该模型也适用于储能装置老化导致的储能容量降低的情况。

In order to quantify the availability of transmission power of photovoltaic power generation, based on the Markov chain of energy state of photovoltaic energy storage system, the model of energy transfer process between photovoltaic module and energy storage system is established, and the random values of daytime photovoltaic power and load are generated by Monte Carlo method according to the probability density function of actual sunlight incident power and load distribution, Then the transfer probability is obtained according to the difference histogram,the one-step transfer probability matrix and limit probability are obtained, and the relationship between the energy storage capacity and the availability of transmission power of energy storage devices with different sizes is established. In addition, the availability impact of battery capacity decline caused by different working temperatures is studied. The results show that the temperature affects the battery charge and discharge efficiency, thus affecting the energy storage capacity.Through numerical calculation, the relationship between the energy storage capacity and the availability of transmission power under different energy storage device efficiency is obtained.Therefore, the model is also applicable to the reduction of energy storage capacity due to the aging of energy storage devices.