The objective of this article is to propose a photovoltaic (PV) power and energy storage system with bidirectional power flow control and hybrid charging strategies. In order to optimize the battery charging performance, five charging strategies, including the constant-current charging, the pulse-ripple-current charging, the sinusoidal-ripple-current charging, the bidirectional pulse-ripple-current, and the bidirectional sinusoidal-ripple-current charging, are adopted. Traditionally, in order to realize these charging strategies, the PV charger should abandon the maximum power point tracking function to maintain the power flow balance. As a result, the output power of the PV array will be decreased. Therefore, bidirectional power flow control strategies are proposed to achieve the maximum PV power utilization as well as to realize the hybrid charging methods. In addition, with the proposed strategies, the bidirectional charging/discharging capability of the battery is able to achieve the maximum PV power utilization. All the proposed strategies can be realized by the digital signal processor without adding any additional circuit, component, and communication mechanism. Theoretical analysis and control principles will also be revealed. Finally, a 5-kW prototype circuit with both simulation and experimental results demonstrate the performance and feasibility of the proposed strategies.

中文翻译：

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三相光伏发电和储能系统的双向潮流控制和混合充电策略


本文的目的是提出一种具有双向潮流控制和混合充电策略的光伏（PV）发电和储能系统。为了优化电池充电性能，采用恒流充电、脉冲纹波充电、正弦纹波充电、双向脉冲纹波充电、双向正弦纹波充电五种充电策略-电流充电，均采用。传统上，为了实现这些充电策略，光伏充电器应放弃最大功率点跟踪功能以维持潮流平衡。结果，光伏阵列的输出功率将会降低。因此，提出了双向潮流控制策略，以实现最大的光伏发电利用率以及实现混合充电方法。此外，通过所提出的策略，电池的双向充电/放电能力能够实现最大的光伏发电利用率。所有提出的策略都可以通过数字信号处理器来实现，而无需添加任何额外的电路、组件和通信机制。理论分析和控制原理也将被揭示。最后，一个 5 kW 原型电路的仿真和实验结果证明了所提出策略的性能和可行性。