基于直流电压信号的光储系统协调控制策略

在以光伏系统、储能装置、并网逆变器、交直流负荷构成的光储系统基础上,分别对离网和并网两种运行方式的控制策略展开研究。考虑到光伏装置的随机性、储能装置的充放电属性和负载多变的现象提出直流侧电压分层控制方式。以直流电压幅值为依据,协调储能装置自适应下垂控制,同时网侧双向变流器采用虚拟同步发电技术,能较好地稳定直流侧电压,降低系统内部功率冲突,保证内部功率交换的稳定。最后通过MATLAB/Simulink在离/并网模式下,分别仿真验证系统协调控制策略的有效性。仿真结果表明:在离网模式下,与下垂控制进行对比,虚拟同步技术的引入使得系统具有较强的鲁棒性;协调控制策略保证了系统稳定并实现储能装置的有效利用。

Coordination Control Strategy of Photovoltaic Energy Storage System Based on DC Voltage Signal

Based on the optical storage system composed of photovoltaic system, energy storage device, grid-connected inverter and AC/DC load, it has researched on the control strategies of run modes including off-grid and grid connection, respectively. Considering the randomness of photovoltaic devices, the charging and discharging properties of energy storage devices and the phenomenon of variable load, the DC side voltage layered control mode was proposed. On the basis of the DC voltage amplitude with coordination of adaptive droop control for energy storage devices, at the same time, the grid-side bidirectional converter adopts virtual synchronous power generation technology so that DC side voltage can be more stable to reduce internal power conflicts and ensure the stability of internal power exchange. Finally, through MATLAB/Simulink being in off/connected mode, the effectiveness of coordinated control strategy was verified separately by simulation. The simulation results show that: in off-grid mode, compared to the droop control, the introduction of virtual synchronization has increased robustness of the system. The coordinated control strategy has ensured the stability of the system and realized the effective utilization of the energy storage device.