在面对电网故障导致的电压跌落时，为解决构网型储能变流器在低电压穿越时的电流越限和电压支撑能力有限问题，提出了一种计及低电压穿越电流限幅策略的虚拟同步发电机（VSG）与静止无功发生器（SVG）混合系统无功协调控制方法。首先，介绍了VSG的典型控制策略，并对其在不同程度电网电压跌落下的暂态特性功角曲线进行分析；随后，对已有的q轴优先限流策略加以改进，根据d轴电流减小值等比例减小有功功率参考值，得到了有功参考自适应的q轴优先限流策略，可以提升VSG的功角稳定性；同时，针对电网电压严重跌落时单一VSG电压支撑能力有限的问题，建立了SVG与VSG混合系统模型，提出了相应的无功分配策略。该策略以SVG优先进行无功补偿为前提重新设计了VSG的无功控制环路，同时引入SVG的电流限制环节，设计了混合系统的具体协同控制流程。最后，通过Simulink仿真验证了理论分析的有效性。结果表明，所提限流策略可有效限制输出电流，混合系统控制方法能大大提升电网电压跌落时的恢复程度。

To address the challenges of current over-limitation and limited voltage support capability in grid-forming energy storage converters during low-voltage ride-through (LVRT) under grid fault-induced voltage sags, this study proposes a coordinated reactive power control strategy for a hybrid Virtual Synchronous Generator (VSG) and Static Var Generator (SVG) system incorporating an LVRT current limiting strategy. Firstly, it introduces a typical control methodology of VSG, and conducted an analysis on the transient characteristic power-angle curves under different levels of grid voltage sags. Subsequently, it developed an improved q-axis priority current limiting strategy by modifying the existing approach, where the active power reference value is proportionally reduced according to the diminished d-axis current, resulting in an adaptive active power reference q-axis priority current limiting approach. Furthermore, to overcome the restricted voltage support capacity of standalone VSG during severe grid voltage sags, a collaborative control framework integrating SVG with VSG is established, accompanied by a reactive power allocation strategy. The strategy redesigns the reactive power control loop of VSG with SVG priority for reactive power compensation as a prerequisite, while introducing the current limiting mechanism of SVG and designing the specific cooperative control process for the hybrid system. The effectiveness of the proposed methodology is conclusively validated through Simulink simulation results. The experimental results demonstrate that the proposed current limiting strategy effectively restricts the output current, while the hybrid system control methodology significantly enhances voltage recovery performance during grid voltage sags.