Multi-objective coordinated control of high inertia energy storage synchronous condenser during entire LVRT process

The high inertia energy storage synchronous condenser (HIESSC) can provide both grid voltage and frequency support, which is a promising new type of grid-supporting equipment. However, HIESSC needs to achieve multiple objectives including rotor current limitation, reactive power support, torque ripple limitation, and fast demagnetization under grid fault conditions, and the compatibility among these objectives remains unclear. To address this issue, this paper proposes a multi-objective coordinated control strategy for HIESSC during the low voltage ride-through (LVRT) process from the perspective of the rotor-port impedance characteristics. First, the transient inductance values required to meet different LVRT objectives are analyzed, and the compatibility between different objectives is clarified. Then, the LVRT process of HIESSC is divided into three stages, and the control objectives that need to be optimized in different stages are clarified. Subsequently, through the stage-by-stage design of current control commands, coordinated multi-objective satisfaction throughout the entire LVRT process is achieved. Finally, the proposed method is verified through experiments.