基于轨迹灵敏度的交直流受端系统暂态电压两阶段控制

针对交直流受端系统暂态电压调控能力不足的现状，提出一种基于轨迹灵敏度的交直流受端系统暂态电压两阶段控制方法。构建以最优无功补偿容量和紧急控制成本最小为目标函数的两阶段暂态电压控制模型。借助摄动法求取暂态电压稳定裕度对控制量的轨迹灵敏度，将非线性暂态电压控制模型转化为二次规划模型来提高暂态电压控制效率。为避免故障期间交直流受端系统暂态电压的大幅跌落，实施静止同步补偿器和新一代调相机协同的预防控制，充分发挥无功补偿装置在暂态电压不同跌落程度下的动态无功支撑优势。针对实施暂态电压预防控制后恢复阶段的低电压延时恢复问题，实施包含基于电压源换流器的高压直流和传统调压措施的紧急控制来加快暂态电压恢复速度。修改后的IEEE 39节点系统和实际系统算例结果验证了所提暂态电压控制方法的准确性和有效性。

Trajectory sensitivity based transient voltage two-stage control in AC/DC receiving end system

Aiming at the situation of insufficient transient voltage regulation ability in AC/DC receiving end system, a transient voltage two-stage control method based on trajectory sensitivity is proposed for AC/DC receiving end system. A two-stage transient voltage control model is constructed with the optimal reactive power compensation capacity and minimum emergency control cost as the objective functions. The perturbation method is used to obtain the trajectory sensitivity of transient voltage stability margin to control quantity, and the nonlinear transient voltage control model is transformed into a quadratic programming model, which improves the efficiency of transient voltage control. In order to avoid serious transient voltage sag of AC/DC receiving end system during the fault period, the prevention control coordinating with static synchronous compensator and new generation synchronous condenser is implemented, which fully exploits the dynamic reactive power supporting advantage of the reactive power compensation devices under different transient voltage sag degrees. Aiming at the low voltage delay recovery problem in the recovery stage after implementing the transient voltage preventive control, the emergency control containing voltage source converter based high voltage direct current(VSC-HVDC) and the traditional voltage regulation measures is implemented to accelerate the transient voltage recovery speed. The accuracy and effectiveness of the proposed transient voltage control method are verified by the simulative results of the modified IEEE 39-bus system and an actual system.