主动支撑电网的双馈风电场故障功率协调控制方法

风电持续开发建设使同步发电机渗透率降低，电力系统抗扰能力不断下降。双馈风电场(doubly-fed wind farm, DFWF)内部故障后，双馈风电机组(doubly-fed wind turbine, DFWT)的切除导致电力系统出现功率缺额，可能威胁系统安全稳定运行。为此，利用故障期间DFWT机械功率与电磁功率不平衡累积的暂态能量，提出了主动支撑电网的双馈风电场故障功率协调控制方法。分析了DFWF内部故障特征，提出了故障全过程功率协调控制的思想。推导了DFWF内部故障下DFWT的转速解析表达式，分析了DFWT暂态能量的特征并给出了最大暂态能量的计算方法。在此基础上，给出了DFWT功率支撑控制参考值与功率支撑控制时间的计算方法，并提出了DFWT故障功率协调控制策略。算例表明，DFWF故障功率协调控制可利用暂态能量最大限度地提供功率支撑，降低DFWF内部故障对电力系统的影响。

Coordinated fault power control method for doubly-fed wind farms with active grid support

The development of wind power has led to a decrease in the penetration rate of synchronous generators, resulting in a reduction in power system resilience. In the case of an internal fault of a doubly-fed wind farm (DFWF), the removal of a doubly-fed wind turbine (DFWT) may cause a power shortage, posing a threat to its safe operation. In light of this, a fault power coordination control method for doubly-fed wind turbines is proposed to actively support the grid by using the transient energy accumulated by the mechanical and electromagnetic power imbalance of the DFWT during the fault. This paper analyzes the characteristics of the DFWF internal fault, proposes the idea of fault full process power coordination control, derives the analytical expression of DFWT speed under DFWF internal fault, analyzes the characteristics of DFWT transient energy, and provides a calculation method for the maximum transient energy. Subsequently, the calculation methods for control reference values of the DFWT and power support time are given and a DFWT fault power coordination control strategy is proposed. The algorithm demonstrates that DFWF fault power coordination control can use transient energy maximally to supply power support and reduce the impact of DFWF internal faults in the power system.