功率调节与STATCOM输出电压关系的灵敏度分析

Sensitivity analysis of relation between power control and output voltage of STATCOM

为定量分析静止无功补偿器(STATCOM)传递功率与其交流侧输出电压之间的关系,采用了基于灵敏度的分析方法。以基尔霍夫电压定律为基础,列写了STATCOM系统的电压相量方程,并根据实部与虚部得到两个独立等式。通过计算STATCOM交流侧输出电压有效值与相角对有功功率和无功功率的偏导数,求出了相应的灵敏度。灵敏度计算结果表明,当系统侧电压、线路参数均不变时,STATCOM交流侧输出电压有效值和相角均主要受无功功率的影响,受有功功率影响较小。同时用直接求取法计算STATCOM交流侧输出电压,通过与灵敏度法的计算结果进行数值比较,验证灵敏度分析方法的准确性。

To quantitatively study relationship between the transferred power and the AC output voltage of STATCOM, the method based on the sensitivity analysis is utilized. The voltage phasor equation of STATCOM is established based on the KVL, and two independent equations are acquired according to the real component and the imaginary component, respectively. By calculating partial derivatives of the RMS value and the phase angle of STATCOM AC output voltage to the active power and the reactive power, corresponding sensitivity results are obtained. It shows that the influence of the reactive power on the RMS value and the phase angle of AC output voltage is much greater than that of the active power. Moreover, the AC output voltages of STATCOM calculated by the direct method are compared with those by the sensitivity method, verifying the correctness and accuracy of the presented sensitivity method.