应用于变电站的D-STATCOM综合控制方法研究

Integrated Control Strategy and Application of D-STATCOM in Substation

针对冲击性负荷工作的时段性特点,配网静止无功发生器D-STATCOM要在电力系统中推广应用必须同时具备冲击性负荷补偿和稳态调压的功能。为实现这一目的,提出一种适合于变电站应用的D-STATCOM综合控制方法。先通过冲击性负荷工作状态判断,确定采用稳态调压还是负荷补偿控制方式。若采用稳态调压方式则通过与变电站投切电容支路形成良好配合,实现限值范围内的电压调整。若采用负荷补偿方式则通过实时的限值判断确定无功与各次谐波电流的补偿重点,以基于瞬时无功功率理论的电流检测方法为基础,结合直流侧电压的直接PI控制算法和补偿电流的增量迭代式广义积分控制算法实现基波与各次谐波的分频控制。控制方法易于工程实现,D-STATCOM可实现多种功能,有利于提高装置的性价比。现场应用证明了装置的有效性。

Integrated control strategy for D-STATCOM in the substation is proposed, aiming at equipped D-STATCOM with functions of impulse load compensation and steady voltage regulation according to characteristic of impulse load. Through checking situation of impulse load, function is decided to apply, steady voltage regulation or impulse load compensation. The compensation priority between harmonic and reactive power is confirmed by limit values judgment and the theory of instantaneous reactive power is used to detect the reference current. The frequency dividing control of harmonic and fundamental wave is realized by the integration of DC voltage PI control algorithm and incremental iteration approach of compensated current based on generalized integrator. The proposed method has strong applicability. It helps to imorove the D-STATCOM oerformance/orice ratio, and thus widen its annlieation.