直流功率调制抑制交流联络线随机功率波动的研究

Suppressing AC Tie-line Stochastic Power Fluctuation by HVDC Power Modulation Control

正常运行时华北、华中两大区互联系统交流联络线上存在随机功率随机波动的现象,限制了联络线的输电能力,并直接威胁着设备的安全运行。减小和抑制大区交流联络线上的随机功率波动是当前调度运行亟待解决的重要问题。提出直流功率调制抑制交流联络线随机功率波动的方法,通过直流功率调制快速吸收或补偿其所连交流系统的过剩或缺额功率,可减小或抑制交流联络线上的随机功率波动。提出基于功率调节比的直流调制控制器性能指标,并采用改进的粒子群算法求取控制器最优增益,可使直流线路按预先给定的调节比部分或完全承担交流联络线上的随机功率波动。对华北—华中互联系统的仿真研究表明,直流功率调制为减小或抑制特高压交流联络线上的随机功率波动提供了一种有效手段。

The stochastic power fluctuation on an AC tie-lie of two-area interconnected power systems under normal operating conditions reduces the fie-lie＇s transmission capacity and threatens the secure operation of equipment. Reducing and suppressing the AC tie-line power fluctuation becomes one of the most important issues to be solved in operations. Suppressing AC tie-line stochastic power fluctuation by high voltage direct current （HVDC） power modulation control was proposed. A surplus or shortage of power in an AC area could be absorbed or compensated rapidly by its connected HVDC power modulation, so the power fluctuation on the AC tie-lie could be reduced or suppressed. The HVDC modulation performance index considering power regulation ratio was presented, and the optimal gain of the HVDC modulation controller was solved by an improved particle swarm optimization （PSO） algorithm. Thus, the HVDC transmission line could share the stochastic power fluctuation partially or totally with the AC tie-line. Cases studies on the North China and Central China interconnected power system show that HVDC power modulation provides an effective way to reduce or suppress the stochastic power fluctuation on the ultra-high voltage tie-line.