S-CO_(2)发电系统负荷跟随控制策略及动态特性研究

Study on Load Following Control Strategy and Dynamic Characteristics of S-CO_(2)Power Generation System

为了解决超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))发电系统负荷跟随控制策略难以兼具变负荷快速和宽负荷高效的问题,该文针对600 MW S-CO_(2)再压缩循环发电系统,将阀门控制与库存控制耦合并对CO_(2)库存罐的布置形式进行改进,提出一种新型负荷跟随控制策略。与变负荷快速的阀门控制相比,该控制策略在75%~100%变负荷过程中使得系统循环效率最高提升13.73%,循环最高压力降低可达28.2%,降负荷速率相等。通过改进CO_(2)储罐位置使得系统升、降负荷速率分别提升2.75和1.96倍,一次调频性能得到明显提升。最后,通过对51%~100%变负荷过程系统关键参数的动态特性进行研究,证明所设计负荷跟随控制策略的合理性和有效性。

The load following control strategy of the supercritical carbon dioxide(S-CO_(2))power generation system is difficult to combine fast variable load and high efficiency with wide load.To solve such problem,this paper proposes a new load following control strategy for 600 MW S-CO_(2)recompression cycle power generation system by coupling valve control with inventory control.Compared with the valve control,this control strategy increases the cycle efficiency by up to 13.73%and reduces the maximum pressure by up to 28.2%during the 75%~100%variable load process,with an equal load reduction rate.By improving the position of CO_(2)inventory tank,the load-up and load-down rates of the system are increased by 2.75 times and 1.96 times,respectively,and the performance of primary frequency modulation is significantly improved.Finally,by studying the dynamic characteristics of the key parameters of the 51%~100%variable load process,the rationality and effectiveness of the load following control strategy designed are proved.