水力耦合机组的负荷调节及优化研究

Research on Load Regulation and Optimization of Hydraulic Coupling Units in Hydropower Plant

针对具有水力耦合的发电机组在大波动过程中存在较大水力波动和频率调节缓慢的问题,建立了水力、机械和电气的耦合精细模型,当电力系统负荷变化时,根据削峰填谷的原则,计算出机组之间最优的间隔调节时间。结果表明,通过错峰调节,可减小调压室水位波动和频率振荡的幅值,但由于两者的波动周期不一致,不能同时满足两者最优的优化效果。通过将一段式开机规律优化为"先快后慢"的两段式开机规律,能够抑制水力干扰引起的水力波动,并使机组在过渡过程中具有良好的动态特性,提高了机组应对电力系统负荷波动时的调节能力和稳定性。

Aiming at large hydraulic fluctuation and slow frequency regulation in the transient process of hydraulic coupling units, a hydro-mechanical-electric model was developed to study the load regulation characteristics of the units. When the load in the power system changed, the optimal interval time between units was calculated according to the principle of ‘peak shifting’. Although the amplitude of surge tank water level fluctuation and frequency oscillation is reduced by peak staggering regulation, the optimal effect of both cannot be satisfied at the same time because of the inconsistent fluctuation period. By optimizing the one-stage start-up law to the two-stage start-up law, the hydraulic fluctuation caused by hydraulic interference is effectively suppressed, and the unit has good dynamic characteristics in the transition process, which improves the adjustment ability and stability of the unit in response to power system load fluctuation.