考虑主蒸汽压力的燃煤机组调速模型的分析与改进

为满足电网对火电机组一次调频能力的要求,对燃煤机组调速模型进行了研究。针对现有PSD-BPA模型中因模型不完善导致无法考虑主蒸汽压力影响的问题,通过分析汽轮机在滑压运行工况下主蒸汽压力对于一次调频出力的影响,提出了改进的GK和TB模型,并进行了仿真验证;提出了压力裕度的概念,给出了机组在运行负荷下要保证一次调频出力达到6%额定负荷时的压力应高于阀门全开时压力的12%。

Analysis and Improvement of Speed Governor Model Considering the Main Steam Pressure Influences

In order to meet the requirements for primary frequency regulation capacity of thermal power plants in power grids, the study on speed governor modeling of coal-fired power generation units is conducted. Aiming at the problems existing in the PSD-BPA models with no considerations on the main steam pressure due to the incompleteness of the models, by analyzing the influences of main steam pressure on the primary frequency regulation capacity of steam turbines under the sliding pressure operation condition, the improved GK and TB models are proposed and verified through simulation. In addition, the concept of pressure margin is proposed, which suggests that the operation pressure should be 12% higher than that at full valve opening when the primary frequency regulation capacity reaching as much as 6% of the rated load.