太阳能辅助燃煤发电系统变工况动态特性分析

针对某600 MW亚临界机组太阳能辅助燃煤发电系统，选择夏至日全天100%THA、75%THA、50%THA3个运行工况，使用TRNSYS瞬态模拟软件，在太阳辐射日变化的条件下，对接入太阳能辅助燃煤发电系统后机组运行的动态特性进行了模拟。结果显示，不同工况下太阳能辅助燃煤发电系统的运行受到太阳能辐照波动的影响，变工况下的系统主要参数变化与流量变化密切相关，太阳能系统运行时锅炉主蒸汽温度升高，烟温降低，压力降低，负荷越低光电转化效率越低。在变工况过程中太阳能接入锅炉会造成主汽温度的升高，必须采取动态喷水减温措施控制主蒸汽温度，维持太阳能侧和锅炉侧的换热平衡。

Analysis on Dynamic Characteristics of Solar-aided Coal-Fired Power Generation System under Load Following

Regarding a 600 MW sub-critical solar-aided coal-fired power generation unit, the transient simulation software TRNSYS is used to simulate its operating dynamic characteristics under 100%THA, 75%THA and 50%THA conditions on the summer solstice upon the introduction of the solar energy considering daily solar radiation changes. The results show that the operation of the solar-aided coal-fired power generation system under different operating conditions is affected by solar radiation fluctuations. The change of main parameters is closely related to the flow rate. Specifically, the main steam temperature will go higher with the main steam pressure and flue gas temperature down when the solar-aided system is in operation. The solar-electricity conversion efficiency of the solar-aided system will decrease with the load drop. During the load following process, the introduction of solar energy into boiler will cause main steam temperature to rise such that the dynamic water spray desuperheating measures must be taken to maintain main steam temperature and keep the heat exchange balance between the solar side and the boiler side.