槽塔结合的太阳能辅助燃煤发电系统时空协同集成机理与调控机制研究

Coal-fired power generation system is of stable power output, but it is facing the stress of energy saving and pollutant mitigation. The solar power system is environment friendly but it is of unstable output and high cost. With the integration of solar field and coal-fired power plant, they can share turbines and other key equipment. Because of the reasonable combinations between the time delay of thermal and heat storage system, the solar aided coal-fired power generation has typical characteristics: stable and regulated output power, power grid dispatching ability. This project takes heat as energy transfer medium to combine solar thermal power generation system, which has power transient feature, with coal-fired power generation with steady power output. In order to eliminating the defects of the fluctuation of and high cost of the solar thermal power system, collaborative temporal integration mechanism and regulatory mechanism of hybrid system of coal-fired power generation and solar thermal power generation will be explored. The collaborative time-space integration new idea and evaluation criteria of hybrid system of coal-fired power generation and solar thermal power generation will be put forward by studying the thermal-to-power conversion mechanism of core unit components in solar thermal power generation system and the characteristics of power output with variable conditions. In order to address the impact of fluctuations in solar energy on the hybrid system, and achieve stability operations and high thermal-to-power conversion rate of hybrid system and promote large-scale use of solar energy, the optimal allocation principle of the capacity of study thermal storage system and, on basis of the weather and load conditions, the operational status response mechanism of the hybrid system will also be explored at the same time.

燃煤机组具有大延时性和稳定性特点但面临节能减排压力，而太阳能集热环境友好但输出功率受气象条件波动制约，通过将太阳能集热场与燃煤机组合理匹配，并共享汽轮机等关键设备，由于热的延时性加之蓄热系统的优化，使得太阳能辅助燃煤发电系统具有输出功率稳定 且可调控、电网可调度的典型特征。本项目以热为能量传输纽带，将具有功率瞬变特性的塔式和槽式镜场与输出功率平稳的燃煤机组依据“温度对口，梯级利用”的原则有机集成，开展太阳能辅助燃煤发电系统时空协同集成机理与调控机制的基础研究，解决光热发电负荷波动与成本较高和燃煤机组环保性差的弊端。通过研究光热发电系统核心单元部件的热功转化机理和变工况下功率输出特性规律，提出槽塔结合的太阳能辅助燃煤发电系统时空协同集成新思路与评价准则。研究系统蓄热容量优化配置原则，探索基于气象与负荷条件的太阳能辅助燃煤发电系统运行状态响应机制。切实解决太阳能波动对系统运行的影响。

本项目针对槽塔结合辅助燃煤发电系统时空协同集成机理与调控机制不明确等物理问题，开展系统集成机理、关键部件和调控机制的研究。基于太阳能、燃料化学能和热能的综合高效梯级利用，建立槽式、塔式以及槽塔结合辅助燃煤发电系统模型。通过对定日镜场布局的优化，揭示集热场、蓄热单元的对太阳能辅助燃煤机组的影响规律。通过构建不同的槽塔结合辅助燃煤发电系统方案，实现不同温度品位的能量梯级利用，提高能量利用效率，揭示不同耦合方法的槽塔结合太阳能辅助燃煤发电系统的热力学性能变化规律。通过研究槽塔结合太阳能辅助燃煤发电系统中两种太阳能扰动对耦合系统热力过程的双重影响机理，揭示不同负荷条件下槽塔结合太阳能辅助燃煤发电系统对两种太阳能集热方式的最大耦合量变化规律及不同耦合量下系统热力性能。基于热力学第二定律和热经济学原理研究塔式太阳能辅助燃煤发电系统中太阳能的贡献度，揭示太阳能热在系统中的分布关系。通过对整体复杂能量系统的运行参数和能量调度优化方法进行研究，结合控制输入参数的安全约束条件，发展模型预测控制方法，利用预测天气负荷及电站负荷需求信息优化耦合系统在持续时间内的运行控制参数，为太阳能辅助燃煤发电系统及其他综合能源系统的全局运行优化提供参考。