Inventory control assessment for small scale sCO2 heat to power conversion systems
Inventory control assessment for small scale sCO2 heat to power conversion systems
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DOI：
10.1016/j.energy.2022.126537
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发表时间：
2022-12
期刊：
影响因子：
9
通讯作者：
Matteo Marchionni;Muhammad Usman;Lei Chai;S. Tassou
中科院分区：
文献类型：
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作者：
Matteo Marchionni;Muhammad Usman;Lei Chai;S. Tassou
超临界CO2（sCO2）系统在非设计和瞬态运行期间的主要循环参数控制对提高其技术准备水平至关重要。在较小规模的发电机组（< 0.5-5 MW）中，成本和复杂性限制了电源回路中辅助组件的数量，使控制系统的设计更具挑战性。在可能的策略中，通过改变电力回路中的二氧化碳流体质量来实现给定控制目标的系统库存调节是一种很有前途的选择。然而，这种技术提出了一些尚待充分理解的技术挑战。为了填补这一空白，本研究对库存控制系统进行了全面的稳态和瞬态分析，特别参考了布鲁内尔大学委托的50千瓦sco2测试设备。稳定性的影响（如压力梯度在循环）和可变的库存罐尺寸的影响进行了讨论。油箱容积比功率回路（包括接收器）高3倍，可导致更高的可控性范围（涡轮入口温度的±30%）和控制动作的延长可用性（较慢的油箱排放）。还设计了PI控制器来调节涡轮进口温度在465°C左右的目标，以响应余热变化。
The control of the main cycle parameters in supercritical CO2(sCO2) systems during off-design and transient operation is crucial for advancing their technological readiness level. In smaller scale power units (<0.5–5 MW), costs and complexity constraints limit the number of auxiliary components in the power loop, making the design of the control system even more challenging.Among the possible strategies, the regulation of system inventory, which consists in varying the CO2fluid mass in the power loop to achieve a given control target, represents a promising alternative. Such technique however poses several technical challenges that are still to be fully understood. To fill this gap, this work presents a comprehensive steady-state and transient analysis of inventory control systems, referring in particular to a 50 kW sCO2test facility being commissioned at Brunel University.Stability implications (e.g. pressure gradients in the loop) and the effects of variable inventory tank size are discussed. Tank volumes 3 times higher than the one of the power loop (including the receiver) can lead to a higher controllability range (±30% of the nominal turbine inlet temperature) and an extended availability of the control action (slower tank discharge). A PI controller is also designed to regulate the turbine inlet temperature around the target of 465 °C in response to waste heat variations.