Small modular reactors(SMRs) are beneficial in providing electricity power safely and viable for specific applications such as seawater desalination and heat production. Due to its inherent safety feature, the modular...Small modular reactors(SMRs) are beneficial in providing electricity power safely and viable for specific applications such as seawater desalination and heat production. Due to its inherent safety feature, the modular high temperature gas-cooled reactor(MHTGR) is considered as one of the best candidates for SMR-based nuclear power plants. Since its dynamics presents high nonlinearity and parameter uncertainty, it is necessary to develop adaptive power-level control, which is beneficial to safe, stable, and efficient operation of MHTGR and is easy to be implemented. In this paper, based on the physically-based control design approach, an adaptive outputfeedback power-level control is proposed for MHTGRs. This control can guarantee globally bounded closedloop stability and has a simple form. Numerical simulation results show the correctness of the theoretical analysis and satisfactory regulation performance of this control.展开更多
正温度系数(Positive temperature coefficient, PTC)材料是一种电阻随温度变化的热控功能材料,然而,传统的PTC材料由于高室温电阻率以及负温度系数效应而限制了其在电子设备热控领域的应用。本文基于石蜡/乙烯–醋酸乙烯酯共聚物混合基...正温度系数(Positive temperature coefficient, PTC)材料是一种电阻随温度变化的热控功能材料,然而,传统的PTC材料由于高室温电阻率以及负温度系数效应而限制了其在电子设备热控领域的应用。本文基于石蜡/乙烯–醋酸乙烯酯共聚物混合基体,利用多壁碳纳米管和炭黑杂化填料的协同效应制备得到具有室温居里点、低室温电阻率和优异电阻正温度效应的新型PTC材料。研究了基体配比、填料含量对室温电阻率和PTC性能的影响,并采用羧甲基纤维素对其负温度系数效应现象进行改善。此外,对新型PTC材料的自适应热控性能进行了研究和分析。研究发现:与普通的电阻加热器相比,PTC加热器具有自适应控温能力,并且在没有任何外部控制系统的条件下可以将被控设备的温度控制在正常工作温度范围内。展开更多
文摘Small modular reactors(SMRs) are beneficial in providing electricity power safely and viable for specific applications such as seawater desalination and heat production. Due to its inherent safety feature, the modular high temperature gas-cooled reactor(MHTGR) is considered as one of the best candidates for SMR-based nuclear power plants. Since its dynamics presents high nonlinearity and parameter uncertainty, it is necessary to develop adaptive power-level control, which is beneficial to safe, stable, and efficient operation of MHTGR and is easy to be implemented. In this paper, based on the physically-based control design approach, an adaptive outputfeedback power-level control is proposed for MHTGRs. This control can guarantee globally bounded closedloop stability and has a simple form. Numerical simulation results show the correctness of the theoretical analysis and satisfactory regulation performance of this control.
文摘正温度系数(Positive temperature coefficient, PTC)材料是一种电阻随温度变化的热控功能材料,然而,传统的PTC材料由于高室温电阻率以及负温度系数效应而限制了其在电子设备热控领域的应用。本文基于石蜡/乙烯–醋酸乙烯酯共聚物混合基体,利用多壁碳纳米管和炭黑杂化填料的协同效应制备得到具有室温居里点、低室温电阻率和优异电阻正温度效应的新型PTC材料。研究了基体配比、填料含量对室温电阻率和PTC性能的影响,并采用羧甲基纤维素对其负温度系数效应现象进行改善。此外,对新型PTC材料的自适应热控性能进行了研究和分析。研究发现:与普通的电阻加热器相比,PTC加热器具有自适应控温能力,并且在没有任何外部控制系统的条件下可以将被控设备的温度控制在正常工作温度范围内。
