Experimental investigation of the extreme seeking control on a transcritical CO2 heat pump water heater

Cui, Ce; Zong, Shuo; Song, Yulong; Yin, Xiang; Cao, Feng

doi:10.1016/j.ijrefrig.2021.09.027

Cited by 16 publications

(5 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cecchinato et al obtained a system model using an artificial neural network (ANN) and determined the optimal pressure in real time via PSO [80]. Extremum seeking control (ESC) has been utilized for optimal pressure seeking in several applications [81][82][83][84]. The searching process of ESC is shown in Figure 5.…”

Section: Optimal-pressure-seeking Methodsmentioning

confidence: 99%

“…Energies 2023, 16, x FOR PEER REVIEW 9 of 21 been utilized for optimal pressure seeking in several applications [81][82][83][84]. The searching process of ESC is shown in Figure 5.…”

Section: Optimal-pressure-seeking Methodsmentioning

confidence: 99%

“…The variation of optimum-high-pressure-seeking methods is shown in Table 2. been utilized for optimal pressure seeking in several applications [81][82][83][84]. The s process of ESC is shown in Figure 5.…”

Section: Optimal-pressure-seeking Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Review of Recent Advances in Transcritical CO2 Heat Pump and Refrigeration Cycles and Their Development in the Vehicle Field

Pei

Cai

et al. 2023

Energies

View full text Add to dashboard Cite

Refrigerant substitution is an urgent need in the context of reducing carbon emissions and slowing global warming. CO2 is now being proposed as a promising solution based on its excellent properties and system performance, especially in low-temperature environments. This paper presents an overview of recent advances in system configuration and operation characteristics to improve the performance of transcritical CO2 heat pump and refrigeration systems. The paper first introduces the basic research background, system cycle, and thermodynamic characteristics. Secondly, CO2 cycle improvements with single modifications and modification combinations are reviewed. Then, some important operation characteristics and control methods are discussed. Additionally, the paper provides a detailed description of the development of transcritical CO2 heat pump and refrigeration systems in the vehicle field. At the end of this review, conclusions and opportunities for future work in this field are presented.

show abstract

Section: Optimal-pressure-seeking Methodsmentioning

confidence: 99%

“…Energies 2023, 16, x FOR PEER REVIEW 9 of 21 been utilized for optimal pressure seeking in several applications [81][82][83][84]. The searching process of ESC is shown in Figure 5.…”

Section: Optimal-pressure-seeking Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Review of Recent Advances in Transcritical CO2 Heat Pump and Refrigeration Cycles and Their Development in the Vehicle Field

Pei

Cai

et al. 2023

Energies

View full text Add to dashboard Cite

show abstract

“…As a model-free control strategy without complex algorithms, extreme seeking control (ESC) experimental verification has always been a topic of greatest concern to relevant practitioners. Cui et al [34] used multivariable ESC to optimize the exhaust pressure of a transcritical CO2 heat pump water heater. It was found that the ESC controller increased system COP by 7.62% and 8.81% under fixed design conditions and non-design conditions, respectively.…”

Section: Operational Characterization Studiesmentioning

confidence: 99%

Research progress and applications of transcritical carbon dioxide heat pumps: A review

Mei,

Liu,

Liu

2023

Clean Energ. Sci. Tech.

View full text Add to dashboard Cite

Heat pump technology is an energy-saving technology that can efficiently utilize low-grade energy. It has broad application prospects in building heating, industrial waste heat utilization, new energy and other fields. However, the refrigerants used in traditional heat pump systems have serious negative impacts on the environment, and there is an urgent need to find a safe, environmentally friendly, and efficient alternative refrigerant. As a natural refrigerant, CO2 has good physical and chemical properties and is very suitable as a working fluid in transcritical cycles, showing great advantages in the field of heat pump technology. At present, research on CO2 heat pumps has made certain progress, but there are few reviews of the research status and development trends of CO2 heat pumps in different applications. Therefore, this article systematically summarizes the latest research results of transcritical CO2 heat pumps in different application fields, pointing out the difficulties such as high pressure and low operating efficiency in system design and operation. It also summarizes the latest optimization research on system components, cycle structure, mixed refrigerants and control strategies. The results show that each optimization method can significantly improve system performance, among which mixed refrigerant is the simplest optimization method. Finally, the outlook for CO2 heat pump technology is put forward. With policy support and technological advancement, more comprehensive, energy-saving, and intelligent CO2 heat pump technology will continue to develop and innovate.

show abstract

“…Natural refrigerants that are not harmful to nature have become a very promising choice for heat pumps. Carbon dioxide (CO 2 ) is considered an ideal refrigerant for heat pump water heaters because of its superior environmental friendliness; excellent thermodynamic properties; and safety properties, such as nonflammability, nontoxicity, and chemical stability [5][6][7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Exergy Analysis of Transcritical CO2 Air-Source Heat Pump with Honeycomb Gas Cooler

Zhang,

Wang,

Zhang

et al. 2023

Buildings

View full text Add to dashboard Cite

In order to build an efficient and energy-saving CO2 heat pump system and to improve the heat transfer efficiency of the gas cooler, a novel honeycomb gas cooler with a compact structure, high heat transfer efficiency, and high pressure-bearing capacity was proposed in our previous work. To clarify the components in the system that need further optimization and to improve its performance, an exergy analysis of a transcritical CO2 air-source heat pump system with the novel honeycomb gas cooler is studied in this paper. Based on the second law of thermodynamics, the exergy model of each component in the heat pump system is established, and the irreversible loss of each component is analyzed. In addition, the degree of energy loss of the honeycomb gas cooler is clarified, and the possibility and direction of system optimization are pointed out. The results show that the exergy efficiency of the system is 35.33% under nominal operating conditions, and there is a lot of room for improvement in its energy utilization. The three components with the largest exergy destruction percentage are the compressor, throttle valve, and evaporator in the order of 36.13%, 22.90%, and 19.51%, respectively. These components with high exergy destruction percentages are the main reasons for the large irreversible losses of the system.

show abstract

Experimental investigation of the extreme seeking control on a transcritical CO2 heat pump water heater

Cited by 16 publications

References 19 publications

Review of Recent Advances in Transcritical CO2 Heat Pump and Refrigeration Cycles and Their Development in the Vehicle Field

Review of Recent Advances in Transcritical CO2 Heat Pump and Refrigeration Cycles and Their Development in the Vehicle Field

Research progress and applications of transcritical carbon dioxide heat pumps: A review

Exergy Analysis of Transcritical CO2 Air-Source Heat Pump with Honeycomb Gas Cooler

Contact Info

Product

Resources

About