Development of a variable water temperature control method for air source heat pump based on the supply–demand balance. (August 2022)

• Record Type: Journal Article
• Authors: Sun, Yuying; Li, Xintian; Wei, Wenzhe; Xue, Huiyu; Wang, Wei; Deng, Shiming
• Is Part Of: Sustainable energy technologies and assessments. Volume 52:Part D(2022)
• Publication Date: 2022-08
• Subjects: Air source heat pump system -- Variable water temperature control method -- Supply and demand balance -- Energy efficient -- Building clean heating; Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2022.102366
• Languages: English
• ISSNs: 2213-1388

Abstract

Highlights: A control method for supply water temperature of air source heat pump is proposed. This control method makes supply water temperature decrease by 3.7 °C. Coefficient of performance of experimental unit increases by 22.88%. A decrease of 26.16% in building heating energy consumption is achieved. The percentage of PMV between − 0.5 and + 0.5 increases from 48.61% to 87.86%. Abstract: Air source heat pump (ASHP) is one of renewable energy technologies, and has been widely used for space heating. In practice applications, the setting value of its supply water temperature is long-term fixed, resulting in the poor coefficient of performance (COP) under partial load conditions. To improve the COP of ASHP, a real-time variable water temperature (VWT) control method for its supply water temperature was proposed in this work. In this control method, the optimal supply water temperature was calculated based on the supply and demand balance, and used as the setting value of supply water temperature. Then using an ASHP-radiant floor heating system, the feasibility and energy-saving performance of the proposed control method were investigated through experiment and simulation. Results indicate that the ASHP heating system can run smoothly when adopting the proposed VWT control method. Compared with the results in constant water temperature (CWT) control method, in the whole heating season, the COP of ASHP unit in VWT control method is 22.88% higher, while the building heating energy consumption is 26.16% lower. Besides, the percentage of predicted mean vote (PMV) between − 0.5 and + 0.5 increases from 48.61% in CWT control method to 87.86% in VWT control method.