دانلود رایگان مقاله انگلیسی ذخیره انرژی حرارتی در حرارت ترکیب شده و توزیع توان با توجه به محدودیت های انتقال حرارت - نشریه IEEE

Abstract

Heat transfer (HT) is a major constraint in thermal system analysis. However, when discussing utilizing the flexibility provided by the heating sector, for example using thermal energy storage (TES) to increase operational flexibility of combined heat and power (CHP), the HT process is often ignored. This may mean infeasibility of the resulting schedules. In response to this, this paper proposes a general TES model which takes detailed HT analysis into account. By setting the relevant parameters, this model can be used to describe the HT process for both sensible heat (SH) and latent heat (LH) TES devices. An iteration method is proposed to deal with the nonlinearity introduced by the HT constraints, and to solve the joint nonlinear dispatch problem for CHP with TES. The simulation results show that explicitly considering the HT process is essential to realistically assess and therefore make full use of the flexibility provided by TES. Moreover, the comparison between LH and SH TES shows that LH can provide more flexibility for the system, especially when the starting energy level in the TES device is low.

VII. CONCLUSIONS

In this study, we proposed a general model for thermal energy storage (TES) with detailed consideration of the heat transfer (HT) constraints. This general model can be used to model both the sensible heat (SH) TES and latent heat (LH) TES by using different parameters. An iteration method is given to solve the dispatch problem with these complex nonlinear HT constraints, and interpolation is used to deal with the strong nonlinearity. The case studies demonstrate the effectiveness of the proposed model and solving method. It is also illustrated how considering the HT process is essential to realistically quantify and make full use of the flexibility that the TES can provide. The differences between LH and SH TES are also analyzed, and the results show that LH can provide more flexibility than SH, especially when the starting thermal energy level is low.

Flexibility provided by TES devices will be highly influenced by the HT processes, as demonstrated here. Therefore, future studies will aim to include HT constraints into other thermal flexibility enhancement options such as using the TES capacity of the district heating network, electric boilers, flexible heat consumption, etc.