Dynamic Modeling and Flexibility Analysis of an Integrated Electrical and Thermal Energy System With the Heat Pump–Thermal Storage

Abstract

The integration of high-efficiency heat pump and thermal storage devices is of great significance to realize the synergy between efficient and flexible operation of the integrated electric and thermal energy systems. This article proposed an integrated electric–thermal energy system with heat pump and thermal storage devices and introduced the heat current method for constructing its overall dynamic power flow model by considering energy transfer, conversion, and storage processes. On this basis, we derived the overall system constraint and component constraint equations. Under the objective of wind power curtailment minimization, the comprehensive effects of the dynamic characteristics of the heat pump, thermal storage capacity, new wind power installation, and new heat load on the electric and thermal output are analyzed. The results show that the dispatching accuracy of wind power output can be improved by up to 8% by taking into account the dynamic characteristics of the heat pump. The combination of heat pump and thermal storage device results in a leverage factor of 3.06 and 0.17 for the storage and release processes, respectively, effectively increasing the flexibility of system scheduling. The coordination between the newly added wind power installation and the added new heat load, with the higher operating temperature of the heat pump, is more conducive to promote wind power accommodation and improve the system’s overall flexibility. These results provide the necessary basis for the development of an integrated dispatch plan for the integrated electric and thermal energy systems containing the heat pump–thermal storage.

A review on configuration optimization of hybrid energy system based on renewable energy

“…Cui et al (2022) cited the flexibility index of air source heat pump with waste heat recovery considering dynamic characteristics in integrated energy system. Hao et al (2022) further studies the impact of energy storage devices on the flexibility of the hybrid energy system. In addition to the influence of equipment characteristics in the hybrid energy system on the flexibility index, the variability of the load side also has an impact on the flexibility index of the hybrid energy system.…”

Matrixed modeling method and entropy generation minimization analysis of heat supply system based on standard thermal resistance

“…Meanwhile, Chen et al 37 proposed the heat current method based on the thermoelectric analogy to model thermal systems. The heat current method has provided an alternative and feasible solution for the modeling and optimization of various energy systems from the energy transfer perspective, such as integrated ground source heat pump‐photovoltaic‐thermal system, 38 sCO 2 recompression system, 39 refrigeration system, 40 heat transfer system, 41,42 thermoelectric cooling system, 43 and integrated energy system 44–48 . The system linear constraint equations can be directly used for thermal system optimization by reducing the unnecessary intermediate parameters.…”

“…The heat current method has provided an alternative and feasible solution for the modeling and optimization of various energy systems from the energy transfer perspective, such as integrated ground source heat pumpphotovoltaic-thermal system, 38 sCO 2 recompression system, 39 refrigeration system, 40 heat transfer system, 41,42 thermoelectric cooling system, 43 and integrated energy system. [44][45][46][47][48] The system linear constraint equations can be directly used for thermal system optimization by reducing the unnecessary intermediate parameters. Therefore, this inlet temperature difference-based STR and heat current method will also provide an alternative solution for the entropy generation analysis optimization of thermal and energy systems.…”