CN-122014370-A - Carnot battery energy storage system

CN122014370ACN 122014370 ACN122014370 ACN 122014370ACN-122014370-A

Abstract

The invention discloses a Carnot battery energy storage system which comprises an electric heater, a heat storage device, a turbine expander and a generator, wherein a heat storage circulating pipeline is further connected between the electric heater and the heat storage device, a heat release circulating pipeline is further connected between the heat storage device and the turbine expander, and a power output end of the turbine expander is connected with an input end of the generator. The Carnot battery energy storage system has the advantages of higher energy utilization rate, better output adjustability, quick heat storage response, high heating efficiency and good stability.

Inventors

Yin Leqing
DU YANG
Hui Jicheng
WU HAIFENG
CHEN HONGBING
MA RUIJIANG
XU RONGJI

Assignees

国网上海市电力公司
北京建筑大学

Dates

Publication Date: 20260512
Application Date: 20260402

Claims (10)

1. The heat storage device comprises a first heat storage module, a second heat storage module and a third heat storage module, wherein a heat storage pipeline channel, a heat release pipeline channel and a heat storage cavity containing solid-liquid phase change materials are respectively arranged in each heat storage module, the solid-liquid phase change materials in the first heat storage module, the second heat storage module and the third heat storage module are sequentially connected in series in the heat storage pipeline and form a series connection with the electric heater, and the heat storage pipeline channels of the first heat storage module, the second heat storage module and the first heat storage module are sequentially connected in series in the heat storage pipeline and form a series connection with the heat release engine.
2. The canola battery energy storage system of claim 1, wherein the thermal storage device is generally rectangular in configuration and the first, second and third thermal storage modules are stacked in sequence from top to bottom.
3. The canola cell energy storage system of claim 1, wherein in each heat storage module, the heat storage pipeline channel is positioned at the lower side of the heat storage chamber, the heat release pipeline channel is positioned at the upper side of the heat storage chamber, and each of the heat storage pipeline channel and the heat release pipeline channel is in a zigzag wave shape at the side adjacent to the heat storage chamber.
4. The canola battery energy storage system of claim 1, wherein the solid-liquid phase change material is an inorganic salt mixture phase change material; the phase transition temperatures of the respective solid-liquid phase change materials in the first, second and third heat storage modules are 700 ℃, 600 ℃ and 500 ℃.
5. The carnot battery energy storage system of claim 1, wherein in each heat storage module, a heat transfer interlayer chamber is further arranged on one side adjacent to the heat storage pipeline channel and the heat storage chamber, a heat transfer fluid medium is arranged in the heat transfer interlayer chamber, one end of the heat transfer interlayer chamber is communicated with a heat transfer pipeline, the heat transfer pipeline is connected into the heat storage chamber to form a heat transfer pipe network and is connected back to the heat transfer interlayer chamber to form a circulation, and a heat transfer circulating pump is arranged on the heat transfer pipeline.
6. The carnot battery energy storage system of claim 5 wherein said heat transfer tube network comprises trunk heat transfer tubes horizontally disposed on a side of said heat storage tube channel away from said heat storage tube channel, said trunk heat transfer tubes having a plurality of vertically connected branch heat transfer tubes uniformly distributed thereon, said branch heat transfer tubes being arranged in a serpentine back and forth configuration and connected back to said heat transfer interlayer chamber.
7. The canola cell energy storage system of claim 5, wherein the heat transfer conduit and heat transfer circulation pump thereon are located outside the heat storage chamber; a layer of porous heat conducting material is further arranged on the inner wall of the heat transfer interlayer cavity and the adjacent side of the heat storage pipeline channel; the heat transfer fluid medium is a liquid-gas phase change material, and the phase change temperature of the liquid-gas phase change material is greater than the phase change temperature of the solid-liquid phase change material in the heat storage module.
8. The carnot battery energy storage system of claim 1 wherein the turbo expander has an output port and three return ports, a heat release circulation pump is installed on a heat release circulation pipe connected to the output port of the turbo expander and connected to a third heat storage module, a heat release circulation pipe connected to the third heat storage module is connected to the second heat storage module and further connected to a third heat release return branch, a third heat release return branch switching valve is installed on the third heat release return branch and connected to a return port of the turbo expander, a second heat release switching valve is also installed on the heat release circulation pipe between the third heat release return branch and the second heat storage module, a second heat release return branch is also connected to the heat release circulation pipe connected to the second heat storage module, a second heat release return branch switching valve is installed on the second heat release return branch and connected to another return port of the turbo expander, a first switch valve is also installed on the heat release path between the second heat release return branch and the first heat storage module, and a third return port of the heat release circulation pipe connected to the heat storage module.
9. The Kano battery energy storage system of claim 8, wherein the electric heater has an output port and three return ports, a heat storage circulating pump is installed on a heat storage circulating pipe connected to the output port of the electric heater and connected to the first heat storage module, a heat storage switch valve at the input end of the first heat storage module is installed on the heat storage circulating pipe near the input end of the first heat storage module, a first heat storage bypass branch and a second heat storage bypass branch are also connected to the heat storage circulating pipe between the heat storage circulating pump and the heat storage switch valve at the input end of the first heat storage module, the first heat storage bypass branch is installed with the first heat storage bypass heat storage switch valve and connected to the heat storage circulating pipe between the first heat storage module and the second heat storage module, the second heat storage bypass branch is installed with the second heat storage bypass heat storage switch valve and connected to the heat storage circulating pipe between the second heat storage module and the third heat storage module, a return port for returning the electric heater is also connected to the circulating pipe between the first heat storage module and the second heat storage module, the first heat storage reflux branch is also provided with a first heat storage reflux branch heat storage switch valve, a heat storage circulating pipeline between the first heat storage reflux branch and the first heat storage bypass branch is also provided with a second heat storage module input heat storage switch valve, the heat storage circulating pipelines between the second heat storage module and the third heat storage module are respectively provided with a second heat storage module output end heat storage switch valve and a third heat storage module input end heat storage switch valve at two sides of the second heat storage bypass branch, the heat storage circulating pipeline between the second heat storage module output end heat storage switch valve and the third heat storage module input end heat storage switch valve is also provided with a second heat storage reflux branch and connected with the other reflux mouth of the reflux electric heater, the second heat storage reflux branch heat storage switch valve is arranged on the heat storage circulating pipeline between the second heat storage module output end and the third heat storage module, and the heat storage circulating pipeline of the third heat storage module output end is connected with the third reflux mouth of the reflux electric heater.
10. The carnot battery energy storage system of claim 9 wherein the respective heat storage chambers of the first, second and third heat storage modules are each provided with a thermometer and are connected to a control center, the control center being connected to each heat storage switch valve and each heat release switch valve; a thermometer is arranged in each pipeline positioned in front of and behind each heat storage module in the heat storage circulation pipeline and the heat release circulation pipeline and is connected with a control center; The first heat storage module input end heat storage switch valve, the first heat storage bypass branch heat storage switch valve, the second heat storage bypass branch heat storage switch valve, the first heat storage reflux branch heat storage switch valve, the second heat storage module input end heat storage switch valve, the second heat storage module output end heat storage switch valve, the third heat storage module input end heat storage switch valve and the second heat storage reflux branch heat storage switch valve are all flow regulation switch valves capable of realizing flow regulation, and each flow regulation switch valve is respectively connected with a control center.

Description

Carnot battery energy storage system Technical Field The invention relates to the technical field of large-scale energy storage, in particular to a Carnot battery energy storage system. Background Carnot battery refers to a large-scale electric energy storage system based on heat storage. The carnot cell converts electrical energy to thermal energy (THERMAL ENERGY), stores the thermal energy in a thermal storage medium, such as a molten salt phase change material, and when electrical energy is required, the thermal energy is converted to electrical energy by a specific device for reuse. Along with the continuous improvement of the permeability of renewable energy sources, a large-scale and long-term energy storage technology becomes a key for the stable operation of a power grid. Carnot batteries are widely focused as a large-scale physical energy storage technology based on thermodynamic cycle due to large energy storage capacity, long service life and excellent cost potential. The existing Carnot battery system generally adopts a single-tank or double-tank molten salt sensible heat storage technology, but the defects that the heat storage response of the device is slower, the energy utilization rate is lower, the waste is larger, the output adjustability is poorer, the heating efficiency and the stability are difficult to consider and the like exist. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a Carnot battery energy storage system which has the advantages of higher energy utilization rate, better output adjustability, quick heat storage response, high heating efficiency and good stability. In order to solve the technical problems, the invention adopts the following technical scheme: The heat storage device comprises a first heat storage module, a second heat storage module and a third heat storage module, wherein a heat storage pipeline channel, a heat release pipeline channel and a heat storage cavity containing solid-liquid phase change materials are respectively arranged in each heat storage module, the solid-liquid phase change materials in the first heat storage module, the second heat storage module and the third heat storage module are sequentially connected in series in the heat storage pipeline and form a series connection with the electric heater, and the heat storage pipeline channels of the first heat storage module, the second heat storage module and the first heat storage module are sequentially connected in series in the heat storage pipeline and form a series connection with the heat release engine. In this way, when the electric heater generates heat during charging and energy storage, heat is sequentially conveyed through the first heat storage module, the second heat storage module and the third heat storage module by means of a heat storage fluid medium in the heat storage circulating pipeline, and solid-liquid phase-change materials in the heat storage circulating pipeline are sequentially heated. The heat storage fluid medium with the temperature reduced after heat exchange of the first heat storage module is heated by the second heat storage module with the phase change temperature reduced, and is heated by the third heat storage module with the phase change temperature reduced after the temperature reduced again. Therefore, the waste of heat is well avoided in the heat storage process. When the heat is released to generate electricity, the temperature is gradually preheated from low temperature, medium temperature to high temperature by means of the heat release fluid medium in the heat release circulation pipeline through the third heat storage module, the second heat storage module and the first heat storage module, and finally, the higher temperature is obtained to heat and apply work for the turbine expander, and the final heating effect is improved by means of gradual heating of the temperature. Therefore, the multistage heat storage module is utilized in the heat storage and release power generation process to realize the gradient heating utilization of the temperature, so that the waste is better avoided, and the energy utilization efficiency is improved. Further, the whole heat accumulation device is of a rectangular structure, and the first heat accumulation module, the second heat accumulation module and the third heat accumulation module are sequentially overlapped from top to bottom. The structure is simple and compact, the implementation is easy, and the heat loss of the heat storage module can be better avoided. Further, in each heat storage module, the heat storage pipeline channel is positioned at the lower side of the heat storage cavity, the heat release pipeline channel is positioned at the upper side of the heat storage cavity, and one side of each of the heat storage pipeline channel and the heat release pipeline channel adjacent to the heat storage cavity is in a zigzag wave shape. Therefore, heat storage and