CN-121983616-A - Electrolysis/power generation reversible system with heat smooth switching function and control method thereof

CN121983616ACN 121983616 ACN121983616 ACN 121983616ACN-121983616-A

Abstract

The invention provides an electrolysis/power generation reversible system with a heat smooth switching function and a control method thereof, relating to the technical field of fuel cells, the system comprises a reversible solid oxide electric pile, a hierarchical thermal buffer framework, a three-way proportional control valve and a controller, wherein the reversible solid oxide electric pile comprises a plurality of single cell units stacked along the axial direction; the hierarchical thermal buffering framework comprises an inner ring thermal buffering plate and an outer ring phase change manifold, wherein the inner ring thermal buffering plate is periodically arranged in the reversible solid oxide cell stack, the outer ring phase change manifold is arranged on an air inlet path, the three-way proportional regulating valve is used for regulating the flow proportion of sweep air entering the reversible solid oxide cell stack through the outer ring phase change manifold, and the controller is internally provided with a thermal state sensing module and a cooperative compensation algorithm and is used for regulating and controlling operation electric parameters and a fluid loop of the cell stack in real time. The system of the invention can realize smooth transition of temperature and prolong the service life of the system by inhibiting transient thermal shock of mode switching through hierarchical thermal buffering and cooperative thermal control.

Inventors

FANG MING
HUANG JU
LEI XIANZHANG
LI YIXING
ZHANG QI
MA XIAOYU
ZHANG WENBIAO

Assignees

天府永兴实验室

Dates

Publication Date: 20260505
Application Date: 20260407

Claims (10)

1. An electrolysis/power generation reversible system with a thermally smooth switching function, characterized by comprising: A reversible solid oxide cell stack including a plurality of unit cell units stacked in an axial direction; the hierarchical thermal buffering framework comprises an inner ring thermal buffering plate and an outer ring phase change manifold, wherein the inner ring thermal buffering plate is periodically arranged inside the reversible solid oxide cell stack, and the outer ring phase change manifold is arranged on an air inlet path; the three-way proportional control valve is used for adjusting the flow rate proportion of the sweep gas entering the reversible solid oxide cell stack to flow through the outer ring phase change manifold; and the controller is internally provided with a thermal state sensing module and a collaborative compensation algorithm and is used for regulating and controlling the operation electric parameters of the electric pile and the fluid loop in real time.
2. The reversible electrolysis/power generation system with the heat smooth switching function according to claim 1, wherein the inner ring heat buffer plate is provided with a non-electrochemical active full-sealed flat metal cavity, a first phase change material is packaged in the inner ring heat buffer plate, and supporting reinforcing ribs which are arranged in a matrix form are arranged in the full-sealed flat metal cavity and used for enhancing heat transfer and bearing the assembling pretightening force of the reversible solid oxide electric pile; Wherein the inner ring heat buffer plate adopts non-uniform variable density arrangement in the axial direction of the reversible solid oxide cell stack, and the arrangement ratio of the single cell unit to the inner ring heat buffer plate is as follows in the end heat compensation area close to the end plates at the two axial ends of the reversible solid oxide cell stack In the heat stable region of the center of the reversible solid oxide cell stack, the arrangement ratio of the single cell unit to the inner ring heat buffer plate is as follows Wherein 。
3. The reversible electrolysis/power generation system with smooth thermal switching as claimed in claim 2, wherein the outer ring phase change manifold is internally encapsulated with a second phase change material having a phase change temperature of Lower than the phase transition temperature of the first phase change material 。
4. The reversible electrolysis/power generation system with smooth thermal switching of claim 1, wherein the controller comprises an ASR virtual sensing module for monitoring the operating voltage V and current I of the reversible solid oxide cell stack in real time, calculating an area specific resistance ASR, and based on the ASR, identifying the phase change plateau of the inner loop thermal buffer plate, estimating the cell stack state of charge And the method is used for monitoring inlet and outlet temperature differences and flow of the outer ring phase change manifold in real time and estimating the state of charge of the outer ring ; The controller is also configured to switch transients in response to a mode And (3) with The bias amount of the operation voltage relative to the thermal neutral voltage is dynamically adjusted, and the opening degree of the three-way proportional control valve is adjusted.
5. A control method for the electrolysis/power generation reversible system having a heat smoothing switching function according to any one of claims 1 to 4, characterized by comprising the steps of: Step S1, collecting the operation voltage V, the current I and the inlet and outlet temperatures of the reversible solid oxide electric pile in real time; S2, calculating a dynamic area specific resistance ASR of the reversible solid oxide cell stack; s3, identifying the phase change platform period of the inner ring thermal buffer plate based on the change rate of the ASR; S4, estimating the state of charge of the reversible solid oxide cell stack according to energy integration And estimating the state of charge of the outer ring according to the flow and the temperature difference ; Step S5, when the mode switching instruction is received, according to And (3) with Dynamically adjusting the operating voltage and airflow distribution.
6. The control method according to claim 5, wherein in the step S3, the logic for identifying the phase change plateau is configured to, when the absolute value of the rate of change of ASR over time is monitored to be less than a preset threshold for a continuous preset time When the electric pile enters the phase change platform phase, the corresponding moment is taken as The starting point of the estimation is integrated.
7. The control method according to claim 5, wherein in the step S5, the logic for dynamically adjusting the operation voltage includes: When (when) When the voltage is lower than a preset threshold value, the operating voltage is increased Making it deviate upward from the thermal neutral voltage Voltage offset The deficiency of (2) is positively correlated, and the relation is: In the formula (I), in the formula (II), In order to compensate for the coefficient of the coefficient, In order to achieve the target state of charge, The state of charge of the electric pile at the current moment; and, during a transient state from the power generation mode to the electrolysis mode, a rate of rise of the operating voltage Is that Is a monotonically increasing function of (1).
8. The control method according to claim 5, wherein the logic for dynamically adjusting the airflow distribution in step S5 is: According to The opening degree of the three-way proportional regulating valve is regulated; If it is Is greater than or equal to a first preset threshold, increasing the proportion of the airflow through the outer ring phase change manifold; If it is And if the temperature is smaller than the second preset threshold value, switching to a bypass mode or starting auxiliary preheating.
9. The control method of claim 5, further comprising coordinated control logic of the inner and outer ring states of charge: When (when) And (3) with When the temperature is equal to or higher than the preset threshold value, the system operates in a thermal neutral mode; When only When the voltage is smaller than the corresponding preset threshold value, the internal compensation is preferentially executed by adjusting the operation voltage; When (when) And (3) with When the voltage switching rate is smaller than the preset threshold value corresponding to the voltage switching rate, the system enters a safety protection mode, and the external auxiliary heating is started to maintain heat balance.
10. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, is capable of realizing the control method according to any one of claims 5-9.

Description

Electrolysis/power generation reversible system with heat smooth switching function and control method thereof Technical Field The invention relates to the technical field of fuel cells, in particular to an electrolysis/power generation reversible system with a heat smooth switching function and a control method thereof. Background A reversible solid oxide cell (r-SOC) is an energy conversion device capable of bi-directional operation between a fuel cell mode (SOFC, power generation) and an electrolyser mode (SOEC, hydrogen production). In SOEC mode, an exothermic electrochemical reaction occurs inside the stack, and in SOEC mode, an endothermic electrochemical reaction occurs inside the stack. The prior art generally employs external electrical heating or simple air flow preheating to maintain the stack temperature and monitors temperature changes by a temperature sensor disposed outside the stack for feedback control. However, in the related art, there is a problem in that, firstly, since the reaction heat properties of SOFC and SOEC modes are quite opposite, abrupt change of reaction heat may cause severe temperature gradient inside the stack in the mode switching transient state, which is very liable to cause cracking of the brittle ceramic electrolyte membrane, i.e., thermal shock risk. Meanwhile, the traditional external electric heating compensation mode is low in response speed and high in energy consumption, the temperature inside the electric pile is difficult to directly and accurately monitor, the problem of perception lag exists, and transient temperature fluctuation cannot be effectively restrained. In addition, the waste heat generated by SOFC modes is usually directly discharged, and cannot be effectively reused in mode switching, so that the overall energy utilization rate of the system is low. Disclosure of Invention In order to solve at least part of the technical problems in the related art, the invention provides an electrolysis/power generation reversible system with a heat smooth switching function and a control method thereof. In order to achieve the above purpose, the technical scheme adopted by the invention comprises the following steps: according to a first aspect of the present invention, there is provided an electrolysis/power generation reversible system with a thermally smooth switching function, comprising: A reversible solid oxide cell stack including a plurality of unit cell units stacked in an axial direction; the hierarchical thermal buffering framework comprises an inner ring thermal buffering plate and an outer ring phase change manifold, wherein the inner ring thermal buffering plate is periodically arranged inside the reversible solid oxide cell stack, and the outer ring phase change manifold is arranged on an air inlet path; the three-way proportional control valve is used for adjusting the flow rate proportion of the sweep gas entering the reversible solid oxide cell stack to flow through the outer ring phase change manifold; and the controller is internally provided with a thermal state sensing module and a collaborative compensation algorithm and is used for regulating and controlling the operation electric parameters of the electric pile and the fluid loop in real time. Optionally, the inner ring thermal buffer plate is provided with a non-electrochemical active full-sealed flat metal cavity, a first phase change material is packaged in the inner ring thermal buffer plate, and supporting reinforcing ribs which are arranged in a matrix form are arranged in the full-sealed flat metal cavity and used for enhancing heat transfer and bearing the assembling pretightening force of the reversible solid oxide electric pile; Wherein the inner ring heat buffer plate adopts non-uniform variable density arrangement in the axial direction of the reversible solid oxide cell stack, and the arrangement ratio of the single cell unit to the inner ring heat buffer plate is as follows in the end heat compensation area close to the end plates at the two axial ends of the reversible solid oxide cell stack In the heat stable region of the center of the reversible solid oxide cell stack, the arrangement ratio of the single cell unit to the inner ring heat buffer plate is as followsWherein。 Optionally, the outer ring phase change manifold is internally encapsulated with a second phase change material having a phase change temperature ofLower than the phase transition temperature of the first phase change material。 Optionally, the controller comprises an ASR virtual sensing module for monitoring the operation voltage V and the current I of the reversible solid oxide cell stack in real time, calculating an area specific resistance ASR, and based on the ASR, identifying the phase change plateau of the inner loop thermal buffer plate, estimating the cell stack state of chargeAnd the method is used for monitoring inlet and outlet temperature differences and flow of the outer ring phase change