CN-122013256-A - Cross-time-scale multi-electrolytic-tank cooperative scheduling method

CN122013256ACN 122013256 ACN122013256 ACN 122013256ACN-122013256-A

Abstract

The invention discloses a cross-time-scale multi-electrolytic-cell cooperative scheduling method which is applied to an alternating-current coupling photovoltaic hydrogen production system. The method comprises the steps of obtaining solar photovoltaic predicted power data and real-time photovoltaic output power data of an alternating-current coupling photovoltaic hydrogen production system, calculating the upper limit of the number of planned operation electrolytic cells based on the solar photovoltaic predicted power data and the preset rated power of a single electrolytic cell, determining the operation number of target electrolytic cells based on the real-time photovoltaic output power data, the upper limit of the number of planned operation electrolytic cells and the preset power distribution rule, calculating hydrogen production distribution power based on the operation number of target electrolytic cells and the real-time photovoltaic output power data, and generating a converter control instruction based on the operation number of target electrolytic cells, the hydrogen production distribution power and the preset equipment balance rotation mechanism. The invention eliminates frequent start-stop oscillation at the operation boundary and can realize multidimensional space-time balance between the bottom voltage stabilizing control role and the physical equipment.

Inventors

JI ZHENDONG
LIU JUNBIAO
Zhu Zhenman

Assignees

南京理工大学

Dates

Publication Date: 20260512
Application Date: 20260409

Claims (10)

1. The cross-time-scale multi-electrolytic-cell cooperative scheduling method is applied to an alternating-current coupling photovoltaic hydrogen production system, and the system is configured into a source load direct-connection architecture for directly supplying power to a hydrogen production station by a photovoltaic station through an alternating-current transmission line, and is characterized by comprising the following steps: Acquiring solar photovoltaic predicted power data and real-time photovoltaic output power data of a system; calculating the upper limit of the number of the planned operating electrolytic cells based on solar photovoltaic predicted power data and rated power of a single electrolytic cell; determining the running number of the target electrolytic cells based on real-time photovoltaic output power data, the upper limit of the number of the planned running electrolytic cells and a preset power distribution rule; calculating hydrogen production distribution power based on the target running number of the electrolytic cells and real-time photovoltaic output power data; based on the target number of electrolyzer operations, the hydrogen production split power, and the equipment equalization rotation mechanism, a converter control command is generated.
2. The method according to claim 1, characterized in that determining the target number of electrolyzer operations, in particular comprises: Dividing the real-time photovoltaic output power data by the minimum operation power of a single electrolytic cell, and rounding downwards to obtain the initial operation quantity; taking the smaller value of two groups of numerical values of the initial operation quantity and the upper limit of the planned operation electrolytic tank quantity as the basic operation quantity; when the basic operation number is equal to the upper limit of the number of the planned operation electrolytic cells, if the real-time photovoltaic output power data is larger than the product of the basic operation number and the rated power of the single electrolytic cell, judging that photovoltaic output power prediction errors occur; based on the prediction errors, the basic operation quantity is sequentially increased one by one until the real-time photovoltaic output power data is fully consumed or the total quantity limit of the electrolytic cells is reached, and the corrected operation quantity is obtained and is used as the target operation quantity of the electrolytic cells.
3. The method according to claim 1, wherein generating converter control instructions comprises generating photovoltaic end control instructions for controlling a photovoltaic side converter in a system, comprising: Generating a shutdown disconnection instruction; calculating the power voltage change rate according to the power acquired in real time, calculating a dynamic adjustment step length by using the product of the first step length coefficient and the power voltage change rate, and generating a rated power point tracking control instruction according to the dynamic adjustment step length; when the real-time photovoltaic output power data cannot be consumed, calculating a constant direction adjustment step length by using a second step length coefficient, and generating a power limit control instruction according to the constant direction adjustment step length; And comparing the real-time photovoltaic output power data with a hysteresis control threshold value, and judging whether to execute the switching of the rated power point tracking control instruction and the power limiting control instruction or not based on a comparison result.
4. The method of claim 1, wherein generating the converter control command comprises generating a hydrogen-producing end control command for controlling a hydrogen-producing side converter in an ac-coupled photovoltaic hydrogen production system, comprising: the hydrogen production side converter is divided into a first type converter and a second type converter, and the number of the first type converters is set as one; Generating an input voltage stabilization control instruction for a first type of converter; performing data mapping based on hydrogen production distribution power and an electrolytic cell power-voltage characteristic curve to obtain a corresponding electrolytic cell voltage reference value; based on the cell voltage reference, a voltage tracking control command including interleaved parallel modulation and average current sharing control logic is generated for the second type of converter.
5. The method according to claim 1, wherein determining the target number of cells to operate is performed using an adaptive hysteresis loop switching strategy based on real-time photovoltaic output power data, an upper limit on the number of cells to be operated, and a preset power distribution rule, and specifically comprises: Acquiring a current running state variable of the electrolytic tank at the current moment; Based on the current running state variable of the electrolytic tank and the switching judgment parameter, respectively obtaining a corresponding dynamic power increasing threshold value and a corresponding dynamic power decreasing threshold value, wherein the dynamic power increasing threshold value is larger than the dynamic power decreasing threshold value, so as to form an asymmetric hysteresis loop; when the real-time photovoltaic output power data is larger than the dynamic power increasing threshold value and the current operation state variable of the electrolytic tank is smaller than the upper limit of the number of the electrolytic tanks scheduled to be operated, the current operation state variable of the electrolytic tank is increased; when the real-time photovoltaic output power data is smaller than the dynamic power threshold value and the current running state variable of the electrolytic tank is larger than zero, the running state variable of the current electrolytic tank is reduced; And updating the current running state variable of the electrolytic tank as the running quantity of the target electrolytic tank.
6. The method of claim 5, further comprising model construction for quantifying net hydrogen production yield and physical start-stop costs before respectively obtaining the corresponding dynamic power-up threshold and dynamic power-down threshold, specifically comprising: Calculating the difference value of the hydrogen production rate of the total input power of the system represented by the real-time photovoltaic output power data before and after the single operation of the electrolytic cell is increased through the power-efficiency characteristic curve of the electrolytic cell, and constructing a marginal hydrogen production gain model; Acquiring warming-up cost hydrogen equivalent and equipment loss cost hydrogen equivalent; And summing the warming cost hydrogen equivalent and the equipment loss cost hydrogen equivalent to construct an equivalent hydrogen loss model.
7. The method according to claim 6, wherein the corresponding dynamic power-up threshold and dynamic power-down threshold are obtained based on the current operating state variable of the electrolytic cell, respectively, specifically comprising: Obtaining the shortest recovery time of the income; the product of the marginal hydrogen production gain model and the shortest recovery time is equal to the equivalent hydrogen loss model, a hydrogen production net gain balance equation is constructed, and the balance equation is solved to obtain a dynamic power threshold; obtaining the minimum running power and the safety margin power of a single electrolytic cell; Multiplying the current running state variable of the electrolytic cell with the minimum running power of a single electrolytic cell, and superposing safety margin power to obtain a dynamic power threshold value of reducing the machine; The dynamic power threshold value of the machine is larger than the dynamic power threshold value of the machine, corresponding to the running number after the target is increased, and the difference value of the dynamic power threshold value of the machine forms the switching hysteresis bandwidth.
8. The method of claim 1, wherein generating the converter control command includes executing intra-day start-stop logic based on a preset device balance rotation mechanism, and specifically includes: acquiring a priority sequence started on the same day; when the running number of the target electrolytic cells is larger than the current running number of the system, sequentially selecting the stopped electrolytic cells to generate a starting control instruction according to the positive sequence direction of the current day starting priority sequence; And when the running number of the target electrolytic cells is smaller than the current running number, selecting the last started electrolytic cell to generate a stop control instruction based on a first-in last-out principle.
9. The method according to claim 1, characterized in that calculating the upper limit of the number of planned operating cells based on solar photovoltaic predicted power data and a preconfigured rated power of a single cell, in particular comprises: extracting the daily maximum predicted power in the daily photovoltaic predicted power data; Dividing the daily maximum predicted power by the rated power of the single electrolytic cell, and performing upward rounding on the division result to obtain the upper limit of the number of the electrolytic cells scheduled to operate.
10. The method of claim 1, wherein calculating hydrogen production split power based on the target cell operating number and real-time photovoltaic output power data, specifically comprises: When the running number of the target electrolytic cells is greater than zero, the real-time photovoltaic output power data is evenly distributed to the corresponding number of the running electrolytic cells, and single target hydrogen production distributed power is obtained and used as the hydrogen production distributed power.

Description

Cross-time-scale multi-electrolytic-tank cooperative scheduling method Technical Field The invention relates to the technical field of photovoltaic off-grid hydrogen production scheduling and control, in particular to a cross-time-scale multi-electrolytic-tank cooperative scheduling method. Background The photovoltaic off-grid hydrogen production system directly supplies fluctuating photovoltaic electric energy to the alkaline water electrolysis cell cluster through a multi-stage power electronic converter. At present, real-time power distribution of a multi-electrolytic cell cluster generally adopts a stateless algebraic mapping strategy or a segmented starting strategy based on a real-time power interval. The controller directly divides the total power of the currently collected photovoltaic by the minimum operating power or rated power of the single device, and the number of the devices which are required to be operated at present is determined through a preset fixed power threshold value or a simple fixed proportion bandwidth. On the bottom layer control topology configuration, the system architecture is generally configured with a plurality of groups of parallel buck converters at the hydrogen station side, one of the converters with specific numbers is fixedly selected, an input voltage stabilization control mode is executed for maintaining the voltage of the micro-grid alternating current bus, and the other parallel converters are uniformly configured into a constant power tracking mode for passively absorbing the distributed electric energy. However, the prior art is unaddressed by the high frequency physical oscillations of the device at the operational boundaries, as well as the localized device thermal stress concentrations and accelerated aging imposed by the fixed control topology. Disclosure of Invention In view of the above problems in the prior art, the application provides a cross-time-scale multi-electrolytic-cell cooperative scheduling method for solving the technical problems. The technical scheme is that the cross-time-scale multi-electrolytic-cell cooperative scheduling method is applied to an alternating-current coupling photovoltaic hydrogen production system, and the system is configured into a source load direct-connection architecture for directly supplying power to a hydrogen production station by a photovoltaic station through an alternating-current transmission line, and comprises the following steps: Acquiring solar photovoltaic predicted power data and real-time photovoltaic output power data of a system; calculating the upper limit of the number of the planned operating electrolytic cells based on solar photovoltaic predicted power data and rated power of a single electrolytic cell; determining the running number of the target electrolytic cells based on real-time photovoltaic output power data, the upper limit of the number of the planned running electrolytic cells and a preset power distribution rule; calculating hydrogen production distribution power based on the target running number of the electrolytic cells and real-time photovoltaic output power data; based on the target number of electrolyzer operations, the hydrogen production split power, and the equipment equalization rotation mechanism, a converter control command is generated. The invention eliminates frequent start-stop oscillation at the operation boundary and realizes multidimensional space-time balance of the bottom layer voltage stabilizing control role and the physical equipment. Drawings FIG. 1 is a flow chart of a cross-time scale multi-cell co-scheduling method of the present application. FIG. 2 is a flow chart of the present application for determining the number of target cells operated. Fig. 3 is a flowchart of generating a photovoltaic end control command according to the present application. FIG. 4 is a flow chart of generating hydrogen-producing end control instructions in accordance with the present application. Detailed Description In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention. It should be noted that the terms first, second, and the like in the description of the present invention and the above-described drawings are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention des