CN-121984060-A - Multi-type energy storage power electronic system optimization method and system

Abstract

The application provides a method and a system for optimizing a multi-type energy-storage power electronic system, wherein the method comprises the steps of comparing current output waveforms of a plurality of different types of energy storage devices in the power electronic system with current energy storage waveforms, identifying interfered devices according to waveform differences, identifying interfered device groups with mutual interference relations through time interval cross analysis based on interference time intervals of the interfered devices, determining test periods of devices in the interfered device groups based on alternating periods of the devices, selecting candidate values as execution ratios in a preset duty ratio regulation range, adjusting conduction time of each device to achieve peak staggering, and selecting optimal process execution by evaluating interference degrees under different parameter combinations. According to the technical scheme provided by the application, the effective suppression of multi-equipment interference is realized, and the charging quality, the energy conversion efficiency and the operation stability of the energy storage system are obviously improved.

Inventors

• LI XIAOCHEN
• LIU MINGYI
• CAO CHUANZHAO
• PEI JIE
• XU RUOCHEN
• LV JIAN
• HAN HUI
• LIU CHENGHAO
• CHEN YIPAI
• ZHANG QI
• ZHANG DE
• GU YI
• LEI HAODONG
• CAO XI
• ZHOU LIREN
• LIU BO
• YAO SIXU
• WANG YANLING
• WU JIAN

Assignees

• 华能国际电力股份有限公司上海石洞口第二电厂
• 中国华能集团清洁能源技术研究院有限公司

Dates

Publication Date

20260505

Application Date

20251208

Claims (10)

1. 1. A method of optimizing a power electronic system for multi-type energy storage, the method comprising: comparing current output waveforms of a plurality of energy storage devices of different types in the power electronic system with current energy storage waveforms, and identifying interfered devices according to waveform differences; Identifying an interfered equipment group with a mutual interference relationship through period crossing analysis based on the interference period of the interfered equipment; and determining a test period based on the alternating period of the equipment in the interfered equipment group, selecting a candidate value as an execution ratio in a preset duty ratio regulation range, adjusting the on time of each equipment to realize peak staggering, and selecting an optimal process for execution by evaluating the interference degree under different parameter combinations.
2. 2. The method of claim 1, wherein comparing the current output waveforms of the plurality of different types of energy storage devices in the power electronic system to the current storage waveforms and identifying the interfered device based on the waveform differences comprises: in a preset monitoring period, controlling the energy storage devices of different types to charge synchronously, and respectively acquiring a current output waveform and a current energy storage waveform of each device in the monitoring period; performing time calibration on the current output waveform and the current energy storage waveform, and then calculating waveform deformation values point by point, wherein the waveform deformation values are differences of current amplitudes of adjacent sampling points; comparing waveform variable values of the two waveforms in the same time period, and marking the time period with inconsistent waveform variable values as an abnormal wave band; If the accumulated time length of the abnormal wave band in the current energy storage waveform of the energy storage device exceeds a preset first threshold value, judging that the energy storage device is an interfered device; wherein the preset first threshold is 30%.
3. 3. The method of claim 2, wherein the identifying the group of interfered devices having a mutual interference relationship by period crossing analysis based on the interference period of the interfered devices comprises: determining an interference period corresponding to each abnormal wave band of each interfered device; each interfered device is subjected to pairwise combination to judge whether the interference period of each pair of devices has a crossing period; if the cross time period exists, calculating the proportion of the cross time period to the respective interference duration of the two devices, and calculating the average value of the two proportions; if the average value is larger than a preset second threshold value, judging that the two devices have mutual interference relationship, and forming an interfered device group; wherein the preset second threshold is 50%.
4. 4. The method of claim 3, wherein the step of combining is performed if there are multiple groups of devices sharing the same interfered device; wherein the merging step includes: identifying other devices which have interference relation with the same interfered device to form a device set; If the mutual interference relationship exists between any two devices in the device set, combining the same interfered device and each device in the device set into one interfered device group.
5. 5. The method of claim 4, wherein the selecting optimal process execution for the devices in the interfered device group by evaluating the interference degree under different parameter combinations based on the alternating period of the devices, determining the test period, selecting candidate values in the preset duty cycle regulation range as the execution ratio, and adjusting the on time of each device to realize peak staggering comprises: S31, taking each device in the interfered device group as a debugging device, and acquiring the original duty ratio and alternating period of each debugging device; s32, calculating the least common multiple of the alternating period of each debugging device, and taking the least common multiple as a test period; S33, setting a duty cycle regulation range of ZB i ±C1×ZB i for each debugging device, wherein ZB i is the original duty cycle of the ith device, C1 is a preset regulation coefficient, and 0< C1<1; s34, uniformly dividing the regulation and control range of each debugging device into N micro ranges, and selecting the intermediate value of each micro range as a candidate execution ratio of the device, wherein N is an integer greater than 1; s35, selecting a candidate execution ratio of each debugging device to form a parameter combination in the test period, and adjusting the conduction time of each debugging device to minimize the conduction time overlap between the devices; s36, calculating interference evaluation indexes of each debugging device under the parameter combination and time adjustment, and calculating an average value of the interference evaluation indexes of each debugging device to be used as a period characteristic value corresponding to the current test period; s37, traversing different parameter combinations, and repeating the steps S35 and S36 to obtain a plurality of period characteristic values; S38, selecting a parameter combination corresponding to the minimum period characteristic value and conducting time arrangement as an optimal process and executing the optimal process.
6. 6. The method of claim 5, wherein the interference assessment indicator is a duration duty cycle of an anomaly band in a current energy storage waveform.
7. 7. The method of claim 6, wherein adjusting the on-time of each commissioning device to minimize on-time overlap between devices comprises: Under the constraint of meeting the self alternating period and the execution ratio of each device, the conduction time schedule which minimizes the total conduction overlap time of each debugging device is searched.
8. 8. A power electronics system optimization system for multi-type energy storage, the system comprising: the first identification module is used for comparing current output waveforms of a plurality of different types of energy storage devices in the power electronic system with the current energy storage waveforms and identifying interfered devices according to waveform differences; the second identifying module is used for identifying the interfered equipment group with the mutual interference relationship through time interval cross analysis based on the interference time interval of the interfered equipment; And the optimization module is used for determining the test period of the equipment in the interfered equipment group based on the alternating period of the equipment, selecting a candidate value as an execution ratio in a preset duty ratio regulation range, adjusting the conduction time of each equipment to realize peak staggering, and selecting an optimal process for execution by evaluating the interference degree under different parameter combinations.
9. 9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the method according to any of claims 1-7 when executing the program.
10. 10. A computer readable storage medium, on which a computer program is stored, characterized in that the program, when being executed by a processor, implements the method according to any of claims 1-7.

Description

Multi-type energy storage power electronic system optimization method and system Technical Field The application relates to the technical field of power energy storage, in particular to a power electronic system optimization method and system for multi-type energy storage. Background Under the background of continuous improvement of new energy permeability and rapid development of novel power systems, multiple types of energy storage technologies (such as lithium batteries, super capacitors, flywheel energy storage, vanadium redox flow batteries and the like) are widely and jointly applied to the scenes of micro-grids, new energy grid connection, grid peak regulation and the like due to the complementary characteristics of the power density, the energy density and the response speed of each energy storage technology, and the high-efficiency energy storage modes of 'stabilizing instantaneous fluctuation of high-power equipment and bearing long-term energy regulation of the high-energy equipment' can be realized through the cooperative operation of different types of energy storage equipment, so that the flexibility and the economy of the system are remarkably improved. When the multi-type energy storage equipment is in integrated operation, a power electronic system of the multi-type energy storage equipment faces serious interference problems that power electronic interfaces (such as a converter and an inverter) of different energy storage equipment can generate current waveforms with different characteristics in the charging and discharging processes, and the power electronic interfaces are influenced by inherent alternating periods (such as switching frequency and charging and discharging period) of the equipment and control strategy differences (such as PWM modulation mode and charging and discharging current setting), and current harmonic coupling and electromagnetic interference are easy to form among the equipment. The method is characterized in that current fluctuation is aggravated due to harmonic invasion in the charging process of part of equipment, charging quality is reduced (such as the risk of overcharge and overdischarge of a battery is increased and energy storage efficiency is reduced), and when multiple pieces of equipment are operated simultaneously, if conduction periods are overlapped, current superposition distortion is caused, interference effects are further amplified, the service life of the equipment is shortened, the stability of a system is reduced, and even the voltage/frequency stability of a power grid or a micro-grid is influenced. The processing of the interference of the energy storage system is concentrated on local optimization of single equipment (such as adding a passive filter and optimizing a single-equipment PWM algorithm), or depends on an empirical period matching strategy, and systematic identification and quantitative analysis of the interference relation among multiple equipment are lacked. For example, the traditional method is difficult to accurately position the equipment groups interfering with each other, the association characteristics of the interference sources and the interfered equipment cannot be distinguished, and in the regulation and control optimization stage, the cooperative peak staggering of the alternating periods of multiple equipment is often not considered, so that the anti-interference effect is limited, and the problem of new parameter matching is easy to cause. In addition, the evaluation of the interference degree in the prior art lacks clear quantitative indexes, so that the accurate measurement of the interference suppression effect and the scientific selection of an optimization strategy are difficult to realize, and the improvement of the efficiency and the reliability of the integrated operation of the multi-type energy storage system is restricted. Therefore, there is a need for a solution that enables optimization of power electronic systems for multiple types of energy storage. Disclosure of Invention The application provides a method and a system for optimizing a power electronic system with multi-type energy storage, which at least solve the technical problems of low efficiency and low reliability of integrated operation of the multi-type energy storage system. An embodiment of a first aspect of the present application provides a method for optimizing a power electronic system for multi-type energy storage, the method including: comparing current output waveforms of a plurality of energy storage devices of different types in the power electronic system with current energy storage waveforms, and identifying interfered devices according to waveform differences; Identifying an interfered equipment group with a mutual interference relationship through period crossing analysis based on the interference period of the interfered equipment; and determining a test period based on the alternating period of the equipment in the interfere