CN-121981322-A - Offshore photovoltaic power generation unit optimization method

CN121981322ACN 121981322 ACN121981322 ACN 121981322ACN-121981322-A

Abstract

The offshore photovoltaic power generation unit optimizing method comprises the steps of combining size limitation of photovoltaic supports and series connection digital electric performance requirements of photovoltaic modules of a transport ship, optimally arranging rows and columns of the photovoltaic modules of different sizes on the photovoltaic supports, optimally combining the photovoltaic module power, capacity matching requirements and serial type inverters of different powers of the optimized single photovoltaic supports according to the optimized photovoltaic module power, capacity matching requirements and serial type inverters of different powers, achieving installation and laying of the photovoltaic modules, the serial type inverters and the photovoltaic direct current cables on land, optimizing capacities and shapes of the offshore photovoltaic power generation units, carrying out technical and economical measurement and calculation on the cable consumption and installation and laying aspects of the photovoltaic power generation units of different capacities and shapes, and optimizing operation economy of the cable section. The photovoltaic direct-current cable can be prevented from crossing different photovoltaic brackets, electric wiring is clear and simple, capacity and shape of the photovoltaic power generation unit are optimized, and single-watt investment of the photovoltaic power generation unit and construction difficulty of cable laying are reduced.

Inventors

KOU FENGHAI
DUAN WEIWEI
REN FEIFAN
LU WEI
CHEN TONG
LIANG HAOTIAN

Assignees

中国电建集团河北省电力勘测设计研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20260105

Claims (6)

1. The offshore photovoltaic power generation unit optimization method is characterized by comprising the following steps of: S1, optimizing arrangement of rows and columns of photovoltaic modules with different sizes on a photovoltaic support by combining size limitation of the photovoltaic support and serial digital and electric performance requirements of the photovoltaic modules by a transport ship, so that maximum power of the photovoltaic modules on a single photovoltaic support is realized, and engineering cost is reduced; S2, optimizing and combining the photovoltaic module power and capacity ratio requirements of the optimized single photovoltaic bracket and the existing string type inverters with different powers to realize that the photovoltaic module, the string type inverter and the photovoltaic direct current cable are installed and laid on land, so that the photovoltaic direct current cable is prevented from being laid across a platform, and the offshore construction amount and difficulty are reduced; s3, optimizing the capacity and the shape of offshore photovoltaic power generation units, and performing technical and economical measurement and calculation on the photovoltaic power generation units with different capacities and shapes in terms of cable consumption, installation and laying to obtain the capacity and the shape of the offshore photovoltaic power generation units with the lowest single-watt investment and convenient cable laying; And S4, optimizing the operation economy of the cable section, namely, gradually increasing the cable section on the basis of meeting the continuous current-carrying capacity requirement of the loop, calculating the cable loss under each section, comparing the electric charge income caused by loss reduction in the whole life cycle with the initial investment increase cost, and if the electric charge income is larger than the initial investment increase cost and is the maximum value, obtaining the optimal operation economy section of the cable.
2. The method for optimizing an offshore photovoltaic power generation unit according to claim 1, wherein the specific steps of the step S1 are as follows: (1) There is a need to first determine the allowable transport size of an economical marine vessel; (2) Calculating the row and column number of the photovoltaic modules on the photovoltaic bracket according to the determined transportation size, and adjusting and optimizing the row number and the column number of the photovoltaic modules according to the calculation result; (3) And calculating an allowable range value of the series number of the photovoltaic modules meeting the open-circuit voltage and MPPT working voltage ranges, and dividing the series number of the photovoltaic modules on the photovoltaic support.
3. The method according to claim 1, wherein in the step S2, the modular design of the photovoltaic support platform corresponding to the '1+X' inverter is performed according to the power level of the string-type inverter, wherein X is 0,1, 2.
4. The method for optimizing an offshore photovoltaic power generation unit according to claim 1, wherein the specific steps of the step S3 are as follows: (1) Determining the capacity of the photovoltaic power generation unit with the lowest single watt investment; (2) And determining the shape of the photovoltaic square matrix.
5. The method for optimizing an offshore photovoltaic power generation unit according to claim 1, wherein the capacity of the offshore photovoltaic power generation unit obtained in the step S3 is not less than 6MW, and the ratio of east-west length to south-north width is not less than 1.5.
6. The method for optimizing an offshore photovoltaic power generation unit according to claim 2, wherein the allowable range of the series number of photovoltaic modules is as follows: ; -an open-circuit voltage temperature coefficient of the photovoltaic module; -an operating voltage temperature coefficient of the photovoltaic module; -photovoltaic module series number (N-th); -extreme low temperature (°c) of the photovoltaic module in the daytime environment; -a cell limit high temperature (°c) of the photovoltaic module in the operating state; -maximum system voltage allowed by the inverter and the photovoltaic module, taking both small values (V); -inverter MPPT voltage minimum (V); -an open circuit voltage (V) of the photovoltaic module; -an optimal operating voltage (V) of the photovoltaic module.

Description

Offshore photovoltaic power generation unit optimization method Technical Field The invention belongs to the field of new energy offshore photovoltaic power generation, and particularly relates to an offshore photovoltaic power generation unit optimization method. Background With urgent demands for transformation and sustainable development of global energy structures, offshore photovoltaic power stations are receiving global attention as a novel renewable energy power generation mode. The ocean-based photovoltaic power station utilizes the wide space of the ocean, can effectively relieve the land resource pressure of the land photovoltaic power station, and can improve the power generation efficiency of the photovoltaic cell panel through the cooling effect of the seawater. However, the electrical design of offshore photovoltaic power plants faces challenges such as the complexity of the marine environment, the corrosion protection and moisture protection of electrical equipment, the laying and maintenance of cables, etc. The research of electric design optimization of an offshore photovoltaic power station is becoming a hot spot in the field of new energy, the offshore photovoltaic power station consists of a plurality of photovoltaic power generation units, each photovoltaic power generation unit consists of a photovoltaic square matrix, a string-type inverter, an on-site boosting transformer and an alternating current cable, and the photovoltaic square matrix consists of a photovoltaic module string, a photovoltaic bracket and a photovoltaic direct current cable, wherein the photovoltaic module string is formed by connecting a plurality of photovoltaic modules in series. In recent years, with the strong support and investment of renewable energy sources by the country, the construction of offshore photovoltaic power stations is gradually accelerated. Research documents in the aspects of type selection and optimization of electrical equipment of offshore photovoltaic power stations, cable laying and maintenance, influence of marine environment on the electrical equipment and the like are hardly reported in China, and part of the documents are also related to fishing light complementary projects. Therefore, the development of the electric design optimization research of the offshore photovoltaic power station has important significance for improving the power generation efficiency of the offshore photovoltaic power station, guaranteeing the safe and stable operation of the offshore photovoltaic power station, reducing the engineering investment and promoting the development of renewable energy sources. Disclosure of Invention The invention aims to provide an offshore photovoltaic power generation unit optimization method. The technical scheme of the invention is as follows: An offshore photovoltaic power generation unit optimization method comprises the following steps: S1, optimizing arrangement of rows and columns of photovoltaic modules with different sizes on a photovoltaic support by combining size limitation of the photovoltaic support and serial digital and electric performance requirements of the photovoltaic modules by a transport ship, so that maximum power of the photovoltaic modules on a single photovoltaic support is realized, and engineering cost is reduced; S2, optimizing and combining the photovoltaic module power and capacity ratio requirements of the optimized single photovoltaic bracket and the existing string type inverters with different powers to realize that the photovoltaic module, the string type inverter and the photovoltaic direct current cable are installed and laid on land, so that the photovoltaic direct current cable is prevented from being laid across a platform, and the offshore construction amount and difficulty are reduced; s3, optimizing the capacity and the shape of offshore photovoltaic power generation units, and performing technical and economical measurement and calculation on the photovoltaic power generation units with different capacities and shapes in terms of cable consumption, installation and laying to obtain the capacity and the shape of the offshore photovoltaic power generation units with the lowest single-watt investment and convenient cable laying; And S4, optimizing the operation economy of the cable section, namely, gradually increasing the cable section on the basis of meeting the continuous current-carrying capacity requirement of the loop, calculating the cable loss under each section, comparing the electric charge income caused by loss reduction in the whole life cycle with the initial investment increase cost, and if the electric charge income is larger than the initial investment increase cost and is the maximum value, obtaining the optimal operation economy section of the cable. The technical scheme of the invention is further improved in that the specific steps of the step S1 are as follows: 1. there is a need to first determine the allowable