Photovoltaic installed capacity, as an important part of green new energy, will maintain rapid growth under the strong promotion of a new round of national policies. The traditional photovoltaic power station operation in China basically refers to the original substation operation mode, which adopts the mode of on-site management and control of operation and maintenance personnel, and has the characteristics of high labor cost input and slow fault response speed, which seriously affects the power generation income of photovoltaic system. At the same time, photovoltaic power stations are generally remote, and it is difficult for senior management of the group or company to directly understand the actual situation of the power station. To this end, this paper analyzes the status quo of the operation of photovoltaic power stations, and integrates intelligent sensor technology, digitalization and other technologies into the operation of photovoltaic power stations to make photovoltaic power stations smarter.
1.Operation and maintenance status of photovoltaic power stations in China
Due to the rapid development of the photovoltaic industry and the impact of subsidy policies, there has been a boom in the installation of photovoltaic power stations in recent years, resulting in a lack of precision and integrity in the construction of photovoltaic power stations, affecting the quality and investment returns of photovoltaic power stations. With the rapid expansion of the photovoltaic industry, the operation and management level of photovoltaic power stations is far from meeting the needs of its rapid development. Most of the sites of photovoltaic power stations are located in areas with rich light resources and low land costs, and it is difficult to recruit professional personnel for the operation and maintenance of photovoltaic power stations, and employees lack operation and maintenance experience.
2. Application of intelligent operation and maintenance technology of photovoltaic power station
2.1 Strict equipment selection
The equipment used in photovoltaic power plants includes photovoltaic modules and inverters. Among them, the photovoltaic module model is different, and the power generation is also large and small, so before installation, the appropriate equipment model should be selected according to the output power of the photovoltaic power station to improve the power generation efficiency and meet the power generation requirements. The model of the solar module is directly related to the design of the photovoltaic array, and the value of the solar module in the entire photovoltaic power station can account for more than 60%, so it is necessary to choose high-quality solar modules to ensure the reliable operation of the photovoltaic power station and improve the efficiency of power generation. In addition, the inverter is also the core equipment of photovoltaic power stations, to try to choose mature, good performance products, and ensure that the equipment warranty period is above 5a.
2.2 Technological innovative solutions
Technological innovation drives quality improvement and efficiency. The optical power prediction system is studied deeply, and the algorithm of power station optical power prediction system is optimized to improve the accuracy of optical power prediction. Optimize the tracking strategy of the tracking system, combine meteorological parameters of different regions, and utilize photovoltaic big data to optimize the tracking AI algorithm supported by flat single axis, so as to give full play to the power generation advantages of the tracking system; Apply the intelligent IV scanning function to scan the system comprehensively, reduce the matching loss and increase the power generation; Research on repair technology of components to reduce attenuation rate and attenuation loss of components. Intelligent operation and maintenance construction. Intelligent operation and maintenance can conduct in-depth analysis, accurate judgment and evaluation of the power station, so that the equipment is in the intelligent monitoring state, early detection of equipment failures, improve maintenance efficiency, save labor costs, and improve the operation level of the power station.
2.3 Inverter Maintenance
Inverter is the main electrical equipment of photovoltaic power station. The most common failure problem is internal component damage. However, the distribution and transportation of components are relatively slow, which is easy to cause dissatisfaction among power station owners. Therefore, when choosing an inverter, a comprehensive analysis should be carried out according to market development and the performance of the inverter provided by the manufacturer to ensure the quality of the supplier’s subsequent service. In addition, it is also necessary to consider the daily work level of photovoltaic power stations, and connect the inverters in series to provide convenience for later maintenance. During maintenance, the operating room temperature should be considered to ensure its stable operation, especially the heat dissipation and exhaust system, which is also the main area causing failure. After a periodic power failure, check whether the terminal copper bar of the output line is yellow or black. And in the maintenance inspection, listen to the internal work whether there is noise, vibration is within the scope of the specification, regularly clean the internal dust, to avoid excessive dust caused by the internal working temperature is too high.
2.4 Application of intelligent sensing technology in photovoltaic power stations
With the continuous development and maturity of smart sensor technology, its production cost will become lower and lower, and the application will gradually become popular. With the rapid development of 5G technology, smart sensors can achieve intelligent distributed control of devices. For example, the intelligent temperature sensor is applied to the transformer temperature measurement, and the temperature alarm value, tripping value, starting fan value, stopping fan value and other fixed values and logic are set. When the temperature reaches a fixed value, the information will be sent to the local communication manager through 5G communication, and then sent to the monitoring platform. At the same time, the anti-error operation logic can be set inside the smart sensor to make logical judgment on the temperature data. Only when the data of the two sensors at the same temperature measurement point are close to and meet the action value. Lighting sensors and temperature sensors are arranged near the photovoltaic array. Through the effective and timely comparison of the data of the two sensors, the relationship curves of the light intensity, temperature and active power of the photovoltaic array are extracted, and the active power prediction model is established. According to big data analysis and weather forecast, the power generation of photovoltaic power stations can be accurately predicted, and the implementation rate of photovoltaic power generation plans can be improved.
2.5 Strengthen inspections and inspections
Before the reform of the electrical equipment operation and maintenance system of large new energy power stations, comprehensive data statistics should be carried out. It is necessary to conduct a comprehensive survey of the various equipment used in the electrical equipment system, especially the information of equipment purchase and the process parameters of the equipment, to ensure that the basic information reserve is comprehensive. In this way, complete information can be provided for subsequent maintenance. In addition, it is necessary to carry out statistics on the daily operating status of the equipment, especially to predict the future service life according to the working status, which is also an important part of the inspection work.
2.6 Optimize procedures and standardize operation, improve operation and maintenance work level and program control ability
The overall operation and maintenance level of domestic photovoltaic power stations is low and lacks high strength. Only a small number of operation and maintenance personnel, daily work only involves routine maintenance, do not touch the content of procedures and system management. In the daily operation and maintenance, the staff is not clear about the current status of the power station in the operation and maintenance work, resulting in unclear responsibilities in the later period and can not grasp the key points.
2.7 Take active actions to improve the scheduling level during the operation of the power station
Nowadays, the evaluation of photovoltaic power plants by the power supervision and dispatching department is becoming more and more strict, and the evaluation standards are also spent on updating the indicators. In the field of electricity, no matter what the situation, power supply and electricity safety is always the first consideration. Photovoltaic power supply is intermittent and unstable, and according to the current system configuration and self-regulation of the power station, it can affect the safety after the penetration rate is increased to a certain height.
Closing remarks
The proportion of electricity supply in China is still large, but the coal resources consumed in power generation are already in a scarce state, and the development of new energy power generation is the trend of The Times. In the increasingly mature photovoltaic power generation, it is necessary to pay attention to the matching of operation and maintenance management to support the operation of energy storage power stations. In addition, considering the instability of photovoltaic power generation, it is necessary to cleverly set the power supply mode, and implement the power monitoring to ensure the power scheduling effect.
