Photovoltaic energy has become the most potential and advantageous renewable energy source. Due to photovoltaic applications, photovoltaic power generation has gradually entered ordinary people's homes in forms of ground photovoltaic power stations and roof photovoltaic power stations. Therefore, it is necessary to understand photovoltaic power generation from various angles.
1. Why should we pay attention to the quality monitoring of distributed photovoltaic power generation system?
Firstly, distributed photovoltaic power generation systems are mostly combined with buildings. If there is a problem in system quality, it may not only cause damage to the internal equipment of the power generation system, but also endanger the safety of the power distribution station and the surrounding personnel of the building. Secondly, distributed photovoltaic power generation systems are mostly for personal use. If there is a problem in system quality, it may cause damage to the electrical equipment. Thirdly, distributive power generation system obtains economic benefits by generating electricity. If there are quality problems, it will affect the generating capacity and life of the whole system, thus affecting the income of the whole system.
2. Does the qualification of each component mean that the system integration need not be tested?
Although photovoltaic power generation system is composed of various components, the qualification of each component does not mean that the system integration is qualified. The overall design and configuration, safety and operational performance of the system need to be tested and verified.
3. How to select qualified system accessories and how long is the warranty period?
It is recommended to select the system accessory products approved by the national certification authority. The specifications, models and technical parameters of the system accessory products shall conform to the design requirements of the whole system. Generally speaking, the components shall be guaranteed for five years, while the inverters shall be guaranteed for at least two years.
4. What product certifications are required to obtain state subsidies?
In the acceptance link of power grid, the completed photovoltaic power generation system cannot pass the acceptance until it meets the corresponding safety standards and quality requirements. The main equipment in the photovoltaic power generation system, including components, junction boxes, inverters, etc., all need corresponding domestic certification.
5. How to judge the quality of distributed photovoltaic grid-connected system?
The quality of distributed photovoltaic grid-connected system can only be determined through comprehensive detection of components and systems. The detection content includes detection of each component, and detection of safety and performance of the system.
6. After quality problems occur in distributed photovoltaic grid-connected systems, what maintenance procedures will suppliers follow and how long will it take?
After a quality problem occurs in the distributed photovoltaic grid-connected system, on-site maintenance personnel need to judge the problem points and feed them back to the supplier. The supplier usually sends engineers to the site to confirm the quality problem and solve it. If the quality problem is caused by key equipment, the supplier will contact the equipment manufacturer, and the engineers of the equipment manufacturer will usually come to the site within one week to carry out maintenance treatment.
7. How do owners roughly judge the merits and demerits of their photovoltaic systems? How should the quality problems suspected in the system be solved?
The owner can make a preliminary judgment from the following aspects: firstly, inspect the system appearance, such as components, arrays, junction boxes, etc. if problems are found, take corresponding measures to solve them in time. Then the owner should check whether the system components adopted by the power station construction contractor have quality certification, and also conduct on-site tests on the system safety to check the continuity and insulativity of grounding wire and whether it has lightning protection device. Besides the system electrical efficiency should be tested. If problems are found, the construction unit of power station should solve them in time.
8. How to judge whether the distributed photovoltaic grid-connected system works stably, whether the power quality meets the requirements, and whether damage will be caused to household appliances when the system breaks down?
Distributed photovoltaic grid-connected systems generally have a function of data monitoring. It can be judged whether the system operates stably by analyzing the monitoring data. If conditions permit, power quality analysis can also be used to test the power quality of the grid-connected points of the power station to see whether it meets the requirements of national standards. In case of photovoltaic system failure, generally a protection device will cut off the power supply, thus causing no damage to household appliances.
9. Is the monitoring data of power generation in the distributed photovoltaic grid-connected system the same as the metering data of the electricity meter? What is the error?
The monitoring data of power generation in the distributed photovoltaic grid-connected system are not necessarily the same as the metering data of the electricity meter. For example, if the same power metering equipment is used in the same grid-connected node and the accuracy is completely the same, the obtained data should be the same. However, the monitoring equipment used in the photovoltaic grid-connected system is often the equipment used by the system construction unit itself, and the metering equipment of the electricity meter is often the equipment belongs to the power department. Therefore, there may be some differences between the data obtained by different equipment, and the error depends on the specific situation. The settlement of electricity and subsidy costs is based on the metering equipment installed by the power department.
10. How to monitor the amount of electricity connected to the grid?
At present, the grid-connected photovoltaic power generation system is mainly monitored by installing an electric energy meter
approved by the local power department at the grid-connected point. In addition, the local power debugging center can usually monitor the grid-connected photovoltaic power generation system through remote communication. The owner can also build a simplified information system to monitor and optimize the grid-connected power generation.
11. Can the power generation of the system be monitored online?
Each enterprise in power grid shall cooperate with the competent department of energy at the corresponding level and carry out measurement, information monitoring and statistics of distributed power generation within the coverage area of the power grid. If the user's photovoltaic system is equipped with a corresponding monitoring system, on-line monitoring of power generation can be realized. In addition, the monitoring system can also realize on-line monitoring of parameters of key equipment, power quality, environmental parameters, etc.