Abstract: The photovoltaic power generation monitoring system, combiner box, inverter, AC/DC power distribution cabinet, solar tracking control system and other equipment are monitored and controlled in real time. Through various types of charts and data, the operation of the power station is quickly mastered. Its friendly user interface, powerful analysis function, and perfect fault alarm ensure the complete reliable and stable operation of the solar photovoltaic power generation system.
Keywords: Photovoltaic power generation, Intelligent power instrument, Acrel-2000, Power monitoring system
This project mainly monitors the roof photovoltaic power generation of Guangxi Jiaotou Building in real time through the power monitoring system, uses the Ankeri brand combiner box AGFT-M4, Shenzhen Keshida inverter KSG1-100K, and Licheng environmental detector to monitor the environmental parameters in real time, and uses the Ankeri multi-function meter to measure the power generation in the grid connection cabinet. The above devices are networked with the background through RS485 communication.
1. Demand analysis
To ensure the normal operation of photovoltaic power generation system. The voltage, current, power and other parameters of the combiner box and inverter at the project site need to be monitored online in real time. Through the environmental monitor, the weather conditions can be grasped in real time. Once the monitored parameters at the monitoring point are abnormal, the alarm can be given in a timely manner. Relevant personnel take corresponding measures to avoid safety accidents. The automatic meter reading function saves manpower and material resources, and the power trend curve function can intuitively display the working status of each circuit, so that users can understand the operation of the entire photovoltaic power generation system.
It can automatically collect analog data of all on-site electricity meters, and automatically collect on-site switch status, fault status and other switch data.
It supports real-time acquisition, automatic periodic acquisition (timed acquisition) and configurable cycle (1 minute to 24 hours).
Support the correctness check of data transmission and automatic processing of abnormal data.
Support multi-threaded processing mechanism, improve data collection efficiency, and collect data from multiple devices at the same time.
The real-time data display adopts the visual display mode of the main wiring diagram of photovoltaic power generation, and the on-off and fault status of each circuit are visible.
Data analysis and processing
Comprehensive statistics and analysis of data need to realize the following functions:
Statistics and calculation of power generation data of each combiner box in hours, days, months and years.
The maximum, minimum and average values of each generation power are calculated.
Statistics of power generation of each substation and the whole.
It is required to grant different roles to different users, which can be authorized to function submenus, specific file records, data records, etc.
The system requires a reasonable and perfect user security control mechanism, which can effectively protect the information resources in the application environment and prevent the loss, theft and destruction of information.
Provide data support for production energy-saving transformation, and provide effect evaluation before and after energy-saving transformation.
2. System Scheme
According to the actual situation of the photovoltaic power generation project in Guangxi Jiaotou Building, the overall network structure of the Anchery Acrel-2000 system is directly connected to the data collector by shielded twisted pair, and then uploaded the data to the monitoring host in the duty room through optical fiber, ensuring the stability and real-time transmission of the power monitoring system.
1) Station control management
The station control management is a direct window for human-computer interaction for the managers of the power monitoring system. In the photovoltaic power generation project of Guangxi Jiaotou Building, it mainly refers to the monitoring host placed in the distribution room on the basement.
2) Network communication layer
The communication layer is mainly composed of collector, Ethernet equipment and bus network. The main function of the communication management machine is to monitor the on-site intelligent instruments; The main function of Ethernet equipment and bus network is to realize the data interaction between the sub station and the master station, so that the management of the power generation system is centralized, information-based and intelligent, which improves the security, reliability and stability of the power generation system and achieves the goal of unattended.
3) Field equipment layer
The field equipment layer is the data acquisition terminal, which is mainly composed of intelligent instruments. The intelligent instruments are connected to the communication server through the shielded twisted pair RS485 interface and the MODBUS communication protocol bus connection. The communication server reaches the monitoring host in the duty room through optical fiber for networking to achieve remote monitoring.