Speedily deploying a stable and reliable industrial-grade wireless network system for a large-scale PV system of China Juli Group
In order to ensure that the non-fossil fuels account for 15% of China's energy consumption by 2020, the Chinese government has continued to release new energy policies to boost its domestic renewable energy use ratio.
Enterprise PV systems mainly supply power for their own needs and may sell excess power to the power company whereas Photovoltaic (PV) power plants specialize in solar energy collection and then feeding the energy into the grid.
To transmit the data of the PV systems wired or wireless networks can be used. However, wireless networks have the advantage of flexibility and are the best choice for those who want quick deployment.
Located in Baoding City of Hebei Province, the Juli Group was using an enterprise PV system onthe roofs of its own plants,. Initially, the PV system was only installed in one plant for small scale trial, so the company’s existing wired network was to transmit data. With good power generation, the company intended to expand the use of solar cells to the whole factory area which covers 2,000 square meters and includes three factories of 18 buildings. Therefore, a new PV monitoring system was required.
Taking into account the requirements of wider coverage and long-distance transmission, the existing fiber-optic networks had many shortcomings ie high cost, complicated wiring and long construction period, and it may also have been necessary to excavate walls, drill holes, embed wires, or even destroy the original building structure. After evaluation, the Juli Group decided to adopt an easy installation and easy expansion wireless network system for early completion of this project.
Because it would be installed outside on the roofs of buildings, the wireless system had certain requirements. One of which was that they had to cope with the extremes of temperature where it can drop to as low as minus ten in winter and plus 40 in the summer. For security purposes surveillance cameras would also be installed and having sufficient network bandwidth to transmit the PV and video data was also necessary.
In order to avoid excessive bandwidth consumption when bridging Access Points (AP) and considering both deployment cost savings and system expandability, detailed network architecture planning was necessary to ensure the wireless network system would provide stable transmission and meet future expansion needs.
To meet these requirements, Advantech utilized two EKI products to build a Mesh backbone network with multiple wireless AP nodes, so as to meet customer’s requirements of rapid implementation, stable transmission and cost savings. The backbone base station used the EKI-6340-3 which has received a Chinese Innovation Award to provide excellent expansibility and flexibility for users to deploy an optimized wireless network system. Among its many functions, the three radio interfaces enable the wireless interconnection of APs throughout various plants. Providing redundancy and setting up a link in the 5.8GHz band also enhanced the stability of network operations.
By leveraging the advanced industrial Mesh technology, this industrial-grade wireless AP features self-healing and self-forming capabilities allowing the wireless network to extend communication range according to various application conditions and having the failure recovery within 20 ms to ensure the smooth transmission of data. Because the EKI-6340 supports 802.11n 2x2 MIMO, it guarantees transmission quality for both general and video data at a higher bandwidth with faster speed (maximum 300Mbps).
Also included in the network was a series of affordable and feature-rich EKI-6331AN industrial wireless APs. Through its embedded 16DdBi 5.8GHz dual-polarization (MIMO) directional antenna it directly connects to the backbone base station, and saves the implementation costs of additional antennas and feeders. Like the aforementioned wireless EKI-6340, the EKI-6331AN also supports 802.11n 2x2 MIMO giving it a three times faster data transfer rate compared to 802.11a devices. To strengthen the wireless network data security, it implements the latest encryption technologies including WPA2/WPA/802.1x to protect the data of the PV system.
Because of the location’s severe weather, the EKI devices were chosen for their international IP waterproof and dustproof certification, thereby giving users the assurance that they operate whether it is bitter cold or blazing hot. In addition to its own products, Advantech used its expertise to supply accessories from long-term partners, including directional antenna, sector antenna, splitters, feeder lightning arrestermodule and network lightning protection module to secure the outdoor wireless devices against wind and lightning while ensuring uninterrupted communication quality.
- EKI-6340-3: IEEE 802.11 a/b/g/n Wi-Fi AP/Client
- EKI-6331AN:IEEE 802.11 a/n Wi-Fi AP/CPE
Wireless Mesh Network Topology
By implementing Advantech’s intelligent PV plant monitoring solution, owners like the Juli Group don’t need to worry about compatibility between products and peripheral devices and can have astable and reliable system through our high degree of seamless integration. After completion, this remotely centralized management platform with visible, manageable and controllable features not only saved manpower and resources but also significantly enhanced the operation and maintenance effectiveness by real-time monitoring and unified management.