Development of distributed photovoltaic grid-connection device

作者：Ding, Ming; Yao, Yuliang; Li, Lin; Bi, Rui; Cao, Jun

来源：Electric Power Automation Equipment, 2018, 38(3): 1-6 and 15.

DOI：10.16081/j.issn.1006-6047.2018.03.001

• Anti-islanding protection
• Grid connections
• Phase angle differences
• Photovoltaic grid connections
• Photovoltaic power generation
• Prediction algorithms
• Relay protection systems
• Zero sequence current protections

The distributed photovoltaic grid-connected device with dual-CPU is designed based on ARM Cortex-M4 core 32 bit chip, including master control CPU and communication CPU. By modular design and sampling of integrated data, the device can realize information interaction with dispatch center of distribution network, inverters and other intelligent devices, and has the functions of direction and compound voltage blocking overcurrent protection, reverse power protection, zero sequence current protection, overload protection, passive anti-islanding protection, synchronization grid-connection, and so on. Considering the high requirement of distributed photovoltaic plant on synchronization grid-connection, the different-frequency grid-connection algorithm based on catching closing point based on phase-angle difference prediction of sampling point. Test results of microcomputer relay protection system show that, the designed device can collect data correctly and the protection can act reliably. Compared with the traditional different-frequency grid-connection algorithm, the proposed algorithm can improve the grid-connection accuracy effectively.

• 出版日期2018
• 单位合肥工业大学